Ventricular Tachycardia

AP19‐­00019

Radiofrequency ablation of deep seated outflow tract ventricular tachycardia using custom modified bipolar irrigated radiofrequency ablation setup

Jayapandian Pandian

Meenakshi Mission Hospital and Research Centre, India

Introduction:

Trans‐­catheter radio frequency ablation (RFA) of outflow tract ventricular tachycardia has a decent success rate of up to 82%. But the recurrences are possible in half of patients on long term follow‐­up. 1 Improvement in mapping and RFA technologies try to increase both acute and long‐­term success rates. 2 RFA catheter with the capacity to show real time tip to tissue contact force has been reported recently in outflow tract tachycardia to create a transmural lesion. 3 Deep seated intramural arrhythmic sources often not reachable by the standard RFA catheters. Failure to ablate such foci even by the irrigated RFA catheters is not uncommon. Bipolar RFA (bRFA) is necessary in such scenarios. But it is not widely used because of the non‐­availability of the equipment in all cardiac electrophysiology laboratories (EP‐­lab). 4 We describe the feasibility of bRFA in a standard EP‐­lab by simple modification of the existing RFA circuit.

Methods:

A 38 years old lady with the history of recurrent episodes of drug refractory palpitations and presyncopal episodes was referred for RFA. The echocardiogram revealed tachycardiomyopathy with the left ventricular ejection fraction of 46%. At baseline, electrocardiogram showed ventricular trigeminy. The focus of origin was suspected from right ventricular outflow tract (RVOT) as the morphology was LBBB with an axis of +110°. Transition was noted in V4 and the QRS in Lead I was positive which suggested the RVOT postero‐­septal region as the exit point. With the decapolar catheter in coronary sinus (CS), rowing catheter (4 mm open irrigated RFA catheter) was used for mapping the RVOT was mapped using impedance based 3 dimensional electro anatomical mapping system (3D‐­ EAMS). 3D‐­EAMS showed the RVOT postero‐­septal region as the earliest point, 28 ms ahead of the surface QRS. Pace mapping from the same point showed 12/12 match. Hence radiofrequency energy (RF) was delivered with ‐­‐­‐­‐­‐­ temperature, ‐­‐­‐­‐­‐­‐­‐­ power for ‐­‐­‐­‐­‐­‐­ seconds. The premature ventricular complexes (PVC) disappear after ‐­‐­‐­‐­‐­ seconds of ablation. Within 3 minutes PVC started to reappear. ‐­‐­‐­‐­‐­‐­ more episodes of RF energies were delivered at the same settings. As the PVC once again reappeared left ventricular outflow tract was mapped retrogradely with the same open irrigated rowing catheter. During 3D mapping rowing catheter was accidentally entered left main coronary artery (LMCA) and the moment was used for mapping the LMCA. The earliest point was found to arise from left coronary cusp (LCC), 30 ms ahead of surface QRS. Few RF energies were delivered at the earliest point after the confirmation of safe distance of LMCA location from the RFA site by angiogram. During ablation PVC were accelerated and terminated, yet recurrence happened in few minutes. Hence a try to search for other areas like anterior mitral commissure (which was late) was done but failed to identify the earliest region. Maximum deflection index (MDI) was measured to rule out the epicardial origin. As the MDI was 0.68, left ventricular summit was tried for mapping through CS but failed because of small anterior interventricular vein. Epicardial mapping was in the plan through pericardial sheath. But one another reason for MDI > 0.55 was deep seated focus apart from epicardial site. Hence a bRFA of outflow tract was considered before epicardial mapping. As the EP‐­Lab did not have the bRFA hardware it was decided to use custom made setup as described below. Bipolar RFA setup Irrigated RFA catheter (TherapyTM Cool flexTM) catheter was placed in RVOT and another open irrigated RFA catheter (FlexabilityTM) was placed in LCC at the corresponding earliest points. RVOT catheter was irrigated using the standard circuit and LVOT was irrigated using 50 mL syringe manually. LVOT catheter was connected to the anodal end of ablator via an 85641 ablation cable and the cathode port of ablator was connected to the jumper cable via a custom made cable for grounding. Jumper cable was connected to the junction box. The other end of the jumper cable was connected to the RVOT catheter through an Inquiry decapolar cable and the circuit was completed. First the bipolar RF energies were delivered using RVOT end as active ablation point and the LVOT end as the ground but not succeeded. When the bRFA was done using LVOT end as active ablation point and RVOT end as grounding using 20 watt power at 43 degree Celsius, RVOT ventricular tachycardia was accelerated immediately and terminated. Vigorous induction protocol was used post RFA to check the recurrence but PVC did not recur. At 3 months follow‐­up LVEF was normalized and neither 24 hours Holter nor exercise ECG reveals any PVC.

Result:

Unipolar configuration is used in standard RFA, between the ablation catheter tip and a ground patch placed on the body surface of the patient. Outflow tract tachycardia is usually ablated using unipolar radio frequency ablation (uRFA) with a good success and less recurrence. Poor contact of the ablation catheter, incomplete mapping and deep seated foci in the outflow septum are generally considered as the reasons for recurrence. Recently contact force catheter has been used to overcome the contact issue as the reason for failure. The deep seated foci are generally dealt with irrigated cooled ablation catheter in order to enhance the energy delivery into the deep tissue. Steam pop is a problem during ablation of the deep seated foci higher energy. RFA from both side of the outflow septum can be the option either alternately using single uRFA or double uRFA simultaneously, but the later requires two ablators. The configuration of uRFA circuit was custom modified into bRFA circuit, such that instead of the impedance patch, a second ablation catheter was designated as the grounding connection for the active RFA catheter. But the connection requires a distal port of a decapolar cable and a jumper cable. This report demonstrates the feasibility of bipolar ablation across outflow tract septum in a resistant scenario using easily available decapolar and jumper cables. As the mapping system (EnSite Precision, Abbott) is impedance based open system both the active and grounding RFA catheters can be visualized in the 3D‐­EAM as well as associated EGMs simultaneously. Usually the size and depth of the lesion on the active catheter side is bigger than the grounding catheter site. Hence changing the active and grounding vice versa should be tried in case if first one fails. In our case success was achieved while switching the active ablation end as LVOT and grounding end as RVOT. Sauer PJ et al reported successful ablation of midmyocardial septal outflow tract VT using custom modified bipolar ablation setup. They used a T‐­cable that was used to refine recordings from an RFA catheter with an old RF generator and NavX system. The distal pin of the T‐­cable was connected to the jumper cable and which in turn connected to the grounding port. 4 We used the decapolar cable in place of the T‐­cable as we did not have the inventory. To our knowledge after the extensive literature search, this is the first case report of bipolar ablation in India. Currently an investigational device is under evaluation to assess safety and efficacy of bRFA, in which not only the simultaneous visualization of both the catheters but also intercatheter distances and active catheter force registration is possible (ClinicalTrials.gov; Clinical Study Identifier: NCT02374476). Limitations: Surrogate points for contact and stability of the ablation catheter which is considered as grounding is not possible. Off‐­label use of custom modified equipment requires specific informed consent from the patient. The risks of charring, steam pop and fistula formation were not studied yet. During bRFA temperature and impedance data are only available from the active RFA catheter site, hence char formation or steam pop at the grounding catheter site could not be monitored. Intra cardiac echocardiography may be useful for monitoring the grounding catheter site.

Conclusion:

Deep seated septal origin of foci, where energy delivery is not reaching even with the standard open irrigated RFA catheter, bRFA may give success. The setup of bRFA can be easily made from the standard inventory in any one of the EP lab in our country. Not to forget large randomized study is required to prove the safety, feasibility and outcome of bRFA.

AP19‐­00028

Arrhythmia management in pregnant patient with Andersen‐­Tawil syndrome

Pongprueth Rujirachun, Apichaya Junyavoraluk, Arjbordin Winijkul, Bhoom Suktitipat, Manop Pithukpakorn

Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand, Thailand

Introduction:

Andersen‐­Tawil syndrome (ATS) is a rare inherited disease characterized by ventricular arrhythmias (VAs), periodic paralysis, and dysmorphic features. In the condition with pregnancy and childbirth, there is no guideline for providing effective treatment to suppress VAs.

Methods:

We report a case detailing the management of a pregnant patient with ATS safely undergoing childbirth.

Result:

A 32‐­year‐­old Thai woman came to seek an advice regarding to planning for pregnancy. She had a history of abnormal cardiac rhythm detected by doctor without symptoms, ECG was evaluated and revealed multiform PVCs and a non‐­sustained polymorphic VT. Her sister and mother had a similar history of abnormal cardiac rhythm, however, there was no history of sudden cardiac arrest in her family. Her sister was fine without any medical attention and her mother also delivered totally 5 children without adverse event. She denied her psychological problem. Physical examination revealed only micrognathia. At that time, Andersen‐­Tawil syndrome was suspected according to her unique feature of VAs, autosomal dominant inheritance, and minor dysmorphic feature. Genetic testing confirmed the missense mutations of KCNJ2 with novel mutations including c.557C>G (p.Pro186Arg) and c.436G>C (p.Gly146Arg) in our patient, her sister, and mother. Choice of treatment had been discussed with the patient. Catheter ablation was offered but she denied due to financial issue and no symptom, so medical treatments were given. Firstly, propranolol was given at dose 30 mg daily but the patient was poorly tolerated due to fatigue then it was switched to metoprolol which are well tolerate up to dose of 100 mg daily, however, there was no difference in her VAs assessed by physical examination and random ECG. Eventually, the patient decided to begin pregnancy without taking any medication despite extensive discussion about risk of adverse cardiac event due to her ventricular dysfunction, VAs and a chance of inheritance to her child. During pregnancy, VAs became less frequent. Due to contracted pelvis, we planned elective cesarean section as a route of delivery. However, the labor pain occurred spontaneously together with irregular fetal heart beat, an emergency low transverse cesarean section was performed under spinal anesthesia. She had no episode of malignant VAs which need to be treated with additional treatment. The patient and baby were doing well postdelivery. After delivery, she developed multidirectional VT all the time so we decided to start flecainide 100 mg per day as an additional therapy. 5 months after pregnancy, ECG showed polymorphic PVCs without VT.

Conclusion:

Combination between flecainide and metoprolol effectively suppressed VAs in patient with ATS especially when were used during pregnancy and childbirth.

FIGURE 1 Twelve‐­lead ECG at A. First visit, B. Antepartum time, C. Postpartum time, D. Postpartum time with flecainide

AP19‐­00029

Ventricular tachycardia is commonplace in pacemaker patients with AV block

Seth Goldbarg

New York Presbyterian/Queens, United States

Introduction:

Ventricular tachycardia is often associated with sudden cardiac death. With the advent or remote monitoring for pacemakers, episodes of VT are readily reported to pacemaker monitoring centers, raising awareness of this arrhythmia in the pacemaker population. Several deleterious effects of right ventricular pacing have been previously reported, but the incidence of VT in patients receiving chronic RV pacing has not been defined. Our study investigated the incidence of ventricular arrhythmias in remotely monitored pacemaker patients with high grade AV block.

Methods:

We examined 12 months of remote transmission data from our pacemaker patients whose indication for pacing was high degree AV block and who receive >90% ventricular pacing. We assessed the prevalence and frequency of ventricular tachycardia in these patients, and noted clinical events or actions taken. We also assessed demographics and comorbidities and recorded the most recent LVEF when available.

Result:

Of 386 patients with remotely monitored permanent pacemakers, 114 (29.5%) had high degree AV block with ventricular pacing greater than 90%. Thirty‐­eight patients had high degree AV block and ventricular tachyarrhythmia, representing 33% of the patients with >90% ventricular pacing. As expected, all patients with recorded high ventricular rates had ventricular tachycardia. No episodes of ventricular fibrillation were noted. Three patients (7.9%) had LVEF <35%, two of whom underwent upgrade to CRT. Two patients (5.2%) had episodes of sustained ventricular tachycardia; one patient died of a nonarrhythmic cause and the other was lost to followup. 47% of patients with VT had concomitant sustained atrial arrhythmias.

Conclusion:

Nonsustained ventricular tachycardia seen on remote monitoring is relatively common in patients with pacemakers for high grade AV block, and should prompt review of left ventricular function.

AP19‐­00031

Evaluation of the validity of Shanghai Score System in Japanese patients with early repolarization syndrome

Keisuke Yonezu, Tetsuji Shinohara, Kei Hirota, Ichitaro Abe, Akira Fukui, Hidefumi Akioka, Yasushi Teshima, Kunio Yufu, Mikiko Nakagawa, Naohiko Takahashi

Oita University, Japan

Introduction:

Early repolarization syndrome (ERS) is generally diagnosed in patients who display ER pattern in the inferior and/or lateral leads presenting with aborted cardiac arrest, documented VF, or polymorphic VT. In J‐­wave syndromes expert consensus conference report endorsed by the APHRS (J Arrhythm, 2016), Shanghai Score System was proposed for diagnosis of ERS. However, it remains unclear whether the scoring system is truly effective in predicting VF occurrence in subjects displaying ER pattern. In the present study, therefore, we retrospectively evaluated the validity of Shanghai Scoring System in our Japanese ERS patients.

Methods:

Thirteen consecutive Japanese ERS patients (mean age 46 ± 17 years) with a history of spontaneous VF, who admitted to Oita University Hospital between 2005 and 2018, were retrospectively evaluated. All the patients were implanted with implantable cardioverter‐­defibrillators (ICDs). The patients were scored according to the Shanghai Score System.

Result:

During the follow‐­up period of 50.0 ± 45.2 months (mean ± SD), three patients experienced appropriate shock delivery due to the recurrence of VF after ICD implantation (recurrent VF group). The VF recurrence was observed 11.1 ± 8.7 months after the ICD implantation. In the recurrent VF group, one patient showed augmented amplitude of J‐­waves with horizontal ST‐­segment while the other 2 patients showed dynamic changes in J‐­wave amplitude. In intracardiac electrograms of ICD recordings, short‐­coupled VPCs invariably preceded the development of VF in the recurrent VF groups. The total points of Shanghai Score System in the recurrent VF group were significantly higher than those in the non‐­recurrent VF group (6.7 ± 0.2 vs 4.4 ± 0.6 points, P<.001).

Conclusion:

Results of our Japanese small‐­scale study suggest that Shanghai Scoring System can effectively identify the patients at high risk for VF recurrence in ERS patients. Its usefulness in subjects with ER pattern who do not have a history of lethal ventricular tachyarrhythmia should be further evaluated.

AP19‐­00071

Successful catheter ablation of fascicular ventricular tachycardia originating from posterior papillary muscle: experience in two cases

Susumu Takase, Kazuo Sakamoto, Koutaro Abe, Shunji Hayashidani, Yasushi Mukai, Akiko Chishaki, Hiroyuki Tsutsui

Kyushu University Hospital, Japan

Introduction:

We report two cases of fascicular ventricular tachycardia (FVT) originating from posterior papillary muscle (PM), successfully treated with catheter ablation therapy guided by precise mapping using a PentaRay catheter.

Methods:

The first patient was an 87‐­year‐­old man who was taken to our hospital due to dyspnea and faintness. An electrocardiogram exhibited relatively narrow QRS tachycardia (cycle length = 320 ms) with sharp R wave, and right bundle‐­branch block configuration with right superior axis deviation. Slow injection of verapamil 2.5 mg decelerated the tachycardia, but the tachycardia persisted. Because accompanying congestive heart failure worsened, we terminated the tachycardia by electric shock, and we decided to undertake catheter ablation. The second patient was a 38‐­year‐­old who visited our hospital due to palpitation. His electrocardiogram of ventricular tachycardia also showed the similar characteristics to the former one, and we undertook catheter ablation.

Result:

In both cases, tachycardia was induced by burst pacing from RV septum, and atrioventricular dissociation was confirmed. Progressive fusion during RV entrainment pacing with variable cycle length was observed. In the first case, because mitral valve had been repaired with Mitraclip device, we inserted catheters to the LV with retrograde aortic approach. A linear duodecapolar catheter placed in the LV longitudinally did not record either left posterior fascicle potential (P2) or mid‐­to‐­late diastolic potential (P1), and thus we mapped the LV with PentaRay catheter using CARTO system. After 3D reconstruction of intracardiac echocardiography (ICE) images of the LV and the PMs using CARTO‐­SOUND system, we tagged the sites with P2 during sinus rhythm, and P1 during VT around the posterior PMs. Manipulating the mapping and ablation catheter carefully, we applied radiofrequency energy of 30 W to the site where P1 with subsequent muscle potential was recorded, and FVT was terminated and was never induced. By observing LV with ICE, success site was in the posterior PMs. In the second case, we recorded P1 and P2 with a linear duodecapolar catheter inserted to the LV longitudinally with retrograde aortic approach. We performed additional mapping using PentaRay catheter with trans‐­septal approach, and multiple P1 potentials preceding P2 potentials during VT were recorded around posterior PMs. We applied RF energy to the site where P1 with subsequent muscle potential was recorded, and the FVT was terminated and was never induced. By observing LV with ICE, success site was on the posterior PMs.

Conclusion:

The PentaRay catheter could become a useful tool in mapping and ablation of fascicular ventricular tachycardia originating from PM, which requires a precise mapping along endocardial trabeculations and PMs, three dimensional structures.

AP19‐­00098

A case of ablation to ventricular tachycardia in tetralogy of Fallot Repair with delayed potential as indicator

Takayuki Shimizu, Keijiro Nakamura, Hitoshi Anzai, Masato Nakamura

The department cardiology, Subaru Health Insurance Society Ota Memorial Hospital, Japan

Introduction:

A 43‐­year‐­old woman with tetralogy of Fallot was admitted to our institution because of sustained VT episodes. She was surgically corrected at the age of four with the standard radical technique that includes patch of the perimembranous ventricular septal defect, and extension of the right ventricular out flow (RVOT) with patch. The ECG during ongoing VT showed a complex with right bundle branch morphology and inferior axis deviation with a heart rate of 221 bpm, and atrioventricular dissociation.

Methods:

The approach was performed from the right femoral vein, and intracardiac mapping was performed using an electrode catheter.

Result:

Using the CARTO system, a voltage map of the right ventricle was created under sinus rhythm, and a voltage map showed a low potential region in the RVOT, which was considered as a surgical scar. In addition, the delayed potential was recorded along the edge of the patch in RVOT. The nonclinical unstable VT was induced after programmed stimulation. We delivered radiofrequency ablation in the delayed potential due to the nonclinical unstable VT. It was difficult to delivery ablation catheter to the delayed potential point for right ventricular enlargement with tetralogy of Fallot. The deep engage of catheter sheath enabled to delivery ablation catheter. After complication of ablation, pacing waveform change in the outflow tract confirmed. The VT was not induced after programmed stimulation.

Conclusion:

The patient remained symptom‐­free and no tachycardia episodes reoccurred during 6 months follow‐­up.

AP19‐­00133

Weathering an adenosine insensitive right ventricular outflow tract ventricular tachycardia (ado insensitive RVOT VT) storm in an adolescent female: a case report

Jose Eduardo Duya

University of the Philippines ‐­ Philippine General Hospital, Philippines

Introduction:

Ventricular tachycardias(VT) are commonly associated with structural heart disease. However, 10% of VTs have no identifiable cause. RVOT‐­VT, a small subgroup of idiopathic VTs localized in the right ventricular outflow tract is highly sensitive to adenosine (ADO). Only 11% of RVOT‐­VT is ADO‐­insensitive, posing a diagnostic challenge. We present a peculiar case of an ADO‐­insensitive RVOT‐­VT storm and the challenges of recognizing and managing it in a resource‐­limited setting.

Methods:

A 15‐­year‐­old female, asthmatic, complained of palpitations, lightheadedness, chest pain and dyspnea a few hours prior to admission. She had a similar episode a month ago, which necessitated ER admission, electrical cardioversion and amiodarone. On admission, she was tachycardic but normotensive. She had diffuse wheezes. Cardiac exam was normal. ECG revealed a wide complex tachycardia (WCT). Work‐­up revealed a normal chest x‐­ray, thyroid function tests and electrolytes. Echocardiogram showed a structurally normal heart. She was managed as a case of viral myocarditis and SVT with aberrancy. Vagal maneuvers and adenosine was given which slowed down the tachycardia. She was then started on IV anti‐­arrhythmics however, sustained symptomatic VT recurred on the same day. ECG analysis showed a WCT, LBBB, AV dissociation with positive QRS complexes in inferior leads suggestive of VT originating from the RVOT. RVOT‐­VT storm was considered and adenosine (maximum dose) was given. The patient did not revert to sinus, hence, ADO‐­insensitive RVOT‐­VT was considered. Cardioversion terminated the VT storm.

Result:

She was managed as a case of viral myocarditis and SVT with aberrancy. Vagal maneuvers and adenosine was given which slowed down the tachycardia. She was then started on IV anti‐­arrhythmics however, sustained symptomatic VT recurred on the same day. ECG analysis showed a WCT, LBBB, AV dissociation with positive QRS complexes in inferior leads suggestive of VT originating from the RVOT. RVOT‐­VT storm was considered and adenosine (maximum dose) was given. The patient did not revert to sinus, hence, ADO‐­insensitive RVOT‐­VT was considered. Cardioversion terminated the VT storm.

Conclusion:

This case report highlights 2 things. The ECG remains a reliable tool in recognizing and localizing VTs clinically. Secondly, it highlights the importance of prompt recognition of ADO‐­insensitive RVOT‐­VT because its management and prognosis is very different from the common causes of VT.

AP19‐­00149

Outcome of rescue ablation in patients with refractory ventricular electrical storm requiring mechanical circulation support

Fa‐Po Chung, Ying‐Chieh Liao, Yenn‐Jiang Lin, Shih‐Lin Chang, Li‐Wei Lo, Yu‐Feng Hu, Ta‐Chuan Tuan, Tze‐Fan Chao, Jo‐Nan Liao, Chin‐Yu Lin, Ting‐Yung Chang, Jennifer Jeanne Vicera, Chye‐Gen Chin, Cheng‐I Wu, Chih‐Min Liu, Shih‐Ann Chen

Heart Rhythm Center and Division of Cardiology, Department of Medicine, Taipei Veterans General Hosp, Taiwan

Introduction:

The management of refractory electrical storm (ES) requiring mechanical circulation support remains clinical challenging in structural heart disease (SHD).

Methods:

A total of 81 patients (mean age: 55.3 ± 18.9, 73 men [90.1%]) undergoing ablation were investigated, including 26 patients with ES requiring circulation support (Group 1) and 55 patients without (Group2). The 30‐­day and 1‐­year outcome, including mortality and recurrent ventricular tachyarrhythmias receiving appropriate implantable cardioverter defibrillators (ICD) therapies, were assessed.

Result:

The patients in Group 1 were characterized by older age, more ischemic cardiomyopathies, worse left ventricular ejection fraction and more comorbidities. Thirty days after ablation, overall events were seen in 15 patients, including pumping failure‐­related mortality in 6 of 10 patients (60%). During a 30‐­day follow‐­up, Kaplan‐­Meier curve demonstrated higher mortality in group 1 than those in group 2 (P < .001). After 1‐­year follow‐­up, in spite of the higher mortality in group 1 (P < .001), the overall events and VA recurrences were similar between these two groups (P = .154 and P = .466, respectively). There was a significant reduction of VA burden in both groups and 2 patients had recurrent ES.

Conclusion:

Higher 30‐­day mortality was observed in patients undergoing rescue ablation for refractory ES requiring circulation support, and pumping failure was the major cause of peri‐­procedural death. Rescue ablation successfully prevented VA recurrences and resulted in comparable 1‐­year prognosis between ES with and without circulation support.

AP19‐­00155

The efficacy of radiofrequency catheter ablation for menstruation‐­dependent incessant ventricular tachycardia: A case report

Takashi Okajima, Hajime Imai, Kenji Arai, Nariko Tsukamoto, Kei Okabe, Yosuke Murase, Naoaki Kano, Motoharu Hayashi, Yasuhiro Ogawa, Katsuhiro Kawaguchi, Toyoaki Murohara

Komaki City Hospital, Japan

Introduction:

Menstrual cycles have been known to affect some arrhythmias. However, there are few reports about the relationship between menstrual cycle and incessant idiopathic ventricular tachycardia (VT).

Methods:

Here we report a case of menstruation‐­dependent incessant VT which was successfully treated by catheter ablation.

Result:

A 41‐­year‐­old woman with periodic palpitations, which always occurred just before and at the beginning of menstruation, was referred to our department. Her electrocardiogram showed incessant non‐­sustained monomorphic VT with inferior axis, left bundle branch block, and R/S transition in lead V3 and notched QRS in inferior leads during the episodes of palpitations. We performed the first session of catheter ablation in the middle of the menstruation phase to avoid heavy menstrual bleeding. Her VT was inducible by intravenous isoproterenol infusion and eliminated by radiofrequency application at the earliest activation site in the posterior free wall of the right ventricular outflow tract. However, her VT recurred just before the next menstrual period. We performed the second session of catheter ablation on the day her menstruation began. Her VT was of the spontaneous incessant type and we found the earliest activation point located near the site where we performed RF application in the first session. We successfully eliminated her VT and she was free from any symptoms for 6 months.

Conclusion:

Idiopathic VT can be incessant during the menstrual cycle. We should be aware that some arrhythmias in premenopausal women can be affected by their menstrual cycles. Radiofrequency catheter ablation performed during the most inducible period of the menstrual cycle is an effective treatment for menstruation‐­dependent incessant VT.

AP19‐­00156

Moderator band VT

Ramdeo Yadave

Batra Hospital , India

Introduction:

Thirty two year old male presented with recurrent pre‐­syncope and palpitations.

Methods:

ECG showed VPCs with LBBB and LAD with late transition after V4. 24 hours Holter showed frequent VPCs and NSVT and couplets and triplets with 42% VPCs load. Echo showed structurally and functionally normal heart. MRI of heart showed no late gadolinium enhancement. PET CT was done by Dr.Narsimhan Sir.which was normal. Put on Amiodarone 200 twice daily along with Metoprolol 25 mg twice daily. Repeat Holter after 3 weeks of medications VPCs reduced to 5%. Patient is asymptomatic on medical therapy. He did not agreed for EPS and RFA. Recommended for ICD implantation.

Result:

The morphology of VPCs suggestive of Moderator band VT. This may degenerate to VF. ICD should be recommended for this. This VT can be ablated from either septal part of moderator band or lateral part of it at the attachment of MB to anterior papillary muscle of RV.

Conclusion:

Moderator band VT is dangerous as it may degenerate into VF and ICD support may be needed. RFA is the treatment of choice.

AP19‐­00196

Recurrent occurrence of ventricular tachycardia after extubation undergoing bile duct resection, Roux‐­en‐­Y hepaticojejunostomy in young patient

Ilsang Han, Youngjoon Shin

Ulsan University Hospital, South Korea

Introduction:

Arrhythmia is a common complication that can occur during surgery and is sometimes a serious complication that can be life threatening. Arrhythmia occurring during surgery are mostly benign and improve without special treatment, but sometimes life threatening and poor vital signs may require immediate antiarrhythmic or electrotherapy. In some cases, permanent arrhythmia may require continued treatment after surgery.

Methods:

A 28‐­year‐­old man (height 156.3 cm, weight 60.5 kg) undergoing bile duct resection, Roux‐­ en‐­Y hepaticojejunostomy due to cholelithiasis with cholecystitis, choledocholithiasis. He diagnosed mental retardation level 2. Pre‐­operation laboratory test is normal except liver function test (AST 64, ALT 141). And electrocardiography shows heart rate 57 bpm, sinus rhythm, first degree AV block and echocardiography shows LVEF 67%, normal echo. When we prepared extubation after finishing operation, oxygen saturation was low at 85%. So we started manual ventilation for oxygenation and saturation was increased at 100%. When we extubated endotracheal tube, his ECG changed NSR to monomorphic VT. Firstly we considered that is PSVT and infused adenosine 6 mg twice and 12 mg once. But arrhythmia was continuous and vital sign changed unstable. Finally we performed reintubation and defibrillated at 200 J. After defibrillation, arrhythmia converted normal sinus rhythm. We transferred the patient to the ICU and evaluated further to see if the patient had heart problems.

Result:

The patient attempted extubation several times in ICU, but failed with repeated VT every time. We tried echocardiography after operation and consulted with a cardiologist. The result of echocardiography is normal. The cardiologist concluded that arrhythmia is idiopathic VT due to catecholamine surge, and recommended to use a esmolol. Finally we tried to extubate after sedation using dexmedetomidine and beta‐­blocker, and succeeded.

Conclusion:

During anesthesia, a wide variety of arrhythmias can occur and VT is one of the arrhythmias that can be life threatening and requires immediate attention. Ventricular tachycardia during anesthesia can be caused by various causes. We struggled to find a cause of VT in the patient. But there was no structural and functional abnormalities in the patient's heart. His ECG pattern is a monomorphic VT with LBBB. Moreover VT usually occurs in irritating conditions such as light anesthesia or extubation. So we concluded that patients VT pattern is idiopathic VT. Idiopathic VT can occur in young patients without underlying disease. Therefore, an anesthesiologist should be familiar with the diagnosis and treatment of an idiopathic VT, so that if a monomorphic VT occurs during anesthesia in a young healthy patient, it should be able to be treated appropriately without embarrassment.

AP19‐­00227

A case of successful ablation of idiopathic nonsustained ventricular tachycardia originating from the left ventricular summit through left ventricular outflow tract

Minh Hai Dang

Vietnam Heart Association, Vietnam

Introduction:

The summit of left ventricle (LV) is the most superior portion of the epicardial LV bounded by an arc from the left anterior descending coronary artery, superior to the first septal perforating branch to the left circumflex coronary artery. Some patients may not be able to ablate ventricular tachycardia through grate cardiac vein (GCV) or the epicardium. A successful radiofrequency catheter ablation of a patient suffers from nonsustained LV summit ventricular tachycardia through left ventricular outflow tract (LVOT) was reported in this paper.

Methods:

Sixty‐­four‐­year‐­old woman with a complaint of chest discomfort and palpitation. She presented to her local hospital with symptoms, and a 12‐­lead electrocardiogram (ECG) showed a nonsustained ventricular tachycardia (NSVT), wide QRS‐­complex tachycardia with left bundle branch block morphology and a right inferior axis in the frontal plane, preserved LV systolic function (EF: 51%), transition V2‐­>V3, large R in V1, larger R‐­wave amplitude in III than in II lead and a deeper Q wave in aVL than in aVR lead.

Result:

During programmed procedure appeared couplet and bigeminy premature ventricular contractions (PVC). The earliest activation with low‐­amplitude potential was identified at the Great Cardiac Vein (GCV) located in inaccessible area of LV summit and preceded the QRS onset by 33 ms. QRS morphology of pace mapping was similar original PVC. Unfortunately, this position had high impedance (200 Ω). In right ventricular outflow tract mapping during PVC, the earliest potential (13 ms preceding the onset of QRS complex) was recorded at the posteromedial septum of RVOT. (We continued mapping in left ventricular outflow tract), During LVOT mapping procedure, the earliest activation potential position that description of the fusion patterns between the left coronary cusp (LCC) and noncoronary cusp (NCC) preceded the QRS onset 15 ms. Coronary angiography was done to determine ablation catheter with coronary arteries. After the application of radiofrequency (RF) energies, the PVC was terminated during RF ablation at the site of the between LCC and NCC potential 15 msec preceding the onset of the QRS complex. The PVC was not recurred during following period.

Conclusion:

This study revealed that the LV summit VT could be eliminated by a direct approach GCV branch running below the proximal left coronary arteries and a remote approach from the adjacent endocardial sites

AP19‐­00228

Substrate modification for refractory VT storm and multiple aicd shocks in 3 different etiologies (post‐­myocardial infarction, granulomatous myocarditis and ARVD)

Saurabh Kapadia, Saurabh Dhariya, Ameya Udayvar, Ashwin Mehta

Jaslok Hospital, Mumbai, India

Introduction:

Catheter ablation is an effective therapeutic option in the management of recurrent VT. Radiofrequency ablation is preferred as salvage therapy in patient with VT storms and multiple implantable defibrillator shocks who have failed medical therapy. Substrate mapping for scar location and ablation strategy in sinus rhythm targeting the slow conduction zones/critical isthmus allows us to offer ablation therapy to patients with unmappable VT. Various ablation strategies such as targeting late potentials (LP), endo‐­and epicardial scar homogenization ,and eliminating local abnormal ventricular activities (LAVA) are known. We describe our experience of substrate modification in three different categories of patient

Methods:

N.A

Result:

Post MI: 63 years old male presented late with Anterior wall MI (killip class III) Managed with optimal medical therapy(LAD territory was non viable). He had recurrent VT reverted with electrical cardioversion and not responding to pharmacological measures. Due to his refractory VT storm, 3D‐­mapping & ablation was carried out with the Carto system. High density voltage 3D‐­map of the LV was created with around 300 points.Scar areas were defined as voltages <0.5 mV. Subsequently, voltages were reduced by 0.1 mV to map islands of high voltage in and around the scar. Areas of LP were marked & annotated. RF ablation was delivered with a 3.5 mm, irrigated catheter in areas of slow conduction (LP) around the Scar. Majority of the areas were around the apical, posterior apex & apical septum. Recurrent episodes of VT subsided. Granulomatous affection: 55 years old man with prior history of undiagnosed cardiomyopathy EF‐­20% since 3 years & AICD implantation, presented with VT storms and multiple ICD shocks. Initially VT were terminated by Antitachycardia pacing but were unresponsive to antiarrthymics. EPS & 3D mapping showed free wall VT. Since he had 3 morphologies of VT, we did substrate modification. This terminated the VT storms. Cervical lymph node biopsy showed necrotizing granulomatous lymphadenitis likely mycobacterial etiology. Cardiac MRI showed no LGE. Started on antitubercular drugs. ARVD: A 43 years old male diagnosed case of ARVD on MRI, underwent AICD Implantation in Jan 2019. He presented with VT storm and multiple ICD shocks with AICD battery depleted in just 1 month. Electrophysiological study (EPS) showed two induced forms of VT morphology. Due to the prevalence of epicardial scarring in ARVD, substrate modification was done through both endocardial and epicardial access. It showed large scar areas towards RV free wall. The patient has no VT after that and has been doing well.

Conclusion:

Substrate modification should be considered early in treating patient with refractory VT storm and multiple AICD shocks.

AP19‐­00248

Utility of novel Omnipolar activation maps for the detection of ventricular premature contraction origin

Shingo Maeda, Mihoko Kawabata, Fusae Doi, Tomokazu Chijimi, Yasuhide Tsuda, Hirotsugu Atarashi, Kenzo Hirao

AOI Universal Hospital, Japan

Introduction:

Bipolar electrograms are significantly influenced by direction of the propagating wavefront in relation to the recording bipole. Omnipolar voltage mapping (Advisor™ HD Grid, EnSite Precision™, Abbott Medical, USA) may be superior to standard bipolar mapping since it obtains maximum voltage of all possible bipolar electrode orientations without the need for catheter rotation. Whether omnipolar activation maps also describe better activation maps vs traditional bipolar maps during ventricular premature contraction (VPC) catheter ablation is unclear.

Methods:

N/A

Result:

A 71‐­year‐­old male with symptomatic drug‐­refractory VPCs was admitted for catheter ablation. An Advisor™ HD Grid ‘‘Super’’ high‐­density mapping catheter was advanced to the right ventricular outflow tract. 3D electroanatomical mapping was performed with the Advisor™ HD Grid catheter (4 mm interelectrode spacing along and across the catheter splines) and a high‐­resolution activation map was created. Bipoles were calculated along (MAP 2), across (MAP 3) and bidirectional (MAP 4) the splines while omnipoles (MAP 1) were derived from a right triangle clique. Within a square area, four omnipolar and two bipolar values along, across and bidirectional values were defined. Though the earliest activation site was vague by along and across maps (arrow), white color became evident by bidirectional map, and the VPC origin became distinct with omnipolar mapping. RF lesions were given via an open‐­irrigated ablation catheter (TactiCath™ Quartz Ablation Catheter, Abbott Medical) targeting a lesion size index 5.0. The VPC was eliminated by first radiofrequency ablation.

Conclusion:

Omnipolar activation mapping may be more accurate than traditional bipolar mapping during ventricular premature contraction (VPC) catheter ablation.

AP19‐­00318

Chronic obstructive pulmonary disease as an independent risk factor of lethal ventricular arrythmia: A Nationwide Population‐­Based study

Chun Chao Chen, Yu Ann Fang, Li Ching Sung, Ju Chi Liu

Shuang Ho Hospital, Taiwan

Introduction:

The incidence of lethal ventricular arrhythmia (VA) in patients with chronic obstructive pulmonary disease (COPD) is still unclear.

Methods:

We used the data of National Health Insurance Research Database (NHIRD) from January 1st, 2001 (index date) to December 31th 2012. Totally 143 676 patients were comprised and were divided into 2 groups (COPD and without COPD), matched by gender and age. The incidence and risks were assessed during the follow‐­up period.

Result:

Patients with COPD had higher incidence rate of lethal VA compared with patients without COPD [adjust hazard ratio (aHR) 1.45; 95% confidence interval (CI):1.25‐­1.68] after adjusting the comorbidities, medications, level of urbanization and monthly income. The times of hospitalization or emergency visit because of acute exacerbation of COPD cause higher risk of lethal VA [aHR: 1.28 (95% CI: 1.08‐­1.50), 1.75 (95% CI: 1.32‐­2.32), 1.88 (95% CI: 1.46‐­2.41) for 1st, 2nd and 3rd time respectively]. The patients with asthma‐­COPD overlap syndrome (ACOS) had higher risk of lethal VA than patients with COPD only [aHR: 1.49 (95% CI: 1.25‐­1.79), 1.32 (95% CI: 1.11‐­1.57) respectively]. With higher CHA2DS2‐­VASc and ORBIT score, the risk of lethal VA elevated.

Conclusion:

Patients with COPD had higher risk of lethal VA and is worsened by acute exacerbation of COPD, mix‐­type air way disease.

AP19‐­00349

Noninvasive SAECG analysis predicts epicardial ablation approach in arrhythmogenic right ventricular cardiomyopathy

Ankit jain, Fa‐Po Chung

Taipei Veterans General Hospital, India

Introduction:

This study investigated the feasibility of using the SAECG in the identification of arrhythmogenic substrate in arrhythmogenic right ventricular cardiomyopathy (ARVC) requiring right ventricular (RV) epicardial approach.

Methods:

Ninety‐­three definite ARVC patients with drug refractory VT were enrolled and reclassified into 2 groups: definite ARVC with successful RV endocardial ablation only (Group 1), definite ARVC with RV epicardial ablation in addition to RV endocardial ablation (Group 2). Baseline characteristics and non‐­invasive parameters including SAECG were compared.

Result:

The groups 2 patients were male predominant, had a worse RV function, higher incidence of syncope and fatal ventricular arrhythmia, and more depolarization abnormality. The Group 2 patients fulfilled more SAECG criteria than Group 1 (2.5 ± 0.8 vs 1.0 ± 0.7, P < .001). After multivariate analysis, independent predictors of epicardial ablation include the numbers of fulfilling SAECG criteria (Odds ratio [OR]: 3.3, 95% confidence interval [CI]: 1.6‐­6.7, P = .001), men (OR: 6.8, 95% CI: 0.9‐­1.1, P = .033) and syncope (OR: 8.6, 95% CI: 0.9‐­38.8, P = .005). Additionally, the patient fulfilled more SAECG criteria was associated with larger RV endocardial unipolar low‐­voltage zone (LVZ) percentage (P < .001), larger RV epicardial bipolar LVZ percentage (P = .020), and longer RV endocardial and epicardial activation time (P < .001 and P = .006)

Conclusion:

The number of fulfilled SAECG criteria was associated with epicardial substrate and could identify the potential requirement of the epicardial approach in ARVC patients with drug refractory VA.

AP19‐­00374

Merging three‐­dimensional CT with electroanatomical mapping facilitates mapping and ablation of ventricular arrhythmias originating from aortic root

Song Zou, Ruikun Jia, Kaijun Cui

West China Hospital of Sichuan University, China

Introduction:

When radiofrequency ablation is performed in aortic root, angiography is traditionally recommended to avoid injury of coronary arteries. However, this strategy cannot real time monitor distance from coronary ostia to catheter tip if catheter is moved and increases exposure to X‐­ray. To avert limitations mentioned above, we introduce an alternative approach to intuitively show special location of ablation catheter and coronary arteries by integrating three‐­dimensional CT (3D‐­CT) and electroanatomical mapping (EAM) in mutual‐­perpendicular planes (PA and LL views).

Methods:

12 patients (49.7 ± 15.0 years old, 5 men) were prospectively recruited. Among them, ventricular arrhythmias (VAs) originated from left coronary cusp (LCC) in 9 patients, right coronary cusp (RCC) in 1 patient and junction between left and right coronary cusps (LCC‐­RCC) in 2 patients. Before mapping and ablation, we merged 3D‐­CT with EAM to monitor distance between coronary ostia and catheter tip.

Result:

Ablation got acute success in all patients including 7 patients (5 LCC‐­originating cases and 2 LCC‐­RCC‐­originating cases) without coronary angiography and 5 patients (4 LCC‐­originating cases and 1 RCC‐­originating case) needing additional coronary angiography. No complication and technical difficulty occurred during operation.

Conclusion:

Integration of 3D‐­CT and EAM facilitates mapping and ablation in aortic root, especially in LCC‐­originating and LCC‐­RCC‐­originating cases.

FIGURE 1 Integration steps of 3D‐­CT and electroanatomical mapping (EAM). Firstly, 3D‐­CT is introduced in PA plane (Panel A) and merged with EAM (Panel B), then overlap them in LL plane (Panel C and D).

AP19‐­00389

Ablation for incessant idiopathic accelerated idioventricular rhythm

Ulhas M Pandurangi, Radhika B, Kotti K, Jaya Pradhap, Aishwarya S, Sabari S, Mahima P Manoj, Nithin G, Sailendri G, Benjamin S, Ravi Kumar, Nirmala S, Dasari Himaja, Sandini S, Swathi K

The Madras Medical Mission, India

Introduction:

Accelerated Idioventricular Rhythm (AIVR) is usually asymptomatic and is a marker of coronary reperfusion, structural heart disease or drug overdosage. We report a successful radio frequency ablation (RFA) for a rare case of incessant, symptomatic and drug refractory idiopathic AIVR arising from the left posterior fascicle (LPF) near the apical septum. Successful RFA brought symptomatic relief by restoration of atrioventricular (AV) synchrony in sinus rhythm.

Methods:

A 50‐­year‐­old female with no known comorbidities presented with recurrent palpitations associated with giddiness and shortness of breath of 3 months duration. The 12‐­lead ECG (Figure 1) suggested AIVR at rate of 85 BPM with isorhythmic AV dissociation. The R wave in V1, RS in V6, superior axis and relatively narrow QRS complexes indicated the origin from the LPF region. Her echocardiogram, contrast enhanced cardiac MRI and coronary angiogram were normal. A 24‐­hour Holter (Figure 2) revealed incessant AIVR. She was on metoprolol succinate 50 mg OD and amiodarone 200 mg OD.

Result:

Under conscious sedation a standard invasive electrophysiology study was performed. Incessant AIVR with stable hemodynamics was observed. Atrial overdrive pacing (AOD) confirmed normal AV conduction. The AIVR reinitiated immediately after AOD and ventricular overdrive pacing. Adenosine (12 mg IV), metoprolol (10 mg IV) and verapamil (10 mg IV) did not influence AIVR. The ventricular rate accelerated during isoprenaline infusion. A 8F Abbott FlexAbility^TM irrigated bidirectional ablation catheter was used to map the left ventricle by retrograde aortic approach under fluoroscopy (7.5 FPS). At a site near the apical septum posteriorly where sharp potentials preceding the onset of QRS on ECG by 30 ms were found, unipolar recording showed QS pattern (Figure 3) and where pace mapping was of satisfactory match (Figure 4) a single RF energy (40 W, 50°C) resulted in cessation of AIVR in 3 seconds (Figures 5 and 6). The energy was continued for total of 120 seconds. The AIVR did not recur even on isoprenaline. At 6 months of follow‐­up (Figure 7) patient remained asymptomatic in sinus rhythm.

Conclusion:

Rarely AIVR can occur in normal heart and gives rise to symptoms despite slow ventricular rate. It can be resistant to multiple drugs. It can be effectively cured by RFA.

AP19‐­00393

Clinical characteristics and outcomes of catheter ablation for ventricular tachycardia in cardiac sarcoidosis: Significant role of aneurysm for arrhythmogenic substrate

Keita Mamiya, Yasuya Inden, Toshifumi Nakagomi, Koichi Furui, Shuro Riku, Kazumasa Suga, Hiroya Okamoto, Toshiro Tomomatsu, Aya Fujii, Satoshi Yanagisawa, Rei Shibata, Toyoaki Murohara

Nagoya University Graduate School of Medicine, Japan

Introduction:

Ventricular tachycardia (VT) in patients with cardiac sarcoidosis is commonly observed. However, data of the catheter ablation for VT is limited. The purpose of this study was to evaluate the characteristics and outcomes of catheter ablation for VT in patients with cardiac sarcoidosis.

Methods:

Eleven patients with a diagnosis of cardiac sarcoidosis based on the guidelines for Diagnosis and Treatment of Cardiac Sarcoidosis (The Japanese Circulation Society 2016) who underwent catheter ablation for VT were included. Endocardial radiofrequency ablation was initially performed in all patients (right ventricular in 3 patients, left ventricular in 8).

Result:

All patients (mean age 60.8 ± 11.8 years) received antiarrhythmic drugs (mean 2.0 ± 1.1 drugs) before the ablation. The mean left ventricular ejection fraction was 34.8 ± 14.6%. Eight patients (73%) had an aneurysm detected with the echocardiography or left/right ventriculography; and 6 patients showed an extended low‐­voltage area (LVA) within the aneurysm. In the 5 patients who underwent enhanced cardiac magnetic resonance imaging, delayed enhancement in aneurysm was observed in each patients. The mean 2.7 ± 2.5 VTs (mean cycle length 408 ± 81 ms) were induced during the electrophysiologic study. The scar‐­related VT within the aneurysm was identified in all patients with aneurysm and LVA. The VT‐­free survival rate after the first procedure was 45% at the 6‐­month follow‐­up. Four patients underwent a second procedure, and 3 of 4 patients had no‐­VT recurrence. One patient required a third ablation by epicardial approach.

Conclusion:

Management of VT in patients with cardiac sarcoidosis was difficult, although catheter ablation was effective in some patients. The presence of the aneurysm can be a potential arrhythmogenic substrate for VT occurrence in cardiac sarcoidosis.

AP19‐­00394

Novel application of 18F‐­fluorodeoxyglucose positron emission tomography/magnetic resonance imaging to assess a patient with frequent non‐­sustained ventricular tachycardia

Chin‐Yu Lin, Yenn‐Jiang Lin, Chih‐Yung Chang, Wen‐Sheng Huang, Shih‐Ann Chen

Taipei Veterans General Hospital, Taiwan

Introduction:

There is growing evidence to prove the clinical implication of contrast‐­enhanced magnetic resonance imaging (MRI) in patients with ventricular arrhythmia (VA). 18F‐­fluorodeoxyglucose positron emission tomography (FDG‐­PET) has a well‐­established role in detecting inflammation.

Methods:

N/A

Result:

A 28‐­year‐­old female was referred to our hospital due to symptomatic ventricular arrhythmia (VA) for 6 months. A simultaneous 18F‐­fluorodeoxyglucose (FDG) positron emission tomography/contrast‐­enhanced magnetic resonance imaging (PET/MRI) imaging (SIGNA™ 3.0T PETMR, GE Healthcare) was performed before a further interventional procedure, showing late gadolinium enhancement (LGE) and increased FDG uptake, each in the LV mid to apical inferior septum and in the mid to the apical inferior free wall. Three‐­dimensional LV endocardial was created using Carto 3 (Biosense Webster, Inc.) with a 3.5 mm irrigated tip catheter (Thermocool, Biosense Webster, Inc.). LV endocardial bipolar revealed low‐­voltage zone (LVZ) in the inferior wall, which was corresponding to LGE area and origin of first inducible ventricular tachycardia. The second identified VT was identified within the FDF uptake area, which was within the normal bipolar voltage area. Catheter ablation achieved negative inducibility during procedure. Occasional isolated PVC recurrence was noticed with morphology like the second VT. Under the impression of inflammatory related VA as based on the FDG‐­PET, prednisolone 10 mg per day has been prescribed for 2 months and then tapered. The PVC burden decreased to less than 1 % after the medical management.

Conclusion:

The simultaneous PET and MRI scan identify the NSVT origin and the inflammatory nature of this patients.

AP19‐­00397

Refractory ventricular fibrillation caused by caffeine intoxication

Shuro Riku, Yasuya Inden, Satoshi Yanagisawa, Toshifumi Nakagomi, Koichi Furui, Kazumasa Suga, Keita Mamiya, Hiroya Okamoto, Toshiro Tomomatsu, Aya Fujii, Toyoaki Murohara

Nagoya University Graduate School of Medicine, Japan

Introduction:

It is broadly believed that caffeine can exert cardiotoxicity at overdose ntakes. Several reports have described cardiac arrest or acute arrhythmia in individuals with caffeine intoxication. However, clinical observations on patients with pure caffeine intoxication have been strongly limited, hence its cardiotoxicity remains to be elucidated. Here, we provide the first report of a female who took caffeine tablets and presented with refractory ventricular fibrillation (VF).

Methods:

The patient was a 30‐­year‐­old Japanese woman with no significant personal or family medical history. She had taken 120 tablets of over‐­the‐­counter caffeine products, containing 100 mg of caffeine each, in her room. One or two hours after the intake, she vomited and then had a generalized seizure. Her family found her and called an ambulance. On the way to the hospital, she went into cardiopulmonary arrest associated with recurrent VFs. After two instances of shocks with an automated external defibrillator, her rhythm changed to pulseless electrical activity. However, VFs recurred in the emergency department, and three more rounds of 150‐­J biphasic countershocks achieved a recovery to spontaneous circulation. A 12 lead‐­electrocardiogram (ECG) after the defibrillation showed a sinus tachycardia with multiple supraventricular premature contractions and diffuse T wave inversions. Considering the refractory nature of VFs in this patient, we introduced percutaneous cardiopulmonary support (PCPS). No further VFs recurred after the introduction of these therapies. ECG revealed a sinus tachycardia with heart rate between 100 and 140 beats/min and frequent ventricular premature contractions for the initial 10 hours. This then changed to QTc interval prolongation, greater than 630 ms, and diffuse notched T waves, which resolved to normal on the 10th day. A transthoracic echocardiography and coronary angiography revealed no abnormalities on the valves or wall motions and no stenosis of the coronary arteries, respectively. The PCPS was successfully removed 4 days after admission.

Result:

After a recovery of consciousness, she documented an overdose intake of caffeine tablet obtained via internet for a suicidal purpose. A blood examination, which was sampled at the emergency room, revealed an elevated caffeine concentration of 172 mg/L. She was discharged to her home 16 days after admission without any physical deficits. Exercise tolerance test performed after discharge did not induce any arrhythmias. Ultimately, we confirmed caffeine intoxication caused VFs and subsequent complications.

Conclusion:

We have detailed the potentially lethal arrhythmogenesis of caffeine in a human case. Intensive treatments against refractory arrhythmia may have an impact upon the prognosis of patients with caffeine intoxication. Further discussions are needed to prevent intoxication with caffeine, which is available unrestricted.

AP19‐­00399

Successful catheter ablation for polymorphic ventricular tachycardia guided by 12‐­lead 24‐­hour Holter electrocardiography

Kotaro Fukumoto, Shin Kashimura, Koji Negishi

Yokohama Municipal Citizen's Hospital, Japan

Introduction:

N/A

Methods:

N/A

Result:

A 58‐­year‐­old female with syncope was taken to our hospital and was observed with continuous electrocardiographic monitoring. Premature ventricular contractions (PVCs) with identical morphology followed by polymorphic ventricular tachycardia (VT) sporadically occurred. The clinical PVC and VT were not recorded in 12‐­lead but in one‐­lead electrocardiography (ECG). Although detailed waveforms of the arrhythmia were uncertain, catheter ablation targeting the identical PVC triggering polymorphic VT was conducted. Despite repeated induction pacing protocols with and without isoproterenol and adenosine triphosphate, the target PVC could never be induced during procedure and the session ended without radiofrequency application. One year later, syncopal episodes recurred and she was readmitted to our hospital. In order to detect the arrhythmia events causing syncope, 12‐­lead 24‐­hour Holter ambulatory ECG was performed and the data were urgently analyzed. The Holter recording revealed the clinical VT initiating with the identical PVC, which was thought to originate from inferior right ventricle. After data analysis of the Holter ECG, catheter ablation was conducted. Just like in the first ablation session, clinical arrhythmia was never induced in spite of earnest efforts at induction maneuvers. Therefore, using the result of 12‐­lead 24‐­hour Holter ECG as a guide, we performed pace‐­mapping. A QRS configuration of the paced beat from the inferior site of the right ventricle was almost identical to that of the target PVC recorded in the Holter ECG (Figure). Radiofrequency energy was delivered to the site with good pace‐­map and its adjacent region (Figure). She discharged without an implantable cardioverter defibrillator or antiarrhythmic agents and has had no episode of syncope or palpitation until now.

Conclusion:

We experienced a case with polymorphic VT triggered by PVC which was successfully ablated with 12‐­lead Holter ECG as a guide.

AP19‐­00405

High‐­density mapping is useful to identify the circuit of ventricular tachycardia: A case report of the experience of using HD‐­Grid catheter

Yui Nakayama, Hisao Matsuda, Akira Kasagawa, Kasahara Mizuho, Marika Yamada, Kazuaki Okuyama, Norio Suzuki, Kei Mizukoshi, Makoto Takano, Ikutaro Nakajima, Toshiyuki Furukawa, Hidekazu Miyazaki, Koichi Mizuno, Harada Tomoo, Yoshihiro Akashi

St. Marianna University School of Medicine, Yokohama‐­City Seibu Hospital, Japan

Introduction:

Advances in 3D mapping systems have made it possible to visualize high density (HD) intracardiac potentials, which help identify the circuit of arrhythmias. We report a case in which a 3D mapping system was useful to identify the reentrant circuit of ventricular tachycardia (VT) in a patient with cardiac sarcoidosis.

Methods:

A 59 years old female with cardiac sarcoidosis who had been implanted a pacemaker for complete atrioventricular block was hospitalized because of severe nausea. The electrocardiogram revealed wide QRS regular tachycardia with 200 bpm. Echocardiography showed high degree of thinning of ventricular septum and the ejection fraction was reduced to 34%. Because her hemodynamic status was unstable, cardioversion was performed and the tachycardia was terminated. Although continuous intravenous administration of Amiodarone was performed, the tachycardia was recurred. She underwent an emergent Electrophysiological Study for further evaluation of the wide QRS tachycardia. The wide QRS tachycardia was diagnosed as VT with confirmation of atrioventricular dissociation. The morphology of QRS was right bundle brunch block type with upper axis, the width of QRS was 129 ms, and the transitional zone was observed in V1 lead. Tachycardia cycle length (TCL) was 412 ms. Because her hemodynamic status was stable, the mapping was performed during VT.

Result:

An electro anatomical mapping system (EnSite Velocity; Abbott) was introduced and the HD mapping was obtained by HD Grid Mapping Catheter (Abbott). An HD Grid catheter was inserted into the left ventricle (LV) with retrograde approach. The voltage map of the LV revealed wide low voltage area at the base of LV, where is consistent with the findings of echocardiography. Mid diastolic potential was recorded at the base of the LV septum, entrainment pacing at this site revealed slight fused QRS configuration and the stimulus QRS time (S‐­QRS) was 44 ms and postpacing interval (PPI) was 435 ms which was judged as an outer loop of VT circuit. An ablation catheter (FlexAbility; Abbott) was located at the same site and radiofrequency catheter ablation (RF) was performed. Although TCL was prolonged to 556 ms, VT was not terminated. The ablation catheter was advanced toward apical slightly, the spiky pre potential was recorded at the tip of the ablation catheter and the unipolar electrogram was QS pattern. Entrainment pacing at this site revealed concealed entrainment and S‐­QRS was 56 ms. This site was diagnosed as the Exit of the VT circuit, and the RF application at this site could terminate the VT within 2 seconds. After the RF, VT could not be induced with any ventricular stimulation.

Conclusion:

HD mapping was useful to identify the VT circuit. We report a case of VT arising from LV in a patient with cardiac sarcoidosis which was successfully ablated using HD mapping with some considerations.

AP19‐­00422

Can machine learning of monophasic action potentials predict long‐­term ventricular arrhythmias?

Anojan Selvalingam, Mahmood I. Alhusseini, Albert J. Rogers, David E. Krummen, Firas Abuzaid, Junaid A.B. Zaman, Tina Baykaner, Paul Clopton, Peter Bailis, Matei Zaharia, Sanjiv M. Narayan

Stanford University, United States

Introduction:

Predicting sustained ventricular tachycardia/fibrillation (VT) is difficult even in patients with coronary disease (CAD), left ventricular (LV) dysfunction and other risk factors. The objective of this study is to train deep neural networks (DNN) on features of monophasic action potentials (MAP) that reflect cellular remodeling. We then tested the hypothesis that deep learning of ventricular MAPs can predict freedom from VT on long‐­term follow‐­up.

Methods:

We studied 26 patients with CAD and left ventricular ejection fraction (LVEF) ≤ 40%, in whom MAPs were recorded at electrophysiological study from right ventricle (RV) and LV (Figure 1A). Voltage‐­time series MAPs were input to the DNN, for the binary output label of ICD therapy (1/0). Training was performed using k‐­cross validation (CV) with k = 7. The network was developed using a total of 3580 MAPs in training and validation cohorts.

Result:

Patients were 62.0 ± 18.7 years old with LVEF 28.0 ± 8.3%. Average follow up duration was 752 ± 493 days. DNN training accuracy converged to 100% (Figure 1B). MAP duration and other parameters did not differ between groups (P = NS). In independent validation cohorts, the trained DNN predicted appropriate ICD therapy with accuracy as high as 78%.

Conclusion:

Deep learning models of ventricular MAPs, which may reflect pathological remodeling, may predict VT‐­freedom on long‐­term follow‐­up. Data from more studies is needed to determine if this approach enables novel risk prediction.

AP19‐­00488

Real‐­world comparison of outcomes among elderly patients with ventricular tachycardia undergoing outpatient catheter ablation procedure with vs without intracardiac echocardiography imaging

Michael Field, Laura Goldstein, Stephanie Hsiao Yu Lee, Iftekhar Kalsekar, Charlene Wong, Rahul Khanna, Matthew Reynolds, Jeffrey Winterfield

Johnson and Johnson Medical Devices, Canada

Introduction:

Intracardiac echocardiography (ICE) use during catheter ablation for ventricular tachycardia (VT) may improve outcomes and reduce complications. This study compared outcomes including 12‐­month readmission, repeat ablation, and 30‐­day complications (cardiac perforation, vascular complications, major bleeding) among elderly ventricular tachycardia (VT) patients with implantable cardioverter defibrillator/cardiac resynchronization therapy (ICD/CRT‐­D) undergoing catheter ablation with ICE compared to without ICE.

Methods:

Using the 2008‐­2017 Centers for Medicare and Medicaid Services (CMS) Standard Analytical Files database, patients aged ≥65 years with a primary diagnosis of VT undergoing outpatient catheter ablation procedure were identified, with the first such ablation classified as index procedure. Patients were classified into ICE and non‐­ICE groups based on the presence or absence of the ICE procedure code during index admission. Patients were required to have continuous enrollment and an ICD/CRT‐­D billing code during the 6‐­month pre‐­index period. A 1:1 propensity score matching using greedy match without replacement technique was performed to match patients in the ICE and non‐­ICE group on study covariates including patient demographic and comorbid characteristics. Time‐­to‐­event analysis including Kaplan‐­Meier log‐­rank test for bivariate comparison and Cox proportional hazards model for risk estimation were used to compare study outcomes among the matched ICE and non‐­ICE patients. Sensitivity analysis was performed by restricting the comparison of outcomes between ICE and non‐­ICE group to patients in whom transseptal puncture was performed during VT ablation.

Result:

A total of 2820 patients were identified based on study criteria (1143 ICE and 1677 non‐­ICE). The mean age was 73 years, with a majority (92%) being male. Based on propensity matching, 1,073 patients in both the ICE and non‐­ICE group were identified. Patients in the ICE group had 24% lower risk of all‐­cause (hazard ratio [HR] 0.76; confidence interval [CI] 0.67‐­0.86), 24% lower risk of cardiovascular (CV)‐­related (HR 0.74; CI 0.66‐­0.87) and 20% lower risk of VT‐­related (HR 0.80; CI 0.67‐­0.98) readmission compared to non‐­ICE patients. No significant difference in repeat ablation or complications was observed among the two groups. In VT ablations with transseptal puncture, ICE patients (n = 231) had 45% lower risk of all‐­cause (HR 0.53; CI 0.41‐­0.68), 57% lower risk of CV‐­related (HR 0.43; CI 0.32‐­0.58) and 57% lower risk of VT‐­related (HR 0.43; CI 0.29‐­0.66) readmissions compared to non‐­ICE patients (n = 231).

Conclusion:

Elderly VT patients with ICD/CRT‐­D undergoing catheter ablation with ICE had lower 12‐­month readmissions compared to non‐­ICE patients.

AP19‐­00496

The effect of bilateral cardiac sympathetic denervation for refractory ventricular tachycardia in ischemic cardiomyopathy – A case report

Yuko Miki, Takehito Sasaki, Yoshinori Okazaki, Wataru Sasaki, Shingo Yoshimura, Shohei Kishi, Mitsuho Inoue, Katsura Niijima, Hiroyuki Motoda, Koji Goto, Yutaka Take, Kohki Nakamura, Shigeto Naito

Gunma Prefectural Cardiovascular Center, Japan

Introduction:

Recent studies have shown that cardiac sympathetic denervation (CSD) is effective treatment for refractory ventricular tachyarrhythmia (VT) in patients with structural heart disease. The objective this case report is to highlight the effect of CSD in suppression of treatment‐­resistant VT.

Methods:

Case report

Result:

A 79‐­year‐­old man with ischemic cardiomyopathy presented with frequent implantable cardioverter defibrillator (ICD) shocks. Frequent ICD shocks were caused by VT. He had a history of myocardial infarction. This VT was refractory to antiarrhythmic drugs (AADs) and suppressed by sedation with propofol. An emergency VT ablation was performed. Clinical VT cycle length (CL) was 430 ms. Left ventricular endocardial voltage mapping was performed during right ventricular pacing. Pace‐­mapping at the right coronary cusp (RCC) was similar to clinically documented VT. Then clinical VT was induced by programmed stimulation. At the RCC, entrainment mapping showed concealed entrainment and electrogram‐­QRS intervals (23 ms) matched stimulus‐­QRS intervals (29 ms). These findings suggested that the ventricular myocardium captured by RCC was the exit site of this reentrant circuit. RFCA was applied for RCC and left ventricle on opposite side of RCC. We finished this session without confirmation of the inducibility of VT because he developed cardiogenic shock and required IABP support. Two days after ablation, electrical VT storm recurred following cessation of sedation. In this case, VT was refractory to multimodality approach including ICD‐­reprogramming, AADs and catheter ablation except sedation. Therefor cardiac sympathetic denervation (CSD) was attempted on him and bilateral CSD (TH2‐­5) through a video‐­assisted thoracoscopic approach was performed. After bilateral CSD, this refractory VT was completely suppressed and has been no recurrence during 1‐­month follow‐­up.

Conclusion:

This case highlights the effect of bilateral cardiac sympathetic denervation for refractory ventricular tachycardia in patient with ischemic cardiomyopathy.

AP19‐­00497

Utility of ischemic testing prior to ablation for sustained monomorphic VT

Christopher Schumann, Giovanni Davogustto, Andrew Cluckey, Evan Harmon, James Mangrum, Pamela Mason, Rohit Malhotra, Kenneth Bilchick, Andrew Darby, William Stevenson, Nishaki Mehta

University of Virginia, United States

Introduction:

Ischemic testing is frequently performed for patients presenting with sustained monomorphic ventricular tachycardia (SMVT). As SMVT is caused by scar and not active ischemia, the utility of ischemic testing is questionable. Our objective was to determine if ischemic testing prior to SMVT ablation impacts recurrent VT and post‐­ablation mortality.

Methods:

Retrospective analysis was conducted of patients presenting for SMVT ablation at 2 quaternary care centers. VT recurrence and mortality rates were compared between patients who underwent ischemic testing within 30 days of their ablation (ischemic‐­pre) and those who did not (no ischemic) using Kaplan‐­Meier time to event analysis and Cox proportional hazard models.

Result:

164 patients underwent 188 ablations, with ischemic testing performed prior to ablation in 51 patients (31%). Of those 51 patients, 6 (12%) received revascularization prior to ablation. The median duration of follow‐­up was 271 days (IQR 117.5‐­653 days). Rate of VT recurrence did not differ between ischemic‐­pre (42%) and no ischemic groups (57%); log‐­rank P = .120. Mortality was similar in both groups, with 15/113 (13%) deaths in ischemic‐­pre vs 3/51 (6%) deaths in no ischemic group; log rank P = .196. Neither recurrent VT or mortality was found on univariate Cox regression analysis to be predicted by pre‐­ablation revascularization or ischemic testing (HR 0.69, CI 0.43‐­1.11, P = .12 for VT free‐­survival; HR 0.45, CI 0.13‐­1.56, P = .21 for mortality).

Conclusion:

Ischemic testing was found to have no significant effect on recurrent VT and post‐­ablation mortality.

AP19‐­00535

Interesting presentation of a Broad complex tachycardia during the head up tilt table test

Khan Muhammad Taha, Abdul Baqi, Leghari Abid, Khan Aamir Hameed, Yawer Saeed

The Aga Khan University, Pakistan

Introduction:

Broad complex tachycardia (BCT) during head up tilt test (HUTT) is uncommon. Only one study reported incidence of BCT to be around 0.04%. However, patients with ischemic heart disease (IHD) can have ventricular tachycardia/fibrillation during HUTT with isoproterenol augmentation. We describe a case of BCT induced during HUTT without isoproterenol in a patient being evaluated for pre‐­syncope.

Methods:

A 45 years old man with prior history of IHD and percutaneous intervention to LAD coronary artery 10 years ago presented with symptoms of pre‐­syncope. His recent echocardiogram showed left ventricular ejection fraction of 45%‐­50%, no diastolic dysfunction or significant valvular abnormality. His echo and HUTT were done because of pre‐­syncopal symptoms as pre‐­operative evaluation for anal fistula surgery. During HUTT his ECG showed short RP tachycardia at rate of 139 beats/minute with broad QRS complexes but no change of axis. (Figure 1A) His investigations and his ECG traces during HUTT were reviewed and an Electrophysiological (EP) study was scheduled to discern type and origin of BCT as the differential were ventricular tachycardia (VT) and Antidromic atrioventricular reentry tachycardia (AVRT). EP study was performed with fluoroscopy guidance. During EP study ventricular pacing was decremental with central coronary sinus activation while atrial pacing showed no pre‐­excitation. Post‐­dobutamine augmentation, BCT was induced with leftward axis and transition between V1–V2 at a ventricular rate of 140beat/min. During BCT patient remained hemodynamically stable. BCT was confirmed as VT with AV dissociation with faster atrial pacing. Ventricular entrainment showed post pacing interval of 45 msec from mid ventricular septum and 110 msec from right ventricular apex. So it was concluded that VT focus was likely from mid‐­interventricular septum. Patient was counseled regarding VT and ICD therapy however patient refused ICD implantation. As ablation would have been close to His bundle and patient was also due for anal fistula surgery soon patient was kept on amiodarone. Post anal fistula surgery patient had persistent symptoms of pre‐­syncope. VT ablation was then planned however the 3D mapping identified the VT focus about 10 mm away from the His bundle on the LV side.

Result:

Parahisian VTs accounts for up to 10% of all idiopathic VTs and are defined by origin with in 10 mm of His cloud or those with earliest recorded activation in presence of a His potential after mapping of all nearby structures. Such VTs are difficult to ablate as there is high risk for AV block. VT ablation in such cases requires a systematic approach with expertise along with 3D mapping.

Conclusion:

This case highlights unusual occurrence of VT of parahisian origin during HUTT. The use of EP study to reliably diagnose the arrhythmia as VT and use of 3D mapping to identify parahisian region as the VT focus.

AP19‐­00541

Outcome of VT ablation in patients on left ventricular assist device (LVAD) – A descriptive study

Nee Hooi Tan, Khine Sein, Hernandez Jemelee, Paul Chun Yih Lim, Kelvin Chi Ming Chua, Eric Tien Siang Lim, Kah Leng Ho, Boon Yew Tan, Daniel Thuan Tee Chong, Wee Siong Teo, Chi Keong Ching

National Heart Centre Singapore, Singapore

Introduction:

Ventricular arrhythmias (VAs) in patient post‐­LVAD implantation are associated with considerable morbidity from recurrent implantable cardioverter‐­defibrillator (ICD) shocks, progressive heart failure and increased mortality risk.

Methods:

We recruited 2 patients with continuous flow HeartMate II LVADs who underwent radiofrequency catheter ablation (RFCA) in 2018 for incessant, medically refractory VT requiring multiple ICD therapies. We aim to describe the electrophysiological (EP) findings & procedure details.

Result:

Mean age was 70.5 ± 0.7 years old (1 male). The etiology of heart failure was ischaemic cardiomyopathy in 50% of patients (n = 1). Mean LVEF was 23 ± 11%. LVAD were implanted as destination therapy in both patients who were deemed unsuitable for cardiac transplantation. Mean time from LVAD implantation to the development of VT was 42.5 ± 17.7 months. VT was induced in the EP lab with programmed extrastimulation (PES) at the right ventricular apex of up to 3 extrastimuli with a mean of 1.5 ± 0.7 VT morphologies induced. Activation mapping & substrate mapping was performed. Mean VT cycle length (CL) was 434 ± 61 ms. 50 % of patients (n = 1) is scar‐­related re‐­entry VT (RFCA done at the basal to mid/distal anteroseptal and mid/distal anterior LV segments) and 50% of patients (n = 1) is cannula‐­related VT (RFCA done at left posteroapical septal region between the left posterior fascicular exit site & the LVAD cannula inflow). Catheter access to the left ventricle was performed via a transseptal puncture in both patients. Mean procedure time was 295 ± 7.07 minutes & mean fluoroscopy screening time was 59.89 ± 7.87 minutes. Mean RFCA time was 2368 ± 1062 seconds. The VT was successfully treated with RFCA & non‐­inducibility of clinical VT was achieved in both patients with no procedural related complications & death. At 6 months follow‐­up, there was no recurrence of VT observed.

Conclusion:

In this single centre study, RFCA is a viable option & can be safely performed in patients with LVAD presented with incessant, medically refractory VT. However, longer‐­term follow up is required & more data is also required to identify predictors of VT recurrence.

AP19‐­00566

Shotgun workup: A case of ventricular tachycardia from a shotgun pellet 20 years prior

Jennifer Kinaga, Dustin Hill, Roland Filart, Mark Steiner

Orlando Health, United States

Introduction:

Ventricular tachycardia (VT) involving an extracardiac foreign body is extremely rare and there is limited data regarding treatment.

Methods:

N/A

Result:

A 59‐­year‐­old male with history of hypertension and two liver transplants on tacrolimus presented to the hospital with lightheadedness associated with palpitations and shortness of breath. He denied any chest pain or loss of consciousness. Telemetry and initial ECG (Figure A) showed frequent episodes of nonsustained VT (NSVT) 5‐­6 beats, bigeminy, and premature ventricular contractions (PVCs). He had an acute kidney injury and hyperkalemia with an initial potassium of 6.5 mmol/L. Amiodarone was avoided due to his history of liver transplant and ongoing tacrolimus treatment. He was given IV and oral metoprolol with no major response. Despite improvement in potassium and renal function, the ectopy continued. An echocardiogram showed a low normal ejection fraction of 50%‐­54% with no other significant findings. Due to recurrent NSVT a left heart catheterization was performed showing nonobstructive coronary artery disease and a shotgun pellet in the basal right ventricular area (Figure B), also seen on CXR (Figure C). Upon further questioning the patient reported being shot 20 years prior in a hunting accident. An EP study was performed (Figure D‐­F) showing no inducible sustained VT. Unipolar mapping showed a QS pattern in the area just superior to the shotgun pellet, and intracardiac electrograms demonstrated diastolic potentials 31 ms before surface PVC. It was concluded that the origin of the ectopy was 2 mm superior to the shotgun bullet, likely from scar tissue surrounding the pellet. Cardiovascular surgery recommended no surgical extraction given the high complication risk. After a long discussion with the patient regarding cryoablation of the ectopic focus vs a more conservative approach with medical therapy, the patient opted for medical therapy. With increased metoprolol and verapamil his ectopy and symptoms improved. A repeat echocardiogram showed that with the improvement in ectopy his ejection fraction increased to 60‐­64.

Conclusion:

There is minimal data regarding VT originating from scar tissue surrounding a cardiac bullet fragment. Cardiac foreign bodies can cause many complications including acute problems often surrounding the penetrating injury, embolism, arrhythmia, and infection. In regards to treatment, we initially followed what one case series suggested for symptomatic intracardiac foreign bodies and consulted surgery. The benefits of surgery, however, did not outweigh the possible harm in our patient who had not yet gone through less invasive alternatives and whose ectopic focus was caused by tissue surrounding an extracardiac bullet. There was also minimal data on ablating an ectopic focus caused by a foreign body. In this specific case the patient was successfully treated with medical therapy.

AP19‐­00590

The effect of variable bipolar configurations, ablation time and contact force conditions during radio‐­frequency ablation on myocardia

Qinyun Guo, Chenxi Wang, Qi Chen

the Second Affiliated Hospital of Nanchang University, China

Introduction:

Some studies have demonstrated that bipolar radiofrequency ablation (bRFA) can potentially create deeper and larger lesions. However, there remains a little of data regarding optimal catheter orientation and contact forces for bRFA. So we sought to evaluate the efficiency and safety of variable bipolar configurations and different contact forces during bRFA.

Methods:

Swine hearts were excised within 1 hour of experimentation .The catheter tips were oriented in various combinations perpendicular or parallel to the myocardium. During bRFA, the contact force varied from (10‐­30) ± 3 g, ablations were performed at 20‐­60 W for 60‐­120 seconds.

Result:

(1) When bRFA were performed at 25 W for 90 s, with perpendicular configurations catheters, the ablation lesion volumes of 10 ± 3, 20 ± 3, 30 ± 3 g were 382.3 ± 14.9, 482.9 ± 16.9, 512.3 ± 19.3 μL, respectively the ablation lesion depths of 10 ± 3, 20 ± 3, 30 ± 3 g were 12.6 ± 0.3, 13.6 ± 0.2, 14.2 ± 0.3 mm, respectively. There was no significant difference in the POP rate between the three groups (P = .53). 30 ± 3 g group achieved the highest transmurality, No transmurality was achieved in the 10 ± 3 g group. (2) When bRFA were performed at 25 W with the contact force of 10 ± 3 g, with perpendicular configurations catheters, the ablation lesions of 60, 90, 120 s were 337.5 ± 19.9, 382.3 ± 14.9, 382.8 ± 17.4 μL, and the lesion depths were 11.8 ± 1.2, 12.6 ± 0.3, 12.8 ± 0.4 mm. There were no significant difference in lesion volumes and depths between 120 and 90 seconds group, and no significant difference in POP rate of three groups. Three groups all did not achieve transmurality. (3) When bRFA were performed for 60 s, with the contact force of 10 ± 3 g, with perpendicular configurations catheters, the ablation lesions volumes of 20, 25, 50, 60 W were 219.7 ± 18.4, 337.5 ± 19.9, 366.7 ± 19.7, 366.5 ± 24.0 μL; and the lesions depths were 7.5 ± 0.6, 11.8 ± 1.2, 13.3 ± 0.8, 13.1 ± 0.8 mm. There was no significant difference of lesions volumes, depths between the 50 W group and the 60 W group. The POP rate and the transmurality rate were the highest in the 60 W group. (4) When bRFA were performed at 25 W for 90s, with the contact force of 20 ± 3 g, the ablation lesions volumes of perpendicular to‐­perpendicular group, parallel to parallel group, perpendicular to parallel group were 482.9 ± 16.9, 447.7 ± 25.7, 470.0 ± 25.4 μL; and the ablation lesions depths were 13.6 ± 0.2, 10.9 ± 0.5, 12.4 ± 0.3 mm. There was no significant difference in POP rate and transmurality rate between groups.

Conclusion:

In the scope of the 30 ± 3 g, with the increase of contact force, the ablation lesions volumes, depths, transmurality rate of bipolar radiofrequency ablation increase .But the POP rate did not obviously change when the contact force changed. In the scope of ablation time of 90 seconds, with the extension of time, the ablation lesions volumes, depths of bipolar radiofrequency ablation increased significantly. Ablation power have a significant impact on bipolar radiofrequency ablation lesions volumes, depths, with the increase of power, the depths and volumes of ablation lesions increased, as well as the POP rate and transmurality rate. The largest lesions volumes, depths were achieved with both catheter tips oriented perpendicular to the myocardium, and the smallest with both catheter tips oriented parallel to the myocardium .There was no significant correlation between the POP rate and the catheter tips orientation.

AP19‐­00592

Verapamil‐­sensitived ventricular tachycardia originating from anterior papillary muscle

Tetsruro Takase, Masaharu Maegaki, Kazunori Takemura, Naoki Nozaki

Ayase Heart Hospital, Japan

Introduction:

Verapamil‐­sensitive VT generally presents with RBBB + left axis deviation and originates from posterior fascicle of left bundle branch. Purkinje potential is usually observed at the successful point of ablation. Verapamil‐­sensitive VT with RBBB + right axis deviation is relatively uncommon and is thought to be originated from anterior fascicle. Here we reported a case of VT with this pattern.

Methods:

The patient is 66‐­year‐­old male. He presented to ER with dizziness. ECG showed tachycardia with wide‐­QRS complex at 180 bpm. Verapamil was administered intravenously and promptly convert it to sinus rhythm. During observational admission, he repeatedly had sustained VT episodes several time and was referred for ablation. Echocardiogram showed moderate mitral regurgitation, mildly dilated left atrium, preserved LV function (EF = 57%) with no asynergy. 12‐­lead ECG showed wide QRS complex with AV dissociation, RBBB, inferior axis and right axis deviation, suggesting VT originating from lateral part of the base of LV. Clinical VT was readily induced during the procedure. We used Rhythmia 3D‐­mapping system and intracardiac echo to localize the origin. Orion catheter was introduced to LV through transseptal puncture sheath. Activation mapping and pace mapping located the origin to be at the tip of anterior papillary muscle, close to A1 (lateral part of anterior leaflet of mitral valve).

Result:

Ablation was applied supravalvularly but failed to terminate VT. Alternatively infravalvular approach by making a U‐­shape of ablation catheter had a good contact with the target site and successfully rendered VT non‐­inducible.

Conclusion:

Intracardiac echo is a useful tool to correlate 3D mapping with anatomical structure in cases of verapamil‐­sensitive VT.

FIGURE 1 12‐­lead ECG of VT. R 180 bpm inferior axis RBBB+RAD

FIGURE 2 Intracardiac echo‐­guided ablation showing tip of the catheter at anterior papillary muscle

AP19‐­00601

Substrate modification of ventricular tachyarrhythmias in acromegalic cardiomyopathy

Sung‐Hao Huang, Fa‐Po Chung, Yenn‐Jiang Lin, Shih‐Lin Chang, Li‐Wei Lo, Yu‐Feng Hu, Ting‐Yung Chang, Chin‐Yu Lin, Da‐Chuan Duan, Tze‐Fan Chao, Jo‐Nan Liao, Shih‐Ann Chen

National Yang‐­Ming University Hospital, Taiwan

Introduction:

Acromegaly may present a variety of cardiac arrhythmia with disease progression. Complex ventricular ectopy is common in acromegaly patient; however, sustained ventricular tachycardia (VT) is rare. Late diagnosis of acromegaly may lead to amyloidotic cardiomyopathy (CM) and sequential lethal ventricular arrhythmia (VA) without fully reversible even after pituitary surgery. We report a patient undergoing ablation of drug refractory VT originating from perimitral epicardium in acromegalic CM.

Methods:

‐­

Result:

A 67‐­years‐­old man presented typical acromegaly appearance received previously successful pituitary gland surgery. He visited for medical help due to monomorphic VT occurred in April 2015. Echocardiography showed concentric left ventricular (LV) hypertrophy, right ventricular thickening, normal LV systolic function and dilated atria; the hallmark of acromegalic CM. The patient experienced multiple VT episodes in the following 2 years treatment period (Figure A) although all episodes could be terminated by implantable cardioverter defibrillator (ICD) anti‐­tachycardia pacing (ATP) therapies (Figure B). Due to the patient presented increasing VT burden, he underwent electrophysiological (EP) study. Programmed stimulation during EP study induced ventricular fibrillation (VF) and multiple monomorphic VT. The electroanatomic substrate mapping was created by Ensite PrecisionTM, (St Jude Medical) using a duodecapolar catheter. Biventricular endocardium demonstrated normal bipolar voltage mapping, while unipolar voltage mapping delineated potential abnormal substrates surrounding basal posterior perimitral areas. Epicardial substrate modification by eliminating the fragmented and delayed potentials rendered the VT/VF non‐­inducible (Figure C). During 12 months followed‐­up period, the patient has free of VA recurrence.

Conclusion:

Detailing cardiovascular (CV) system assessment in acromegaly patients is recommended to prevent and early detect acromegalic CM. Acromegalic CM may not be fully reverse even after treatment and the arrhythmia issues should be focused. The present case highlighted that late‐­onset VT/VF may occur in acromegalic CM and substrate‐­based ablation strategy can effectively prevent VA recurrence.

AP19‐­00625

A case of arrhythmogenic right ventricular cardiomyopathy presenting the electrocardiographic characteristics with Brugada syndrome

Yosuke Murase, Hajime Imai, Katsuhiro Kawaguchi, Yasuhiro Ogawa, Motoharu Hayashi, Naoaki Kano, Takashi Okajima, Kei Okabe, Kenji Arai, Nariko Tsukamoto, Toyoaki Murohara

Komaki City Hospital, Japan

Introduction:

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is characterized by structural or electrocardiographic abnormalities, such as right ventricular dilatation or epsilon like waves. Recent studies have revealed that some patients with Brugada syndrome (BrS) showed the same clinical features with ARVC. However, the clinical features of patients with an overlapping disease state of ARVC and BrS are unknown.

Methods:

We reported a case of ARVC presenting the electrocardiographic characteristics with BrS.

Result:

A 71 years old man who presented with an out‐­of‐­hospital cardiac arrest due to ventricular tachycardia (VT). After arrival at our hospital, the return of spontaneous circulation was achieved by electrical defibrillation. He had no family history of sudden cardiac death. The electrocardiogram (ECG) showed spontaneous coved‐­type ST segment elevation, complete right bundle branch block and T‐­wave inversions in leads V1, V2, V3 and V4. However, the echocardiography and right ventricular (RV) angiography demonstrated RV dilatation and akinesis in the inferior and free wall of RV. In addition, the morphology of VT was the left bundle branch block (LBBB) and inferior axis. These structural and electrocardiographic abnormalities met with the 2010 revised task force criteria for ARVC. On the other hand, the coved‐­type ST segment elevation was normalized after hospital admission. During hospitalization, the patient had high‐­grade fever due to sepsis. During high‐­grade fever, he had frequent VT episodes and the ECG showed coved‐­type ST segment elevation. When his fever went down, the coved‐­type ST segment elevation was normalized. In electrophysiological study, coved‐­type ST segment elevation was presented after pilsicainide infusion and VT was induced by right ventricular outflow tract stimulation. These electrocardiographic features was consistent with BrS. During the in‐­hospital course, he underwent a endocardial catheter ablation. The low voltage area extended to the inferior and free wall of RV and the anterior and septum of right ventricular outflow tract (RVOT). The clinical VT was induced by program stimulation, but VT was hemodynamically unstable. Therefore we performed pacemap to match the morphology of clinical VT and we ablated from the anterior to the septum of RVOT. The patient was discharged from our hospital after insertion of an implantable cardioverter defibrillator.

Conclusion:

This was a rare case of overlap of ARVC and BrS. We speculated that myocardial degeneration of RVOT due to ARVC led to the electrocardiographic abnormalities which were consistent with BrS. In this case, the patient showed coved‐­type ST segment elevation due to high‐­grade fever and VT was frequently occurred. Therefore, more attentive treatment for high‐­grade fever is required to prevent VT episode.

AP19‐­00641

Treatment of pulmonary sinus cusp‐­derived ventricular arrhythmia with reversed U‐­curve catheter ablation

Yufan Yang, Qiming Liu

The Second Xiangya Hospital, China

Introduction:

The origin of pulmonary sinus cusp (PSC)‐­derived ventricular arrhythmia (VA) is a highly specialized anatomical structure; therefore, insertion of the radiofrequency ablation catheter tip to the target site to ensure safe ablation is a major challenge for clinicians.

Methods:

A retrospective analysis and summary of the clinical data of 15 patients undergoing catheter ablation for PSC‐­derived VA in Cardiac Intervention Therapy Center, The Second Xiangya Hospital of Central South University between January 2013 and July 2015 was conducted.

Result:

For the 15 patients, the PSC‐­derived VA originated from the lower regions of the pulmonary sinuses, leading from the right, left, and anterior sinuses of the PSC in 4, 6, and 5 patients, respectively. Nine patients with PSC‐­derived VAs originating from the right and anterior sinuses underwent successful reversed U‐­curve catheter ablation, while the other six cases with arrhythmias originating from the left sinus underwent successful ablation with the conventional method (nonreversed U‐­curve catheter ablation). All the patients were followed‐­up for 6‐­31 months, and no cases of recurrence or complications occurred.

Conclusion:

Reversed U‐­curve catheter ablation is suitable for VAs originating from the right and anterior PSCs, while conventional ablation can also be used for those originating from the left PSCs.

AP19‐­00645

Predicting ventricular arrhythmia in acute myocardial infarction from surface

Annisa Tridamayanti, Trisulo Wasyanto

Faculty of Medicine, Sebelas Maret University, Indonesia

Introduction:

Acute myocardial infarction is associated with ventricular arrhythmia and cardiac arrest. This study was to determining ECG parameter to predicting ventricular arrhythmia

Methods:

The clinical data of patients who had been diagnosed with ST elevation myocardial infarction and Non‐­ST elevation myocardial infarction from 2017 to 2018 were retrospectively reviewed. All ECG parameter were obtained and analyzed using SPSS 20.0 for univariate, bivariate, multivariate and Receiver Operator Characteristic (ROC) analysis

Result:

A total of 301 patients were included in this study. There were 97 patients occur ventricular arrhythmia during hospitalization. From univariate and bivariate, QT dispersion and TpTe were significantly prolonged among cases vs controls (P ≤ .05). Cut‐­off point was determine using ROC curve for QT dispersion (Cut‐­off >23.5 ms; AUC 0.644; P < .001), QRS duration (Cut‐­off >101.3 ms; AUC 0.667; P < .001) and TpTe (Cut‐­off >122.2 ms; AUC 0.773; P < .01). After multivariate analysis, three covariates were discovered to be significant with scoring 1 for each covariate: QTD > 23.5 ms, QRS duration >101.3 ms, and TpTe > 122.2 ms. The score above 1 indicates high risk for emergence ventricular arrhythmia (AUC: 0.773; P < .05; Sensitivity 60.9%; Specificity 80%).

Conclusion:

ECG Parameter scoring of QTD, QRS duration, and TpTe is reliable, simple clinical prediction rule to indicate risk of ventricular arrhythmia. This CPR might help physician to more attention and prioritize to invasive reperfusion strategy.

AP19‐­00703

Electrophysiological characteristics of idiopathic premature ventricular contraction or ventricular tachycardia arising from right ventricular outflow tract

Haruna Tabuchi, Hidemori Hayashi, Yuki Kimura, Hiroki Matsumoto, Gaku Sekita

Juntendo University, Japan

Introduction:

Ventricular arrhythmias arising from right ventricular outflow tract (RVOT) have different expression as premature ventricular contraction (PVC) or ventricular tachycardia (VT). However, its clinical characteristics are still unclear.

Methods:

The study included consecutive patients who underwent catheter ablation (CA) for idiopathic RVOT‐­PVC/VT in our institution from 2014 to 2019. Eligible patients were divided into two groups in accordance with the presence of VT.

Result:

Overall, 65 patients were examined. There were 47 patients with RVOT‐­PVC (without VT, group 1) and 18 patients with RVOT‐­VT (group 2). There was no significant difference in age, gender, CA success rates, and local activation time preceding the onset of QRS in successful CA site. In electrode I, group 1 showed negative polarity in 41 cases (87.2%), whereas group 2 showed positive polarity in 14 cases (77.8%). RVOT‐­PVC was eliminated by anteroseptal wall ablation in 39 patients (83.0%) in group 1, however RVOT‐­VT was terminated by posteroseptal wall ablation in 15 patients (83.3%) in group 2.

Conclusion:

RVOT‐­PVC has been considered to have a good prognosis, however VT complication rate is significantly high when electrode I polarity is positive, which implies posteroseptal origin.

AP19‐­00704

Characteristics and short‐­term prognosis of patients with ventricular arrhythmias: Data from Tokyo CCU network registry

Akira Ueno, Yoshinori Kobayashi, Shouhei Kataoka, Hiroshige Murata, Seiji Fukamizu, Norikazu Watanabe, Kaoru Tanno, Takeshi Yamamoto, Ken Nagao, Morimasa Takayama

Tokyo CCU Network Scientific Committee, Japan

Introduction:

Patients suffering from ventricular tachycardia (VT) /fibrillation (VF) have poor prognosis despite of intensive treatments and cares. However, their details have been rarely investigated on a large scale.

Methods:

Patients with VT or VF, except apparently acute ischemic cause, were recruited from Tokyo CCU Network Registry database in 2012‐­2016. Their characteristics and short‐­term prognosis were retrospectively evaluated.

Result:

Out of 6304 patients who were hospitalized due to cardiac arrhythmias without acute ischemic cause, a total of 1985 patients (average 65 ± 17 y/o, males 76%) with VT or VF were recognized. They included 596 patients (30.0%) with ischemic heart disease such as old myocardial infarction or ischemic cardiomyopathy, 174 patients (8.8%) with dilated cardiomyopathy (CM), 150 patients (7.6%) with hypertrophic CM, 77 patients (3.9%) with valvular heart disease, 48 patients (2.4%) with cardiac sarcoidosis, 39 patients (2.0%) with arrhythmogenic right ventricular CM and 27 patients (1.4%) with vasospastic angina. Nineteen patients (0.8%) with Brugada syndrome and 16 patients with QT prolongation syndrome (0.8%) were also observed. Total short‐­term (in‐­hospital) mortality was 11.1%, and patients with valvular heart disease and ischemic heart disease had poor prognosis (16.9% and 14.2%, respectively).

Conclusion:

Patients with VT/VF had a high mortality, especially with valvular heart disease and ischemic heart disease. Further studies and establishment of the treatment strategies for such patients are needed.

AP19‐­00707

Focal ventricular tachycardias (VT) in structural heart disease: Prevalence, characteristics and clinical outcomes after catheter ablation

Robert Anderson, Geoffrey Lee, Timothy Campbell, Ivana Trivic, Timmy Pham, Chrishan Nalliah, Eddy Kizana, Stuart Thomas, Siddharth Trivedi, Troy Watts, Jonathan Kalman, Saurabh Kumar

Royal Melbourne Hospital, Australia

Introduction:

Background The most common mechanism of ventricular tachycardia (VT) in patients with structural heart disease (SHD) is scar‐­related re‐­entry. Focal VT is typically seen in patients without SHD and is rarely seen as a dominant mechanism in patients with established or acute ischaemic heart disease (IHD). There is a paucity of data characterising focal VTs remote or adjacent from regions of dense scar in patients with SHD. In this study, we report the frequency, procedural characteristics and subsequent clinical outcomes in a series of patients with SHD shown to have a focal mechanism despite the presence of scar and the typical electrophysiological milieu for re‐­entrant VT. Aim To summarise the procedural characteristics and outcomes of patients with structural heart disease (SHD) who have focal VT.

Methods:

Consecutive patients with SHD undergoing VT ablations over the previous 2‐­year period were included. Patients were included with SHD (ischaemic or non‐­ischaemic) who were referred for catheter ablation for medically refractory VT. In addition to using programmed electrical stimulation (PES) during induction, we included burst RV pacing and an isoprenaline protocol pre‐­ and post ablation.

Result:

Nineteen of 112 patients with SHD (17%) undergoing VT ablation over 2 years had a focal VT mechanism elucidated (mean age, 67 ± 13 years; ejection fraction, 46% ± 14%; non‐­ischemic cardiomyopathy 10). Repetitive failure of termination with anti‐­tachycardia pacing (69% of patients) or defibrillator shocks (56%) was a common feature of focal VTs. A median of 3 VTs/patient were inducible (28 focal, 34 re‐­entrant VTs; 53% of patients with both focal and re‐­entrant VT mechanism). Focal VTs originated from the right ventricle (RV: 68%) than the left ventricle (LV: 32%) (Figure). In the RV, the RV outflow tract was the most common (37% of all focal VTs), RV moderator band (21%), apical septal RV (1 patient; 5%) and lateral tricuspid annulus (1 patient; 5%). The lateral LV (non‐­Purkinje) was the most common LV focal VT site (16%) followed by the papillary muscles (15%). After a median follow‐­up of 276 days, 79% of patients remained arrhythmia‐­free; no patients had recurrence of focal VT at repeat procedure. In those with recurrence, defibrillator therapies were significantly reduced from a median of 53 anti‐­tachycardia pacing (ATP) episodes pre‐­ablation to 10 ATP episodes post ablation. During follow‐­up, 2 patients (11%) underwent repeat VT ablation; none had recurrence of focal VT.

Conclusion:

Focal VTs are common in patients with SHD often coexisting with re‐­entrant forms of VT. High rates of failure of defibrillator therapies was a common feature of focal VT mechanism. Uncovering and abolishment of focal VT may result in further improvement in outcomes of catheter ablation in SHD.

AP19‐­00709

Simultaneous pace during ablation approach to achieve scar non‐­excitability as a substrate‐­based catheter ablation endpoint of ventricular tachycardia

Robert Anderson, Geoffrey Lee, Timothy Campbell, Ivana Trivic, Timmy Pham, Chrishan Nalliah, Eddy Kizana, Stuart Thomas, Siddharth Trivedi, Troy Watts, Jonathan Kalman, Saurabh Kumar

Royal Melbourne Hospital, Australia

Introduction:

A simultaneous pace‐­ablate strategy to achieve electrical non‐­excitability has not previously been evaluated in the VT ablation cohort. In this study, we outline an additional ablation endpoint for targeting scar‐­related VT substrate.

Objectives:

To summarise the procedural characteristics and outcomes of patients with structural heart disease (SHD) undertaking a substrate‐­based catheter ablation of ventricular tachycardia (VT) until high‐­output pacing loss‐­of‐­capture with simultaneous ablation.

Methods:

Substrate‐­based catheter ablation was performed where loss of pacing capture was used as the ablation lesion endpoint using bipolar pacing at a fixed output of 600 ms with 10 mA and a 9 ms pulse width.

Result:

Twenty‐­three VTs were inducible in 7 patients with a total of 868 ablation lesions applied using simultaneous bipolar pacing with the acute ablation endpoint of tissue loss‐­of‐­capture. The mean age was 72 ± 3 years (all men, mean LV ejection fraction of 29% ± 7%; ischaemic cardiomyopathy, 6; recurrent ICD shocks and electrical VT storm, 5) with a median endocardial bipolar scar of 64.8 cm² (IQR25‐­75 52.1‐­136.3 cm²), equating to 47% (IQR 25‐­75 42%‐­56%) of the total ventricular surface. The median ablation area was 22.2 cm² (IQR 25‐­75 16.3‐­68.1 cm²) which converted to a median percentage of bipolar scar ablated to be 41% (IQR 25‐­75 27%‐­66%). Overall, the median ablation lesions per patient was 101 lesions (IQR 25‐­75 80‐­173) and the total ablation time was 51 minutes (IQR 25‐­75 41‐­72 minutes) with average duration per lesion of 30.3 seconds (IQR 25‐­75 23.7‐­38.3 seconds). Median total energy was 115,798 joules (IQR 25‐­75 92 081‐­158 163 J) and average power was 33.2 Watts (IQR 25‐­75 32.2‐­36.3 W). Median impedance drop was 9.7 ohms per lesion (IQR 25‐­75 9.1‐­9.9 ohms) and CF was 11.9 g (IQR 25‐­75 10.2‐­12.7 g). There was no VF episodes during any pacing and simultaneous ablation session. The median procedure time was 270 minutes (IQR 25‐­75 218‐­370 minutes). Acute procedural success was seen in 6 patients (86%) and partial success in the remaining patient. After a median follow‐­up of 246 days, there was no VT recurrence or repeat ablation procedures in any patient. One patient died within 30 days following re‐­admission with multi‐­organ dysfunction without recurrent ventricular arrhythmias. In addition, 4 patients (57%) had a reduction in AAD therapy.

Conclusion:

Achieving scar non‐­excitability as an additional endpoint to complete scar homogenisation during catheter ablation of scar‐­VT is an effective technique to suppress recurrent VT and reduce AAD therapy in a high‐­risk group of patients with recurrent ICD shocks, severe cardiomyopathy and extensive scar substrate. In conjunction with high‐­density mapping and guidance with real‐­time ICE feedback, it appears safe and does not increase procedural or ablation time.

FIGURE 1 A 74‐­year‐­old with ischaemic cardiomyopathy (LVEF = 37%) presented with electrical VT storm with a clinical VT demonstrating a RBBB (transition in V4)/superior axis morphology. 5 VT morphologies were induced during mapping and catheter ablation (VT1‐­5, Panel A) with VT3 matching the clinical VT (Panel B). EAM showed extensive basal inferior and antero‐­lateral low voltage (Panels C and D). Substrate‐­based ablation was performed to abnormal late potentials with this scar utilising simultaneous high‐­output pacing (10 mA at 9 ms pulse width) to achieve scar non‐­excitability. Impedance recordings during pace and ablation demonstrate ˜10ohm reduction at 40W power (without any pacing interference, Panel E). Examples of ablation with initia pace‐­capture to loss‐­of‐­capture were demonstrated, including pacing delay prior to loss‐­of‐­capture (Panel F). Both high‐­density mapping and ablation sites were guided by real‐­time ICE, which could also indicate underlying lesion formation during ablation (Panel G).

AP19‐­00710

Suppression of polymorphic ventricular tachycardia by endocardial ablation targeting delayed potential in cardiomyopathy of unknown etiology with QT prolongation

Yuta Sudo, Hiroyuki Okada, Emiko Nakashima, Hiroshi Inagaki

Soka Municipal Hospital, Japan

Introduction:

Although several strategies were advocated in catheter ablation of stable monomorphic ventricular tachycardia (VT), therapeutic strategies have not been established in polymorphic VT.

Methods:

A 49 year‐­old man who had no history of cardiac events was admitted to our hospital due to acute decompensated heart failure. The electrocardiogram (ECG) showed atrial fibrillation with QT interval prolongation. The echocardiogram revealed a poor left ventricle function with diffuse hypokinesis. Coronary angiography and endocardial biopsy revealed no apparent etiology of heart failure. About 3 weeks after admission, radiofrequency (RF) ablation was performed due to frequent episodes of polymorphic VT despite using various types of anti‐­arrhythmic drugs under deep sedation. Endocardial electroanatomical mapping of the left ventricular (LV) endocardium during sinus rhythm constructed by using multi‐­electrode mapping catheter (HD Grid®︎) revealed no presence of a low voltage area. Delayed potential (DP) could be recorded in the LV posterior wall in accordance with the terminal portion of the T wave of the 12 lead ECG. RF ablation was performed at the area. The amplitude of the delayed potential decreased with each delivery of RF energy, and QT interval shortened after RF ablation. At the end of the session, polymorphic VT was not inducible.

Result:

Up to now, polymorphic VT has not been recurred with the treatment of bisoprolol 1.25 mg daily.

Conclusion:

RF ablation guided by DP might be effective for treatment of polymorphic VT in patients without ventricular scar.

AP19‐­00720

Absolute alcohol ablation in coronary veins

Mark TK Tam, Joseph YS Chan

Chinese University of Hong Kong, Hong Kong

Introduction:

Ventricular arrhythmia originating from left ventricular summit are difficult to be treated with traditional endocardial or epicardial catheter ablation. We describe a of case of ablation with absolute alcohol injected into coronary veins with good effect.

Methods:

Case report

Result:

A 53 years old male with history of non‐­ischemic dilated cardiomyopathy was noted to have monomorphic PVC possibly contributing to his poor ejection fraction of 18%. He agreed for electrophysiological study and ablation for his PVC. Electrophysiological study was performed with Carto electro‐­anatomical mapping system. Spontaneous monomorphic PVC with an inferior axis, transition at V3 and slurred upstroke, QS complex in lead I was recorded. The morphology suggests possible exit from left ventricular summit. Pace mapping with ablation catheter in RVOT and aortic cusps both did not match with the PVC morphology. Mapping at distal great cardiac vein showed good but not perfect pace map, local signal around 30 msec preceding PVC. Ablation with irrigation ablation catheter at this site fail to suppress the PVC. Detailed mapping with coronary wire shielded with a microcatheter (finecross catheter) showed excellent pacing mapping at a branch of coronary vein, with local unipolar signal preceding PVC by 40 msec suggesting a promising site for ablation. However, ablation catheter, with its large caliber, cannot reach this small venous branch. Decision was made for ablation with absolute alcohol. With a monorail 2.0 mm balloon to occlude the vein to prevent spill over, 2.5 mL of absolute alcohol was slowly injected into this venous branch. Slow run of idioventricular rhythm was resulted. After that PVCs were non‐­inducible. Post procedure echocardiogram confirmed absence of pericardial effusion.

Conclusion:

Ablation with absolute alcohol in coronary veins is potential alternative approach for ventricular arrhythmia if endocardial approach fails.

AP19‐­00737

The clinical and electrophysiological characteristics of nonsustained repetitive monomorphic ventricular tachycardia from the left his‐­purkinje system

Cheng Wang, Minglong Chen

The First Affiliated Hospital of Nanjing Medical University, China

Introduction:

Repetitive monomorphic ventricular tachycardia (RMVT) arising from the left His‐­ Purkinje system can occasionally encountered during clinical practice. We describe 7 such cases as a unique entity in this study to characterize their clinical and electrophysiological features.

Methods:

Seven patients with frequent palpitation (5 men with median age of 23 years; IQR, 12˜50) were included in the study from January, 2003 to July, 2018. 12‐­lead ECG, Holter and Echocardiographic tests were performed after medical history interrogations and physical examinations. Antiarrhythmic drug therapy was essential to all patients and catheter ablation would be attempted if the patients could not tolerate or were not response to the drug therapy.

Result:

No patients had the history of syncope and the family history of sudden cardiac death. ECG recording was characterized by frequent ventricular extrasystoles, ventricular couplets, and salvos of non‐­sustained VT competitive with sinus rhythm. The QRS morphology of ectopic beats was in the right bundle branch block pattern with severe left axis deviation. The width of QRS complex was 135 ms (120˜140) during ventricular tachycardia. Verapamil had no effect on VT except for one case with partial effectiveness. The enlargement of the left ventricle was found in 2 patients. Three out of 5 were successful with catheter ablation treatment.

Conclusion:

RMVT arising from the left His‐­Purkinje system is a special arrhythmic entity and non‐­verapamil sensitive. Its electrophysiological mechanism looks to be focal firing and the electro‐­ pharmacological study is further needed. Catheter ablation can be a treatment option in symptomatic and high burden patients.

TABLE 1 Baseline characteristics of patients with RMVT

Patient no.	Sex	Years	Couple intervals	VT‐ CL (ms)	VT‐ QRSd (ms)	LVDD (mm)	LVEF (%)	Follow‐ up (month)
1	Male	50	250	Varity	135	48	69	167
2	Male	23	355	350	135	43	67.5	130
3	Male	22	370	320	140	47	62.9	133
4	Male	12	440	420	120	56	48.9	110
5	Female	15	360	340	139	53	45.2	6
6	Male	40	400	300	130	49	65.0	18
7	Female	33	440	360	130	51	64.5	9

Abbreviations: RMVT, Repetitive monomorphic ventricular tachycardia; VT, ventricular tachycardia; CL, cycle length; LVDD, left ventricular end diastolic dimension; LVEF, left ventricular ejection fraction.

TABLE 2 Electrophysiological characteristics of RMVT and the successful ablation site

Patient no.	Induction mode	Entrainment	Mappable arrythmia	PP‐ QRS,ms	Sinus HV, ms	Complex potential (FPP)	Success	RFCA area
1	Spontaneous	—	PVC	25	45	No	Yes	Mid‐LPF
4	Spontaneous	—	PVC	13	42	No	No	Mid‐LPF
5	Spontaneous	—	PVC	35	55	No	No	left His bundle
6	Spontaneous	—	PVC	15	35	Yes	Yes	Mid‐LPF
7	None‐sustained	—	Pacing	*n/a	44	Yes	Yes	Mid‐LPF

Abbreviations: HV, His‐ventricle; RMVT, non‐reentrant fascicular tachycardia; PP, presystolic Purkinje potential; PVC, premature ventricular complex; VP, ventricular pacing; and VT, ventricular tachycardia; LPF, left posterior fascicle. —, not be entrained; *n/a =not available HV interval could not be recorded of VT because VT was terminated Spontaneously at beginning). FPP: fragmented antegrade Purkinje potential.

FIGURE 1 Twelve‐­lead ECG of Repetitive monomorphic ventricular tachycardia at baseline in 7 subjects. The QRS wave of ectopic heart rhythm is shown as a right bundle branch block obvious Left axis deviation, and the median (IQR) QRS width was 135ms (120–140) in lead V1

FIGURE 2 Endocardial recordings of patient 6 during sinus rhythm and frequent PVC. FPP was shown by black arrow, preceding the onset of the surface QRS pattern by 15ms at the left inferior aspect of the ventricular septum

AP19‐­00749

Catheter ablation of parahisian premature ventricular contraction: the value of ablation underneath the septal leaflet of tricuspid valve

Xinhua Wang, Zheng Li, Lingcong Kong, Minhua Zang, Jun Pu

Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan 430060, PR China, China

Introduction:

Objective The efficacy of parahisian premature ventricular contraction (PVC) ablation is compromised due to the high risk of atrioventricular (AV) conduction injury. Compared with the conventional direct proximity technique, the catheter inversion technique may improve the efficacy of ablation.

Methods:

Thirty symptomatic patients with parahisian PVC (17 males; average age 51.4 ± 7.9 years) were enrolled from Jan 2017 to Nov 2018. There were 11 patients with hypertension, 5 with type 2 diabetes mellitus and 2 with coronary artery disease and PCI therapy. The average number of PVC per day was 14375 ± 648. Surface ECG showed the morphology of QRS was R, Rs, rS or RS pattern in the inferior leads (II/III/aVF), R pattern in lead I and aVL, and QS (n = 29) or QR pattern (n = 1) in lead V1. The precordial transitional lead was in V2 / V3. According to the time of enrollment, the patients were divided into two groups: direct proximity (Group 1, n = 14) and catheter inversion (Group 2, n = 16). In Group 1, the catheter was advanced directly and reached the right‐­sided parahisian area. In Group 2, the catheter was curved underneath the septal leaflet of tricuspid valve and back toward the annulus. Three‐­dimensional activation and pacing mapping was carried out to localize the origin of PVC. The most preceding local activation with the coincidence of paced QRS with clinical PVC in at least 11‐­12 leads was targeted for ablation. For each lesion, saline irrigated radiofrequency (RF) energy was delivered at 25‐­40 W and lasted for 60 s. The procedural success was defined as disappearance of PVC at the end of 30 minutes’ observation by isoproterenol (2‐­5 μg/min) challenge. Clinical success was defined as no recurrence of homomorphic PVC 2 months after the procedure. The reduction of 24‐­hour PVC burden by more than 80% was deemed effective.

Result:

There was no significant difference in PVC burden and other baseline characteristics between the two groups prior to ablation. In Group 1, the ablation target was located within 5 mm above His bundle in 2 cases and within 5 mm below His in 12 cases. The average time preceding the onset of the QRS was 25.2 ± 4.3 ms, and the average RF delivery times were 3.5 ± 1.2. Procedural success was achieved in 8 patients, while clinical success was achieved in 5 (35.7%). In the remaining 3 patients, the PVC burden decreased by more than 80%. In Group 2, and the ablation target was located within 2 mm above His bundle in 1 case and within 4 mm below His bundle in 15 cases. The average time preceding the onset of the QRS was 26.3 ± 5.1 ms. The average RF ablation times were 2.5 ± 1.4. Procedural success was achieved in 14 cases, and clinical success was achieved in 12 cases (75%). In 1 case, PVC burden decreased by more than 80%. The clinical success rate was higher in Group 2 than that in Group 1 (P < .03). Transient 2:1AV block developed in 1 case during ablation in Group 1, and resolved by immediate suspension of RF delivery.

Conclusion:

RF ablation for parahisian PVC by catheter inversion technique yielded better clinical results than by conventional direct proximity technique, which can be considered as the first‐­line choice.

AP19‐­00760

Ventricular tachycardia arising from aortomitral continuity : the similarity of electrocardiographic characteristic of left ventricle outflow tract tachycardia

Haikal Haikal

Binawaluya Cardiac Center, Indonesia

Introduction:

The ECG of left ventricular outflow tract (LVOT) arrhythmias ventricular can mimic each other because of their anatomical vicinity.

Methods:

A 55 year‐­old man came with a chief complain of palpitation. ECG showed sinus rhythm and frequent premature ventricular contraction (PVC) with inferior axis, qR pattern in lead V1 with no transition zone and absence of S wave in lead V5 or V6. Holter monitoring showed non sustained VT. EP study was performed with 3‐­D mapping and showed the origin of PVC near left coronary cusp of the aorta. Radio frequency ablation was performed and terminate the PVC. Holter monitoring post procedure showed no significant reduction of PVC burden with the same morphology. Second attempt for the RF ablation was performed and showed that the origin of PVC its on the aortomitral continuity (AMC). Holter monitoring post procedure evaluation showed significant reduction of PVC burden

Result:

Patients with LVOT VT display common electrocardiographic features, probably due to the close proximity of those locations. Mapping at AMC should be considered before an attempt of ablation in the aortic cusp.

Conclusion:

Patients with LVOT VT display common electrocardiographic features, probably due to the close proximity of those locations. Mapping at AMC sholud be considered before an attempt of ablation in the aortic cusp.

AP19‐­00761

Pulmonary artery denervation reduces ventricular tachycardias

Zhibing Lu, Xiaoying Wang, Da Luo, Weiyi Qu, Chao Chen, Xiaomei Yu, Wenbo He, Jing Xie, Hong Jiang

Zhongnan Hospital of Wuhan University, China

Introduction:

Electrical stimulation of the left stellate ganglion (LSG) can elicit ventricular arrhythmias (VAs) originating from the right ventricular outflow tract (RVOT). Previous studies indicated that nerve from the LSG and middle cervical ganglion pass through the pulmonary artery before reaching the right ventricle. The purpose of this study is to investigate the effects of selective pulmonary artery denervation (PADN) on blood pressure (BP), sympathetic activity, ventricular effective refractory period (ERP) and incidence of VAs induced by LSG stimulation.

Methods:

In Protocol 1, heart rate variability (HRV) and serum norepinephrine (NE) were compared before and after PADN. Changes of BP and ventricular ERP induced by stimulating LSG before and after PADN in 11 canines were observed. In Protocol 2, His bundle was ablated to construct complete atrioventricular block in 8 anesthetized canines. PADN was performed by radiofrequency energy and confirmed by high‐­frequency stimulation. Incidence of VAs induced by LSG stimulation were compared before and after PADN. Immunostaining examinations for pulmonary artery were performed in another two canines.

Result:

In Protocol 1, the low‐­frequency component of HRV and serum NE were significantly reduced by PADN. Changes of BP induced by LSG stimulation were not significant after PADN. Changes in ventricular ERP induced by LSG stimulation were significantly attenuated by PADN only on the sites of RVOT. In Protocol 2, the numbers of PVC, episodes, and duration of sustained VT induced by LSG stimulation were significantly reduced after PADN. Abundant sympathetic nerve bundles were observed in pulmonary artery especially in the anterior epicardium.

Conclusion:

PADN could attenuate the cardiac sympathetic activity, prolong the ventricular ERP and reduce the prevalence and duration of VT induced by LSG stimulation, more selectively on the sites of RVOT.

AP19‐­00767

A rare complication of paroxysmal ventricular tachycardia following interventional closure of ventricular septal defect and the treatment with radiofrequency catheter ablation

Ruizheng Shi, Yanbo Liu, Qian Xu

Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, China

Introduction:

Trans‐­catheter closure of peri‐­membranous ventricular septal defects using Amplatzer‐­ Type devices, has been widely reported in the past decade. It has been proven to have high closure rates, low mortality as well as low rate of complications. We hereby report a rare complication of frequent premature ventricular contractions (PVCs) and paroxysmal ventricular tachycardia sustained 48 days after the closure of VSD in an 8 year‐­old patient. More importantly, the arrhythmias were successfully treated with radiofrequency catheter ablation (RFCA) after medical therapy failed to restore and maintain sinus rhythm.

Methods:

The 8‐­year old boy was referred to our clinic due to PVCs and paroxysmal VTs observed by 24‐­hour Holter monitoring after interventional closure of ventricular septal defect for 2 months. The Holter monitoring revealed a total number of 41644 PVCs within 24 hours, comprising 31.5% of total heart beats. radiofrequency catheter ablation was performed to maintain the sinus rhythm. Under the fluoroscopic guidance, XXF catheter was inserted into femoral artery and positioned at aortic sinus (AS).

Result:

Early activation was spotted in left coronary cusp (LCC) 65 ms pre‐­QRS with a near perfect pace mapping (97% concordance). Ablation was carried out in the LCC with power set to 10 W and maximum temperature to 55°C for 60 seconds around the spot. PVCs disappeared after 6 s and were not induced by isoproterenol. The whole procedure lasted for 55 minutes, with fluoroscopic exposure dose of 33 mGy. The patient was discharged 48 hours with no complication and remained asymptomatic 12 months after the ablation.

Conclusion:

In pediatric patients, late onset of frequent PVCs and paroxysmal VTs is a rare complication after trans‐­catheter VSD closure. Radiofrequency ablation is efficacious and safe in terminating the arrhythmias and maybe preferred over medical therapy for fewer side effects and better patient compliance.

AP19‐­00793

An unusual incessant narrow QRS tachycardia

Vivek Chaturvedi, Hemant Madan, Rajni Sharma

Narayana Superspeciality Hospital, India

Introduction:

We describe an unusual incessant narrow QRS tachycardia in a young man. A 29 years old man presented with incessant narrow QRS tachycardia, resistant to all anti‐­arrhythmics and repeated electric cardioversion. He had no other significant history and his echocardiogram was normal.

Methods:

During electrophysiology study (EPS), he had an ongoing tachycardia at 150 bpm (1A) with right axis deviation, QRS width of 110 ms, HV interval of 26 ms, and distal his EGM preceding the proximal his (1B). There was ventriculo‐­atrial dissociation with cranio caudal activation of right atrium (Figure 1B). The tachycardia broke for a single beat, and the HV interval increased to 55 ms with only a subtle change in QRS morphology (Figure 1C). On mapping proximal and mid left ventricular septum (LVS) with decapolar catheter, ventricular EGM were preceded by purkinje potentials in tachycardia with base to apex activation pattern (Figure 1E). P 1 diastolic potentials were also noted with opposite activation pattern (Figure 1D). Entrainment of tachycardia was not contributory.

Result:

A diagnosis of upper septal type of fascicular VT was made and further mapping done with ablation catheter. During mapping of upper LVS, several large amplitude diastolic potential were noted. As soon as ablation was started, an ablation catheter induced ectopic terminated the tachycardia and sinus rhythm resumed thereafter (Figure 1F). Several consolidation burns were given in the adjoining areas carefully (1G‐­II) and after this the tachycardia was not inducible despite several provocative maneuvers on isoprenaline. At follow up of 3 months, he was asymptomatic off all medications.

Conclusion:

We have described an unusual refractory incessant upper septal variant of fascicular VT. During EPS, a fortuitous finding of increase in HV interval, when tachycardia broke to sinus rhythm for a single beat, clinched the diagnosis of VT.

AP19‐­00800

Zero fluoroscopy ablation for ventricular tachycardia

Tohru Kawakami, Naoki Saitou, You Asukai, Shinya Wada, Houjou Sasaki, Hideo Takahashi, Kei Hatori, Noritoshi Itou, Hiroshi Fukunaga, Tetuya Toubaru

Kawasaki Saiwai hospital, Japan

Introduction:

Radiofrequency catheter ablation is an effective treatment option for ventricular tachycardia (VT). There is a concern that VT ablation may cause longer fluoroscopy time. Exposure to radiation during catheter ablation procedures is a risk for both the patient and electrophysiology staff. Recently, the feasibility and effectiveness of zero fluoroscopy ablation has been shown. There are some strategy to VT ablation. We present our experience with a strategy isolating core elements of VT circuits (core isolation) with zero‐­fluoroscopy technique.

Methods:

Zero fluoroscopy ablation was performed in 2 patients with VT using a 3‐­dimensional electro‐­anatomical mapping system, contact force monitoring, and intracardiac echocardiography imaging. In these cases, ultrasound‐­guided sheath insertion (9 Fr sheath and 8.5 Fr sheath) was performed from the right femoral. The strategy of VT ablation was isolating core elements of VT circuits (core isolation). An ablation catheter was advanced to the left ventricle anterograde or retrograde and a voltage‐­map was created under pacing rhythm or sinus rhythm. Core isolation was performed around the low voltage zone. The end point of core isolation was exit block within the isolated area. VT induction test was conducted after core isolation.

Result:

Case 1 was a 62‐­year‐­old man with old myocardium infarction. He had a history of aortic valve replacement, coronary artery bypass grafting, and CRTD implantation. He was an emergency hospitalization due to VT storm. After core isolation, VT was not induced, and the treatment ended without complications. Case 2 was a 65‐­year‐­old man with old myocardium infarction. He had a history of ICD implantation. An ablation catheter was advanced anterogradely to the left ventricle and a voltage‐­map was created under pacing rhythm. Core isolation was performed around the low voltage zone. There were no complications related to procedures. Fluoroscopic time during the ablation procedure was 0 seconds. No serious procedure‐­related complications were recorded. Two cases have been followed up by remote monitoring system without VT.

Conclusion:

Zero fluoroscopy VT ablation is feasibility. Endocardial VT ablation using zero fluoroscopy technique may eliminate radiation exposure. Core isolation is a strategy with a discrete and measurable endpoint.

AP19‐­00803

Predictive value of big‐­endothelin‐­1 for SCD and all cause mortality in heart failure patients of Asian HF study

Xiaoyao Li

Fuwai Hospital, China

Introduction:

Serum concentration of big endothelin‐­1 (ET‐­1) has prognostic significance in heart failure. However, its prognostic value in sudden cardiac death has not been well‐­characterized. The present study is to investigate the association between big endothelin‐­1 and major adverse cardiovascular events in heart failure patients.

Methods:

A total of 187 patients with heart failure in Asian HF study were included in the present study, and followed up till the end of January 2016. The patients were divided into three groups according to the levels of serum big endothelin‐­1: the group 1 (0.25‐­0.44 pmol/L, n = 61), the group 2 (>0.44‐­<0.83 pmol/L, n = 63), and the group 3 (>0.83 pmol/L, n = 63). The primary endpoint was sudden cardiac death, secondary endpoint was composited of heart transplantation and all cause mortality.

Result:

During a mean follow‐­up period of 18.49 ± 9.67 months, 22 patients (11.8%) experienced SCD. 63 patients (16.8%) died or underwent heart transplantation. As determined by Kaplan‐­Meier analysis, the risk of composited secondary endpoint increased according to serum big endothelin‐­1 level (41% vs 57.1% vs 71.0%, Group 1‐­Group 3, P < .001). In multivariate COX regression models, big‐­ endothelin‐­1 was an independent risk factor for heart transplantation and all cause mortality (HR 3.130, 95% CI: 1.320‐­7.421, P = .010, Group 2 vs Group 1; HR 5.339, 95% CI: 2.303‐­12.376, P < ..001, Group 3 vs Group 1). As for SCD, only group 2 but not group 3 held higher risk of SCD (HR 4.648, 95% CI: 1.294‐­16.694, P = .019, Group 2 vs Group 1)

Conclusion:

Serum big endothelin‐­1 level showed good predictive efficacies for heart transplantation and all cause mortality. When big endothelin‐­1 exceeds a certain level, non‐­cardiac deaths increase.

AP19‐­00806

No difference in ATP success for terminating monomorphic VT between primary and secondary prevention patients

Takashi Kurita, Yan Zhang, Daniel Lexcen, Shelby Li, Mark L Brown

Gadjah Mada University, Indonesia

Introduction:

Anti‐­tachycardia Pacing (ATP) success rate has been shown to be between 50 and >90% successful in different studies depending on episode rate, time to detection and whether analysis is limited to only episodes adjudicated as monomorphic VT (MVT). Older studies showed that VT/VF event rates were higher for secondary prevention compared to primary prevention patients with similar ATP success. In the modern era with improved medical therapy, little data exists on ATP success stratified by indication. We re‐­evaluated the ATP success rate for terminating MVT using the PainFree SST clinical trial where all VT/VF episodes were adjudicated by an independent Episode Review Committee.

Methods:

Ventricular tachycardia episodes that were classified as MVT were included for the analysis. ATP success was defined as MVT episodes terminated by ATP. ATP success rate and its 95% confidence interval (CI) were calculated for specific device types, indications and episode detection zones using the Generalized Estimating Equations (GEE) method.

Result:

Of the 2770 enrolled patients (79% male, average age 65 years), 1071 (39%) were implanted with an ICD and 1699 (61%) were implanted with a CRT‐­D system; 1917 (69%) were reported as primary prevention and 847 (31%) were secondary prevention patients. Of 1917 primary prevention patients, 160 (8.3%) had 631 ATP treated MVT for which ATP was successful 76.8% (95% CI: 71.2%‐­81.6%). Of 847 secondary prevention patients, 212 (25.0%) had 1616 ATP treated MVT for which ATP was successful 84.3% (95% CI: 80.6%‐­87.5%). The difference in ATP success rate between primary and secondary prevention patients was not statistically significant (P = .14). ATP was successful 89.0%, 72.4% and 67.9% in the VT, FVT and VF zones, respectively (P = .0001).

Conclusion:

Though VT/VF episodes are more common in secondary vs primary prevention patients, ATP success rate is not significantly different between the two groups. On the other hand, ATP success rate differs significantly by zones (rate in order: VT>FVT>VF).

AP19‐­00819

The electrocardiographic characteristics, presence of J‐­waves, and torsade de pointes with hypothermia

Minoru Tarawa, Masaomi Chinushi, Yukie Ochiai, Makoto Tomita, Takumi Akiyama, Yoshifusa Aizawa

Nagaoka Chuo General Hospital, Japan

Introduction:

The occurrence of a J wave (Osborn wave) with hypothermia is well known, but the relationship of J waves and torsade de pointes (TdP) with hypothermia has not yet been clarified.

Methods:

In this study, 66 consecutive patients (31 men; mean age, 74 ± 16 years) were admitted to our hospital with accidental hypothermia, and were classified into 3 groups according to rectal temperature upon arrival in the emergency room (group A: 33–35°C, group B: 30–33°C, and group C: under 30°C). ECG was recorded on admission, and the ECG parameters, including J‐­waves, were compared with the patient's clinical data and courses. Special attention was paid to the ECG characteristics of the patients who had TdP.

Result:

Consciousness disorders were observed in 8 of 13 patients in group A, in 7 of 16 patients in group B, and in 36 of 37 patients in group C (P < .0001). Heart rate was slower in group C than in groups A and B (group A: 81.2 ± 26.3 bpm, group B: 75.6 ± 26.7 bpm, and group C: 51.7 ± 21.0 bpm [P = .0002]). Although ECGs showed sinus rhythm in 12 of the 13 patients in group A and in 12 of 16 patients in group B, bradycardiac atrial fibrillation or junctional rhythm was observed in 24 of the 37 patients in group C (P = .0002). J waves (slurs or notches ≥0.1 mV in amplitude) were observed in 31 of 37 patients in group C and in 5 of 16 patients in group B, but in only 1 of 13 patients in group A (P < .0001). QRS duration was longer in group C than in group B and A, and QT interval were longer in group C than in groups B (QRS duration; group A: 103.2 ± 11.3 ms, group B: 105.5 ± 13.7 ms, and group C: 142.3 ± 34.3 ms [P < .0001]; QT interval: group A: 426.2 ± 59.7 ms, group B: 447.1 ± 75.3 ms, and group C: 564.7 ± 93.7 ms [P < .0001]). No significant differences in laboratory blood results were found among the three groups. Rate‐­dependent changes in the J wave amplitude were observed in 19 patients, and all 19 patients were belonged to group C. TdP was observed in 3 patients in group C. The ECGs of these 3 patients showed atrial fibrillation with bradycardia, and rate‐­dependent changes in the J‐­wave amplitude.

Conclusion:

ECG characteristics, including J waves, were affected by rectal temperature in the patients with accidental hypothermia. TdP developed in 3 of 66 patients (4.5%), who also had J waves demonstrating heart rate‐­dependent variations and atrial fibrillation with slow ventricular rates.

AP19‐­00821

Periprocedural acute kidney injury in patients with structural heart disease undergoing catheter ablation of ventricular tachycardia: Incidence, predictors and impact on outcomes

Ling Kuo, Daniele Muser, Yasuhiro Shirai, Robert D. Schaller, Matthew Hyman, Ramanan Kumareswaran, Jeffrey Arkles, Gregory E. Supple, David S. Frankel, Fermin Garcia, Cory Tschabrunn, Saman Nazarian, Sanjay Dixit, David Lin, Michael P. Riley, David, J Callans, Rajat Deo, Andrew Epstein, Erica S. Zado, Francis E. Marchlinski, Pasquale Santangeli

Hospital of the University of Pennsylvania, United States

Introduction:

Catheter ablation of ventricular tachycardia (VT) in patients with structural heart disease has risk of significant periprocedural hemodynamic derangements, which may affect end‐­organ perfusion and precipitate acute kidney injury (AKI). The clinical significance of periprocedural AKI in patients with structural heart disease undergoing VT ablation has not been previously investigated. This study sought to examine the impact of periprocedural AKI in patients with structural heart disease undergoing VT ablation.

Methods:

We included a total of 317 consecutive patients with structural heart disease (age 64 ± 13 years, mean LVEF 33 ± 13%, 55% ischemic cardiomyopathy) undergoing catheter ablation of VT at our institution between 2010 and 2013, who had serial assessments of serum creatinine levels pre‐­ and post‐­procedure. Ablation was guided by activation/entrainment mapping for tolerated VT and pacemapping/targeting of abnormal electrograms for unmappable VT. Periprocedural AKI was defined as an absolute increase in creatinine of ≥0.3 mg/dL within 48 hours or an increase of ≥1.5 times the baseline values within 1 week post‐­procedure.

Result:

Periprocedural AKI occurred in 31 (10%) patients. Predictors of AKI included atrial fibrillation (OR 3.74, 95% CI 1.66‐­8.42, P = .001), periprocedural acute hemodynamic decompensation (OR: 5.04, 95% CI 1.76‐­14.40, P = .003), and use of angiotensin converting enzyme inhibitor/angiotensin II receptor blockers (OR 3.11, 95% CI 1.16‐­8.38, P = .024). After a median follow‐­up of 39 months (interquartile range 6‐­65 months), 95 (30%) patients died. Periprocedural AKI was associated with increased risk of early mortality (within 30 days, hazard ratio [HR] 9.91, 95% CI 2.87‐­34.27, P < .001) and late mortality (within 1 year) following the procedure (HR 3.81, 95% CI 1.77‐­8.20, P = .001) (Figure). After multivariable adjustment, AKI remained independently associated with increased risk of early and late mortality (HR 7.99, 95% CI 2.13‐­29.93, P = .002 and HR 2.95, 95% CI 1.25‐­7.00, P = .014, respectively).

Conclusion:

Periprocedural AKI occurs in at least 10% of patients with structural heart disease undergoing VT ablation, and is strongly associated with increased risk of early and late post‐­procedural mortality. Serial assessments of kidney function following the procedure should be considered in this population, and defining strategies to minimize the risk of periprocedural AKI is crucial.

AP19‐­00830

General anesthesia reduced ventricular tachycardia inducibility in outflow track ventricular tachycardia ablation: local vs general anesthesia

Haikal Haikal

Binawaluya Cardiac Center, Indonesia

Introduction:

General anesthesia (GA) is commonly not being done in ventricular arrhythmia ablation because of its effect on reduced sympathetic responses in the occurrence of ventricular arrhythmias.

Methods:

A 55‐­year‐­old general physician came to our hospital with a chief complain of palpitation. ECG showed sinus rhythm and frequent premature ventricular contraction (PVC) with inferior axis, qR pattern in lead V1, absence of S wave in lead V5 or V6 and no transition zone. Holter monitoring showed non‐­sustained VT. Radio frequency ablation was performed using 3‐­D mapping and under GA. Aggressive programmed stimulation and intravenous isoproterenol could not induce VT after ablation. However, holter monitoring post procedure showed no significant reduction of PVC burden with the same morphology. Second attempt of ablation was performed without GA. Aggressive programmed stimulation and intravenous isoproterenol also could not induce VT after ablation. Second holter monitoring evaluation post procedure showed significant reduction of PVC burden

Result:

Radiofrequency ablation of ventricular tachycardia maybe better perform without GA.

Conclusion:

Radiofrequency ablation of ventricular tachycardia maybe better perform without GA.

Keywords: General anesthesia, local anesthesia, ventricular tachycardia ablation.

AP19‐­00845

Accuracy of non‐­invasive mapping for premature ventricular complexes catheter ablation in a heterogeneous cohort of patients

Ilaria Cazzoli, Silvia Guarguagli, Sabine Ernst

Royal Brompton Hospital Trust, United Kingdom

Introduction:

A novel non‐­invasive three‐­dimensional (3D) mapping software shows the unique feature of combining 3D DICOM data with 12‐­lead electrocardiographic (ECG) data to precisely localise ventricular arrhythmias. This allows to “move” the localisation diagnosis to the ward prior to the invasive cath lab procedure and is especially helpful in patients with polymorphic premature ventricular complexes (PVCs). Its accuracy to localize PVCs and guide catheter ablation has been already demonstrated in previous studies. However, all previously recruited patients had structurally normal hearts (<10% of scar burden). We aimed to challenge the non‐­invasive 3D mapping software accuracy in a different and more challenging patient population with structural heart disease and >10% of scar burden.

Methods:

Seventeen consecutive patients (10F, mean age 48 ± 17 years) were studied. Underlying cardiac conditions were: 7 (41.2%) patients with congenital heart disease of moderate severity (Bethesda 2), 2 patients (11.8%) with dilated cardiomyopathy, 1 patient (5.9%) with Brugada syndrome, 6 patients (35.3%) with structurally normal heart and <10% of scar burden, and lastly one (5.9%) with structurally normal heart but severe ischaemic disease. For all, a 3D personalised model of the heart and torso were generated from either cardiac magnetic resonance imaging or computed tomography scans. This was merged with a 3D picture of the ECG‐­leads position. Subsequently, digital ECG files of the PVCs or paced beats derived from either 12‐­lead Holter or electrophysiological recording system were imported into the 3D non‐­invasive mapping software for analysis. Finally, the location was compared to the site of ablation on electro‐­anatomical mapping system.

Result:

The non‐­invasive 3D mapping software showed an accuracy of 89.6%, when compared to the electroanatomic system localisation during the procedure, in the 29 ECG locations collected: 11 right ventricular outflow tract (RVOT, 37.9%), 6 endocardial right ventricle (RV, 20.7%), 9 endocardial left ventricle (LV, 31%) (Figure), 3 epicardial LV (10.3%). Overall, 3 paced beats (10.3%), 2 VTs (6.9%) and 24 PVCs (82.7%).

Conclusion:

Accurate non‐­invasive 3D localization of VT/PVCs’ origin was achieved in 89.6% of the analysed samples in a diverse and challenging cohort of patients, including patients with structural heart disease, cardiomyopathy and a scar burden beyond 10%. These promising results suggest a broader` indication for such technology, and should be further validated by prospective trials.

AP19‐­00846

Ablation of VT and associated LAVAs in a patient with ischemic heart disease on ICD device

Muhammad Muqsith, Sunu Budi Raharjo, Dicky Armein Hanafy, Dony Yugo Hermanto, Yoga Yuniadi

Zainoel Abidin General Hospital, Banda Aceh, Indonesia

Introduction:

Ischemic ventricular tachycardia (VT) is still a life‐­threatening arrhythmia caused by the scar of previous ischemic insult. The ablation of this VT remains to be a challenging procedure in the electrophysiology lab. Scars may act as a slow conduction area that will sustain the arrhythmia. Therefore detailed definition of the channels and identification of abnormal potentials are critical for success of substrate ablation. This effort of defining the lesion can be achieved with high density 3D mapping techniques.

Methods:

Herein, we report a 50‐­year‐­old male cardiac arrest survivor with ischemic heart disease on ICD and underwent ablation therapy due to a VT storm, with excessive appropriate ICD shocks. EF was 44% with akinetic inferior‐­ and posterior segment. High density voltage mapping in sinus rhythm using Pentaray catheter and the Carto 3 version 6 system revealed large scar area in the inferior segment spanning from basal to apical area. We identified a significant low voltage area exhibiting channels in the scar areas. In addition, several type of LAVAs (fractionated potential, late potential and split potential) were found in those areas, spread across the inferoseptal up to posterior area. Next, we induced the clinical VT under sedation. The VT was RBBB‐­type, superior axis, and negative lead I. Activation mapping indicated that the VT exit was in the basal posterior segment.

Result:

The exit area and LAVAs were successfully ablated. Subsequently, the VT became non‐­inducible and the patient remained free of VT during follow up.

Conclusion:

This report shows the importance of VT and LAVA ablation in the patient with ICD‐­implanted ischemic VT storm. To achieve that, high density mapping are important in identifying the exit site and VT channels for effective ablation site, which will permanently terminate the VT storm.

AP19‐­00852

The use of a high‐­density grid‐­style mapping catheter in catheter ablation of ventricular arrhythmias

Shinji Kaneko, Yasunori Hiranuma, Takeshi Matsuura, Seiichirou Matsuo, Satoshi Shizuta, Kazuya Yamao, Fumiharu Miura, Satoru Sakagami, Naoyuki Miwa, Taku Asano, Caroline Tao, Shunichiro Warita

Abbott, United States

Introduction:

High‐­density mapping catheters may provide benefit across a spectrum of cases, from simple paroxysmal atrial fibrillation to complex ventricular tachycardia (VT). Fast and accurate point collection to create reliable electroanatomic maps is especially critical during VT procedures. Utilization of a high‐­density, grid‐­style mapping catheter in combination with automated mapping software and the HD Wave configuration has been reported to reliably collect a high density of points and confirm effective isolation rapidly. Here, procedural characteristics were examined in VT cases using a high‐­density, grid‐­style mapping catheter in a Japanese population.

Methods:

Procedural data was collected for VT cases utilizing a high‐­density, grid‐­style mapping catheter from 12 participating centers in Japan. Procedural data including electrode configuration, mapping time, AutoMap setting, points acquired, ablation targets, and acute outcomes were recorded.

Result:

Procedural data from 16 VT (11 premature ventricular contraction (PVC), 3 idiopathic, and 2 ischemic) cases were collected from September to December 2018 in Japan. De novo ablation accounted for the majority of the cases (12 de novo, 4 redo). Documented ablation locations in descending order were RVOT (4 PVC, 2 idiopathic), LV (3 PVC, 2 ischemic), LVOT (4 PVC), and RV (1 idiopathic). Retrograde access was used in 9 cases (6 PVC, 1 idiopathic, 2 ischemic) and only 1 transseptal access was reported. The AutoMap module was utilized in 14 cases (11 PVC, 1 idiopathic, and 2 ischemic). Maps were created in sinus rhythm for all but one case (idiopathic). While a voltage map was used to define ablation strategy in the two ischemic VT cases; all PVC and idiopathic VT cases used the LAT map. The HD Wave electrode configuration, which accounts for directionality by collecting data exclusively from orthogonal bipoles, was used in all but one ischemic VT case. Overall, an average of 7630.9 points were collected in 23.1 minutes (330.3 points/min) from the 15 VT cases utilizing the HD wave configuration during mapping. Acute procedure success was reported in 13 cases (4 no inducible VT, 2 elimination of clinical VT, and 7 no recurrent PVC).

Conclusion:

While the ablation location, mapping and procedural time vary from case to case for VT ablation, the application of this high density, grid‐­style mapping catheter is highly versatile. In PVC, idiopathic and ischemic VT ablation, the primary locations for ablation were RVOT and LV with over 81% acute procedural success when the high density, grid‐­style mapping catheter was used.

Table Procedural characterizes collected from 15 ventricular arrhythmia cases utilizing grid‐­style mapping catheter and HD Wave configuration

AP19‐­00862

Long‐­term outcome of catheter ablation for ventricular tachycardia in patients with post myocardial infarction with heart failure in mid‐­range ejection fraction term

Shin Nakamura, Takeshi Kitamura, Soichiro Maeda, Shihoko Tsujihata, Koichiro Yamaoka, Kosuke Takeda, Tomoyuki Arai, Kohei Kawajiri, Sho Tanabe, Sayuri Tokioka, Yasuki Koyano, Dai Inagaki, Kiyotaka Yoshida, Iwanari Kawamura, Takeshi Kitamura, Rintaro Hojo, Takashi Shibui, Seiji Fukamizu

Tokyo Metropolitan Hiroo Hospital, Japan

Introduction:

Background: Ventricular tachycardia (VT) is a fatal arrhythmia that causes sudden death in patients with heart failure (HF). It is well known that patients who have low left ventricular (LV) ejection fraction (EF) show unfavorable outcomes after VT ablation. Recently, the classification of HF by LVEF has been renewed (Heart Failure reduced EF (HFrEF) [EF < 40%], HF mid‐­range HF (HFmrEF) [40% =< EF < 50%], HF preserved EF (HFpEF) [EF >= 50%]). However, no reports are available on the effectiveness of catheter ablation for VT in patients categorized using the updated classification, in particular of the HFmrEF group Objective: The purpose of this study was to evaluate the outcome after initial ablation for post‐­myocardial infarction (MI) VT in patients classified in the 3 groups divided by the updated classification of HF (HFrEF, HFmrEF, HFpEF).

Methods:

Methods: We enrolled patients with post‐­MI who underwent initial VT ablation. Enrolled patients were divided into 3 groups (HFrEF group, HFmrEF group, HFpEF group) by EF as defined above. Then, we retrospectively analyzed patients characteristics and evaluated VT recurrence after ablation. The outcome of HFmrEF group was compared with that of HFrEF or HFpEF.

Result:

Results: Sixty‐­seven cases were analyzed (HFrEF, n = 41; HFmrEF, n = 13; HFpEF, n = 13). The mean age was not significantly different among the 3 groups (67 ± 12, 66 ± 15, 72 ± 17, respectively). The average EF was significantly different among 3 groups (30 ± 12%, 44 ± 15% and 56 ± 13%, respectively P < .001). The rate of HFmrEF patients in whom implanted ICD or CRTD was not significantly different from HFrEF, however lower than that of HFpEF (71%, 77%, 38%). Mean follow‐­up period was 2.5 ± 1.8 years. In Kaplan‐­Meier analysis, the outcome of HFmrEF group did not differ from that of the HFrEF group in VT recurrence during the follow‐­up (Log‐­rank = 0.652), and the HFmrEF group tended to have a higher VT recurrence rate than the HFpEF group (Log rank = 0.07). In terms of mortality after VT ablation, the mortality of HFmrEF group did not differ from that of the HFpEF group during the follow‐­up (Log‐­rank = 0.361), and was lower than that of the HFrEF group (Log rank = 0.019).

Conclusion:

The HFmrEF group tended to have a higher VT recurrence rate than the HFpEF group, and comparable recurrence rate to the HFrEF group. The HFmrEF group showed higher mortality than the HFrEF group, and comparable mortality to the HFpEF group.

AP19‐­00863

Endo‐­Epicardial mapping for ventricular tachycardia based on old myocardial infarction to identify tachycardia circuits involved intramural myocardium: A case report

Tomoyuki Arai, Seiji Fukamizu, Soichiro Maeda, Shihoko Tsujihata, Kosuke Takeda, Shin Nakamura, Koichiro Yamaoka, Kohei Kawajiri, Sho Tanabe, Yasuki Koyano, Sayuri Tokioka, Iwanari Kawamura, Takeshi Kitamura, Rintaro Hojo

Tokyo Metropolitan Hiroo Hospital, Japan

Introduction:

Radiofrequency catheter ablation is a therapeutic option for recurrent ventricular tachycardia (VT) in ischemic cardiomyopathy. Usually endocardial mapping is performed for ablation of the VT in patients with old myocardial infarction (OMI); however, in some cases, epicardial mapping may be required to identify tachycardia circuits that can only be explained in three dimensional (3D) rather than 2D. We report a case in which epicardial approach was used to successfully ablate the VT involving an intramural/epicardial substrate.

Methods:

N/A

Result:

A 66‐­year‐­old man who had a history of anterior‐­septal OMI visited our hospital for respiratory distress. We did cardioversion because electrocardiogram indicated monomorphic ventricular tachycardia (VT). Electrophysiological study and catheter ablation for monomorphic VT were performed. Voltage map of left ventricle (LV) during right ventricular (RV) pacing indicated that there was scar and low voltage area from the LV septum to the apex. Activation map of the LV for induced VT1 (LBBB/superior, TCL 320 ms.) showed a centrifugal pattern from the apical septal wall and local activation time did not cover for tachycardia cycle length (TCL) of VT1. Entrainment pacing revealed that the post pacing interval (PPI) from a centrifugal pattern point of LV endocardium exceeded the TCL by 20 ms with manifest fusion. VT1 was terminated by ablation of that site; however, VT2 (RBBB/superior, TCL 340 ms) was induced. Because there is no evidence for the endocardial circuit of VT1, we tried to evaluate VT2 from both the endocardium and the epicardium. We created an activation map of VT2 from the epicardium by subxiphoid approach. The earliest activation site was at the left ventricular apex, and then the excitation propagation was directed to the base of the anterior wall, exciting the conduction delay site of the anterior wall as a figure of eight. Despite adding the endocardial mapping, the endocardial and epicardial activation did not cover all phases of the tachycardia, and the epicardial reentry with partial intramural circuit was suspected. Unfortunately, the VT2 changed to VT3 (RBBB/superior, TCL 330 ms) during mapping without detailed pacing evaluation. The propagation of VT3 showed that a tachycardia circuit in which the activation sequence of “common channel” was reversed to that of VT2. This epicardial common channel site was ablated during VT3, and the tachycardia stopped. After that, the procedure was terminated without being induced any VT by programmed stimulation.

Conclusion:

We experienced that, as VT based OMI, endocardial and epicardial approach were effective to identify 3D reentrant circuit of VT, where involvement of intramural site. Adding epicardial mapping and ablation may improve outcomes for ischemic VT involving intramural/epicardial circuit.

AP19‐­00881

Superiority of contact force catheter for ablation of outflow tract ventricular arrhythmia

Vikas Kataria, Vipul Malpani, Mohan Nair, Amitabh Yaduvanshi, Gautam Singal, Pritam Kittey

Holy Family Hospital, India

Introduction:

Poor catheter to myocardium contact may lead to ineffective ablation lesions and suboptimal outcome. Contact Force (CF) Ablation catheter provides promising way to overcome this problem. Data on use of Contact Force (CF) ablation catheters in ventricular arrhythmia (VA) is limited. We evaluated safety and efficacy of CF ablation of Outflow Tract VA.

Methods:

All patients with outflow tract VA, who were subjected to Radio Frequency Ablation (RFA) over a period of 2 years using irrigated catheter with or without contact force formed the study population. They were grouped into CF or Non CF group according to the type of catheter used. All patients were followed up with clinically and by Holter monitoring for 6 months after the procedure.

Result:

Forty patients underwent RFA for outflow tract VA between May 2017 to April 2019. In 20 patients(CF group) irrigated ablation catheter with CF was used for RFA (Tacticath™, St Jude Medical) (40 W, 40°C, 17 mL/cc, 10‐­30 gm) and 20 patients (NCF group) underwent RFA with irrigated catheter without contact force sensing (Flexibility, SJM 40W, 40°C, 17 mL/cc).Baseline characteristics and results are shown in table. All patients in both the groups underwent successful RFA of VT defined as non inducibility at the end of procedure. There were no procedural complications and no in‐­hospital recurrence of arrhythmia. Total 7 patients in NCF group and 1 patient in CF group had recurrence of VA for which they required hospitalization and repeat procedure. Four patient in NCF group and zero in CF group were detected to have asymptomatic recurrence of VPC's on Holter (>10% VPC burden) (P < .05).

Conclusion:

Use of CF sensing catheter is safe and effective in the RF ablation of outflow tract VT. It can be an effective tool to prevent recurrence of arrhythmia in this subgroup of patients.

Table

Patient characteristics	Contact force catheter group N=20	Non contact force catheter group n=20	P value
Mean age	61.7 ± 11 years	62.9 ± 8.4 years	Not significant
Males	60%	60%	Not significant
Structural heart disease	0%	0%	Not significant
LV ejection fraction	55.2 ± 12.1 %	55.3 ± 9.9 %	Not significant
Complications during ablation	Nil	Nil	Not significant
Non inducibility at end of RFA	100.00%	100.00%	Not significant
In hospital VT recurrence	Nil	Nil	Not significant
Symptomatic recurrence of VT requiring repeat procedure	1	3	Not significant
Asymptomatic recurrence of VA (on Holter)	Nil	4	(P = .107)
Total recurrence	1	7	(P ˂ .05)

AP19‐­00883

Ultrasound guided percutaneous left stellate ganglion block for ventricular arrhythmia storm in acute coronary syndrome following percutaneous coronary intervention: A case series

Kotti K, Jaya Pradhap, Radhika B, Aishwarya S, Sabari S, Mahima P Manoj, Nithin G, Sailendri G, Benjamin S, Ravi Kumar, Nirmala S, Dasari Himaja, Sandini S, Swathi K, Ulhas M Pandurangi

The Madras Medical Mission, India

Introduction:

Electrical storm may not be responsive to anti‐­arrhythmic drug (AAD) therapy. Heightened sympathetic tone plays a critical role in the initiation and maintenance of ventricular arrhythmia (VA) storm. There is a paucity of data regarding efficacy of an easily performable bed‐­side ultrasound guided (USG) left stellate ganglion block (SGB) in acute coronary syndrome.

Methods:

Characteristics of 11 patients who underwent bed‐­side USG‐­guided left SGB for VA storm were analyzed. Known cases of coronary artery disease and past history of myocardial infarction were excluded. Left SGB was performed under ultrasound guidance using a 7.5 MHz 9L‐­D broad‐­spectrum linear transducer probe (GE vivid S70 ultrasound machine). In the supine position with slightly extended neck the Chassaignaic tubercle was located. The site was anaesthetised avoiding the vessels by Doppler images with 5 cc of 2% Lignocaine and 5 cc 0.5% Bupivacaine lidocaine using a 7 cm long 22 gauge needle, directed towards the longus colli muscle medial to the common carotid artery and jugular vein. The procedure was repeated after 24 hours including right stellate ganglion block if storm persisted.

Result:

All patients in VA storm received at least one intravenous and one oral AAD and multiple DC shocks before the procedure. Acute ST elevation myocardial infarction (STEMI) in eight, NSTEMI in two and unstable angina in one patient. The mean age and LVEF were 57 ± 14.8 years and 35 ± 6.2% respectively. All patients underwent percutaneous coronary intervention (PCI) and had VT storm after 48 hours of PCI. The mean number of AAD and DC shocks given were 1.8 ± 1.2 and 3 ± 1 respectively. All patients were free of VA storm for a mean of 1.3 ± 1.7 days. Four patients underwent VT ablation as a rescue therapy. Eight patients were implanted with ICD in the follow‐­up. Two patients died of refractory VA storm despite second attempt of SGB and one patient with heart‐­failure. Horner syndrome was present in all patients after SGB and recovered later. Local site hematoma occurred in 1 patient. Repeat SGB and right SGB were required in 2 and 1 patient respectively.

Conclusion:

Bed‐­side USG guided SGB is an effective and easily performable strategy to overcome VA storm in acute coronary syndrome.

AP19‐­00888

Carotid baroreceptor stimulation suppresses ventricular fibrillation in canines with chronic heart failure

Mingwei Bao, Mingyan Dai, Jing Wang, Quan Cao, Yijie Zhang, Qiao Yu, Qiang Luo

Renmin Hospital of Wuhan University, China

Introduction:

Malignant ventricular arrhythmias (VAs) is common and confers a substantial risk of mortality and morbidity in patients with chronic heart failure (CHF). The autonomic nervous system is validated to play a significant role in the genesis and maintenance of VAs. Carotid baroreceptor stimulation (CBS) modulates the autonomic nervous system by sympathetic suppression as well as vagal enhancement. Our previous study found long‐­term moderate‐­level CBS (ML‐­CBS) that decreased blood pressure (BP) improved cardiac dysfunction and reduced cardiac fibrosis and apoptosis by inhibiting myocardia intracellular PKA signaling pathway in CHF canines. In addition, we found low‐­level CBS (LL‐­CBS) without BP reduction exhibited anti‐­atrial arrhythmic potential by inhibiting left stellate ganglion (LSG) activity in 6‐­hour rapid atrial pacing canines. In this study, we further investigated the effects of LL‐­CBS and ML‐­CBS on ventricular electrophysiological properties and ventricular vulnerability to fibrillation in CHF canines and its underlying mechanism.

Methods:

Thirty‐­eight beagles were randomized into control (CON, n = 8), CHF (n = 10), LL‐­CBS (n = 10) and ML‐­CBS (n = 10) groups. The CHF model was established by 6‐­week rapid right ventricular pacing (RVP), concomitant LL‐­CBS and ML‐­CBS were applied in the LL‐­CBS and ML‐­CBS group, respectively. After 6‐­week RVP, ventricular electrophysiological parameters, LSG neural activity and function were measured. Autonomic neural remodeling in LSG and left ventricle (LV), ionic remodeling in LV were detected.

Result:

After 6‐­week RVP, compared with CHF group, both LL‐­CBS and ML‐­CBS decreased spatial dispersion of action potential duration (APD), suppressed APD alternants, reduced ventricular fibrillation (VF) inducibility, as well as inhibited enhanced LSG neural discharge and function. Only ML‐­CBS significantly inhibited ventricular effective refractory period and APD prolongation and increased VF threshold. Moreover, ML‐­CBS inhibited the increase in growth associated protein‐­43 and tyrosine hydroxylase‐­positive nerve fiber densities in LV, increased acetylcholinesterase protein expression in LSG, and decreased nerve growth factor protein expression in LSG and LV. Chronic RVP resulted in remarkable reduction in proteins expression encoding for both potassium and L‐­type calcium currents, these changes are partly amended by ML‐­CBS and LL‐­CBS.

Conclusion:

CBS suppressed VF in CHF canines, potentially by modulating autonomic nerve and ion channels. And the effects of ML‐­CBS on ventricular electrophysiological properties, autonomic remodeling and ionic remodeling were superior to that of LL‐­CBS.

AP19‐­00897

VT storm with 6 morphologies of VT

Muhammad Yamin, Simon Salim, Angga Pramudita, Resultanti Irwan Muin, Fidiaji Hiltono, Mohamad Syahrir Azizi, Birry Karim, Lusiani Lusiani, Eka Ginanjar, Muhadi Muhadi, Sally Aman Nasution, Ika Prasetya Wijaya, Dono Antono, Marulam Panggabean, Idrus Alwi

Cipto Mangunkusumo National General Hospital, Indonesia

Introduction:

Recurrent episodes of ventricular tachycardia (VT) in patients with structural heart disease are associated with increased mortality and morbidity. Catheter ablation has emerged as a potential therapeutic option either for primary or secondary prevention of these arrhythmias. VT with multiple morphologies pose a challenge for ablation, most of the time targeting the most sustained or frequent first along with LAVA elimination can successfully terminates all VT.

Methods:

N/A.

Result:

A 65‐­year‐­old man with cardiogenic shock, anteroseptal STEMI with continuous VT history, two‐­vessel coronary CAD, acute kidney injury post supportive HD, community‐­acquired pneumonia, hypocalcemia, and occult hepatitis B, was referred to our centre for urgent VT ablation due to VT storm in the last 24 hours. The VT cannot be suppressed using two anti‐­arrhythmias (amiodarone and lidocaine) and sympathetic control by using general anesthesia. On the procedure, patient developed 6 VTs (Figure A), all of which were hemodynamically unstable and needed early cardioversion. We tried to map the most sustainable VT before his hemodynamic was compromised and earliest local activation was identified in 2 VTs (VT4 and VT5) and we ablated LAVA surrounding those areas. (Figure B) After the initial ablation, only PVC was observed with morphology the same with one of the VT. Another ablation targeting LAVA around this PVC render no more VT or PVC observed. (Figure C) Patient was free from VT 48 hours after ablation, but deceased due to SIRS from his low cardiac output condition.

Conclusion:

In the vicinity of multiple VT, ablating the most sustain and perform LAVA elimination along the border zone can help to reduce all VT.

AP19‐­00900

Local signal to guide ablation in almost simultaneous left and right ventricle activation time in a patient with VT storm

Simon Salim, Muhammad Yamin, Rubiana Sukardi, Angga Pramudita, Resultanti Irwan Muin, Fidiaji Hiltono, Mohamad Syahrir Azizi, Birry Karim, Lusiani Lusiani, Arif Mansjoer, Eka Ginanjar, Muhadi Muhadi, Sally Aman Nasution, Ika Prasetya Wijaya, Dono Antono, Marulam Panggabean, Idrus Alwi

Cipto Mangunkusumo National General Hospital, Indonesia

Introduction:

Recurrent episodes of ventricular tachycardia (VT) in patients with structural heart disease are associated with increased mortality and morbidity, despite the life‐­saving benefits of implantable cardiac defibrillators. Reducing implantable cardiac defibrillator therapies is important, as recurrent shocks can cause increased myocardial damage and stunning, despite the conversion of VT/VF. Catheter ablation has emerged as a potential therapeutic option either for primary or secondary prevention of these arrhythmias, particularly in post‐­myocardial infarction cases where the substrate is well defined.

Methods:

N/A.

Result:

A 60‐­year‐­old man with three‐­vessel coronary CAD on ICD, CHF low EF (28.8%) with LV apical thrombus, history of VT/VF on ICD, acute on CKD, and pre‐­diabetes, experienced VT storm and multiple appropriate ICD shocks in 24 hours. VT storm with multiple appropriate ICD shocks during continuous monitoring (Figure B). Being positive in V1, we map the RV first, showing earliest site to be at septal RV, but this earliest LAT did not yield good (>90%) pace‐­mapping. LV mapping was done, showing a near simultaneous earliest activation in the septal LV corresponding to the RV earliest site (Figure C). Local signal in the LV side showed fragmented low potential whereas in the RV side, it was not fragmented (Figure D). Ablation was done in the LV side during VT and terminates the VT within 10 seconds. After ablation to the surrounding LAVA, no VT inducible using RV S1S3 (Figure E). In the last 1 month, the patient only experienced VT 1 time and terminated by ATP (Figure F).

Conclusion:

When we are faced with two equally possible site for ablation, looking for low, fragmented local signal could help to decide which site is better for ablation.

AP19‐­00928

Sixteen months result from radiofrequency ablation of right ventricular outflow tract premature ventricular contractions in National Cardiovascular Centre Harapan Kita, Indonesia

Ahmad Suhaimi Mustafa, Sunu Budhi Raharjo, Dicky Armein Hanafy, Dony Yugo Hermanto, Yoga Yuniadi

National Cardiovascular Centre Harapan Kita, Indonesia

Introduction:

Premature ventricular contractions (PVC) deriving from right ventricular outflow tract (RVOT) ablation has becoming a curative treatment as compared to medical therapy alone in symptomatic patient. Ablation of RVOT PVC does confer high successful rate.

Methods:

We analyzed data from ablation registry in National Cardiovascular Centre Harapan Kita, Indonesia starting from 1st January 2018 to 30th April 2019 with the initial diagnosis of RVOT PVC based on ECG. 100 patients were screened, 10 were excluded due to incomplete data and inaccurate diagnosis. This patient undergone conventional radio‐­frequency ablation (RFA) of RVOT PVC. We assessed successful location of ablation, outcome and recurrence.

Result:

Out of 90 patients, female predominates with 65 patients (72.2%), compared to men 25 (27.8%). Distribution of age undergone RFA were in the range of 40‐­49 and 50‐­59 years (28.9% and 27.8% respectively) while the youngest patient aged 17 years and oldest patient at 68 years. Most common site for RVOT ablation was at anteroseptal RVOT with 48 patients (53.4%), while posteroseptal region in 12 patients (13.3%). Uncommon site of ablation was left ventricular (LV) summit, left coronary cusp (LCC) and right coronary cusp (RCC). We found that 75 patients (83.3%) were successfully ablated, while 8 patients (8.9%) failed and 7 patients (7.8%) had partial success. Failed ablation came from 2 patients with anteroseptal, 2 posterior, each one from free wall and LV summit, while another 2 were undefined RVOT area. From successful ablation group, 67 patients (89.3%) had no recurrence, 8 patients (8%) immediate, and 2 patients (2.7%) delayed.

Conclusion:

From our data, RVOT PVC commonly attributed to anteroseptal region, predominant in female and largely comprised of middle age group. Conventional RFA of RVOT still conferred good successful rate with low recurrence. It could still be first option ablation modality as opposed to 3D ablation due to cost, feasibility and availability.

AP19‐­00929

Concomitant fascicular ventricular tachycardia and total atrioventricular block in mitral valve prolapse syndrome – A therapeutic challenge and dilemma

Rolando Agustian Halim, Raymond Pranata, Fredy Tandri, Alexander Edo Tondas

Mohammad Hoesin General Hospital, Indonesia

Introduction:

Apart from refractory ventricular tachycardias (VT) and the associated sudden cardiac death in mitral valve prolapse (MVP), conduction disorders such as sinus node dysfunction, dual AV physiology, and around 12% of second or third degree atrioventricular block had also been demonstrated.

Methods:

To the best of our knowledge, this is the very first reported case of simultaneous total AV block (TAVB) and fascicular VT in MVP syndrome.

Result:

A 25‐­year‐­old male came with dyspnea on effort and repeated presyncopal episodes since 1 month before admission. Moderate to severe mitral regurgitation due to anterior mitral leaflet prolapse and reduced ejection fraction of 43% were detected from echocardiography. Negative cardiac troponin level excluded the possibility of ongoing acute coronary syndrome or carditis. ECG recording showed TAVB with junctional escape (Figure 1) as the basic rhythm. During palpitations, serial ECGs showed relatively narrow QRS (120‐­140 ms) tachycardias with right bundle branch block (RBBB) pattern and alternating inferior‐­superior axis (Figure 2). AV dissociation during electrophysiology study confirmed both tachycardias as ventricular in origin with at least two reentry circuits. However, mapping of the purkinje potential as ablation target was hindered by ventricular asystole that sometimes followed after intermittent fascicular VTs, therefore we decided to end the procedure and placed a temporary pacemaker. Later, a dual chamber permanent pacemaker was implanted, and the patient was discharged with optimized heart failure medication using ACE inhibitor and diuretics. Fascicular VT episodes seemed to be suppressed quite well by verapamil. Catheter ablation maybe reattempted, preferably with 3 dimensional mapping in case of recurrence.

Conclusion:

The rare association of conduction disorders and MVP is sometimes forgotten in clinical practice. Although the etiology is still unclear, it was thought to be related to a more extensive fibrosis of the mitral valve. At the other end of the spectrum, fascicular VTs are usually verapamil sensitive and amenable to catheter ablation.

AP19‐­00964

Ivabradine: Boon or bane??

Varsha Rakshitha Prakash, Prakash Vadagenalli Sathyanarayanarao

Ramaiah Medical College ana Hospitals, India

Introduction:

Most of the drug‐­induced arrhythmias relate to prolongation of QT interval on the ECG, which can lead to polymorphic ventricular tachycardia (VT) and ‘Torsades de Pointes’ (TdP), which in turn may induce ventricular fibrillation (VF) and sudden death.

Methods:

Objective: To present two cases of Ivabradine causing QT prolongation leading to a VT storm.

Result:

Case report 1 A 70 years old lady, k/c/o IHD‐­status post PTCA presented with features of acute decompensated heart failure. ECG showed sinus tachycardia with LBBB, Echo showed Global hypokinesia of LV with severe LV systolic dysfunction (EF‐­30%). Patient was started on treatment for heart failure. In view of tachycardia, tablet Ivabradine was added. Soon after, patient developed episodes of polymorphic VT. Patient was started on anti arrhythmics and Intra Aortic Balloon Pump (IABP) support for the same, however the episodes of VT continued. In view of suspected drug induced polymorphic VT, tablet Ivabradine was stopped. Patient was also initiated on anti tachycardia pacing which was gradually reduced after 24 hours, following which patient had no further episodes of VT. Patient finally underwent CRT‐­D and was discharged in a stable condition. Case report 2 A 45 years old lady, k/c/o dilated cardiomyopathy presented to the hospital with effort dyspnoea (NYHA class III) on enalapril, bisoprolol and spirolactone long term. ECG done showed sinus tachycardia and underlying LBBB. 2D echo showed dilated LA, LV, severe LV systolic dysfunction EF‐­25% with global hypokinesia. Patient underwent CRT‐­P .On the same day, patient was initiated on Tab Ivabradine 5 mg BD in view of sinus tachycardia. Patient received 6 doses of the same. Two days later patient had sudden onset unresponsiveness. Monitor showed polymorphic VT, patient was defibrillated to sinus rhythm. Patient was put on IABP support & IV esmolol for the VT storm and Tab Ivabradine withdrawn. Patient continued to have recurrent episodes of polymorphic VT. A Bilateral cervical sympathectomy was planned. However, patient died of refractory cardiogenic shock.

Conclusion:

Ivabradine is an If channel blocker, with a half life of 11 hours that leads to a reduction in the slope of the diastolic depolarization of the pacemaker action potential, thereby slowing the heart rate. Studies have shown that the hERG potassium channel inhibition by Ivabradine may contribute to QT prolongation and risk of TdP especially when taken with diuretics or other medicines that prolong the QT interval. In both the above cases, Ivabradine was co administered with diuretics which may have triggered the polymorphic VT. Ivabradine has been given a class IIa indication by the European Society of Cardiology for use in management of symptomatic patients with heart failure with a reduced ejection fraction (HFrEF). However, in view of its life threatening side effects as demonstrated above, it must be used judiciously.

AP19‐­01021

Short PVC coupling interval predicts LV dysfunction in a swine model of ectopy mediated cardiomyopathy

Adam Lee, Tomos Walters, Christina Alhede, Emily Wilson, Richard Sievers, Edward Gerstenfeld

UCSF, United States

Introduction:

We have previously shown in a swine model of ectopy mediated cardiomyopathy (EMC) that greater PVC dyssynchrony and wider QRS were associated with more severe EMC. However, the effect of PVC coupling interval (CI) on EMC is unclear. We aim to determine the effect of PVC CI in a swine model of EMC.

Methods:

Thirteen swine underwent pacemaker implant and were subject to 50% burden of bigeminal PVCs via a lateral CS branch lead to the left ventricle (LV). Pacing occurred at either short (S‐­CI: 320 ms, n = 7) or long (L‐­CI: 410 ms, n = 6) coupling intervals for 12 weeks. S‐­CI animals underwent an additional recovery period of 6 weeks without pacing to study LV recovery. Swine underwent CMR quantification of LV size, function, and strain in sinus rhythm at baseline, at peak cardiomyopathy and after recovery. LV dyssynchrony was quantified as the SD of the time to peak radial strain of 6 segments in the mid‐­LV short axis view.

Result:

There was a significant decline in LV systolic function in the S‐­CI but not the L‐­CI swine; the LV systolic function was significantly lower in S‐­CI compared to L‐­CI after 3 months of bigeminal PVCs [P < .001, Figure 1A]. S‐­CI swine LV function returned to baseline following cessation of bigeminal pacing for 6 weeks. SR LV dyssynchrony increased with S‐­CI but not L‐­CI PVCs (P < .05, Figure 1B) and normalised with recovery. There was a trend towards greater LV dyssynchrony in S‐­CI compared to L‐­CI at 3 months (P = .08).

Conclusion:

In a swine model of EMC, short coupled PVCs from the LV were associated with a greater decline in LV function and dyssynchrony than long coupled PVCs. This suggests short PVC coupling interval is an important mediator of EMC and should be validated in humans.

AP19‐­01028

Ventricular tachycardia in structurally normal heart: QRS‐­T angle ‐­ a novel marker for cardiac sarcoidosis in sinus rhythm ECG

Debabrata Bera, Daljeet Saggu, Calambur Narasimhan

Rabindranath Tagore International Institute of Cardiac Sciences, India

Introduction:

Ventricular tachyarrhythmia (VT), a common manifestation of cardiac sarcoidosis (CS), is associated with high morbidity and mortality. It could be mistaken for idiopathic VT (IVT) in absence of echocardiographic abnormality and systemic symptoms. We studied the electrocardiogram (ECG) characteristics in sinus rhythm (SR) that may distinguish CS from IVT. Objective: We analyzed whether QRS‐­T angle and T wave repolarization abnormalities in sinus rhythm ECG can predict underlying CS.

Methods:

We analyzed the SR ECGS of 50 patients with IVT. All of them underwent cardiac imaging with cardiac PET/CT and contrast‐­enhanced cardiac MRI (CECMR). Twenty‐­five patients had biopsy proven CS (Gr A‐­ cases). Another 25 imaging neg patients with were referred as true IVT (Gr B‐­ controls) (OTVT = 21/fascicular VT = 4). ECG of each patient was analyzed for QRS‐­T angle and T wave in V1/V6, by 2 independent observers who were blinded to the clinical diagnosis.

Result:

Wide frontal QRS‐­T angle {QRS‐­T(f)} was present in 5/25 of cases vs 0/25 controls (P < .0001). Mean QRS‐­T angle was also more in cases (P < .05). T wave amplitude (TwA) in V1 more than V6 was present in 4/25 patients of CS whereas 0/25 of controls (P = .04), two of them had both the findings. Both these ECG features had specificity and positive predictive value (PPV) of 100% for CS. Upright T in V1 was more often seen among pts with CS {Gr A 14/25 vs 4/25 in Gr B} (P < .05). The clinical outcome was also worse with more composite events in CS arm over a follow up period of 6 ± 4 years (P < .0001).

Conclusion:

Widening of QRS‐­T(f) angle(QRSTA) and T wave amplitude in V1 more than V6( T v1 > v6) are useful makers for CS masquerading as IVT, even before the echocardiographic Conflict: This data has been presented earlier in a local meeting in INDIA, however NOT PUBLISHED YET.

FIGURE 1 A, CMR suggestive of CS. B, Myocardial uptake (SUV max = 11) along with avid uptake in right supraclavicular, level V cervical and para‐tracheal lymph node(LN). Biopsy was performed from supraclavicular LN

FIGURE 2 Flow chart showing inclusion of cases and controls

FIGURE 3 A, Wide QRSTA seen in a case of CS. The frontal QRSTA was 148°. B: Another case with wide QRS T angle (97°)

FIGURE 4 A, TwA in V1 more than V6 in a case from GrA. Also note the wide QRSTA in frontal plane. Another case with TwA V1>V6

FIGURE 5 A, Upright T wave in V1. Note that the QRSTA was also wide (102). Another case of CS with upright T in V1

FIGURE 6 A, ECG of a patient from Gr B, the T wave was negative in V1. The QRSTA was also narrow. B, This was an ECG of a patient from control arm. Although the T wave in V1 was positive here, the TwA in V1 was lesser than V6

AP19‐­01035

Prognostic significance of ventricular fibrillation Induced by non‐­aggressive protocol of programmed electrical stimulation in Brugada Syndrome

Tomonari Kimura, Hiroshi Morita, Saori Asada, Yoshimasa Morimoto, Masakazu Miyamoto, Koji Nakagawa, Nobuhiro Nishii, Atsuyuki Watanabe, Hiroshi Ito

Okayama University, Japan

Introduction:

Prognostic significance of programmed electrical stimulation (PES) in patients with Brugada syndrome (BrS) is controversial. One of the reasons of the different results of significance of PES will be resulted from non‐­uniform PES protocol, such as induction sites, minimum coupling interval (CpI) and number of extrastimuli, in each center. The optimal protocol of the PES for predicting prognosis has not been established in BrS.

Methods:

The subjects of this study were comprised of 211 patients with BrS who had not experienced documented ventricular fibrillation (VF) (201 males, age: 46 ± 13 years). The subjects included 125 asymptomatic patients and 86 patients with syncope. We performed PES with 2 basic cycle lengths (600 and 400 ms) and up to 3 extrastimuli at right ventricular apex (RVA) and RV outflow tract (RVOT) in each patient. Minimum CpI of extrastimuli was 180 ms. We terminated induced VF by direct cardioversion if it continued ≥15 seconds. If VF terminated spontaneously within 15 seconds, we defined it as non‐­sustained polymorphic ventricular tachycardia (NS‐­PVT). We evaluated time from initial visit to the hospital to the VF event by Cox's proportional hazards model.

Result:

PES induced VF in 97 patients (46%) with a protocol of CpI ≥ 180 ms and 46 patients (22%) with CpI ≥ 200 ms. The CpI that induced VF was 197 ± 17 ms (range: 180‐­260 ms). The number of extrastimuli that induced VF was 1 extrastimlus in 6 patients (5%), 2 extrastimuli in 55 patients (57%) and 3 extrastimuli in 36 patients (37%). Site of induced‐­VF was RVA in 24 patients (25%), RVOT in 38 patients (39%) and both in 35 patients (36%). Twenty‐­four patients (11%) experienced VF during follow‐­up. Induced VF by PES with CpI ≥ 180 ms was associated with arrhythmic events during follow‐­up (hazard ratio [HR]: 3.3, confidence interval [CI]: 1.4‐­8.5, P < .01). Induced NS‐­PVT was not associated with VF events. The risk of arrhythmic events increased if VF was induced by PES with longer CpI (unit HR of induced VF/+10 ms of CpI: 1.3, CI: 1.0‐­1.6, P = .03). Induced‐­VF by 1 or 2 extrastimuli was significantly associated with VF event (HR: 15.2 [P < .01] and 2.9 [P = .03], respectively), whereas VF induced by 3 extrastimuli did not predict VF. Induction site, effective refractory periods and HV interval did not predict VF events.

Conclusion:

The present study showed that induced VF by PES with long CI of 1 or 2 extrastimuli could predict VF in BrS patients without documented VF. Non aggressive PES protocol will be associated with occurrence of VF events.

AP19‐­01044

A new quantitative criterion for the judgement of the ablation target of idiopathic right ventricular outflow tract arrhythmias

Wenqing Zhu, Yang Pang

Zhongshan Hospital, Fudan University, Shanghai, China

Introduction:

Idiopathic ventricular arrhythmia (IVA) was one of the most common disease and mainly originated from the right ventricular outflow tract (RVOT). It presented with a left bundle branch block and inferior‐­axis morphology in ECG and can be cured effectively by radiofrequency catheter ablation (RFCA) 1‐­3. Several methods were used in the identification of an ideal ablation target including the local activation preceding time (LAPT), a QS morphology in unipolar electrogram (UEGM) and an electrical potential reversal when a PVC occurred 4‐­6. However, these methods mainly relies on the personal experiences and techniques, which leading to different success rates in different medical centers. The present study was performed to re‐­evaluate the electrophysiological characteristics of the bipolar and unipolar electrogram for both successful and failed ablation targets in order to summarize a more detailed quantitative criterion for the judgement of an ideal ablation target.

Methods:

A consecutive series of 111 patients who underwent radiofrequency catheter ablation (RFCA) for a total of 111 morphologies of RVOT premature ventricular complex (PVC) and 5 morphologies of RVOT ventricular tachycardia (VT) were studied. 91 success targets (ST) and 114 failed targets (FT) were recorded during the operation. RVOT were divided into three parts by the detailed three‐­dimensional electroanatomical voltage mapping using the CARTO system prior to the RFCA. The voltage on bipolar electrogram was defined as follows: amplitude <0.5 mV as “low‐­voltage zone,” amplitude between 0.5 and 1.5 mV as “transitional‐­voltage zone,” and amplitude >1.5 mV as “normal‐­ voltage zone.” The max slope of the descending limb (MSDL), local activation preceding time (LAPT) and the interval of MSDL (IMSDL) of the unipolar potential were then calculated and analyzed for ST and FT groups.

Result:

Successful ablation was acquired in 102 patients(102 targets) and 9 patients failed. 15 arrhythmias were classified in the low‐­voltage zone, 66 arrhythmias in the transitional‐­voltage zone, and 15 arrhythmias in the normal‐­voltage zone. There were no significant difference of the max slope of the descending limb (MSDL) between ST group and FT group. The local activation preceding time (LAPT) was higher in ST group than that in the FT group (30.0 ± 4.3 vs 22.8 ± 6.3 s, P < .001). The interval of MSDL (IMSDL) was lower in ST group than that in the FT group (9.93 ± 6.32 vs 21.7 ± 16.1 s, P < .001). IMSDL and LAPT have a predictive value for a ST(AUC 75% and 83.7%). The optimal cut off (OCO) for LAPT and IMSDL were 24.5 ms (Sensibility 95.6%, Specificity 58.8%) and 20 ms (Sensibility 95.6%, Specificity 50.9%) respectively. A better predictive value can be acquired when IMSDL and LAPT were combined used (AUC 93.9%, Sensibility/Specificity 92.3%/84.2%).

Conclusion:

A majority of RVOT VA originated from the abnormal voltage area under pulmonary valves. A better predictive value can be acquired when IMSDL and LAPT were combined used. Keywords: Ablation; Right ventricular outflow tract; Ventricular arrhythmia

AP19‐­01046

Electrocardiogram analysis and radiofrequency ablation of idiopathic premature ventricular contraction with different origins of ventricular outflow tract

Wenqing Zhu

Zhongshan Hospital, Fudan University, Shanghai, China

Introduction:

Objective: Premature ventricular contractions (PVCs) is a common arrhythmia that affects cardiac function and quality of life. The characteristics of 12‐­lead electrocardiogram (ECG) can indicate its existence and origin. In this study, we evaluate the effect of 12‐­lead ECG on the localization of PVCs before RFCA to better know the surface ECG manifestations of effective ablation in clinical. So, it can guide the clinician to fix position more preciously before RFCA and to improve the success rate of surgery.

Methods:

168 patients who had been diagnosed PVC with non‐­organic heart disease and underwent RFCA were enrolled. According to the origin of RFCA's result, the data of surface ECG of these patients were collected and analyzed to investigate the relationship between surface ECG characteristics and specific targets position in RFCA.

Result:

1. On the 12‐­lead ECG, in leads II, III and aVF, the main wave presented as R prompts the origin from the outflow tract. When the chest transitional lead <V3 and TR/TQRS ≥ 0.5, the possibility origin of left ventricular outflow tract (LVOT) is high, and the overall positive predictive value and negative predictive value are above 90%. 2. Idiopathic PVCs originated in the right ventricular outflow tract (RVOT), when the I lead shows the negative wave (rs,qs,qr) ,we can guess it may originate from septum(Sep), moreover, when the I lead shows the positive wave (R,r,rsr’) ,it may originate from free wall(FW) (P < .05); R waves descending of FW have notch in inferior leads II、III and aVF (95.5% vs 27.8%, P < .01), in addition, the chest transitional lead of FW is always late ,generally after V3 lead (17 vs 24, P < .01). Among the septum PVCs, if RII>RIII, QSaVR>QsaVL, it is more likely originated from posterior septum (PS), on the contrary, it may originate from anterior septum (AS) (67.6% vs 33.3%, P = .002; 79.4% vs 25.6, P < .01). 3, The I lead shows rs or rS types when PVCs from the left coronary cusp (LCC) and the junction of left‐­right coronary cusp(L‐­RCC), PVCs from the right coronary cusp(RCC) show the positive R, r, rsr’ types and they 100.0% show RII>RIII, QSaVR>QSaVL, with a sensitivity of 100.0%, a specificity of 79.6%, a positive predictive value of 57.1% and a negative predictive value of 100.0%. However, in other two groups, RIII>RII, QSaVL>QSaVR (all P < .01) always can be seen. In the inferior wall leads, majority of PVCs from L‐­RCC have “notching” on the R wave descending (90%), however there's no “notching” on R wave descending in the inferior wall leads of PVCs originated from LCC and RCC.

Conclusion:

RFCA is safe, effective and successful in the treatment of PVCs originating from outflow tract. The correlation between ECG characteristics and the origin of PVCs is closely, it can help the clinician to fix the specific origin about PVCs and to provide the basis for searching precisely targets in the operation rapidly.

AP19‐­01053

Effect of contact force at the tip of ablation catheter on the ablation lesion size of right ventricular outflow tract of pigs

Guoqiang Zhong, Jingbo Jiang

The First Affiliated Hospital of Guangxi Medical University, China

Introduction:

To evaluate the impact of contact force on the lesion formation during radiofrequency catheter ablation (RFCA) in the right ventricular outflow tract (RVOT) of pig, and to explore the safe and effective contact force range of RFCA of ventricular arrhythmia originated from RVOT

Methods:

ThermoCool Smart Touch contact sensing ablation catheter was introduced into RVOT via the femoral vein under the guidance of CARTO 3 system. Three to four points were choosed in the free wall and same in the septum of RVOT, four different contact force levels (3‐­9, 10‐­19, 20‐­29, and 30‐­39 g) were applied in order at each point. The local ventricular voltage and impedance measured using different contact force levels were recorded and compared. We randomly divided the Bama pigs (weighing 40‐­50 kg) into four groups (3 pigs in each group) according to different contact force levels: Group A (3‐­9 g), Group B (10‐­19 g), Group C (20‐­29 g) and Group D (30‐­39 g). In each group, RFCA were performed at three points in the free wall and septum of RVOT, respectively. RFCA parameters were kept constantly during ablation discharge and set as follows: power control mode, radiofrequency power 30 W, saline irrigation rate 17 mL/min, and duration of ablation discharge 30 seconds. The thoracotomies were performed after operation, the maximum depth, surface diameter and lesion volume were measured and recorded, the relationship between contact force and lesion size was evaluated.

Result:

The maximum depth, surface diameter and volume of lesions in RVOT correlated well with contact force when the radiofrequency power, time and irrigation rate remained constant. When the septum was ablated, the volume, maximum depth, and surface diameter of the ablation lesion in the four groups A, B, C, and D were positively correlated with the contact force. However, when the free wall was ablated, the volume, maximum depth, and surface diameter of the ablation lesion in the groups A, B and C were positively correlated increasingly with the contact force. However the maximum depth and volume of lesions in group D were similar to group C. Regional ventricular bipolar voltage, unipolar voltage, and impedance were weakly positively associated with contact force (P < .001). The transmural lesions were found when contact force exceeded 10 g at the free wall, while lesions at septum were non‐­transmural even when the contact force attained 30 g.

Conclusion:

The lesion size in RVOT correlated well with contact force between the distal end of ablation catheter and myocardial tissue when the radiofrequency power, time, and irrigation rate remained constant. Keeping the contact force in the range of 3‐­20 g may be effective and safe.

Keywords: Right ventricular outflow tract, Ventricular arrhythmias, Contact force, Catheter ablation, Efficacy

AP19‐­01054

Epicardial ablation of refractory ventricular tachycardia in a young athletic man diagnosed with arrhythmogenic right ventricular cardiomyopathy and Kommerell's diverticulum: A rare case

Ahliah Ibrahim, Abigail Louise Te‐Rosano, Douglas Bailon, Fa‐Po Chung, Clara Tolentino

Philippine Heart Rhythm Society, Philippines

Introduction:

We present the case of a 31‐­year‐­old athletic man who had repeated emergency department visits due to palpitations and dizziness. ECG showed wide complex ventricular tachycardia (VT) with left bundle branch block pattern with inferior axis. After pharmacologic cardioversion, there was T wave inversion in V1‐­V4 with prominent epsilon wave in V1. Cardiac magnetic resonance imaging revealed that the right ventricle is dilated with depressed systolic function, and small, dyskinetic aneurysms with delayed hyperenhancement of the apex. The left ventricle is normal‐­sized with normal resting systolic function. There is also an incidental finding of a right‐­sided aortic arch with Kommerell's diverticulum. Based on the revised Task Force criteria, above findings are suggestive of arrhythmogenic right ventricular cardiomyopathy (ARVC) but his genetic testing only 50 to 60% attribute to ARVC. He underwent implantation of a dual chamber intracardiac cardioverter‐­defibrillator (ICD) and on maximum anti‐­arrhythmic agents. Due to persistent VT and frequent ICD shocks, epicardial radiofrequency ablation (RFA) was contemplated. Endocardium showed normal voltage despite MRI findings. Sinus rhythm voltage map showed low voltage area of the entire RV epicardium while endocardial sinus rhythm voltage map demonstrated normal voltage. Sinus rhythm activation map showed two regions of latent activation consistent of the entrance and exit site areas shown in the VT activation map. During VT, mid‐­diastolic potential were noted in the protected isthmus which was intramyocardial in location. VT was successfully terminated within 5 seconds of radiofrequency application in this area.

Methods:

n/a

Result:

n/a

Conclusion:

ARVC is a progressive disease characterized by fibrofatty replacement of the myocardium with high predisposition to ventricular tachycardia (VT) and sudden cardiac death (SCD). To date, there has been no published literature describing the coincidence of ARVC and Kommerell's diverticulum. Also, our case disputes the existing knowledge of having abnormal endocardial voltage map congruent with the MRI findings in ARVC, which has lead us to an epicardial‐­only VT ablation. These data justify the need to report our case. Long term follow‐­up of our patient is warranted to provide possible missing data on arrhythmic risk in these group of patients.

AP19‐­01074

Pleomorphic ventricular tachycardia in structurally normal heart

Gautam Singal, Vikas Kataria, Amitabh Yaduvanshi, Vipul Malpani, Pritam Kittey, Mohan Nair

Holy Family Hospital, India

Introduction:

Pleomorphism as defined by multiple ventricular tachycardia morphologies is usually associated with either coronary artery disease or structural heart disease. We present an unusual case of pleomorphic VT with differing morphologies.

Methods:

Fifty year old gentleman presented with recurrent palpitations. ECG showed fast broad irregular tachycardia with differing morphologies (Figure 1). He had undergone DC cardioversion twice at another hospital. ECG during sinus rhythm did not show pre‐­excitation, long QT or any other abnormality (Figure 2).

Result:

Echocardiography showed normal bi‐­ventricular structure and function. He was taken up for EP study which showed clear VA dissociation during the tachycardia (Figure 3). Further evaluation coronary angiogram, contrast enhanced CT scan of the chest and cardiac MRI showed no abnormality.

Conclusion:

Fast, broad tachycardia is typically seen in patients with coronary heart disease or with underlying structural abnormality. This type of tachycardia is extremely rare in structurally normal heart.

FIGURE 1 12 lead ECG shows fast broad irregular tachycardia with differing morphologies

FIGURE 2 12 lead ECG during sinus rhythm does not show pre‐­excitation, long QT or any other abnormality

FIGURE 3 EGMs recorded from high right atrium during tachycardia shows VA dissociation.

AP19‐­01082

Predictors of poor response to immunosuppressive therapy for cardiac sarcoidosis

Nalla Swapna, Muthiah Subramanian, Sahifa Tarannum, Mohd Mansoor Mohiuddin, Daljeet Saggu, Sachin Yalagudri, Jugal Kishore, Calambur Narasimhan

Care Hospital, India

Introduction:

Immunosuppressive therapy with steroids has become the cornerstone of treatment of cardiac sarcoidosis (CS). There is limited data on the factors affecting the clinical response to therapy. The objectives of this study were to evaluate the response to immunosuppressive therapy in CS and identify predictors of poor response.

Methods:

Data of 90 consecutive patients with CS from the Granulomatous Myocarditis Registry was analyzed. Data regarding clinical presentation, co‐­morbidities, baseline electrocardiogram, echocardiogram, and 18‐­Fluorodeoxyglucose (FDG) PET‐­CT were extracted from the registry database. All patients were treated with a standard treatment regimen of corticosteroids and methotrexate. Response to therapy was assessed 3‐­6 months after initiation of immunosuppression. Clinical response (CR) was defined as a reduction in NYHA Class >1 and/or freedom from ventricular arrhythmias and heart failure hospitalizations. Disease activity response (DAR) was defined as either a repeat FDG PET showing complete resolution of myocardial uptake or improvement in left ventricular Ejection Fraction(LV EF) >10% (in patients with a reduced EF at therapy initiation). Complete responders fulfilled both CR and DAR criteria. Partial responders had either CR or DAR and non‐­responders had neither CR or DAR.

Result:

Among the 90 patients receiving immunosuppression, 35 (38.9%) were complete responders, 25 (27.8%) were partial responders, and 30 (33.3%) were non‐­responders. Univariate analysis comparing complete responders and non‐­responders revealed that a lower LV EF (49.4 + 13.7 vs 39.6 + 14.9, P = .002) and reduced myocardial maximum standardized uptake value (SUV) on 18‐­FDG PET (7.9 + 4.8 vs 5.3 + 4.0, P = .022) were predictors of non‐­response. When comparing all responders (complete and partial) and non‐­responders, the same parameters were found to be significant. Logistic regression identified two independent predictors of non‐­response to immunosuppression: LV EF < 40% (HR 1.61, 95% 1.06‐­7.69, P = .012) and maximum SUV < 5.5 (HR 1.28, 95% CI 1.05‐­6.12, P = .005). The final prediction model had a good discriminatory power (Area under the curve 0.82).

Conclusion:

A reduced LV EF and lower myocardial uptake on 18‐­FDG PET are independent predictors of poor response to immunosuppression in patients with CS.

AP19‐­01100

Unusual reversible etiology of ventricular tachycardia

Praloy Chakraborty, H. Isser, Sudheer Arava, Karan Madan

VMMC and Safdarjung Hospital New Delhi, India

Introduction:

We report a case of VT due to myocardial tuberculosis with structurally normal heart in echocardiography and without any systemic symptom of tuberculosis. We also documented regression of pathology with anti‐­tubercular therapy.

Methods:

A 25‐­year‐­old young male presented without any back ground history of fever or constitutional symptoms, presented with recurrent symptomatic monomorphic Ventricular tachycardia of right bundle branch block morphology (Figure 1A). Baseline ECG documented T wave inversion in precordial leads (Figure 1B). Echocardiography was Normal (Figure 1C). FDG‐­PET study showed perfusion defect with good FDG uptake in apex and apico‐­anterior segments of left ventricle and multiple FDG avid discrete and coalescent mediastinal and abdominal lymph nodes (Figure 1D). Routine blood investigations were normal except ESR of 30. Tuberculin skin test showed induration of 30 × 25 mm after 48 hours. Endobronchial Ultrasound Guided Transbronchial Needle Aspiration smear from mediastinal node showed well‐­formed epithelioid cell granuloma (arrow) and areas of necrosis (stars) (Figure 1E).

Result:

Patient was treated with anti‐­tubercular agent (3 months of 4 drugs and 6 months of 2 drugs). Repeat FDG‐­PET after 3 months of treatment showed near complete resolution of abdominal and thoracic lymphadenopathy (Figure 1F). On Follow‐­up after initiation of therapy and for 1 year after completion of therapy patient was asymptomatic. 24 hours Holter at 6 months and 1 year after therapy showed no sustained or non‐­sustained ventricular arrhythmia.

Conclusion:

Life threatening ventricular arrhythmia due to tuberculosis of heart can be completely cured with anti‐­tubercular therapy.

AP19‐­01117

Big endothelin‐­1 as a clinical marker for ventricular tachyarrhythmias in post‐­infarction left ventricular aneurysm patients

Xiaohui Ning, Zihe Yang, Xuerui Ye, Yanhua Si, Fang Wang, Shu Zhang

State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular D, China

Introduction:

Ventricular tachyarrhythmia is the leading cause of death in post‐­infarction patients. Big endothelin‐­1 (ET‐­1) is a potent vasoconstrictor peptide and plays a role in ventricular tachyarrhythmia development. The aim of this study was to investigate the association between big ET‐­1 concentrations and prevalent ventricular tachyarrhythmia in post‐­infarction left ventricular aneurysm (PI‐­LVA) patients.

Methods:

A total of 222 consecutive PI‐­LVA patients who received medical therapy were enrolled. There were 43 (19%) patients who had ventricular tachycardia/ventricular fibrillation (VT/VF) at admission. The clinical characteristics were collected, and the plasma big ET‐­1 level was measured. Associations between big ET‐­1 and the presence of VT/VF were assessed. Patients were followed up for outcomes including cardiovascular mortality, VT/VF attack and all‐­cause mortality.

Result:

The median concentration of big ET‐­1 was 0.635 pg/mL. Patients with big ET‐­1 concentrations above the median were more likely to have higher‐­risk clinical features. There was a positive correlation of the big ET‐­1 level with VT/VF (r = .354, P < .001). In the multivariate logistic regression analysis, big ET‐­1 (OR = 4.06, 95% CI 1.77–9.28, P < .001) appeared as an independent predictive factor of the presence of VT/VF. Multivariate Cox regression analysis suggested that big ET‐­1 concentration was independently predictive of VT/VF attack (OR = 2.5, 95% CI 1.4–4.5, P < .001). NT‐­proBNP and LVEF ≤ 35% were demonstrated to be independently predictive of cardiovascular mortality and all‐­cause mortality.

Conclusion:

Increased big ET‐­1 concentration in PI‐­LVA patients was a valuable independent predictor for the presence of ventricular tachyarrhythmia and VT/VF attack during follow‐­up.

AP19‐­01124

Efficacy and safety of catheter ablation using a remote magnetic navigation system for the treatment of electrical storm in patients with organic heart disease

Hiroyuki Fujii, Katsunori Okajima, Yuichi Nagamatsu, Tomoyuki Nakanishi, Yoshio Onishi

Kakogawa Central City Hospital, Japan

Introduction:

Remote magnetic navigation systems (MNS) have been available as a tool for catheter ablation (CA) in recent years. However, the efficacy and safety of CA for the treatment of electrical storm (ES) in patients with organic heart disease (OHD) using MNS have not been reported in detail. The aim of this study was to evaluate the clinical outcomes of CA using MNS and CARTO system for ES associated with OHD.

Methods:

Between July 2016 and June 2019, we retrospectively enrolled consecutive seven patients (Median 73 (30‐­78) years, seven males, LVEF 30 (27‐­48) %) including severe ischemic heart disease (IHD, n = 3), idiopathic non‐­ischemic dilated cardiomyopathy (DCM, n = 3) and arrhythmogenic right ventricular cardiomyopathy (ARVC, n = 1) underwent CA for ES using an MNS. Radiofrequency energy (30‐­50 W) was delivered in the critical regions judged by substrate mapping during sinus rhythm for poorly tolerated ventricular tachycardia (VT) and activation map during tolerable VT. All patients received implantable cardioverter‐­defibrillators (ICDs) either before or after ablation. Clinical outcome after CA was evaluated during a follow‐­up period of 23 (1‐­33) months.

Result:

All patients underwent ventricular endocardial ablation at the 1st CA session. Clinical VTs were induced in three of seven (43%) patients and could be successfully suppressed by CA. Clinical VTs could not be induced during the ablation procedure in other four patients, and they were performed substrate ablation. After the 1st session, three patients experienced ES recurrence with ICD shocks. Two of these patients underwent repeat CA using MNS including both left ventricular epicardial and endocardial ablation, and they were free from any VT recurrence. In the remaining one ARVC patient with ES, VT storm could be managed by atrial overdrive pacing using ICD and amiodarone. After the last CA (median 1 (1‐­4) times), six of seven patients were free from ES and ICD shocks, and all patients were alive. The total procedure time and fluoroscopy time were 248 (200‐­360) minutes and 13 (9‐­27) minutes, respectively. No major complication occurred during the ablation procedure.

Conclusion:

Catheter ablation using MNS may be safely performed with good clinical outcomes in patients with electrical storm and organic heart disease.

AP19‐­01138

Electrical storms of Brugada Syndrome patients were successfully ablated by ablation: 3 case report from Hanoi Vietnam

Tuan Nguyên Xuan

Hanoi Heart Hospital, Vietnam

Introduction:

Not uncommonly, Brugada syndrome (BrS) is associated with electrical/VF storms that could result in death and even in patients who have an ICDs whose battery are rapidly drained. Psychological trauma from incessant shocks are common and often the patients wish to die than continue to suffer from ICD shocks. Isoproterenol or quinidine, while effective in some patients, are often ineffective in some and not available in many countries like Vietnam causing management crisis. We report 3 such ES patients who were effectively treated with catheter ablation.

Methods:

3 BrS patients who were males (P1 , P2, P3) and are 57, 59 and 66 years old respectively. ECG pattern: P1 & P2 had spontaneous type I Brugada ECG pattern but P3 had ajmaline provoked type 1 Brugada ECG. P1 & P2 had also Early Repolarization pattern on the inferior leads Clinical feature: P1 max 5 shocks per year on amiodarone 200 mg/d, P2 max 150 shocks 1 days total 400 shocks on 2 ICD on amiodarone 200 mg per day, P3: 152 shocks on ICD1 and 59 shocks on ICD 2 with quinine (antimalaria); Procedure RF epicardial ablation: P1 required 2 ablations: January 2106 at the anterior RVOT substrates and the second time May 2016 Inferior epicardial substrates, P2 January 2017 and P3 June 2019. Ablation end Points: elimination all late potentials (LP) Follow up: clinical symptoms, ECG, Echocardiography, ICD check every 1 or 3 months. All 3 patients were done pro bono at Bumrungrad International Hospital, Bangkok Thailand.

Result:

All 3 cases became VF free and no recurrent ICD discharge, Brugada ECG has been normalized. Echocardiography is normal.

Conclusion:

Epicardial ablation in BrS and combined syndrome of BrS and Early Repolarization with Electric Storm are effectiveness in preventing recurrent VF episodes, improves quality of life, reduces healthcare expenses due to extended battery life of ICD.

AP19‐­01142

Unusual location of a ventricular tachycardia: Let the cat out of the bag

Pradeep Wijayagoonawardana, Clare Stodart, Nicola Viola, Arthur Yue

University Hospital Southampton NHS Foundation Trust, United Kingdom

Introduction:

A 49‐­year‐­old female with Ebstein's anomaly underwent an ablation of ventricular tachycardia (VT). She had undergone an atrial septal defect repair and tricuspid valve (TV) replacement (bioprosthetic) 15 years ago and later had an ICD implanted for recurrent ventricular tachycardia.

Methods:

At the procedure, a hemodynamically stable monomorphic VT with left bundle branch block pattern was easily induced. An electroanatomic map of the right ventricle (RV) during VT was created and based on activation and entrainment, the VT circuit appeared to be located on the RV antero‐­lateral free wall. A series of substrate ablation lesions did not affect the inducibility of VT. Poor endocardial pacemapping morphology match raised the suspicion of an RV epicardial site. On further mapping, the ablation catheter traversed outside the TV ring into a space anterior to the RV cavity with ventricular signals. The distinct pouch ‐­like space was located anterolateral to the site where the signals were best within the RV cavity. Electrograms were 210 ms ahead of surface ECG and the earliest site showed concealed entrainment. A single RF lesion terminated VT within 2 seconds and a consolidation lesion was added in view a late potential in the same location. VT was not inducible thereafter.

FIGURE 1 Top Left: Concealed entrainment with a post pacing interval of 30 ms (450‐420 = 30 ms). Top Right: Electroanatomical map showing pouch like space and failed lesions (A) and successful lesion (B). Bottom Left: Sizing balloon via the channel opening during diagnostic catheterization. Bottom Right: Intra‐operative photo showing the channel with a probe ( ) in it (the valve has been excised out). TA: Tricuspid annulus, RV: Right ventricle

Result:

She did well – free of VT but deteriorated of severe right heart failure. Echocardiography showed significant tricuspid regurgitation and at diagnostic right heart catheterization, a guidewire was passed through the paravalvular channel. A sizing balloon established that it was not a true paravalvular leak, but a distinct space as seen during 3D mapping. Subsequently during surgery, a large opening was seen at the atrial aspect, lateral to the TV annulus which extended distally to the RV cavity. The substrate of the tachycardia was likely related to localized fibrosis caused by the distal suture within the pouch.

Conclusion:

Ebstein's anomaly is a rare congenital malformation of the tricuspid valve leaflets which leads to apical displacement of the functional annulus leading to atrialization of the proximal (inlet) right ventricle. Surgical correction becomes necessary when there is right heart failure and the goal is to establish a functional valve at the correct plane with some form of volume reduction in the “restored” right ventricle to correct geometry – which is by plication. The findings at the ablation and surgery suggested that she had a longitudinal plication which had dehisced at its atrial and ventricular ends. Ventricular tachycardia is a known sequelae of the disease itself and of the operation. As far as we know, this is the first case of a VT substrate localized within the plication pouch. In the operated heart, a surgical scar is the most likely etiology and, in our patient, a scar within the plication pouch led to the tachycardia.

AP19‐­01154

Defining the substrate for ventricular tachycardia in ischemic vs non‐­ischemic cardiomyopathy

Chrishan Nalliah, Ivana Trivic, Timothy Campbell, Saurabh Kumar

Royal Melbourne Hospital, Australia

Introduction:

Catheter ablation has emerged as an effective tool for management of ventricular tachycardia (VT) in structural heart disease amongst patients with ischemic (ICM) and non‐­ischemic cardiomyopathy (NICM). ICM and NICM comprise vastly different characteristics, largely informed by the underlying electrophysiologic substrate. However, data describing these differences are sparse.

Methods:

We prospectively recruited 37 consecutive patients (ICM 51%, NICM 49%, age 66 ± 12 years, male 82%) having catheter ablation with scar‐­related re‐­entrant VT with pre‐­dominant left ventricular (LV) involvement. All patients underwent high density voltage mapping of the LV prior to ablation. Off‐­line analysis was performed to determine LV low voltage and scar areas based on bipolar (low voltage <1.5 mV, scar <0.5 mV) and unipolar (low voltage <8.3 mV, scar <3 mV) criteria. Additionally, proportion of late potentials (LP), fractionated points, VT cycle length (CL) (clinical and procedural) and stimulation‐­QRS (stim‐­QRS) delays were recorded. Device interrogation and clinical follow up data were used to determine rates of recurrent VT following ablation.

Result:

ICM was associated with a larger low voltage (bipolar 25 ± 7% vs 15 ± 5%, P < .001 and unipolar 36 ± 18% vs 26 ± 21%, P < .001) and scar areas (bipolar 21 ± 9% vs 7 ± 8%, P < .001 and unipolar 24 ± 14% vs 11 ± 8%, P < .001) compared with NICM. However, the proportionate increase in scar between bipolar and unipolar voltage was greater among NICM vs ICM patients (85 ± 100% vs 20 ± 77%, P = .03). Larger scar areas in ICM was paralleled by higher proportion of complex electrograms (19 ± 11% vs 9 ± 9%, P = .003). Furthermore, ICM associated with longer VT CL (max/mean clinical 395 ± 61 vs 331 ± 62 ms, P = .005/378 ± 66 vs 322 ± 54 ms, P = .01 and max/mean procedural 403 ± 80 vs 344 ± 75 ms, P = .04/358 ± 77 vs 313 ± 52 ms, P = .05) and greater stim‐­QRS delays (max/mean 91 ± 51 vs 42 ± 17 ms, P = .002/77 ± 40 vs 33 ± 9 ms, P < .001). VT storm was also more highly prevalent in ICM vs NICM (53% vs 6%, P = .002). Following catheter ablation, 57% had VT recurrence after a single procedure, and 24% after multiple procedures. Single (37% vs 50%, P = .49) and multi‐­procedure (16% vs 33%, P = .20) recurrence rates were similar between groups.

Conclusion:

The VT substrate in ICM vs NICM is characterized by slower VT, larger regions of low voltage/scar, greater proportion of complex points and longer stim‐­QRS delays. These data imply that the electrophysiologic VT substrate are different in ICM vs NICM. However, rates of VT recurrence are similar between groups.

AP19‐­01184

Acute coronary syndrome presented with ventricular fibrillation: how aggressive emergency PCI should be done? (case report)

Jeremiah Suwandi, Bertha Bertha, Nixie Elvaretta Liono, Audrey Hadisurya, Sabrina Agatha Jean Aswan, Wendy Wiharja

Universitas Pelita Harapan, Indonesia

Introduction:

Underlying causes of cardiac arrest are Acute Coronary Syndrome (ACS) 67%, cardiomyopathy 13%, valvular heart disease 10%, and others 10% (Deshpande S, et al). 30‐­day mortality with resuscitated arrest in STEMI 40%‐­50%. This case report aims to show how important emergency Percutaneous Intervention (PCI) in such manner.

Methods:

A 47‐­year old female presented with cardiac arrest. One hour prior of the arrest, the patient experienced a chest pain. ECG monitoring showed ventricular fibrillation (VF). Defibrillation was done three times and CPR was done for 15 minutes, then ROSC. The patient denied any prior illness and no family history of cardiac disease. Vital signs BP 101/72 mm Hg, HR 98 bpm, R 21 x/min. The patient underwent a emergency PCI. CT angiography showed total occlusion on proximal LAD. Result of emergency PCI and stenting showed TIMI 3 flow and minimal stenosis residual on LAD. 6‐­day follow up no chest pain, stable hemodynamics, ECG was normal

Result:

Emergency PCI is needed to decrease mechanical burden in ACS by increasing the supply of coronary vessels. By achieving this condition, the reentry impulse that may cause tachyarrhythmia can be prevented and lowering the mortality. In study by Strote, et al about evidence for early transfer of cardiac arrest patient to cath lab, there were 240 patients (61 patients admitted <6 hours: 44 were discharged alive; 179 patients admitted >6 hours: 87 were discharged alive, P‐­value .001). LOS of <6 hours group was 9.1 ± 6 days, >6 hours group was 9.8 ± 21.7 days. Mean 1‐­year survival rate in cardiac arrest patient underwent emergency PCI is 90.6% and 5‐­year survival rate is 76,5% (Dumas F, et al).

Conclusion:

There is no guideline about how aggressive emergency PCI in cardiac arrest should be done, but several studies show that the faster it is done after ROSC, the better the outcome.

Keywords: STEMI, Ventricular Fibrillation, cardiac arrest, PCI, emergency

AP19‐­01190

Is arrhythmia influencing percutaneous coronary intervention strategy in ST segment elevation myocardial infarct with onset more than 12 hours? (a case report)

Bertha Bertha, Jeremiah Suwandi, Audrey Hadisurya, Sabrina Aswan, Nixie Liono, Wendy Wiharja

Universitas Pelita Harapan, Indonesia

Introduction:

There is general agreement that reperfusion therapy should be considered if there is clinical and/or Electrocardiographic (ECG) evidence of ongoing ischemia in patient ST‐­segment elevation myocardial infarction (STEMI). Even if, according to the patient, symptoms started 12 hours before as the exact onset of symptoms is often unclear, or when the pain and ECG changes have been stuttering.1

Methods:

CASE REPORT A 39 years old male presented with chest pain for 2 days before admission. Patient had history of uncontrolled hypertension and smoking habit for 20 years. ECG on arrival showed Ventricular Tachycardia (VT), patient underwent cardioversion. Following ECG 12‐­Lead after cardioversion shown QS wave in lead II, III, AVF. Coronary angiography was performed and showed 99% stenosis in Right Coronary Artery (RCA). Percutaneous Coronary Intervention (PCI) was done in RCA.

Result:

There is, however, no consensus as to whether PCI is also beneficial in patients presenting >12 hours from symptom onset in the absence of clinical and/or electrocardiographic evidence of ongoing ischemia. In such asymptomatic late‐­comers, a small (n = 347) randomized study has shown myocardial salvage and improved 4‐­year survival resulting from primary PCI, compared with conservative treatment alone, in patients without persistent symptoms 12‐­48 hours after symptom onset. 2‐­4 The patient in this case came with unstable VT, cardioversion was performed as initial management. Ongoing ischemia findings in this patient were VT and persistent chest pain. Even though the onset of the symptoms were >12 hours, PPCI rather than pharmacological only therapy was chosen as the preferred modality.

Conclusion:

Onset of symptom <12 hours is commonly used as major indication for revascularization, but the essence of this case is that onset >12 hours with ongoing ischemia which are characterized by ECG findings (in which one of them is VT), and clinical symptoms such as angina which persist, are also indication for PCI.

AP19‐­01206

Catheter ablation to a patient of idiopathic ventricular fibrillation targeted the initiating premature ventricular complex

Hirotaka Murase, Tomoki Kubota, Shinji Yasuda, Shinsuke Ojio, Kazuhiko Nishigaki, Shinya Minatoguchi

GIFU Municipal Hospital, Japan

Introduction:

A 47‐­year‐­old‐­woman fell unconscious in the elementary school classroom. Her colleague provided cardiopulmonary resuscitation and called an ambulance. After the ambulance arrived, ventricular fibrillation (VF) was detected on an automatic external defibrillator (AED). VF was terminated with twice electrical cardioversions.

Methods:

She was taken to our hospital by an ambulance. A surface ECG showed frequent premature ventricular complexes (PVCs) of right ventricular outflow tract (RVOT) origin. There were no abnormal findings producing unconsciousness in brain and chest CT. She underwent a coronary angiography, but there was no significant coronary stenosis. Left ventriculography showed a regional hypokinesis of left ventricular wall due to electrical cardioversions and ejection fraction was calculated at 0.58. After she received therapeutic hypothermia, she was recovered including higher cerebral function. Twelve days after admission, she received ICD. Frequent PVCs and non‐­sustained VTs were observed on remote monitoring system, but sustained arrhythmia was not observed. Approximately 6 months after discharged our hospital, we noted VF episode that self‐­terminated. These ventricular arrhythmias were medically refractory, so catheter ablation targeted the initiating PVC was performed approximately 15 months after documented VF episode. Because PVCs seemed to be origination from RVOT, Multielectrode array was inserted into right femoral vein and deployed in the RVOT as guided by fluoroscopy. The 3D geometry of RVOT was constructed by navigating the mapping and ablation catheter within the RVOT using the non‐­contact electroanatomic mapping system. Spontaneous PVC that originating from postero‐­septal site in RVOT was recorded. At early activation site, pacemapping was performed and it seemed perfect matching on the 12‐­lead ECG. Ablation was performed by delivering radiofrequency energy with the ablation catheter in temperature‐­control mode.

Result:

Because the PVC was eliminated during the ablation and became non‐­inducibility with programmed electrical stimulation with isoprenaline infusion, the ablation procedure was considered successful.

Conclusion:

After successful ablation, sustained and no‐­sustained arrhythmia were not observed and little PVCs were documented on remote monitoring system.

AP19‐­01209

Prediction of distribution of late potentials for ventricular tachycardia ablation with Tc‐­99 m scintigram scar

Kentaro Ozu, Hitoshi Minamiguchi, Tomoaki Nakano, Akihiro Sunaga, Isamu Mizote, Hiroya Mizuno, Shungo Hikoso, Yasushi Sakata

Department of Cardiovascular Medicine Osaka University Graduate School, Japan

Introduction:

Substrate mapping is the important strategy of the radiofrequency ablation for ventricular tachycardia (VT). Late potential (LP) is one of the VT substrate which indicates the isthmus of VT in the low voltage area. Efficacy of enhanced MRI or CT for prediction of the VT substrate was reported. On the other hands, according to the prior report, Tc‐­99 m scintigram could determinate the viability of ventricular myocardium and could discriminated the low viability area. In this study, we evaluated that we could predict the distribution of LPs with Tc‐­99 m scintigram. Moreover, we evaluated the characteristics of the area where LPs existed.

Methods:

In seven patients (age, 66.7 ± 8.9 years; 7 male; left ventricular (LV) ejection fraction, 25.5 ± 9.2%; LV volume, 275 ± 105 ml) with ischemic cardiomyopathy and VT, LV electroanatomical map (EAM) and Tc‐­99 m scintigram were obtained and were divided into twenty segments. LPs were determined as continuous fragmented activities or isolated potentials after the QRS and were evaluated in EAM. The relation between LPs and scintigrafic characteristics were evaluated in total of 140 segments (Figure A).

Result:

LPs were recorded in 51 segments. According to the Tc‐­99 m uptake rate, cut off value 34% was set for the prediction of the distribution of LPs with ROC curve (FigureB). LPs were observed in the lower scintigram perfusion segments with ≤34% uptake rate (n = 51) more than the segments with >34% uptake rate (n = 89) with statistical significance (76.4% vs 13.4% P < .0001). Especially, in lower scintigram perfusion segments with ≤ 34% uptake rate (n = 51), the mean uptake rate of LPs recorded segments was significantly lower than LPs non‐­recorded area (20.8% vs 28.2% P = .0012). Moreover, enhanced cardiac CT was performed in three patients before ablation. The merged 3D images with CT and Tc‐­99 m Scintigram were available. Figure C showed the well coexistence between LP recorded area and low viability area with ≤34% uptake area

Conclusion:

Lower perfusion area of Tc‐­99 m scintigram could be utilized to predict VT substrate location in ICM patients and make the mapping procedure more simple.

AP19‐­01216

Clinical and electrophysiologic characteristics of ventricular arrhythmia arising from pulmonary cusps

Vickram Vignesh R, Sachin Yalagudri, Daljeet Kaur Saggu, Soumen Devidutta, Prabhakar N Reddy, Sridevi Chennapragada, Narasimhan Calambur

Care Hospital, India

Introduction:

Ventricular arrhythmias (VA) have been successfully ablated from above the pulmonary cusps establishing pulmonary artery (PA) as a distinct site for the origin of VA apart from the right ventricular outflow tract (RVOT). The aim of the present study was to determine the clinical presentation, electrocardiographic and ablation characteristics of PA VAs.

Methods:

Forty five consecutive patients with LBBB and inferior axis VA were included in this retrospective study. Three‐­dimensional electromagnetic mapping was performed in all patients. Initially mapping was performed in RVOT, and later in the PA. Mapping was performed in PA if there was no early activation and/or pace mapping was unsatisfactory or initial RF lesions in RVOT was unsuccessful. All PA VAs were mapped and ablated by looping the catheter in the reversed U fashion.

Result:

The sites of successful ablation were RVOT in 22, PA in 8 patients and rest in left ventricular outflow tract (LVOT). The origin of PA VA according to cuspal positions are anterior in 4 (50%), left in 3 (37.5%), and right in 1 (12.5%). Age of onset of arrhythmia in PA VAs was significantly lower compared to RVOT VAs (39.25 ± 10.16 vs 51.82 ± 11.07 years, P < .01). Both RVOT and PA VAs were common in females (75% vs 59.1%). The symptoms and VA burden were similar in both groups. Majority of the PA‐­VA group had VT as the presenting arrhythmia (62.5 %) whereas RVOT VAs more commonly presented as premature ventricular contractions (68.18 %). The comparison of ECG characteristics are described in table 1. Mapping by reversed U method of PAVAs revealed early activation time (28.75 ± 9.39 vs 12.00 ± 8.61 ms, P < .01) compared to RVOT VAs. Pre‐­potential was present in 4 (50%) and it preceded unipolar signals 35 ± 8.33 ms compared to 23 ± 8.3 ms to bipolar signals (P < .01) (Image–I). Pace map score in PA VAs was higher than the pace map scores in RVOT (21.37 vs 14.25, P < .01).

Conclusion:

PA VAs are important subset of VAs originating from the outflow tract. PA VAs have a wider baseline QRS duration. Mapping utilizing the reversed U method helps in localization and successful ablation of PA VAs.

Table 1 Comparison of ECG characteristics of PA VA and RVOT VA

PA VA	RVOT VA	P‐­Value
QRS duration, ms	155 + 14.14	142.40 + 8.12	<0.01
Lead I (Positive) n(%)	5 ( 62.5)	4 (18.18)	0.02
R wave amplitude in LEAD II, mV	1.28 + 0.70	2.04 + 0.47	0.06
R wave amplitude in LEAD III, mV	1.32 + 0.72	1.9 + 0.57	0.15
Q wave amplitude in LEAD aVR, mV	7.2 + 5.41	8.4 + 2.6	0.66
Q wave amplitude in LEAD aVL, mV	0.83 + 0.58	0.9 + 0.31	0.83
R wave amplitude in LEAD aVF, mV	1.3 + 0.69	1.64 + 0.61	0.38
Q wave amplitude ratio aVL/aVR	0.12 + 0.06	0.11 + 0.03	0.65
R wave amplitude ratio LEAD III/II	1.03 + 0.21	0.92 + 0.07	0.31
Notches II, III, aVF n(%)	2(25)	0	0

FIGURE 1 3D activation mapping of pulmonary artery with CUSPS with unipolar and bipolar images from earliest activation point in CUSP region

AP19‐­01221

Narrow‐­complex presentation of ventricular tachycardia

Filipus Michael Yofrido, Eka Prasetya Budi Mulia, Achmad Lefi

Faculty of Medicine, Airlangga University, Surabaya, Indonesia, Indonesia

Introduction:

Tachyarrhythmia is common in emergency or intensive care unit which occurring in 12%‐­20% of all patients. 1 It is often difficult to differentiate the origin of tachyarrhythmia between ventricular or supraventricular based on electrocardiographic findings. The distinction between Supraventricular Tachycardia (SVT) and Ventricular Tachycardia (VT) is critical because inappropriate acute management of a VT often results in poor outcome. Almost all of diagnostic criteria are used for differentiating VT from SVT with aberrancy in wide‐­complex tachycardia form, while narrow‐­complex tachycardia is almost always considered as an SVT. However, there is a VT involving His‐­Purkinje re‐­entry path that produces relatively narrow QRS‐­complex.

Methods:

Case Description: A 84‐­year‐­old female came to our emergency department, complaining shortness of breath. This patient had history of advanced HF (NYHA functional class IV). Her shortness of breath deteriorated and accompanied with upper back discomfort within last week. She was tachycardic (Heart Rate 140 bpm) and dyspneic (Respiratory Rate 32/min) with Blood Pressure 108/69 mm Hg and 99% SaO2 in simple mask oxygenation. A 12‐­lead electrocardiogram (ECG) showed a regular, monomorphic, relatively narrow QRS complex (QRS duration 136 ms) tachycardia with RBBB morphology, left superior axis (frontal axis −70o), and also there were several fusion beats and atrioventricular (AV) dissociation (Figure 1). Chest radiography showed cardiomegaly and early pulmonary edema. Intravenous loading continued with continuous infusion of amiodarone was given to her. Her ECG then converted to sinus rhythm with different QRS morphology and axis from tachycardia episode (Figure 2).

Result:

Discussion: Her surface ECG didn't show typical form of VT, such as concordance of the QRS complex in all precordial lead, R‐­S interval >100 ms, Josephson's sign, or initial R in aVR. Diagnostic algorithms including Brugada, Vereckei, Griffith, Bayesian, or R‐­wave Peak Time are used for wide‐­complex tachycardia. Understanding of traditional criteria of VT is very useful in the setting of narrow complex presentation (Table 1). The presence of AV dissociation and fusion beat is quite specific for VT. RBBB morphology with left axis and qR pattern in V1 in relatively narrow (<140 ms) QRS‐­complex consistent with fascicular VT (FVT). Based on Segal criteria2 (Fig. 3), the ectopic focus came from posterobasal or posteromedial origin, as well as posterior fascicular VT is the most common among FVT.3 Verapamil wasn't chosen to terminate her VT because of its cardiac depressive effect.

Conclusion:

Fascicular VT is present in relatively narrow complex VT involving Left Ventricle His‐­ Purkinje system, usually the left posterior fascicle. Differentiating FVT from SVT is often difficult with the usual diagnostic algorithm. Understanding traditional criteria of VT is useful to diagnose FVT and lead to the best treatment to terminate.

Keywords: Narrow‐­complex tachycardia, Fascicular Ventricular Tachycardia, Left Posterior Fascicular VT, Heart failure.

Table 1 Traditional criteria favor VT⁴. In RBBB pattern tachycardia, unusual R/S pattern in V1 and V6 favor VT

Traditional criteria favor VT
AV dissociation
Fusion beat
Capture beat
In LBBB pattern, QRS duration > 160 ms
In RBBB pattern, QRS duration > 140 ms
Northwest axis
In RBBB pattern, left axis deviation
In LBBB pattern, right axis deviation
Positive or negative concordance in precordial leads
In RBBB pattern, R, qR, Rs, or Rr’, or R > 40 ms in V1
In RBBB pattern, S > R, QS, qR, or R in V6
In LBBB pattern, R > 30 ms, R‐­S interval > 70 ms, or Josephson sign in V1‐­2
In LBBB pattern, qR or QS in V6
Initial R wave in aVR

AP19‐­01229

Earlier PVC transition zone in V2 and V3 predicts higher successful rate of left ventricular summit ventricular arrhythmias radiofrequency catheter ablation

Dwi Yuda Herdanto, Sunu Budhi Raharjo, Dony Yugo Hermanto, Dicky Armein Hanafy, Yoga Yuniadi

National Cardiovascular Center Harapan Kita, Indonesia

Introduction:

Radiofrequency ablation of ventricular arrhythmias (VAs) originating from left ventricular (LV) summit is a challenge. This region is the highest portion of the LV epicardium, near the bifurcation of the left main coronary artery (LMCA), and accounts for up to 14.5% of LV VAs. LV summit VAs have various anatomical limitation, making it difficult and often need multiple approaches for mapping and ablation. We report the outcomes of radiofrequency ablation of LV summit VAs and the clinical and ECG features associated with successful ablation.

FIGURE 1 LV summit ablation success rate

Methods:

We recruited all LV summit VAs cases underwent coronary venous system and/or endocardial radiofrequency catheter ablation between January 2015 and July 2019 in National Cardiovascular Center of Harapan Kita, a total of 26 patients (male 57.7%; mean age 51 ± 14 years).

Result:

LV summit VAs ablation success rate was 69%. Patients more frequently in preserved LV and RV function, with hypertension as traditional risk factor. Only 11.5% patients with history of ablation and 57.7% patient with 3D‐­mapping ablation. Majority of patients with LV summit VAs, show LBBB type morphology with inferior axis and negative in aVL lead. About 80.8% patient have earlier VAs precordial lead transition with higher R/S ratio in V2 and V3, than their basic rhythm. All patients have Maximum Deflection Index (MDI) >0.55, suggesting epicardial origin. Earliest ventricular activation in successful ablation was earlier than in failed ablation (44.1 ± 15.3 vs 31.4 ± 16.4 ms). Earlier transition zone of VAs was significantly higher in the successful group. R/S ratio in V2 and V3 were higher and Betensky score was higher in the successful group.

Conclusion:

The LV summit VAs radiofrequency catheter ablation is challenging, with lower success rate rather than ablation of others idiopathic VAs. Patient with successful ablation of LV summit VAs have earlier ventricular activation and earlier VAs precordial lead transition with higher R/S ratio in V2‐­3 and higher Betensky score.

Table 1 Baseline characteristic of LV summit VAs

Total (N = 26)
Age (years)	51 + 14
Male	15 (57.7%)
Reduced LV function (LVEF <40%)	4 (15.4%)
Hypertension	12 (46.2%)
History of PVC ablation	3 (11.5%)
3D Ablation	15 (57.7%)
Total mapping area	2 (1‐­3)
Mapping coronary sinus	17 (65.4%)
Mapping Below LCC	22 (84.6%)
Mapping RVOT	21 (80.8%)
Earliest activation (ms)	40.2 + 16.4
Duration of procedure (min)	230 + 77
PVC with LBBB type	21 (81%)
Inferior lead PVC with positive axis	26 (100%)
Lead I PVC with negative axis	16 (61.5%)
Lead aVL PVC with negative axis	26 (100%)
PVC or Basic rhythm first precordial transition?
Basic rhythm transition first	2 (7.7%)
PVC transition first	21 (80.8%)
Same transition	3 (11.5%)
Betensky score	1.2 + 0.9
MDI	0.63 + 0.05

Table 2 Comparison of LV summit VAs clinical characteristic and ECG feature

Success (N = 18)	Failed (N = 8)	P value
Age (years)	51 + 14	51 + 13	.987
Male	11 (61.1%)	4 (50%)	.683
Reduced EF (<40%)	3 (16.7%)	1 (12.5%)	.786
Hypertension	10 (55.6%)	2 (25%)	.193
History of PVC ablation	1 (5.6%)	2 (25%)	.152
3D ablation	12 (66.7%)	3 (37.5%)	.169
Total mapping area	2 (1‐­3)	2 (2‐­3)	.807
Mapping coronary sinus	13 (72.2%)	4 (50%)	.272
Mapping below LCC	15 (83.3%)	7 (87.5%)	.786
Mapping RVOT	13 (72.2%)	8 (100%)	.097
Earliest activation (ms)	44.1 + 15.3	31.4 + 16.4	.067
Duration of procedure (min)	233 + 58	227 + 105	.907
PVC with LBBB type	14 (77.8%)	7 (87.5%)	.562
Inferior lead PVC with positive axis	18 (100%)	8 (100%)	–
Lead I PVC with negative axis	12 (66.7%)	4 (50%)	.42
Lead aVL PVC with negative axis	18 (100%)	8 (100%)	‐­
PVC or Basic rhythm first precordial transition?
Basic rhythm transition first	1 (5.6%)	1 (12.5%)	.015
PVC transition first	17 (94.4%)	4 (50%)
Same transition	0 (0%)	3 (37.5%)
Betensky Score	1.6 + 1.39	0.91 + 0.5	.144
V3: (R/R+S)PVC / (R/R+S)SR	1.65 + 0.9	1.1 + 0.6	.196
MDI	0.6 + 0.05	0.6 + 0.06	.716

AP19‐­01235

Long‐­term outcome of catheter ablation for electrical storm

Junji Morita, Kenichi Hiroshima, Yohei Sadohara, Rei Kuji, Jun Hirokami, Kengo Korai, Masato Fukunaga, Michio Nagashima, Kei Yamamoto, Kenji Ando

Kokura Memorial Hospital, Japan

Introduction:

The effectiveness of catheter ablation (CA) for electrical storm (ES) has been reported, however, long‐­term outcome is still unknown.

Methods:

We enrolled consecutive patients undergoing CA for ES from Jan. 2006 to Apr. 2019 in large single center. ES was defined as the occurrence of ≥ 3 episodes of ventricular tachycardia (VT)/ ventricular fibrillation (VF). Procedure of CA: CA was performed using 3D mapping system with moderate sedation CA strategy: Conducting channels were defined with substrate mapping, activation mapping and entrainment maneuvers depending on VT tolerance. End point was divided into 4 groups: (1) non‐­inducibility of any VT (2) non‐­inducibility of clinical VT (3) inducibility of clinical VT (4) no programmed stimulation

Result:

The study population consisted of 85 patients; mean age 70 ± 12, female 18%, ischemic heart disease 55%. At a median follow‐­up of 30 months (mean, 30 ± 28 months), 26 patients (31%) died, 15 as a result of cardiac causes (18%). The incidence of recurrence ES was lower in non‐­inducibility of any VT group (group 2 vs group 1: HR 4.6; 95% CI 1.26–21.5), (group 3 vs group 1 : HR 9.4; 95% CI 2.48–44.8).

Conclusion:

At a median follow‐­up of 30 months, 26 patients (31%) died, 15 as a result of cardiac causes (18%). The recurrence of ES was lower in non‐­inducibility of any VT group.

AP19‐­01247

Coronary steal syndrome in coronary artery fistula presenting the four‐­timers recurrent ventricular tachycardia

Carol Natasha, Elizabeth Marcella, Karlina Alferinda, Joey Martinus Sidarta, Niyata H. Karunawan, Vito Anggarino Damay

Faculty of Medicine Universitas Pelita Harapan, Indonesia

Introduction:

Background: Coronary Arterial Fistula (CAF) is a connection between one or more of the coronary arteries and a cardiac chamber or great vessel. We describe a rare case of a 60‐­year‐­old male who had a fistula proximal left anterior descending coronary artery to apex left ventricle, that causing coronary ischemia with recurrent monomorphic sustained ventricular tachycardia (VT).

Methods:

Case Description: A 60‐­year‐­old male came to the ED with chest pressure associated with palpitation, nausea, vomiting, and diaphoresis for four hours. The patient had a history of the three‐­timers Recurrent VT monomorphic. The patient was alert and his blood‐­pressure was 80/60, heart‐­rate 190×, respiratory‐­rate 32×. Physical examination was normal. His laboratory revealed: cardiac enzymes and electrolytes were normal. On 12‐­lead EKG showed sustained monomorphic VT with a right bundle branch block pattern and a superior QRS axis. Echocardiogram showed left‐­ventricle (LV) dilatation abnormal and segmental LV hypokinetic anteroseptal with ejection‐­fraction 55%. Coronary Angiography revealed Fistula Proximal Left Anterior Descendent to Apex Left Ventricle with Double Vessel Disease. He was found to be in unstable pulsatile VT and his arrhythmia was converted to sinus rhythm by cardioversion with 100 J synchronized. VT was terminated to sinus rhythm with ECG pattern showed ST depression in anterolateral and inferior leads. Patient was given loading Clopidogrel 300 mg Aspirin 300 mg and maintenance therapy injection subcutaneous Fondaparinux 1 × 2.5 mg, MgS04 20% 1 g in 10 minutes, Clopidogrel 1 × 75 mg, Aspirin 1 × 100 mg, Rosuvastatin 1 × 20 mg, Nitroglycerin 1 × 2.5 mg, Bisoprolol 2 × 1.25 mg, Trimetazidine 2 × 20 mg, Perindopril 2 × 2.5 mg.

Result:

Discussion: Coronary fistulae that expand to the left ventricle are known to cause coronary ischemia due to coronary steal syndrome. Complications of coronary artery fistula include ‘steal’ from the adjacent myocardium causing myocardium scars. There was a relationship between structural changes and recurrent VT represented by reentry. In this case, the patient was diagnosed with recurrent monomorphic sustained ventricular tachycardia (VT), which has not previously been reported ever that VT was caused by coronary artery fistula.

Conclusion:

A Fistula between the proximal left anterior descending coronary artery and the LV can lead to coronary steal syndrome. We hypothesized that recurrent VT was caused by myocardium scars due to coronary steal syndrome.

AP19‐­01258

Purkinje premature ventricular contraction induced ventricular fibrillation

Vihang Shah, Debabrata Bera, Sachin Yalagudri, Daljeet Kaur Saggu, Soumen Devidutta, Ashutosh Ashutoshvani, Rakesh Sarkar, Calambur Narasimhan

Pranayam Lung and Heart Institute, India

Introduction:

Idiopathic Ventricular fibrillation (IVF) is a rare cause of sudden cardiac arrest (SCA). It is reported in 6.8% of all patients surviving a cardiac arrest and is more common in young patients. IVF is a diagnosis of exclusion in patient who has survived a VF episode without any identifiable cause. In majority of cases, VF is triggered by premature ventricular contraction (PVC) from purkinje network. Ablation of these VF triggers is associated with good longterm outcome.

Methods:

A 45 years lady, known hypertensive for 2 years presented with recurrent episode of palpitations and 2 episode of syncope. She was found to have ventricular tachycardia/fibrillation. As there were multiple episodes of VT/VF, she was managed in the ICU with xylocard, amiodarone and metoprolol, and repeated cardioversions and defibrillation. ECG revealed short coupled (280 msec) Monomorphic PVC giving rise Ventricular fibrillation (VF) (Figure 1). Morphology of the triggering PVC was similar in all the VT/VF episodes. 2 D ECHO and Cardiac MRI was normal. Further evaluation showed normal metabolic parameters and no evidence of structural heart disease on cardiac MRI scan and Cardiac PET scan. Patient was sedated and intubated. However the number of VF storm continued. Patient was taken for catheter ablation under 3 D electroanatomic mapping. Mapping and ablation was done using 3.5‐­mm open irrigated‐­tip ablation catheter (Thermocool, Biosense webster). A 3 D electroanatomic map was created using the earliest activation of PVC origin site along the left purkinje network of Left ventricle septum. Earliest site was tagged. Ablation (30 W/60°) was performed at the earliest activation site (local purkinje potential) which initiated the non‐­sustained VF .RF Lesions were consolidated by ablation in the surrounding 1‐­2 cm². No more PVC appeared for a waiting period of 1 hour and with 20 mcg of isoprenaline. Post procedure, patient was stable and discharged. At 2 months follow up, patient did not have any VF episode.

Result:

N/A

Conclusion:

IVF is a rare cause of SCA. It can present as a an electrical storm. Catheter ablation of the Purkinje trigger is effective therapy for this condition.

AP19‐­01279

High‐­power and short‐­duration ablation with titration for premature ventricular contractions: a retrospective analysis

Hongmei Zheng, Heng Cai, Li Xue, Hongshi Li, Mei Liu, Xin Du, Ye Cheng, Liang Zhang, Kejia Zhu, Yuxia Gao, Qing Yang

Tianjin Medical University General Hospital, China

Introduction:

Radiofrequency (RF) ablation is a well‐­established approach to treat premature ventricular contractions (PVC) and is associated with good outcomes

Methods:

We conducted a retrospective review of 31 patients with premature ventricular contractions in general hospital of Tianjin Medical University from December 2014 to December 2017. Clinical data, the ablation power, the ablation duration and the effective target sites were reviewed in 31 cases. The patients underwent radiofrequency ablation with high‐­power ablation due to failure to conventional RF applications (30‐­35 W). (High‐­power ablation includes 50 W/8 s, 60W/4‐­6s, 70W/4s, 80W/2s, and 100W/2s) When the power was 50W, each discharge would take 8 seconds and repeated 10 times. If the number of PVCs decreased, PVCs still not disappeared, we would increase the ablation power immediately. Discharge duration would be decreased with the increasing of the power, (4‐­6 seconds for 60W, 4 seconds for 70 W). When the power increased to 80‐­100 W, the discharge duration would reduce to 2 seconds. It was defined as acutely successful of the procedure that PVCs disappeared after ablation and still did not recur after 20 minutes.

Result:

There were no intraoperative complications in the total of 31 cases. Among them, 29 cases were successful with success rate of 93.55%. However there were also 2 cases (6.45%) failed. Of all the cases, the total ablation power was 66.45 ± 20.88 (50‐­100) W and the ablation duration was 311.65 ± 241.91 (80‐­950) seconds. Among the 29 patients that were successfully ablated, the effective ablation sites showed as follows: PVCs originated from aortic sinus in 15 cases (51.72%); AMC sources were in 9 cases (31.03%); 1 case (3.45%) was ablated successfully in the subaortic region corresponding to the earliest points of aortic sinus; 2 cases (6.90%) were in summit area; 1 case (3.45%) was found in the left posterior papillary muscle region, and 1 case (3.45%) was found at the site of 12 o ‘clock in the tricuspid annulus. Among the 31 patients, 8 patients (27.59%) were ablated in multiple sites successfully.

Conclusion:

High‐­power and short‐­duration with titration RF applications can be a effective and safe manner to PVCs, which can increase the success rate of radiofrequency catheter ablation.

AP19‐­01296

Telemetry monitoring was associated with improved survival in hospitalized patients with cardiopulmonary arrest

Lori Li, Angela Fox, Albertine Beard, Robin Rabey, Venkat Tholakanahalli, Jian‐Ming Li

VA Medical Center, United States

Introduction:

The natural history of In‐­hospital cardiac arrest (IHCA) is different from out‐­of hospital cardiac arrest (OHCA). However, the outcomes of in‐­hospital CPRs according to the initial rhythm have not been well studied.

Methods:

All IHCA cases were included between Oct 2011 and June 2019. Pulseless electric activity (PEA), Asystole, pulseless ventricular tachycardia and fibrillation (VT/VF) from in‐­hospital CPR records were verified independently by two separate physicians. The status of the telemetry monitoring at the time of IHCA was obtained from the electronic medical record.

Result:

Of the 63 803 hospitalized patients in 8 years, 326 (0.51%) IHCAs occurred in 281 consecutive patients. The mean age was 69.3 ± 14.1 years old, all of whom were male. The percentages of PEA, pulseless VT/VF, Asystole and undocumented events were 55.2%, 28.5%, 13.2%, and 3.1%, respectively. Return of spontaneous circulation (ROSC) was achieved in 60% of CPR procedures, with the rate of survival to discharge (RSTD) of 27.6% (Table 1). Cardiac monitoring before IHCA was associated with improved RSTD, as compared to no cardiac monitoring (30.7% vs 17.5%, risk ratio 1.75, preliminary), with the most impact on patients with Asystole arrest (28% vs 5.6% for 30‐­day survival, risk ratio 5.0, 16% vs 5.6% for RSTD, Table 2). No increased IHCA events were observed during the weekend or evening hours.

Conclusion:

Telemetry monitoring at the time of IHCA was associated with improved survival. Its impact on CPR outcome, especially for patients with Asystole arrest, requires further study.

Table 1 Outcome of in‐­hospital CPRs according to the initial rhythm

Type of arrest	PEA  arrest	Asystole	VT/VF	Unknown	Total
No of arrest (%)	180  (55.2%)	43 (13.2%)	93  (28.5%)	10  (3.1%)	326  (100%)
No of ROSC (%)	99  (55%)	19  (44.1%)	68  (73.1%)	10  (100%)	196  60.1%
No of 30‐­−‐d survival  (%)	37  (20.6%)	8  (18.6%)	40  (43%)	9  (90%)	94  28.8%
No of STD  (%)	36  (20%)	6  (14.0%)	39  (41.9%)	9  (90%)	90  27.6%

ROSC, Return of spontaneous circulation; STD, survival to discharge; RR, risk ratio.

Table 2 Outcome of In‐­hospital CPRS according to cardiac monitoring status

M/NM	PEA	Asystole	VT/VF	Total
No.  M/NM	95/85	25/18	82/11	202/114
ROSC  M/NM %RR	55.8/  49.4  1.13	48/27.8  1.73	74.4/63.6  1.17	62.4/47.3  1.32
30d survival  rate,  M/NM%  RR	22.1/18.8  1.18	28/5.6  5.0	45.1/27.3    1.65	32.2/17.5  1.84
RSTD  M/NM %  RR	22.1/18.8  1.18	16/5.6  2.85	45.1/27.3  1.65	30.7/17.5  1.75

M/NM, telemetry/non‐­−‐telemetry bed; ROSC, return of spontaneous circulation; RSTD, rate of survival to discharge; RR, risk ratio.