Syncope and SCDs

AP19‐­00014

A case of recurrent syncope due to sick sinus syndrome detected by implantable loop recorder

Hideaki Sato, Takayuki Eizawa, Ryuichi Kai, Kenichi Ito

Asama Nanroku Komoro Medical Center, Japan

Introduction:

Syncope is a clinical symptom for many kinds of diseases. The reasons for some syncope are still not clear even after a comprehensive and systematic examination, known as unexplained syncope.

Methods:

A 77‐­year‐­old male suddenly presented recurrent syncope. Twelve‐­lead electrocardiogram (ECG) on admission showed sinus rhythm. Twenty‐­four hour monitoring ECG performed during hospitalization did not reveal an arrhythmia. Syncope etiology remains unexplained we inserted Implantable Loop Recorder (ILR).

Result:

The instrument recorded the first syncope at a time of recurrence for the sick sinus syndrome in 30 days after ILR. The patient was thus diagnosed as arrhythmic syncope and received an operation with pacemaker. During 10 months of follow‐­up, he was asymptomatic and free of arrhythmic events.

Conclusion:

The ILR is useful examination device for patients suffering from syncope with suspected cardiac rhythm due to its long monitoring time, low infection rate and high safety. It possesses high clinical value in the diagnosis of patients with arrhythmic syncope.

AP19‐­00030

Hurdle, unexpected surprise awaits Micra

Kantha Rao Narasamuloo, Ahmad Faiz Mohd Ezanee, Yi Zhi Cheng, Saravanan Krishinan

Hospital Sultanah Bahiyah, Malaysia

Introduction:

Sixty years old lady with End Stage Renal failure requiring regular dialysis. Arteriovenous fistula (AVF) was created over the right arm. However her AVF failed, an attempt was made to create over left arm, unfortunately, it is not suitable yet for creation of new AVF. She proceeded with permanent catheter insertion over the femoral vein. Catheter insertion over the right femoral vein failed, therefore proceeded with permanent catheter insertion over the left femoral vein which was successful. Recently admitted for symptomatic bradycardia with a pause of 6.5 seconds. The decision to implant pacemaker was made and the leadless pacer was decided to be the best option to preserve her future vascular access. Micra from Medtronic was chosen.

Methods:

N/A.

Result:

Only access available was right femoral vein as left femoral vein has a permanent catheter for haemodialysis. The venous puncture was done however unable to pass the guide wire towards IVC. A cine image was taken and noted wire is in the right course of direction however unable to advance more than 70% of its length and the vessel was heavily calcified. 6 French femoral sheaths were inserted and contrast injection is done under fluoroscopy. Noted right common iliac vein occluded!! What is the next step?? She needs access to implant Micra.!! A peripheral intervention wire (V0.018) was used to open the occlusion guided by multi‐­purpose catheter (MPA) however failed. We are Electrophysiologist with little knowledge of peripheral intervention and poorly equipped for peripheral intervention. We believe a stiffer wire is needed to break the complete total occlusion of the distal common iliac vein. Therefore the same wire (V0.018)was used but this time distal end (stiffer) of the wire together with MPA able to cross the lesion. Once we cross the lesion. MPA catheter was glided upwards and the V0.018 wire was removed. A contrast shot was taken to ensure we are within the lumen and lucky enough to be in the lumen and contrast actually flow towards IVC. This is followed by reinsertion of V0.018 wire in a proper method. The V 0.018 wire was advanced together with MPA towards inferior vena cava. Then, the wire was replaced with Amplatz super stiff wire and MPA was removed. The lesion was predilated using peripheral balloon 12 × 40 mm and inflated at 10 atm several times and finally able to establish a good diameter of the right common iliac vein.

Conclusion:

This has paved the path for Micra delivery sheath to be run over the Amplatz wire and managed to implant Micra leadless pacemaker with good parameters and created new access for future dialysis catheter to be inserted over the right femoral vein. Lessons learned: (a) Choosing the rightful patient for Micra implantation, (b) Basic knowledge of peripheral intervention, (c) Adequate history taking prior to the procedure will help in better preparation of the patient pre‐­implantation, (d) Understanding the Micra retrieval technique much useful.

AP19‐­00034

Baroreflex sensitivity is associated with the incidence of ventricular fibrillation in patients with the augmentation of J‐­wave

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

Oita University, Japan

Introduction:

J‐­waves are seen in both patients with idiopathic ventricular fibrillation (VF) and the general population. J‐­waves exhibited diurnal variability or bradycardia‐­dependent augmentation characteristics in patients with idiopathic VF, suggesting an association between autonomic nervous activity and the occurrence of VF. Baroreflex sensitivity (BRS) is believed to reflect reactive parasympathetic nerve activity. We investigated the relationship between VF occurrence and BRS in patients with the augmentation of J‐­wave.

Methods:

We enrolled 12 consecutive patients with idiopathic VF (early repolarization syndrome group: ERS) and 29 control subjects who had manifested J‐­waves (control group: CNT). We investigated their BRS by phenylephrine method. Furthermore, all 12 ERS patients were examined cardiac 123I‐­ metaiodobenzylguanidine (MIBG) scintigraphic findings. Implantable cardioverter‐­defibrillators (ICDs) were implanted in all 12 patients, and 3 patients experienced ICD shock delivery due to the recurrence of VF after ICD implantation (recurrent VF group).

Result:

BRS value in ERS patients was significantly higher than that in CNT subjects (10.0 ± 3.1 vs 6.0 ± 5.1 mmHg/s, P = 0.014). Furthermore, in ERS patients, BRS value in recurrent VF group was significantly higher compared with that in non‐­recurrent VF group (13.5 ± 2.3 vs 8.9 ± 2.4 mmHg/s, P = 0.015). On the other hand, in the 123I‐­MIBG testing, the mean heart‐­to‐­mediastinum (H/M) ratio and washout rate (WR) was not significantly different between recurrent VF and non‐­recurrent VF groups (early H/M: P = 0.67, delayed H/M: P = 0.33, WR: P = 0.45).

Conclusion:

Our results suggest that the increased BRS value by phenylephrine method may be a useful tool to identify the high risk of VF in subjects with augmentation of J‐­waves.

AP19‐­00039

You only die twice: A case of sudden cardiac arrest in a patient with severe apical hypertrophic cardiomyopathy and a coronary anomaly

Seth Goldbarg

New York Presbyterian/Queens, United States

Introduction:

Apical hypertrophic cardiomyopathy (AHCM) is an uncommon variant of hypertrophic cardiomyopathy which may carry less risk of sudden cardiac arrest (SCA) than others phenotypes. A 66 years old M who had previously suffered resuscitated cardiac arrest attributed to severe AHCM was found years later to have an anomalous origin of the right coronary artery from the left coronary sinus of valsalva, casting doubt on the presumed cause of his arrest.

Methods:

A 66 year old man presented with worsening angina and exertional dyspnea. He had a history of AHCM, SCA due to ventricular fibrillation, and ICD placement. He reported progressive dyspnea on exertion. His EKG showed atrial fibrillation with right ventricular pacing. The patient underwent exercise stress transthoracic echocardiography exercise for 5 minutes (6 METS), stopping due to dyspnea. The peak intracavitary gradient was 55 mm Hg. Coronary angiography was performed, which revealed an anomalous right coronary artery (aRCA) originating from the left coronary cusp, coursing anteriorly between the pulmonary artery and the ascending aorta. He turned down surgical evaluation for bypass of the anomalous coronary artery.

Result:

AHCM and anomalous coronary anatomy are both rare causes of SCA. We present a case of SCA in a man with severe AHCM later found to have a coronary anomaly. Anomalous coronaries have a reported incidence of 0.6%‐­1.3% in autopsy series; anomalous origin of the RCA from the left coronary cusp between the great vessels is 0.026%‐­0.25%. Coronary anomalies may account for less than 1% of SCA, though the true risk of SCA in a given coronary anomaly is not known. Apical HCM is generally felt to have a low risk of malignant arrhythmia, though numerous case reports and some case studies suggest an increased mortality risk.

Conclusion:

Apical HCM and anomalous right coronary artery (aRCA) are both rare causes of SCA. We highlight a case of SCD where both phenotypes existed simultaneously in a patient who suffered SCA. This case highlights the need for comprehensive testing in patients with SCA when a rare potential cause is initially found.

Left to right: 4 chamber view demonstrating a spade‐­like left ventricle with mid‐­cavity obliteration; Cardiac catheterization showing RCA origin from left sinus of Valsalva; Cardiac CT with arrow demonstrating RCA coursing between the aorta and pulmonary artery.

AP19‐­00080

Problems with ICD implantation for foreign technical intern trainees in Japan: A case of Vietnamese Brugda Syndrome experienced at our hospital

Shigetoshi Sakabe

Ise Red Cross Hospital, Japan

Introduction:

Japan has a labor shortage problem due to the declining birthrate and aging population. Therefore, in recent years, we have been recruiting labor from Asian countries. The Japanese government has established the Technical Intern Training (TIT) Program. And foreign workers who work on time‐­limited visas are called TITs. In Japan in 2018, there was a report that some male TITs from Vietnam were suddenly dying and were discussed in the National Assembly. Those deaths were considered overworked deaths.

Methods:

We were consulted a Vietnamese patient who needs ICD implantation. We report the institutional issues in the present situation.

Result:

Case: One day in 2017, a 26‐­year‐­old Vietnamese TIT man lost consciousness and injured his face. He was transported to a nearby medical institution and electrocardiogram was taken. Type 1 Brugada electrocardiogram was recorded and he was transferred to our hospital. He had been fainting before. He had no family history of sudden death. Echocardiography showed no abnormal findings. And signal averaged electrocardiography showed positive findings of late potential. As a result of scrutiny, he was diagnosed with Brugada syndrome to be implanted with ICD. Because the patient was eligible for residence and had health insurance, the costs for ICD implantation were to be reduced. However, the treatment was limited during his stay in Japan, and no extension of work visa was permitted. Treatment in Vietnam was uninsured and generator replacement was not possible for economic reasons. The patient gave up and returned home early. Discussion: It is estimated that a certain number of TITs from Asia suddenly die from Brugada syndrome. However, it has not been diagnosed correctly, and is considered unknown death. They should receive a full medical checkup, including an electrocardiogram, at work. In this case, it is assumed that the patient was not convinced. We should provide a company‐­independent medical interpreter.

Conclusion:

Japan has a universal insurance system and TITs are exempt from medical expenses at the time of ICD implantation. However, the Japanese government does not recognize their permanent residence, and they cannot receive treatment after their visa expires. We are required to consider the medical environment after returning home.

AP19‐­00088

Usefulness of genetic screening for long QT syndrome in the school‐­based electrocardiographic screening programs

Megumi Fukuyama, Seiko Ohno, Junichi Ozawa, Koichi Kato, Takeru Makiyama, Minoru Horie

Shiga University of Medical Science, Japan

Introduction:

In Japan, school‐­based electrocardiographic screening program at the admission to primary school (PS), middle school (MS), and high‐­school (HS) has been established. Inherited arrhythmia diseases have been often pointed out in this program, especially long QT syndrome (LQTS). We aimed to evaluate the usefulness of genetic analysis in the screening program.

Methods:

The study cohort consists of 378 probands at age of 6‐­7 (PS, n = 78), 12‐­13 (MS, n = 177), and 15‐­16 (HS, n = 123), who received genetic analysis in our institute during the last decade (2007‐­2017). Extracted LQTS probands were divided into 4 groups; (a) screening + asymptomatic, (b) screening + symptomatic, (c) non‐­screening + symptomatic, (d) non‐­screening + asymptomatic. About 4 groups, we investigated their clinical and genotype characteristics.

Result:

The number of the probands with LQTS were 259; 59 (76%) in PS, 132 (75%) in MS, 68 (55%) in HS, respectively. Among them, screening based LQTS probands were 167 including 9 symptomatic patients; 46 (78%) in PS, 84 (64%) in MS, and 37 (55%) in HS. In screening based probands, 96 (57%) probands carried mutations; 40 in PS, 38 in MS, 18 in HS, and the mutations in KCNQ1 gene (LQT1) were the most frequent in PS and MS group (n = 22, and 17), and those in KCNH2 (LQT2) in HS group (n = 7). Surprisingly, 9 of CACNA1C variants (LQT8) were identified which were as frequent as SCN5A variants (LQT3, n = 10). Most of symptomatic children were in non‐­screening, and syncope was the most frequent. Notably, fatal arrhythmic attacks were shown in only non‐­screening group, and increased in HS group. 17 of 19 probands with fatal arrhythmic attacks carried mutations of LQTS causative gene (n = 3 in PS, n = 8 in MS, and n = 6 in HS). Additionally, mean QTc intervals were longer in mutation carriers (>480 milliseconds) in the all of generations, and most of probands were identified causative gene mutation of LQTS (>90%) in the group with Schwartz score ≥3.5. Summarizing the above, the cases with (a) QTc interval ≥ 480 milliseconds, (b) Symptomatic, (c) Schwartz score ≥3.5 are highly carrying causative mutations of LQTS.

Conclusion:

More than half of the LQTS patients who were detected in the school‐­based electrocardiographic screening programs carried the causative mutations. The mutation detection rate was the highest in the PS. Therefore, genetic analysis should be performed in their younger age, and it would be useful for their treatment.

AP19‐­00177

Young man: Palpitation and syncope

MAM Chandara

Calmette Hospital, Cambodia

Introduction:

Ebstein's anomaly is a rare congenital heart disorder, accounting for <1% of all cases of congenital heart disease. It is a congenital malformation of the heart that is characterized by apical displacement of the septal and posterior tricuspid valve leaflets, leading to atrialization of the right ventricle with a variable degree of malformation and displacement of the anterior leaflet.

Methods:

Case report: WPW with Ebstein's Anomaly. Ablation by Radiofrequency.

Result:

Successfully.

Conclusion:

Rare case of congenital heart disease Ebstein's Anomaly associated with WPW and successfully treated by ablation by Radiofrequency.

AP19‐­00178

Cardioneuroablation as an alternative for a pacemaker in a young patient suffering several syncopes due to functional sinus arrest and complete atrioventricular block

Thiago Guimarães Osório, Rafael Flores, Carlos Thiene Cunha Pachon, Enrique Indalecio Pachon Mateos, Jose Carlos Pachon Mateos, Gian‐Battista Chierchia, Carlo deAsmundis

Vrije Universiteit Brussel, Universitair Ziekenhuis Brussel, Brussels, Belgium., Belgium

Introduction:

Several clinical conditions comprise the balance between the sympathetic and parasympathetic tone. An imbalance in the autonomic nervous system with an increase of the vagal tone and a decrease of the sympathetic tone might result in cardioinhibition, sinus bradycardia, or transient atrioventricular block. The most common examples are the neurocardiogenic syncope (cardioinhibitory or mixed), functional transient AVB, or carotid sinus syndrome in patients without significant cardiopathy. These patients can be extremely symptomatic. Even with studies demonstrating that the implant of a pacemaker might not solve the problem, the indication of the latter might be necessary. As an alternative, in the nineties, a method to modulate the parasympathetic tone, called “Cardioneuroablation” removing or attenuating the cardioinhibitory response, was specifically developed to treat those patients 1‐­4.

Methods:

Here, we report a case of a patient with recurrent severe cardioinhibitory syncope, where the Cardioneuroablation was performed with successes.

Result:

A 55‐­years‐­old woman, with a history of depression and syncopes, started 8 years ago, being treated as a neurological cause since then. Among the exams performed were echocardiogram without structural disease and preserved function, 24 hours Holter showing rare supraventricular extrasystoles without bradycardia, pauses or complex arrhythmias. A positive tilt test for neurocardiogenic syncope with a cardioinhibitory response with a 60‐­second of pause, convulsion and sphincter release (Figure 1). On 03/09/18, she underwent Cardioneuroablation with extracardiac vagal stimulation to validate the vagal denervation during the procedure (Figure 2) indicating the endpoint of the proposed treatment. The patient followed without symptoms in the immediate postoperative period, only with expected mild sinus tachycardia, controlled with a beta blocker.

Conclusion:

Nine months later, she is asymptomatic, with normal life. A new tilt test was performed, with a negative result for neurocardiogenic syncope and presented a steady heart rate response throughout the examination (Figure 3).

FIGURE 1 An ECG of the tilt table test, previous the procedure, showing a cardioinhibitory response of 60 seconds

FIGURE 2 Extracardiac vagal stimulation of 5 seconds before the procedure, showing a complete cardioinhibition response during and after the stimulation (left panel). The same extracardiac vagal stimulation showing no vagal response, which confirms an adequate parasympathetic modulation after the procedure

FIGURE 3 A negative Tilt table test 5 months after the procedure. Worth mentioning, the steady heart rate response throughout the exam. bpm, Beats per minute; FC, Heart rate; mmHg, millimeter of mercury; PD, Diastolic blood pressure; PS, Systolic blood pressure

AP19‐­00245

Prognosis of cardiac sarcoidosis in Japanese patients with an implantable cardioverter defibrillator ‐­ with versus without other organ involvement

Miyo Nakano; Yusuke, Kondo; Masahiro, Nakano; Takatsugu, Kajiyama; Kazuo, Miyazawa; Tomohiko, Hayashi; Ryo Ito, Haruhiro Takahira, Yoshio Kobayashi

Department of Cardiovascular Medicine, Chiba University Graduate School of Medicine, Japan

Introduction:

Cardiac sarcoidosis (CS) is a granulomatous disorder affecting multiple organ systems including lungs, lymph nodes, a liver, skin, eyes, and gastrointestinal tract. The leading causes of death in patients with CS are cardiac arrhythmias, progressive heart failure, and progressive respiratory failure. Patients with CS are at high risk of sudden cardiac death from ventricular arrhythmias. Implantable cardioverter defibrillators (ICDs) have been used for primary and secondary prevention of sudden death in patients with CS. However, there are few reports about the clinical prognosis in CS patients with ICD. The purpose of this study was to identify the difference between prognosis of Japanese CS patients who received an ICD with and without other organ involvement.

Methods:

We retrospectively analyzed the database of our ICD clinic. Of 498 consecutive ICD patients, 34 patients (6.8%) were diagnosed with CS. All of CS patients received steroid therapies. We defined CS patients without other organ involvement as isolated CS, and with other organ involvement as non‐­isolated CS. We examined their background, left ventricular ejection fraction before and after steroid therapies, the incidence of appropriate ICD therapies, and the incidence of hospitalization and death.

Result:

Diagnosis of CS was made by cardiac magnetic resonance (CMR) (n = 7), positron emission tomography (PET) (n = 14), CMR and biopsy (n = 4), CMR and PET (n = 12), PET and biopsy (n = 8), late enhanced cardiac computer tomography (CT) and CMR (n = 5), and CT and PET (n = 5). Figure shows the patients background and the clinical outcomes during the follow‐­up. Of 34 CS patients with an ICD, 13 (38%) had isolated CS. Of 13 patients, 6 (36%) were male, age was 59 ± 12 years, follow‐­up period was 68 ± 57 months, and left ventricular ejection fraction was 38 ± 12%. During the follow‐­up period, appropriate therapies occurred in 4 of 13 (31%) isolated CS patients and 6 of 21 (29%) non‐­isolated CS patients (P = 1.0). Two of 13 (16%) isolated CS patients were hospitalized for heart failure, compared with 7 of 21 (33%) non‐­isolated CS patients (P = 0.43).

Conclusion:

The prognosis Japanese patients with CS was not good. There was no significant difference between the prognosis of CS with and without other organ involvement in this population.

Patient Characteristics and Major Events

(i) Patient characteristics

	n = 34	Non‐­isolated CS (n = 21)	Isolated CS (n = 13)	P value
Median age at diagnosis, years (IQR)	62 (56‐­69)	62 (58‐­70)	59 (55‐­67)	0.45
Male, n (%)	14 (42)	8 (38)	6 (36)	0.73
Primary prevention, n (%)	22 (65)	13 (62)	9 (69)	0.73
Follow‐­up period (months)	54 (36‐­78)	54 (38‐­78)	53 (31‐­78)	0.53
CRT, n (%)	17 (50)	12 (57)	5 (38)	0.48
LVEF (%) at diagnosis	40 (31‐­45)	40 (30‐­45)	40 (31‐­42)	0.62
LVEF(%)after corticosteroid therapy	42 (32‐­45)	41 (32‐­43)	40 (32‐­45)	0.95
High grade AVB, n (%)	18 (53)	10 (48)	8 (62)	0.50
β‐­blocker, n (%)	33 (97)	20 (95)	13 (100)	1.0

(ii) Major events

	n = 34	Non‐­isolated CS (n = 21)	Isolated CS (n = 13)	P value
Appropriate ICD therapy, n (%)	10 (29)	6 (29)	4 (31)	1.0
Shock therapy, n (%)	5 (15)	3 (14)	2 (15)	1.0
ATP therapy, n (%)	8 (24)	5 (24)	3 (23)	1.0
Hospitalization for arrhythmia, n (%)	9 (26)	7 (33)	2 (16)	0.43
Hospitalization for heart failure, n (%)	9 (26)	7 (33)	2 (16)	0.43
Electrical storm, n (%)	4 (12)	3 (14)	1 (8)	1.0
Death, n (%)	1 (3)	1 (5)	0	1.0

Abbreviations: CS, Cardiac sarcoidosis; CRT, cardiac resynchronization therapy; LVEF, left ventricular ejection fraction; AVB, trio‐­ventricular block

AP19‐­00246

Next‐­generation sequencing based genetic testing can detect concealed cardiomyopathies in patients with idiopathic ventricular fibrillation

Yun Gi Kim, Jong‐Il Choi, Suk‐Kyu Oh, Ki Yung Boo, Do Young Kim, Kwang‐No Lee, Jaemin Shim, Young‐Hoon Kim

Korea University Medicine Anam Hospital, South Korea

Introduction:

Underlying genetic background of idiopathic ventricular fibrillation (IVF) with structurally normal heart remains largely unknown. Next generation sequencing (NGS) has enabled mass‐­ evaluation of genetic variants with reasonable cost. We aimed to identify the culprit genetic variant in IVF patients by utilizing NGS.

Methods:

Blood samples from 78 patients with IVF were obtained from tertiary hospitals in South Korea. Genetic testing of 174 genes known to cause cardiac diseases was performed through Illumina MiSeq platform (Illumina Inc.). Among genetic variants observed, its pathogenicity was determined in accordance with the American College of Medical Genetics (ACMG) guideline.

Result:

Among 78 patients with IVF, 42 patients (53.8%) had at least one pathogenic variant according to ACMG guideline. SCN5A variants were observed in seven patients: five variants were related to Brugada syndrome, one variant was related to long QT syndrome, and the other was unreported variant but in‐­silico mutation prediction model showed potential pathogenicity for Brugada syndrome. Additional two patients had CACNA1C variant known for Brugada syndrome. Two patients were suspected to have long QT syndrome due to variants in KCNE1 and ANK2 gene. Eighteen patients had genetic variants related to arrhythmogenic right ventricular cardiomyopathy (four PKP2, five DSG2, two RYR2, four DSP, two TMEM43, one JUP). Genetic variants related to hypertrophic cardiomyopathy was observed in seven patients: four MYBPC3, two MYH7, and one MYH6 mutations. Six patients had variants related to dilated cardiomyopathy: three TTN, two MYPN, and one LAMA2. Among the pathogenic variants, overall rate of detecting cardiomyopathies was 73.8% (31/42).

Conclusion:

Genetic testing using NGS revealed that substantial proportion of patients with IVF had causative variants in genes responsible for cardiomyopathies, suggesting that lethal ventricular arrhythmia can manifest before the development of an overt phenotype of cardiomyopathy.

AP19‐­00247

Next‐­generation sequencing based genetic testing in patients with sudden cardiac arrest

Yun Gi Kim, Jong‐Il Choi, Jinwoo Ahn, Sanghoo Lee, Kyoung‐Ryul Lee, Suk‐Kyu Oh, Jaemin Shim, Young‐Hoon Kim

Korea University Medicine Anam Hospital, South Korea

Introduction:

Identifying underlying genetic background of sudden cardiac death (SCD) or ventricular fibrillation (VF) in structurally normal heart is often difficult. Next generation sequencing (NGS) has enabled mass‐­evaluation of genetic variants with reasonable cost. We aimed to identify the clinical usefulness of NGS in patients with SCD or documented VF and structurally normal heart.

Methods:

Blood samples from patients with SCD or VF were obtained from tertiary hospitals in South Korea. Genetic testing of 174 genes known to cause cardiac diseases was performed through Illumina MiSeq platform (Illumina Inc.). Among genetic mutations observed, its pathogenicity was determined in accordance with the American College of Medical Genetics (ACMG) guideline.

Result:

Among 77 patients with SCD or VF (22 Brugada syndrome, 11 long QT syndrome, 4 early repolarization syndrome, and 40 idiopathic ventricular fibrillation), 41 patients (53.2%) had at least one pathogenic variant according to the ACMG guideline. SCN5A variants were observed in 14 patients (18%): ten variants were related to Brugada syndrome, two variants were related to long QT syndrome, and the others were unreported variants but in‐­silico mutation prediction models showed potential pathogenicity. Three patients had CACNA1C variant known for Brugada syndrome. Two and one patients were suspected to have long QT syndrome due to variants in KCNE1 and ANK2 gene, respectively. Eight patients had genetic mutations related to arrhythmogenic right ventricular cardiomyopathy. MYBPC3 and MHY7 variant known to cause hypertrophic cardiomyopathy was observed in eight and one patients, respectively. Genetic variants in LAMA2 and DMD genes were also observed in two patients each.

Conclusion:

Genetic testing using NGS in SCD or VF patients revealed that substantial proportion of patients had genetic variants probably responsible for the disease. Genetic testing through NGS can be considered in patients with SCD or VF to elucidate the underlying genetic cause and to guide future therapy.

AP19‐­00268

One year study of syncope

Khin O. O. Lwin, Than Than Kyaing, Kyaw Soe Win, Khin Maung Win, Myint Ngwe, Hein Htet Aung

Department of Cardio Vascular Medicine, Mandalay General Hospital, Mandalay, Myanmar

Introduction:

Syncope is a common clinical presentation in clinical practice. And it is accounting for 1%‐­6% of hospital admission and up to 3% of emergency room visits. Syncope is one of the most challenging problems seen in medical practice.

Methods:

The aim of this study was to review the Clinical study and diagnostic evaluation of syncope patients who admitted to Department of Cardio vascular Medicine, Mandalay General Hospital. This study was one‐­year descriptive study, which included 144 syncope patients admitted to Department of cardio vascular Medicine, Mandalay General Hospital, from 1st May 2018 to 30th April 2019.

Result:

Syncope admission accounted 3.64% of total cardiac admission in one‐­year period. Mean age was 55.4 years (range 14‐­87 years). Out of 144 patients, 39.58% were males and 60.41% were females. The most common co morbidities in this study was hypertension followed by Diabetes and CAD. Out of 144 patients, cause of syncope could not be established in 27.08%. On evaluation with ECG, 62.5% (90) syncope patient had normal sinus rhythm in 12 Leads ECG on admission, remaining 37.5% (54) patients had high degree AV block‐­36, Atrial Fibrillation‐­10, Ventriculat Tachycardia‐­7 and SVT‐­1 respectively and 18 patients had significant ST‐­T changes noted . On 24 hours holter ECG monitoring was performed in 40 patients, 10 had paroxysmal Atrial Fibrillation and atrial flutter, 1 had paroxysmal SVT, 2 had non‐­ sustained VT, 2 had high PVCs load, 8 had significant sinus pauses with 17 had normal 24 hours holter ECG. Forty seven patients of explained syncope underwent Head Up Tilt Table Test, 44.6% (21) showed positive test and 55.3% (26) had negative test. In this study, twenty patients had structural heart diseases, 18‐­acute myocardial infarction and 2‐­severe mitral stenosis: they were treated as PCI and PTMC. Thirty eight patients were treated with PPM and one patient underwent CRT‐­D implantation.

Conclusion:

In this study 27.08% of patient could not be established causes of syncope. The weak point of this study was, in our center, we could not proceeded long term arrhythmia monitoring like event loop recorder or implantable loop recorder. The diagnostic yielded for on admission 12 leads ECG for syncope was 37.5% and 2D echo was investigation of choice for structural heart diseases.

AP19‐­00282

Long‐­term prognosis of Asian patients with short QT syndrome

Dae Young Kim, Jae‐Sun Uhm, Min Kim, Moo‐Nyun Jin, In‐Soo Kim, Hee Tae Yu, Tae‐Hoon Kim, Boyoung Joung, Hui‐Nam Pak, Moon‐Hyoung Lee

Severance hospital, South Korea

Introduction:

Short QT syndrome (SQTS) is a rare, life‐­threatening, inherited heart disease presenting as sudden cardiac death (SCD). The characteristics and prognosis of SQTS have not been known in Asian patients.

Methods:

We consecutively included patients who were diagnosed with SQTS in South Korea. STQS was defined as corrected QT interval ≤340 milliseconds in serial electrocardiograms. Patients without SQTS and overt cardiovascular disease were included by 1:4 age‐­ and sex‐­matching. Electrocardiogram characteristics and cardiovascular events were compared between patients with and without SQTS.

Result:

Thirty‐­four patients [age, 23.5 (21–30.5) years; male, 31] were followed up for 4.8 (2.0‐­7.7) years. In this SQTS cohort, young (<40 years) male were dominant. Symptoms included palpitation (n = 4, 11.8%), loss of consciousness (n = 3, 8.8%), and chest pain (n = 3, 8.8%). Early repolarization, tall T wave, J wave, and U wave were more frequent in patients with SQTS than the patients without SQTS. QT dispersion [44.0 (28.0–73.0) vs 20.0 milliseconds, P < 0.001] was significantly higher and heart rate [52.0 (17.0–58.0) vs 70.0 (62.0–84.0)/min, P = 0.001] was significantly slower in patients with SQTS than patients without SQTS. Atrial fibrillation (11.8% vs 2.9%, P = 0.030) and ventricular tachyarrhythmia (5.8% vs 0%, P = 0.005) were significantly more frequent in patients with SQTS than patients without SQTS.

Conclusion:

In Asian patients, SQTS is associated with atrial and ventricular arrhythmias.

AP19‐­00330

Sinus node dysfunction (SND) in an elderly patient with recurrent high‐­risk syncope diagnosed by electrophysiologic study (EPS)

Marie Barrientos, Rosemarie Ramirez‐Ragasa, Jerica Cristel Esguerra, Giselle Gervacio

Manila Doctors Hospital, Philippines

Introduction:

Syncope shares many clinical features with other disorders and presents with many differential diagnoses. Even more challenging is the evaluation of episodic loss of consciousness among elderly patients. One of the known causes of cardiac syncope is sinus node dysfunction (SND). Electrocardiography, telemetry monitoring, 24‐­hour Holter and implantable loop recorders (ILR) have been used to document and diagnose this condition. However, in our patient, whom SND was strongly suspected but no arrhythmia has ever been documented, electrophysiologic study (EPS) has provided the means in finally diagnosing the cause of his syncope.

Methods:

Case Presentation. We report the case of a 93‐­year old priest with recurrent episodes of high‐­risk syncope resulting in injuries and multiple admissions for the past 3 years due to fall. Repeated neurologic work‐­up and initial cardiac work‐­up results were all negative. Tilt‐­table testing was done to test for reflex syncope which showed systemic vasodilation on administration of isosorbide dinitrate (ISDN). Due to the recurrence of episodes and associated injury, the patient underwent EPS during his last admission which finally diagnosed SND.

Result:

Discussion. Early, rapid and intensive investigation is needed especially for patients with high risk features. These include syncope during exertion and no warning symptoms during attacks which the patient has. The sinus node recovery time (SNRT) in EPS is designed to test the automaticity of the sinus node during an electrophysiology study. The patient had prolonged SNRT and corrected SNRT during EPS which led to the diagnosis of SND.

Conclusion:

Though the patient was already positive for a vasodilator type of reflex syncope, a condition not usually requiring treatment, a high index of suspicion for an arrhythmic cause of the symptoms helped in finally diagnosing sinus node dysfunction and definitively addressed it with permanent pacemaker insertion.

AP19‐­00334

Progressive increase of conduction delay during premature stimulation in right ventricular outflow tract is related to ventricular fibrillation in Brugada syndrome

Yuki Hasegawa, Daisuke Izumi, Yasuhiro Ikami, Sou Otsuki, Nobue Yagihara, Kenichi Iijima, Akinori Sato, Tohru Minamino

Niigata, Japan

Introduction:

The local conduction delay has been deemed to play an important role in the occurrence and maintenance of ventricular fibrillation (VF) in Brugada syndrome (BrS). The purpose of this study is to evaluate the relationship between the local conduction delay during programmed stimulation and cardiac events in BrS patients.

Methods:

This study included 41 BrS patients who underwent electrophysiological study and implantation of a cardioverter defibrillator. We divided the patients into two groups based on whether they had experienced spontaneous VF events (11 patients) or not (30 patients). The local conduction delay was assessed using the interval between the stimulus and onset of the QRS complex (St‐­QRS) on the surface ECG lead V1 during programmed stimulation. To estimate a dynamic increase of conduction delay, the mean increase of delay (MID) was used (Figure). This parameter was calculated by dividing the integrated increase of delay in the conduction curve by the interval between the basic cycle length of 400 milliseconds and the effective refractory period (ERP) in right ventricular apex (RVA) and right ventricular outflow tract (RVOT).

Result:

MID during RVA pacing was similar in patients with VF (3.1 ± 1.1 milliseconds) than those without VF (2.2 ± 1.3 milliseconds) (P = 0.08). However, MID during RVOT pacing was significantly greater in patients with VF (4.2 ± 1.0 milliseconds) than those without VF (2.2 ± 1.0 milliseconds) (P < 0.01). ERP, inducibility of VF and electrocardiographic measurements including heart rate, PR interval, QRS duration, and QT interval were not different between two groups. There was no difference in clinical characteristics including age, sex, family history of cardiac sudden death, and the proportion of SCN5A mutation between two groups.

Conclusion:

MID during RVOT pacing was associated with VF in BrS patients and may be an additional electrocardiographic risk predictor for VF in BrS patients.

AP19‐­00346

Implantation of a permanent pacemaker in a patient with transposition of the great arteries and Mustard atrial baffle repair

Kantha Rao Narasamuloo, Iain Melton, Matthew Daly, Geoffrey Clare, Ian Crozier

Barts Health NHS Trust, United Kingdom

Introduction:

The atrial switch or baffle repair including the “Mustard” was the standard operative measure for TGA until the routine use of the arterial switch repair. They commonly cause atrial arrhythmias and sinus node dysfunction and baffle leaks and obstruction. Some patients require pacing, which presents unique anatomical issues which need to be understood for successful transvenous pacemaker implantation.

Methods:

N/A.

Result:

The patient is a 39‐­year‐­old male who underwent a Mustard operation at the age of 8 months. He had undergone electrophysiology study and ablation for incisional atrial flutter termination in 2012, and in 2013 he underwent transcatheter covered stent implantation for baffle leak. Currently presented with symptoms of non sustained atrial tachycardia and symptomatic sinus pauses. We choose to implant a dual chamber pacemaker from the left side via the cephalic vein. The active fixation ventricular lead was advanced via the systemic atria to the “anatomic left ventricle”. The atrial active fixation lead was advanced via the systemic atria to the remnant of the roof of the anatomic left atrium. (Diagram and figure chest X‐­ray PA and lateral)

Conclusion:

Here we will discuss the technique and steps required in pacemaker implantation in a patient who underwent Mustard repair for transposition of great arteries.

AP19‐­00368

Designing convolutional neural networks to predict sudden cardiac arrest

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:

Neural networks have not been designed to classify monophasic action potential (MAP) signals that could predict risk for sudden cardiac death or sudden cardiac arrest (SCA). The objective of this study was to develop and compare competing convolutional deep neural networks (CNN) trained on ventricular MAPs, which may alter with pathological remodeling from coronary disease (CAD) and left ventricular (LV) dysfunction, to predict SCA.

Methods:

In 26 patients with CAD and LV ejection fraction ≤40%, MAPs were recorded at 1 kHz in right (RV) and left (LV) ventricles at EP study. CNNs were iteratively developed in Keras (Python), trained to adjudicated, appropriate ICD therapy (labeled 0/1) at 752 ± 493 days. The network was trained and validated on 3580 MAPs (complete dataset).

Result:

Patients had age 62.0 ± 18.7 Y, LVEF 28.0 ± 8.3%. Figure A shows optimal final CNN with 3 convolutional (blue) and 2 recurrent (gray, ‘LSTM’) neural layers. Training was performed using k‐­cross validation (CV) with k = 7. Figure B shows that the CNN training accuracy of this design converged to

100%. In independent validation sets, CNN predicted SCA with accuracies up to 78% depending on clinical features of training and validation cohorts.

Conclusion:

We developed deep CNN which, using ventricular action potentials, may for the first time predict SCA at 2‐­3 year follow‐­up. These data form the basis for future studies of alternative learning models and additional electrophysiological features to predict SCA.

AP19‐­00378

Implantable cardioverter defibrillator for primary prevention in ischemic cardiomyopathy

Ami Isshiki, Makoto Suzuki, Karina Hara, Mari Ohmori, Ryo Tateishi, Toshio Kaneda, Takanobu Ozawa, Yosuke Yamakami, Hiroshi Shimada, Tomoko Mannno, Shigeki Kimura, Masato Shimizu, Hiroyuki Fujii, Mitsuhiro Nishizaki

Yokohama Minami Kyosai Hospital, Japan

Introduction:

Implantable cardioverter‐­defibrillator (ICD) is the standard of care for prevention of sudden cardiac death in high risk patients. However, in recent years complete revascularization has also been reported that the prognosis is good. We investigated the working status of patients who were diagnosed with ischemic cardiomyopathy at our hospital and who were implanted with ICD as primary prevention, and examined the predictors of lethal ventricular arrhythmia occurrence.

Methods:

Thirty‐­three consecutive patients who were given a diagnosis of ICM, and implanted with ICD for primary prevention from January 1994 to June 2018 were retrospectively studied. They were divided into 2 groups according to the occurrence of appropriate therapies during follow‐­up and their clinical variables and ECG parameters were compared.

Result:

After a median follow‐­up of 93 months, 10 patients (30%) had an event of appropriate discharges. No clinical variables could predict the events including age (66 years in the event group vs 64 in the no‐­event group), smoking status, presence of angina, organic coronary stenosis, left ventricular ejection fraction (36% vs 36%) and wall thickness, and prescription of β blockers (80% vs 84%). No patients showed No significant difference was found in QRS duration, and QTc interval. But significant difference was found in PQ interval (217 milliseconds vs 190 milliseconds P = 0.04).

Conclusion:

In ischemic cardiomyopathy with low left ventricular ejection fraction, the incidence of fatal arrhythmias was high and difficult to predict.

AP19‐­00430

Novel strategy for patients for patients who have high risk of sudden cardiac death and need pacing function ˜Dual device (the pacemaker and the S‐­ICD) management˜

Kei Mabuchi, Kanki Inoue, Hiroshi Fukunaga, Takahiko Nagase, Kohei Tanizaki, junichi Nitta, Mitsuaki Isobe

Sakakibara Heart Institute, Japan

Introduction:

Despite the widespread use of transvenous implantable cardioverter‐­defibrillators (TV‐­ ICDs) in clinical practice, concerns exist regarding ICD lead durability. Subcutaneous implantable cardioverter‐­defibrillator (S‐­ICD) has been available since February 2016 in Japan. In the real world, we have a dilemma that bradycardia pacing is required in patients with an indication for S‐­ICD. We investigated cases in which we underwent both S‐­ICD and pacemaker (PM) implantation in our institute. We evaluated safety and efficacy of the dual device.

Methods:

Between February 2016 and November 2018 in our institute, we retrospectively identified consecutive 55 patients received S‐­ICD. Of these patients, we analyzed 11 patients (20%) who was implanted not only S‐­ICD but also pacemaker.

Result:

The age of 11 patients was 49.6 ± 17.1 years old, and 83% of them were male. The most common reason of dual device management was breaking of shock lead of TV‐­ICD (6 cases, 55%). These 6 patients needed atrial pacing, so TV‐­ICD was downgraded to AAI‐­PM and atrial lead continued to be used. There were two cases in which PM became necessary after SICD implantation. In one case, leadless pacemaker was implanted. In the other case, DDD‐­PMI using myocardial electrodes was performed with tricuspid valve replacement. Both of them were carried out with a strategy that did not use transvenous lead. Sensing vector did not change post PMI. There was one case in which VF was detected after DDD‐­PMI, so SICD was selected because of post cardiac surgery. A rare case was concurrent implantation of VVI‐­pacemaker on the right side, and S‐­ICD on the left side for occupational reason and concerns about High‐­DFT of placing TV‐­ICD on the right side. As a valuable case, a transvenous shock lead placed subcutaneously at 6 years of age and followed for 10 years was switched to double‐­device consisting of a pacemaker with a myocardial electrode and S‐­ICD. These cases did not occur oversensing due to pacing pulse and interaction between S‐­ICD with DDD or VVI pacemaker. Inappropriate shock was occurred only one case for noise due to over sensing of myopotential. The problem was solved by changing another sensing vector.

Conclusion:

Dual device management is novel optional strategy for patients who require bradycardia pacing with an indication for S‐­ICD.

AP19‐­00467

Brugada syndrome

KHMAO Pichmanil, MAM Chandara

Calmette Hospital, Cambodia

Introduction:

Brugada syndrome (BrS) is an inherited cardiac disorder associated with an increased incidence of sudden cardiac death due to ventricular fibrillation in the absence of any structural heart disease, and it is characterized by coved ST segment elevation in the right precordial leads (V1V2V3). The prevalence of this disorder is still uncertain in the world but it has high incidence in Asia including Cambodia.

Methods:

Registration data from hospitalized and OPD department patients in both sexes including spontaneous type I ECG patter, symptomatic or asymptomatic patients with spontaneous type II and type III ECG, and resuscitated cardiac arrest without structural heart disease at Cardiology Department, Calmette Hospital.

Result:

The results are showed in diagrams.

Conclusion:

These series are the first study and showed that Brugada syndrome is not rare among Cambodian with predominantly in men around 40 years old. This study is one of the largest series of drug challenge by using oral Flecanide in making diagnostic of Brugada syndrome and showed that oral flecanide testing is an useful, inexpensive, safe and valid tool in the diagnostic strategy for the patients with spontaneous type 2 and type 3 ECG.

AP19‐­00560

An unusual case of pre‐­excitation and pre‐­syncope

Abhilash Sreevilasam Pushpangadhan, Mukund A Prabhu, Krishna Kumar Mohanan Nair, K. K. Narayanan Namboodiri, V. K. Ajit Kumar

Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala, India, India

Introduction:

A 24 year old girl presented with recurrent history of pre‐­syncopal episodes for last 10 years. Patient had no other cardiovascular symptoms. She had structurally normal heart by echo. Baseline ECG showed sinus rhythm with pre excitation suggestive of right postero‐­septal accessory pathway. A holter study done showed 2:1 AV block and intermittent CHB. CHB showed narrow QRS escape at 40‐­45 beats per minute. 1:1 broad QRS tachycardia at 130 beats per minute also noted during holter study. Three possibilities for this tachycardia were considered. (a) Sinus tachycardia conducting through accessory pathway (b) Atrial tachycardia conducting through accessory pathway (c) Atrio‐­ventricular re‐­ entry tachycardia (AVRT) with anterograde conduction via accessory pathway and retrograde AV node conduction despite CHB. (It is theoretically possible in supra‐­Hisian AV block) Considering all the possibilities, patient was taken up for an electrophysiology (EP) study to clear the confusion.

Methods:

Basal intervals Baseline ECG suggestive of manifest pre‐­excitation through right postero‐­ septal accessory pathway. Basal study showed AH 44 milliseconds, HV 24 milliseconds, SCL 900 milliseconds, earliest V during basal pre excitation recorded at CS proximal electrodes.

Result:

Retrograde study Incremental ventricular pacing showed VA dissociation at 700 milliseconds. This ruled out AVRT with anterograde conduction via accessory pathway. Anterograde study on incremental atrial pacing, pathway was getting blocked at 510 milliseconds. Programmed electrical stimulation from atrium revealed anterograde ERP of accessory pathway as 600:400 milliseconds. Atrial pacing at a cycle length of 320 milliseconds produced supra‐­Hisian complete heart block with narrow QRS escape rate of 45 beats per minute. Upon administration of atropine, anterograde conduction shifted to 3:2 pattern with beats getting conducted via AV node alone (narrow QRS) and AV node as well as via pathway (Pre excited QRS). Non conducted beats showed AH block. (See Figure 1). No tachycardia was induced during EP study.

Conclusion:

This young girl with history of pre‐­syncope for more than 10 years was found to have intermittent supra‐­Hisian complete heart block and modestly conducting right posteroseptal accessory pathway. Considering symptoms and intermittent CHB, she underwent dual chamber permanent pace maker implantation. Her tachycardia noted in Holter was assumed to be due to sinus tachycardia getting conducted through accessory pathway. Since the pathway was not conducting fast enough to produce a life threatening arrhythmia, pathway ablation was not done. Her pacemaker interrogation showed no high rate events up to one year of follow up now. Her pre‐­syncope disappeared after pace maker implantation.

FIGURE 1 EP study showing 3:2 AV conduction following atropine. First atrial beat is not conducted due to AH block. Second atrial beat conducted through AV node and producing a narrow complex QRS (Note HV interval of 42 ms). Third beat is conducted with pre‐­excitation. (HV interval <22ms)

AP19‐­00598

Successful transvenous lead extraction and upgrade to implantable cardioverter‐­defibrillator in a patient with subtype 2 short QT syndrome with ventricular fibrillation

Taiki Shiba, Yasunori Hiranuma, Sakuramaru Suzuki, Junya Harada, Kousei Tanaga, Toshihisa Inoue, Yoshitake Nakamura

Chiba Cerebral and Cardiovascular Center, Japan

Introduction:

Short QT syndrome (SQTS) is a inherited cardiac disease associated with atrial and ventricular arrhythmias leading to syncope and sudden cardiac death. Though there is limited data of SQTS, various device managements are sometimes required in patients with SQTS.

Methods:

We presented a case of 40 year‐­old‐­male diagnosed with subtype 2 SQTS.

Result:

He was admitted to our hospital because of out‐­of‐­hospital sudden cardiac arrest and survival. He was diagnosed with bradycardia atrial fibrillation in his childhood, VVI pacemaker was implanted at the 21‐­year‐­old because of cardiac arrest for 5 seconds. Genetic testing showed V141M KCNQ1 mutation and electrocardiogram revealed QTc interval was 330 milliseconds. He had a high probability of subtype 2 SQTS according to the diagnostic criteria proposed by Gollob et al. At the 40‐­year‐­old, he was found in witnessed out‐­of‐­hospital cardiopulmonary arrest. Bystander cardiopulmonary resuscitation was continued and one biphasic defibrillation for VF was performed by an automated external defibrillator. Then return of spontaneous circulation was achieved. Systemic inspections by multiple modalities showed there was no evidence of structural heart disease. We diagnosed with VF associated with subtype 2 SQTS. He had no neurological disability. An implantable cardioverter‐­defibrillator (ICD) was necessary for the purpose of secondary prevention of VF. Because venography revealed his right subclavian vein including the right ventricular lead was occluded totally, transvenous lead extraction and upgrade from the pacemaker to the ICD were performed at the same time. After transvenous lead extraction using Evolution® RL and dilator sheath, the extracted lead had heavy calcified and fibrous tissue. Finally ICD system was implanted successfully.

Conclusion:

In this case, various device management was necessary for bradycardia atrial fibrillation and VF in the patient with subtype 2 SQTS. In my best knowledge, this was a first case report that SQTS with V141M KCNQ1 mutation occurred VF.

AP19‐­00602

Evaluating the benefit of primary prevention ICD therapy in ischemic and non‐­ischemic cardiomyopathy patients from Asia, South America, Eastern Europe, and Africa: Sub‐­analysis from the improve SCA clinical study

Chi Keong Ching, Balbir Singh, Dejia Huang, Yen‐Bin Liu, Diego A. Rodriguez, Azlan Hussin, Young‐Hoon Kim, Alexandr Robertovich Chasnoits, K. H. Lin, Brian Van Dorn, Mark L. Brown, Daniel R. Lexcen, Shu Zhang

National Heart Centre Singapore, Singapore

Introduction:

Despite the burden of sudden cardiac death worldwide, implantable cardioverter defibrillators (ICDs) are underutilized, especially in Asia, Latin America, Eastern Europe, the Middle East, and Africa. The Improve SCA study demonstrated that primary prevention (PP) patients (pts) in these regions benefit from an ICD/CRT‐­D. One of the main study objectives was to determine whether there was a reduction in all‐­cause mortality among PP ICD recipients with one of the following risk criteria: syncope, NSVT, PVCs > 10/h, LVEF < 25%; all PP study patients with one or more of these criteria were categorized as 1.5 PP pts.

Methods:

The purpose of this sub‐­analysis was to evaluate the mortality benefit between implanted and non‐­implanted ischemic cardiomyopathy (ICM) and non‐­ischemic cardiomyopathy (NICM) pts categorized as 1.5 PP.

Result:

There were 1,361 1.5PP NICM pts, 790 (58.0%) of whom received devices; there were 387 1.5 PP ICM pts, 218 (56.3%) of whom received devices. Overall, there was a statistically significant 51% relative risk reduction in all‐­cause mortality among 1.5PP NICM pts. The mortality rate at 2 years for 1.5 PP NICM pts with or without an ICD/CRT‐­D was 11.7% and 19.4%, respectively. This equates to an NNT of 12.9. This mortality benefit was also observed in 1.5PP ICM pts, with a 48% reduction in all‐­ cause mortality among pts that received an ICD/CRT‐­D (Figure). The mortality rate at 2 years for 1.5 PP ICM pts with or without a device was 15.0% and 19.0%, respectively. This equates to an NNT of 24.9.

Conclusion:

In this large prospective evaluation of PP ICD pts, a 51% reduction in all‐­cause mortality was observed in 1.5 PP NICM pts and 48% reduction in all‐­cause mortality was observed in 1.5 PP ICM pts, which demonstrates a clear benefit to implanting ICDs in primary prevention pts with ischemic/non‐­ ischemic cardiomyopathy categorized as 1.5 PP.

AP19‐­00633

Patients characteristics of idiopathic ventricular fibrillation carrying SCN5A mutations without Brugada or long QT syndrome

Takanori Aizawa, Takeru Makiyama, Hai Huang, Tomohiko Imamura, JingShan Gao, Asami Kashiwa, Wuriyanghai Yimin, Hirohiko Kohjitani, Yuta Yamamoto, Seiko Ohno, Minoru Horie

Cardiovascular, Japan

Introduction:

The idiopathic ventricular fibrillation (IVF) is the main cause of sudden cardiac death (SCD) without any structural or metabolic heart disease, and some gene mutations are detected, which mainly code for ion channel units or its regulatory proteins. SCN5A mutations are one of the most common gene mutations in IVF patients as in Brugada syndrome (BrS) and long QT syndrome (LQT), but we can also detect the mutations in those who were not diagnosed as BrS and LQT. In this study, we evaluated the IVF patients’ characteristics with SCN5A mutations and without specific ECG pattern (Brugada like ST elevation and QT prolongation).

Methods:

From our database about gene testing, firstly, we extracted the 36 patients with SCN5A mutations, who documented spontaneous VF events. Then, we checked their ECG, and excluded BrS (spontaneous or induced coved type ST‐­elevation), LQT (QT prolongation), or other heart diseases. Then, we recruited 7 IVF patients and evaluated their characteristics and clinical history.

Result:

The median age was 19 years old (16, 16, 19, 38, 51, 60) and there were 6 males and 1 female. The genetic test about SCN5A mutations showed 5 pathogenic mutations (R433C, F1775LfsX15, R800H, Y68X, S329N) and 2 unknown pathogenic mutations (IVS21+17G>A, IVS7+5A>G). The detail of one female patient was not fully known. Three patients had the history of syncope events before IVF and only one male patient, who had received permanent pacemaker (PM) implantation for sick sinus syndrome, had familial history of IVF that his elder brother had the VF history and received implantable cardioverter defibrillator (ICD) therapy. Their other ECGs showed that one patient was only bradycardia, two patients had premature ventricular complex (one of two with couplet and another with inversion T wave in precordial leads), one patient with PM had atrial pacing rhythm and intraventricular conduction disturbance, and one patient showed complete right bundle branch block without ST elevation. Three patients underwent electrophysiology study, and only one of them could induced VF. The pilsicainide challenge test was important for excluding BrS, however, only 3 patients had undergone the test and all of their results were negative. As a treatment, all 7 patients received ICD and 2 patients took medical therapy.

Conclusion:

We evaluated the characteristic of patients undetected any obvious heart disease with SCN5A mutations, and most of them are male and young‐­onset without any familial history. More studies are needed to reveal this problem.

AP19‐­00644

The combination of T‐­Wave alternans and NT‐­ProBNP in predicting sudden cardiac death

Hoang Anh Tien

Hue University of Medicine and Pharmacy, Vietnam

Introduction:

Studies in recent decades have shown that T‐­Wave Alternans (TWA) was associated with ventricular arrhythmias due to stimulation and idiopathic ventricular arrhythmias. The clinical evidence proved TWA, N‐­terminal pro‐­B‐­type Natriuretic Peptide (NT‐­ProBNP) to be very reliable markers for the risk of sudden cardiac death (SCD). The combination of the two above predictive markers will promote the predictive value. Therefore, we carry out this study with three objectives: (a) Evaluate TWA in predicting sudden cardiac death (b) Evaluate NT‐­ProBNP in predicting sudden cardiac death; (c) Evaluate the combination of NT‐­ProBNP and TWA in predicting sudden cardiac death in myocardial infarction patients.

Methods:

This was a longitudinal study. Our subjects included 121 people divided into two groups. Disease group: 71 myocardial infarction patients admitted to the Cardiology department of Hue University of Medicine and Pharmacy Hospital, Vietnam from May 2017 to May 2019. Control group: 50 healthy people of the same range of age. Time of following: 24 months. TWA was analyzed continuously with the time‐­domain modified moving average method. NT‐­ProBNP was measured with ELISA (Enzyme‐­linked Immunosorbent assay) method.

Result:

The study was carried out in 71 myocardial infarction patients (32 males, 39 females), aged from 25 – 75. TWA of the control group was 31.38 ± 12.14 μV and the disease group was 97.54 ± 31.73 μV (P < 0.0001). The NT‐­ProBNP of the control group was 52.69 ± 25.46 pg/ml and the disease group was 2595.41 ± 952.15 pg/ml (P < 0.0001). (a) The best cut‐­off point of TWA in predicting sudden cardiac death was 107 µV; AUC = 0.81 (95% CI: 0.69‐­0.87); the sensitivity: 83.7 % (95% CI: 64.5‐­94.8); the specificity: 66.9 % (95% CI: 54.1‐­78.6). (b) The best cut‐­off point of NT‐­ProBNP in predicting sudden cardiac death was 3168 pg/ml; AUC = 0.86 (95% CI: 0.72‐­0.91); the sensitivity: 84.6 % (95% CI: 64.5‐­93.6); the specificity: 70.3 % (95% CI: 59.3‐­81.6). (c) TWA could predict sudden cardiac death with OR = 8.45 (P < 0.01); NT‐­ProBNP could predict sudden cardiac death with OR = 7.26 (P < 0.01); the combination of NT‐­ProBNP and TWA in predicting ventricular arrhythmia in myocardial infarction patients: OR = 17.91 (P < 0.001).

Conclusion:

The combination of NT‐­ProBNP and TWA provided a better value of predicting the sudden cardiac death in myocardial infarction patients, compared with NT‐­ProBNP or TWA alone.

AP19‐­00657

Pheochromocytoma masquerading long QT with T wave alternans and leading to subsequent syncope due to Torsades des pointes

Raghav Bansal

Holy Family Hospital, India

Introduction:

Long QT syndrome is an important cause of malignant arrhythmias leading to syncope and sudden cardiac death, especially in younger population. Being a genetic disease, it remains incurable and requires lifelong palliative treatment with beta blockers and implantable cardioverter defibrillators. T wave alternans in the presence of long QT syndrome is an ominous marker and warrants aggressive treatment. Pheochromocytoma mimicking long QT syndrome and leading to TDP has been rarely reported. However, to the best of our knowledge, this is the first case demonstrating long QT syndrome with T wave alternans secondary to pheochromocytoma.

Methods:

An 11‐­year‐­old boy, born out of consanguineous marriage, presented with recurrent episodes of palpitations, sweating and syncope related to exertion over a period of 1 month. A diagnosis of long QT syndrome with T wave alternans was made on baseline ECG. The child was immediately started on propranolol and cardiac sympathetic denervation was contemplated. There was no family history of sudden cardiac death. However, echocardiography surprisingly revealed gross left ventricular hypertrophy (LVH) with normal systolic function and without outflow tract obstruction. Cardiac MRI done to investigate LVH demonstrated concentric hypertrophy without any scar suggestive of secondary LVH. During the hospital stay, the child was noted to have episodic brief torsades des pointes (TDP) along with significant fluctuation of heart rate and blood pressure. A clinical suspicion of pheochromocytoma in view of LVH and fluctuant vitals, triggered further investigations. A raised urinary vanillylmandelic acid (VMA) and a 3.3 × 3.0 × 3.4 cm contrast enhancing mass arising from left adrenal gland clinched the diagnosis. Blood pressure control and QT interval improved after initiation of prazosin.

Result:

The child underwent laparoscopic excision of tumour after ruling out tumour metastasis on 68 Ga‐­DOTATATE PET‐­CT. Histopathological analysis of the specimen revealed tumour cells expressing synaptophysin, chromogranin and S‐­100 protein confirming the diagnosis of pheochromocytoma Post‐­surgery QT interval returned to normal and the child remained asymptomatic without any medications.

Conclusion:

The case illustrates possibility of pheochromocytoma being an important treatable secondary cause of long QT syndrome with T wave alternans and malignant ventricular arrhythmias. High index of suspicion, as in this case, holds the key for making the diagnosis and appropriate management.

FIGURE 1 Baseline ECG revealing prolonged QT interval with T wave alternans

FIGURE 2 ECG showing prolonged QT interval without T wave alternans

FIGURE 3 ECG monitor recording revealing brief episode of TDP triggered by an R on T ventricular premature complex

FIGURE 4 Baseline ECG demonstrating sudden change in sinus rate suggestive of paroxysms related to pheochromocytoma

FIGURE 5 Gross concentric LVH seen on Cardiac MRI

FIGURE 6 Gross appearance of the tumour mass after laparoscopic excision

FIGURE 7 Post‐­surgery ECG with normalization of QT interval

AP19‐­00696

Usefulness of cardiac magnetic resonance to predict sudden cardiac arrest in patients with mitral valve prolapse

Jaehyuk Lee, Jae‐Sun Uhm, Min Kim, In‐Soo Kim, Moo‐Nyun Jin, Young Joo Suh, Hee‐Tae Yu, Tae‐Hoon Kim, Yoo Jin Hong, Hye‐Jeong Lee, Chi Young Shim, Young Jin Kim, Boyoung Joung, Geu‐Ru Hong, Hui‐Nam Pak, Moon‐Hyoung Lee

Yonsei University College of Medicine, South Korea

Introduction:

Generally, Mitral valve prolapse (MVP) is regarded as a benign condition, but the association of MVP with ventricular arrhythmias (VA) and sudden cardiac arrest (SCA) has been recognized. The objective of the present study was to elucidate the predictors of SCA in patients with MVP.

Methods:

We retrospectively reviewed medical records of patients with MVP who underwent cardiac magnetic resonance (CMR). Patients with other structural heart disease were excluded. ECG (PR interval, QRS duration, QTc interval, bundle branch block, and atrial fibrillation), echocardiography (ejection fraction, mitral regurgitation grade, right ventricular systolic pressure, prolapsing mitral leaflet), CMR (left and right ventricular end‐­diastolic and diastolic volume, left atrial volume, mitral regurgitation volume, delayed enhancement, native T1 value) data were analyzed.

Result:

Seventy‐­six patients (age, 54.07 ± 16.3 years; 42 men) were included and among them, 11 patients (age, 45.8 ± 17.6 years; 9 men) experienced SCA or VA. In patients with SCA, delayed enhancement on CMR was significantly frequent than in patients without SCA (72.7% and 23.1%, respectively, P = 0.003). There were no significant differences in demographic, ECG, echocardiographic, and other CMR parameters between patients with and without SCA. Patients with delayed enhancement on CMR had significant risk of SCA (odds ratio, 6.28; 95% confidence interval, 1.46–33.93; P = 0.019).

Conclusion:

Delayed enhancement on CMR is risk factor of SCD in patients with MVP.

AP19‐­00751

A case report: Low dose Lacosamide caused transient complete atrioventricular block a patient with complete left bundle branch block

Hideomi Fujiwara, Nobuhiro Nishiyama, Masahiro Morise, Yuhei Isonaga, Chinatsu Komiyama, Mitsuhiko Ota, Yo Fujimoto, Takahide Kodama

Cardiology, Japan

Introduction:

Lacosamide (LCM) is a novel antiepileptic drug acting on voltage–dependent sodium channels in brain nerve. Some case reports have shown that high dose LCM (over 200 mg/day) induced Atrioventricular block (AVB) in especially elderly people. It is not well known effect on AV node of low dose LCM.

Methods:

A 71 years old man who had complete left bundle branch block (CLBBB) for over 10 years and brain metastasis from rectal cancer. He suffered from symptomatic epilepsy. He initiated low dose LCM (100 mg/day), and got anti‐­cancer drugs. On the 119th day after initiation of LCM, he went to ER with presyncope.

Result:

The electrocardiography showed complete AVB (CAVB). The level of Ccr was 37.24 ml/min, obviously decreased compared with 2 weeks ago. LCM is a renal excretion drug, we suspected drug induced CABV. We discontinued LCM immediately, AV conduction was recovered 12 hours after the last oral administration of LCM. After 2 months, his heart rhythm remains sinus rhythm without AVB.

Conclusion:

The permissible dose of LCM for the patients with renal dysfunction (Ccr < 30 mL/min) is up to maximum 300 mg/day. In this case, he developed CAVB in spite of low dose LCM administration. It is well known that sodium currents play a important role of cardiac conduction especially in Purkinje fibers. He had intraventricular conduction delay (CLBBB) for over 10 years, LCM might have worsened his remaining right bundle branch conduction. And also, there might be elevation of blood concentration of LCM due to rapidly progressed renal dysfunction. We report a case that low dose LCM caused transient CAVB in a 71 years old man with CLBBB and rapidly progressed rental dysfunction. This case report indicates that we need to use LCM carefully when the patient has intraventricular conduction delay, especially change in renal function.

AP19‐­00755

Application of QRS dispersion with surface electrocardiogram to identify the patients experiencing sudden cardiac death

Cheng‐I Wu

Taipei Veterans General Hospital, Taiwan

Introduction:

The available non‐­invasive electrocardiographic examination only provides weak predictive value for the risk of sudden cardiac death (SCD) in the structurally healthy heart population. To investigate the prognostic value of the QRS vectorcardiogram of the surface electrocardiogram (ECG) on the SCD risk stratification.

Methods:

This retrospective study enrolled 346 patients from January 2016 to December 2018. Patients with congenital heart disease or heart failure were excluded. 72 patients have experienced sudden cardiac death. All the SCD patients have cerebral performance category 1 or 2. The surface ECG was recorded during an electrophysiology stud, and inter‐­QRS descriptions were analyzed. The inter‐­ leads QRS dispersion, the percentage of the loop area (PL), and the loop dispersion were compared between groups.

Result:

A total of 315 patients (mean age of 51.9 ± 17.4 years old, 49.8% male) were analyzed. The basic demographic variables were comparative. In the model of multivariate analysis, coronary artery disease, PR interval, V4‐­5 dispersion, and PL could be the predictors for SCD. In subgroups analysis of SCD, CAD and the V3‐­4 dispersion could be used to predict the etiology of SCD.

Conclusion:

To the first time, the parameters of QRS loop descriptors of surface ECG precordial leads could be used as non‐­invasive markers to identify the patients experiencing SCD from the normal population. It could also be used to determine prognosis in subgroup analysis and determined possible etiology.

AP19‐­00758

Sinus node disease in young adult with Brugada type 1: Which one to treat?

Haikal Haikal

Binawaluya Cardiac Center, Indonesia

Introduction:

The coexistence of sinus node disease (SND) and Brugada syndrome (BS) raises diagnostic and therapeutic dilemmas in symptomatic subjects, particularly if SND is the initial diagnosis.

Methods:

A 40 years‐­old man came to our hospital with a chief complain of lightheadedness and palpitation since early 2017. He doesn't have history of sudden cardiac death on his family member. Electrocardiographic showed sinus rhythm with pronounced elevation of the J point, a coved‐­type ST segment, and an inverted T wave in V1 and V2. Coronary angiography revealed no significant stenosis of the coronary artery. Implantable loop recorder (ILR) was implanted and showed sinus pause for more than 7 seconds, paroxysmal atrial fibrillation and non‐­sustained monomorphic ventricular tachycardia (VT) without clear symptom related. Implantation of dual chamber pacemaker was chosen rather than ICD in this patient with careful observation at an outpatient clinic.

Result:

There has been not sufficient clinical evidence whether SND or SSS is a risk factor for future ventricular arrhythmic events in BS. Implantation of an ICD is only first‐­line therapy for symptomatic BS

Conclusion:

There has been not sufficient clinical evidence whether SND or SSS is a risk factor for future ventricular arrhythmic events in BS. Implantation of an ICD is only first‐­line therapy for symptomatic BS.

Keywords: Sinus node disease, brugada syndrome type I, young adult

AP19‐­00778

Clinical and genetic features of long QT syndrome in Korean population

Jue Seong Lee, Jong‐Il Choi, Young Ran Jeon, Yun Gi Kim, Suk‐Kyu Oh, Ki Yung Boo, Do young Kim, Jaemin Shim, Young‐Hoon Kim

Korea University Anam Hospital , South Korea

Introduction:

Long QT syndrome is an inherited cardiac disease caused by abnormalities in cardiac ion channel. Untreated, symptomatic patients have a high mortality rate, with a mortality rate of 21% within 1 year of symptom onset. The aim of this study is to investigate the characteristics of LQTS in Korean population.

Methods:

We studied the updated medical records from last year's data with confirmed LQTS from Korean Inherited Arrhythmia Registry and Korea University Hospital from January 2013 to June 2019.

Result:

Total 61 LQTS patients were enrolled. The number of female patients was more prevalent with 48 patients (78.6%). Median age of diagnosis was 35.7 ± 17 years old. Aborted cardiac arrest was the most common symptom at the time of diagnosis (30 patients, 49.1%), followed by presyncope or syncope (16 patients, 26.2%). Twelve patients had no symptoms at the time of diagnosis (19.6%). And total 57 patients had experienced syncope at least once (93.4%). Ventricular fibrillation was documented in 21 patients (34.4%) and ventricular tachycardia was documented in 13 patients (21.3%). Epinephrine test was performed in 18 patients, and 12 patients of them had positive result (66.7%). Mean corrected QT interval was 505.4 ± 58.5 milliseconds. QTc longer than 480 milliseconds was 39 patients (63.9%) and The proportion of QTc ≥ 480 milliseconds was higher in female patients (P = 0.03) Unexplained sudden cardiac death (SCD) under 30 years of age among family members was found in 6 patients (9%) and under 50 years was found in 8 patients (13%). There were 47 patients (77%) taking beta‐­blocker and implantable cardioverter defibrillators were applied to 38 patients (62.3%). Genetic testing was done in 43 patients. 17 patients were confirmed genetic mutations (KCNQ1 6 patients, KCNH2 5 patients, SCN5A 4 patients, others 4 patients).

Conclusion:

In Korean LQTS patients, most patients experienced syncope and nearly half of the confirmed LQTS patients (49.1%) were experienced cardiac arrest at the time of diagnosis. The diagnostic yield of major LQTS gene mutations were not higher than previously reported.

AP19‐­00787

Heterogeneity of electrocardiogram features in sudden cardiac death (SCD) patients along 24 hours

Yangxin Chen, Huiying Zhao, Wenhao Liu, Yuling Zhang, Jingfeng Wang

Department of Cardiology, Sun Yat‐­sen Memorial Hospital, Sun Yat‐­sen University, GuangZhou, GuangDong, China

Introduction:

Sudden cardiac death (SCD) is often the result of a sudden loss of blood flow caused by the failure of the heart to effectively pump. To prevent SCD, early prediction of SCD risk is essential. Utilization of electrocardiogram (ECG) markers to predict SCD has a long history. However, no study has been performed to discover the ECG features of SCD patients in different time regions by using 24‐­hours ECG data.

Methods:

In this study, we collected 24 hours ECG data of 24 sudden cardiac death (SCD) samples, 42 high‐­risk SCD patients and 43 healthy controls. The samples were divided into training and the independent test datasets. In the training dataset, 24 SCD patients and 30 healthy controls were selected, and the remained 39 high‐­risk patients and eight healthy controls were used for independent test. The ECG data were divided into multiple fragments, and each fragment is one minute long. Within each ECG fragment, LASSO was used to build regression models in the training dataset by 5‐­fold cross validation. Finally, we used greedy searching method to construct a combine model.

Result:

The 24‐­hours ECG data of individual was divided into 1440 time fragments. After the filtering, 925 time fragments were remained. In each time fragment, we compared 28 ECG features in the SCD patients and the controls by student's t‐­test, which discovered 13 features significantly different between them. The performance of the individual feature in discriminating SCD patients and controls along 24 hours were examined, which showed that wave duration related features and the R wave area performed the best in 8:00‐12:00 am, and the S wave area related features achieved the best performance in 2:00‐4:00 am. Integrating multiple features in each time fragment by the LASSO regression demonstrated area under the receiver operating characteristic curves (AUC) within 8:00‐­12:00 am provided the best AUCs. The same conclusion was obtained by the independent tests. By connecting the models within 8:00‐12:00 am, a unique model was constructed using greedy searching method, which achieved ACC 0.95 in five‐­fold cross validation test.

Conclusion:

This study discovered the S and R wave areas as potential features to significantly discriminate the SCD patients with the controls in 2:00‐­4:00 am and 8:00‐­12:00 am, respectively. A reliable combined model was constructed by integrating multiple ECG features obtained in 8:00‐­12:00 am.

AP19‐­00833

A case of torsades de pointes storm caused by various factors of QT prolongation

Yuki Kimura, Hidemori Hayashi, Hiroki Matsumoto, Haruna Tabuchi, Gaku Sekita, Masataka Sumiyoshi, Yuji Nakazato

Juntendo University Hospital, Japan

Introduction:

Torsades de pointes (TdP) is a devastating form of polymorphic ventricular arrhythmia associated with QT interval prolongation. Several risk factors of prolonged QT interval have been identified such as female gender, advanced age, hypothyroidism, electrolyte imbalance, cardiac abnormalities, and use of QT prolonging drugs as the most frequent cause.

Methods:

We present a case of TdP storm caused by various factors of QT interval prolongation.

Result:

A 20‐­year‐­old female presented with convulsive syncope during sleep. Her past medical history was significant for recurrent faintness since her school‐­days. One year ago, she lost consciousness with her eyes rolled back at night. However, she had never been examined in the hospital because she recovered spontaneously. In this presentation, she lost consciousness again a week after garenoxacin was prescribed for an upper respiratory infection. In the emergency department, she was disoriented but her vital signs were stable and. There were no abnormal finding of her laboratory data and an CT scan of the brain. An ECG demonstrated sinus rhythm with markedly prolongation of QT interval (QTc 0.63 milliseconds) and frequent episode of TdP was developed just after admission. Finally, she was required an emergency intubation and electrical defibrillation was attempted repeatedly for electrical storm of TdP. Although Magnesium sulfate was ineffective for TdP storm, combination of lidocaine and landiolol eliminated TdP eventually. Follow‐­up ECG showed T wave inversion in the inferior and precordial leads. Echocardiogram showed apical wall abnormalities (ballooning), therefore Takotsubo cardiomyopathy was suspected. In addition, serum calcium was 7.4 mg/dL due to pseudo hypoparathyroidism. Cardiac function recovered in two weeks, but QT interval prolongation remained (QTc 0.46 seconds). She has been free of syncope taking an oral beta blocker with bisoprolol 2.5 mg once a day over a 6‐­month follow up.

Conclusion:

In conclusion, we report a case of electrical storm of TdP following marked QT interval prolongation by antibiotics, electrolyte abnormality, and Takotsubo syndrome, in a patient suspected for congenital long QT syndrome.

AP19‐­00858

Prevalence of brugada syndrome in 2 heart centres in Malaysia; our current data

Ahmad shukri Saad, Ahmad faiz Mohd ezanee, Ru Hoi Tan, Ummu Atiqah Noorazmi, Yi Zhi Cheng, Joel Matthews; Izzatul, Nadzirah Ismail; Chew, Wei Leong, Kantha Rao Narasamuloo, Sathvinder Singh Gian Singh, Hazleena Mohamed Hasnan, Hidayatil Alimi Keya Nordin, Dharmaraj Karthikesan, Ahmad Suhaimi Mustafa, Siti Hajar Mohd Khirrudin, Saravanan Krishnan

Hospital Sultanah Bahiyah, Malaysia, Malaysia

Introduction:

Brugada syndrome carries a devastating outcome. We aimed to establish the prevalence of brugada sign by ECG criteria (type I, 2 & 3) & syndrome at 2 heart centres; Hospital Sultanah Bahiyah Heart centre & Queen Elizebeth II Hospital, Sabah Heart centre.

Methods:

Patient presented with ECG changes fulfilling criteria of brugada type I, 2 & 3 were included in the study beginning 5th September 2017 until 23rd June 2019.

Result:

Total of 35 patients met the inclusion criteria (mean age 42.1, 97.2% male). The 12‐­lead ECGs of these patients were reviewed and clinical information was recorded. There were 14 patients with type 1 ECG (40%), 17 patients with type 2 ECG (48.57%) & 4 with type 3 ECG (11.43%). Only 6 consented for provocation test; 5 use flecanide & 1 uses ajmaline as agent respectively. There were 4 positive provocation tests; all uses flecanide & all subsequently undergone ICD implantation.

Conclusion:

Our data may not reflect true prevalence of brugada syndrome in Malaysia. National Multicentre collaboration will give elicit better picture of true prevalence.

AP19‐­00864

Case report of ventricular septal hypertrophic cardiomyopathy and left ventricular non‐­ compaction carrying OBSCN and FHOD3 gene mutations

Yulong Xia, Jing Zhou, Kang Li, Qinhui Sheng, Wenhui Ding, Yansheng Ding, Jie Jiang

Peking University First Hospital, China

Introduction:

A 19‐­year‐­old male was admitted to our hospital because of syncope. He denied any history of hypertension and diabetes. A little brother of his died of suspicious cardiac causes at 3 months old of age and other family members are healthy. He underwent multiple electrophysiology studies (EPS) since 4 months of age, during which he was diagnosed with pre‐­excitation syndrome with multiple atrioventricular accessory pathways and dual atrioventricular nodal pathways, which was all successfully treated by ablation. Meanwhile, echocardiogram showed “symmetrical hypertrophic cardiomyopathy and normal ejection fraction”. He stopped regular follow‐­ups 5 years ago because there were no more symptoms. Activity‐­related palpitations occurred again and then developed syncope during running. EKG showed wide QRS tachycardia (Figures 1 & 2).

Methods:

By using cardiac imaging tools, genetic sequencing methods and EP study, we define the diagnosis of this young patient.

Result:

EPS showed fasciculo‐­ventricular pathways which were inconsistent with the wide QRS tachycardia and dual atrioventricular nodal pathways which failed to induce tachycardia, therefore he didn't undergo ablation. In hospital cTNI and CK‐­MB was elevated. Echocardiogram (Figures 3, 4 & 5) showed an enlarged left ventricle, severely reduced left ventricular ejection fraction, and unsymmetrical septal hypertrophy and left ventricular non‐­compaction (LVNC), while the so‐­called symmetrical left ventricular posterior wall hypertrophy turned out to be LVNC. Besides the echo manifestations, Cardiac magnetic resonance showed a decrease perfusion of left ventricular middle layer myocardium, and late gadolinium enhancement of left ventricular middle layer and subepicardial myocardium. Genetic testing showed he was a carrier of variants p.Val5836Met of the OBSCN gene and variants p.Met1212Thr of the Formin Homology 2 Domain Containing 3 (FHOD3) gene. Family genetic sequencing showed his father and old sister were both carriers of these two variants while his mother wasn't, but all their echos and EKGs were normal. In summary, ventricular septal HCM and LVNC was diagnosed. We prescribed him sacubitril valsartan, bisoprolol and spironolactone to treat heart failure and warfarin to prevent thromboembolic events. Since there were no pacing indications, subcutaneously ICD was implanted to prevent SCD (Figure 6). Now he is on follow‐­ups and has no syncope episodes, thromboembolic events and heart failure symptoms.

Conclusion:

LVNC is easily misdiagnosed as HCM and we should carefully use cardiac imaging tools to differentiate. It can be combined with other cardiomyopathies such as HCM/DCM. In our case, LVNC and septal HCM are presented in one patient and his symptoms were mainly arrhythmia‐­related. And we identified a novel gene mutation of the FHOD3 gene in his family which needs more evidence in future studies.

AP19‐­00882

Histamine‐­2 receptor antagonist induced malignant arrhythmia in long QT syndrome patient

Adrianus Akbar, Doni Friadi, Gugun Iskandar Hadiyat

Hasna Medika Cardiovascular Hospital, Indonesia

Introduction:

Long QT syndrome (LQTS) is a cardiac disorder caused by abnormally prolonged ventricular repolarization due to defects in cardiac sodium and potassium channels. It is characterized by prolongation of the QT interval in an electrocardiogram (ECG), and has the propensity to develop torsades de pointes (TdP) or ventricular tachycardia (VT) which frequently leads to syncope or cardiac arrest.

Methods:

–

Result:

A 30 year old woman was referred to our emergency department after having two short‐­lasting episodes of unconsciousness and apnea which were witnessed by family member. Local clinic ECG recording showed a non‐­sustained polymorphic VT. She claimed to have experienced these complaints after ingesting ranitidine syrup the previous day. On arrival, she was awake but pale and had several episodes of non‐­sustained polymorphic VT. Intravenous magnesium sulfate was administrated and non‐­ sustained polymorphic VT was stopped. ECG showed prolonged corrected QT interval with 653 msec after conversion to sinus. The diagnosis was established by using Schwartz score which showed high probability of LQTS. Laboratory investigation showed normal electrolyte levels except for a slight hypocalcemia which was corrected. Genetic laboratory test could not be done because it was not covered by the governmental insurance. She had a prior family history of sudden cardiac death. Propranolol 20 mg three times daily was given at the time of her discharge from the hospital. After a 2 month outpatient clinic follow up, her ECG showed shortening of corrected QT interval. Since then, she has been well with no subsequent recurrence of the problem.

Conclusion:

Analyzing the ECG and calculating corrected QT interval still remain relevant as one of the mainstay diagnostic tool. Acute treatment with intravenous magnesium sulfate in patient with recurrent non‐­sustained polymorphic VT successfully converted the rhythm into sinus. Several histamie‐­2 receptor antagonist has been linked to cause arrhythmia, however to our knowledge, there has been no previous report about ranitidine inducing arrhythmia in LQTS. Beta blocker (propranolol) is effective in shortening QT interval for this patient.

FIGURE 1 ECG before magnesium sulfate was administered

FIGURE 2 ECG after magnesium sulfate was administered intravenously

FIGURE 3 ECG taken at the outpatient clinic follow up

AP19‐­00916

Evolving J‐­wave electrocardiographic pattern precipitating polymorphic ventricular tachycardia in a patient with probable silent coronary artery spasm

Michael Chi Yuan Nam, Anna Kefala, Pradeep Wijayagoonawardana, John Paisey, Waqas Ullah, Paul Roberts, Arthur Yue

Bournemouth Hospital ‐­ UK, United Kingdom

Introduction:

N/A

Methods:

N/A

Result:

N/A

Conclusion:

N/A

FIGURE 1 Admission electrocardiogram showing sinus rhythm and inferolateral ST‐­segment depression

FIGURE 2 Dynamic J‐­point elevation prior to ventricular tachycardia and ICD discharge. Electrocardiograms captures on continuous cardiac monitoring whilst inpatient. Corresponding times on bottom of each trace

FIGURE 3 Electrograms at baseline and during right coronary artery contrast injection. Notice loss of S wave most noticeable in lead III, QRS broadening, and J‐­point elevation

AP19‐­00968

Evidence based case report: Pseudo‐­Brugada pattern may predict sudden cardiac death in hyperkalemia

Alexander Edo Tondas, Raymond Pranata, Rolando Agustian Halim

Mohammad Hoesin General Hospital, Indonesia

Introduction:

The “pseudo‐­Brugada” pattern or also known as “Brugada Phenocopy”, is a term used to describe clinical entities that are etiologically distinct from true congenital Brugada syndrome.

Methods:

In this report, we described a patient with hyperkalemia who showed the Brugada pattern without any other ECG features of hyperkalemia and how the patient deteriorated.

Result:

A 30 year‐­old female, P4A1 post caesarean section due to HELLP syndrome and impending eclampsia, was consulted to cardiology department with sudden onset of dyspnea, fever, but no chest pain. Past medical history was unremarkable. Family history was negative for sudden cardiac death of cardiac problem. Physical examination showed vitals of blood pressure of 170/100 mmHg, heart rate at 94 times/minute, respiratory rate at 32 times/minute, and SpO2 at 87%. Lung examination findings were rales on both sides consistent with pulmonary edema. Lab data showed initial potassium of 7.1 mEq/L, Hb: 10.2, WBC 29.500/mm3, platelet count 257.000/mm3, LDH 905 U/L, ureum 306 mg/dL, creatinine 9.2 mg/dL, natrium 124 mEq/L, ALT 39 mg/dL, AST 35 mg/dL and troponin T of 255 ng/dL. Her ECG was consistent with type 1 Brugada pattern (Figure 1). Her initial ECG when she was first admitted to the ED 5 days before the consult can be seen in Figure 2. Bedside echo suggested LVEF of > 55% with no regional wall abnormality. After administration of intravenous calcium gluconate, intravenous bolus of D40 and short‐­acting insulin aspart, 7 hours later, the patient potassium reduced to 6.31 meq/L and repeated ECG was ordered (Figure 3) showing diminished Brugada pattern. The patient was scheduled for immediate hemodialysis, but she was experiencing sudden cardiac death in the operating room before catheter double lumen placement. After reviewing some literatures, there were 77 cases reported with Brugada phenocopy pattern as the presenting ECG change, published within 1956 until 2018. On his publication, Littman et al published that over 10‐­year period research on his institution, only 9 cases were found by the authors that is fulfilled the criteria of Brugada phenocopy type 1 pattern. This poor patient outcome is actually consistent with what earlier described on a similar study. Littman et al described that patients with hyperkalemic Brugada phenocopy sign had a grave prognosis. His study showed that 5 of the 9 patients died within 48 hours after the ECG pattern recorded. Postema et al. mentioned that in patients who demonstrated Brugada ECG pattern with hyperkalemia, there's increased risk for the occurence of ventricular tachyarrhytmia/asystole, due to altered excitability of the heart, albeit different pathophysiology from true BrS.

Conclusion:

Although transient and reversible, the occurence of pseudo‐­Brugada or Brugada phenoscopy in hyperkalemic setting may become a predictor of fatality.

AP19‐­00973

Clinical usefulness of genetic testing in Asian patients with inherited arrhythmia syndrome

Joo Hee Jeong, Jong Il Choi, Young Ran Jeon, Su Bin Lim, Ha Young Choi, Yoon Young Choi, Ki Young Bu, Do Young Kim, Suk Kyu Oh, Yoon Ki Kim, Kwang No Lee, Jae Min Shim, Jin Suk Kim, Young Hoon Kim

Korean University of Medical College, South Korea

Introduction:

Genetic testing is used to diagnose inherited arrhythmias, without structural heart disease, that predispose to sudden cardiac death. We aimed to investigate the genetic features of patients with inherited arrhythmia syndrome using genetic testing in real‐­world clinical practice.

Methods:

This was a prospective, single‐­center study in South Korea. Total consecutive 66 patients who experienced sudden cardiac death who encountered with ventricular fibrillation or ventricular tachycardia without overt heart disease were enrolled, and tested Next Generation Sequencing (NGS) panel. If clinically significant genetic variants were found, familial screening with targeted genetic testing was encouraged to identify familial genetic inheritance and its clinical relevance.

Result:

Among the patients, 11 (16.7%) were diagnosed with Brugada syndrome, 11 (16.7%) were long QT syndrome, and 10 patients were idiopathic VF (15.1%). Other 34 patients had sudden cardiac death events and were suspected to have primary genetic arrhythmia syndrome, but did not fulfill the diagnostic criteria. Of 11 Brugada syndrome patients, 8 patients had genetic variants and 4 of them showed SCN5A variant (36.4%), which was higher compared to Caucasian data for diagnostic yield (20‐­25%). Other than SCN5A, variants were found in CACNB2, PKP2, SCN3B, TMEM) Seven of 11 patients (63.6%) with long QT syndrome were detected to have genetic variant (2 patients with KCNQ1, 1 patients with KCNH2 , 1 patient with SCN5A). Of 10 idiopathic VF patients, 8 patients were found to have variant, (KCNQ1, SCN5A, RYR2, etc). Of all patients, 39 patients (59.1%) were detected with gene mutation. Among the 39 patients with documented gene mutation, Brugada syndrome patients showed higher prevalence of SCN5A mutation than other disease entity (P = 0.012), corresponding with fact that SCN5A is a key gene mutation in Brugada syndrome. Cascade screening in 13 families were done. Familial screening did not show distinct gene mutation (P = 0.724). Of 13 cases, 5 cases were found to have same variant (38.5%). Only 1 case was diagnosed with Brugada syndrome, showing type 1 Brugada EKG. None of the family experienced sudden cardiac death.

Conclusion:

This study showed that NGS‐­based genetic testing improved the diagnostic yield of inherited cardiac arrhythmias in Asian, suggesting it may be helpful to lead therapeutic implication as well as clinically useful to confirm the diagnosis.

AP19‐­00980

First episode of ventricular fibrillation in 84‐­years old male with long QT 2 syndrome: A case report

Tomonori Miki, Keitaro Senoo, Takashi Okura, Hirokazu Shiraishi, Takeshi Shirayama, Satoaki Matoba

Kyoto Prefectural University of Medicine, Japan

Introduction:

Congenital long QT syndrome (LQTS) is known as a disease that can lead to ventricular arrhythmias and an increased risk of sudden cardiac death in young people, but extremely rare in elderly people to occur ventricular fibrillation (VF) as a first episode. We experienced a case of an elderly male with a first episode of loss of consciousness owing to torsades de points (Tdp).

Methods:

None.

Result:

An 84‐­year‐­old‐­man presented with syncope after urination. His medical history was hypertension and asthma, but no history of syncope ever. His electrocardiogram in 2017 showed a slight QT prolongation (QTc = 505 milliseconds). After the hospitalization, no medication inducing QT prolongation, no blood test showing electrolyte abnormalities, and no abnormal findings in echocardiography were found. He had then a loss of consciousness again during the hospitalization, and electrocardiogram caught incessant Tdp, which was caused by R on T with short‐­long‐­short (SLS) sequences due to sick sinus syndrome (heart rate = 50 bpm, QTc = 596 milliseconds). Coronary angiogram could not detect any myocardial ischemia, and therefore intracardiac defibrillator (ICD) was implanted for secondary prevention. QT duration was measured after ICD implantation by every 10 beats/minutes between 40 beats/minutes and 110 beats/minutes, and QT/RR slope was calculated 0.23. The genetic testing revealed KCNH2 gene mutation (LQTS type2).

Conclusion:

In this case, prolonged QT time revealed with aging and SLS sequences due to sick sinus syndrome triggered VF as a first attack in an older patient with LQT2 syndrome.

AP19‐­01014

A new definition of significant pauses

Ricardo Sadashi Mishima, Varun Malik, Kadhim Kadhim, Adrian Elliott, Dione Jones, Dominik Linz, Rajiv Mahajan, Dennis Lau, Prashanthan Sanders

University of Adelaide ‐­ Royal Adelaide Hospital, Australia

Introduction:

Cardiac pacing is indicated in patients with symptomatic asystolic pauses. However, the incidence of asymptomatic pauses as well as the incidence of syncope without concurrent pauses are unknown. The aim of this study is to describe the incidence and extent of asymptomatic pauses during daytime, as well as the incidence of syncope without concurrent pauses in patients with continuous heart rate monitoring over a prolonged follow‐­up period.

Methods:

Consecutive patients with an implantable loop recorder (ILR) device and detailed symptom and syncope log‐­book were studied. The electrograms were analysed and pauses due to undersensing were excluded. In addition, pauses occurring during night (between 10 pm and 6am) were also excluded.

Result:

A total of 639 patients with ILRs implanted between April 2011 and April 2019 were screened. After exclusion due to lack of follow up and/or data and age <18 years old, 516 patients were analysed. The mean follow‐­up period was 786.2 ± 418 days. Throughout this period, 78 patients had diurnal pauses out of which 26 had at least one episode of syncope or presyncope associated with a pause. The total number of diurnal pauses recorded was 242. In addition, 37 episodes of syncope and 119 episodes of presyncope were reported. The incidence of both syncope and presyncope was significantly higher in those with diurnal pauses. However, only 5 episodes of syncope and 36 episodes of presyncope were associated with a diurnal pause while in 32 syncopal events and 13 presyncopal events normal sinus rhythm was the underlying rhythm. Syncopal and presyncopal pauses were significantly longer than asymptomatic pauses (P < 0.001). The difference was not significant between syncopal and presyncopal pauses (P = 0.27). Duration was not significantly different across pause type (P for trend = 0.07). The proportion of symptomatic pauses in accordance with pause type was not statistically significant. After adjustment pause duration and ILR implanted due to syncope or presyncope were the strongest predictors of symptoms associated with a ventricular pause, whereas male gender was protective.

Conclusion:

While syncope and presyncope are more frequent among those with diurnal pauses, the vast majority of these episodes are not due to a pause. I addition, pauses shorter than 4 seconds are rarely associated with presyncope and syncope only occurred with pauses longer than 4 seconds.

AP19‐­01017

Association leisure time physical activity with risk of primary cardiac arrest in the general population: a nationwide cohort study of the dose‐­response relationship

Moo‐Nyun Jin, Pil‐Sung Yang, Hee Tae Yu, Tae‐Hoon Kim, Jae‐Sun Uhm, Jung‐Hoon Sung, Hui‐Nam Pak, Moon‐Hyoung Lee, Boyoung Joung

Yonsei University College of Medicine, South Korea

Introduction:

It is widely accepted that leisure time physical activity is associated with a reduced risk of mortality. However, high‐­intensity activity may transiently increase the risk of primary cardiac arrest (PCA). It is an important question from the public health perspective whether leisure time physical activity confers overall protection from PCA.

Methods:

In this nationwide sample cohort study, 506,805 individuals (mean age, 47.8 ± 14.4 years; 252,153 women [49.8%]) participated in the Korean National Health Screening Program. On the basis of level of leisure time physical activity (LTPA) indicated in a standardized self‐­reported questionnaire at baseline, we evaluated the effect of LTPA at different energy expenditures on the PCA.

Result:

During a median follow‐­up of 4 years, 799 PCA events were occurred, and the incidence of PCA was 41.1 events per 100 000 person‐­year. Compared with inactive individuals, those who met the minimum recommended physical activity level (7.5‐­15.0 metabolic equivalent hours per week) had a 36% lower risk of PCA (HR.0.64 [95% CI, 0.53‐­0.77]) and those who reported 2 to 3 times the recommended LTPA had the maximum benefit for reduced risk of PCA (HR.0.58 [95% CI, 0.44‐­0.76]). The continued benefits were observed up to 5 times the minimum recommended LTPA. In addition, there was no evidence of increased risk of PCA when more than 5 times the minimum recommended level (HR 0.74 [95%CI, 0.50‐­1.093]). These associations were consistent regardless of age, sex, BMI and across categories of Framingham risk score.

Conclusion:

The beneficial effect of LTPA on PCA started at al low dose and meeting the public health guidelines recommended minimum physical activity was associated with nearly the maximum risk reduction of PCA. The largest benefit occurred at 2‐­3 times the minimum recommended LTPA. Highly active level of up to 5 times the minimum recommended LTPA continued to have benefit against PCA and no excess risk at 5 or more time the recommended. In regard to PCA, health professionals should encourage inactive adults to perform LTPA and do not need to discourage adults who already participate in high level of LTPA.

AP19‐­01038

New onset high percentage ventricular pacing in implantable cardioverter defibrillator patient: Prevalence, predictors and effect on survival

Ruohan Chen, Keping Chen, Wei Hua, Xiaoqing Ren, Yan Dai, Shu Zhang

FuWai hospital, China

Introduction:

The prevalence, predictors of new onset high percentage ventricular pacing in implantable cardioverter defibrillator (ICD) patients are not well studied.

Methods:

This was a retrospective study enrolling 213 consecutive patients implanted with a home‐­ monitor ICD from 2010 to 2017 with a mean follow‐­up of 3.1 ± 1.9 years. After excluding patients with pacing indication, 182 patients were left in the study. The information of pacing percentage was exacted from home‐­monitor database. Ventricular pacing (Vp) ≥ 40% was defined as high Vp%, and Vp ≥ 80% pacing dependent (PD). The combined end point events included all‐­cause death, heart transplantation and device upgrade. The patients were assessed six months after implantation and every year thereafter. Multivariate logistic regression and Cox proportional hazard models were used for analysis.

Result:

The mean age was 55.9 ± 14.3 years; and male was 77.5%, with 30.8% primary prevention. New onset high Vp% occurred in 50 (27.4%) patients, after a mean time of 1.6 ± 1.3 years; PD developed in 21(11.5%)patients, and the mean time to PD was 2.7 ± 1.2 years. High Vp% was associated with a 2.79‐­time risk for end point events (95% confidence interval 1.45‐­5.39, P < 0.001). Older age, low ejection fraction and low basic heart rate were the strongest predictors of the high Vp%.

Conclusion:

In conclusion, new onset high Vp% was not uncommon in ICD patients and was related to decreased survival.

FIGURE 1 The trend of pacing percentage in different groups (Vp≥40% vs. <40%)

FIGURE 2 Kaplan–Meier estimates of cumulative incidence of endpoint

Table 1 Baseline characteristics vs admission Vp ≥ 40%

Demographics	VP ≥ 40% (n=50)	VP < 40% (n=132)	P value
Male	42 (84%)	99 (75%)	0.135
Age at implantation	61.6 ± 11.2	53.7 ± 14.7	<0.001
Secondary prevention	35 (70.0%)	91 (68.9%)	0.521
Basic HR(bpm)	61.8 ± 11.3	69.3 ± 13.0	<0.001
Basic PR(ms)	164.9 ± 29.1	185.7 ± 41.9	0.002
D‐­ICD	9 (18%)	31 (23.5%)	0.279
Echocardiography
LVEF (%)	40.6 ± 12.9	48.3 ± 14.3	<0.001
Comorbidities
LBBB	6 (12.0%)	9 (6.8%)	0.364
RBBB	4 (8.0%)	3 (2.3%)	0.091
Paroxysmal AF	6 (12.0%)	11 (8.3%)	0.013
CHD	20 (40%)	43 (32.6%)	0.385
ICD parameter
Basic rate (bpm)	51.3 ± 6.3	49.7 ± 5.3	0.08
Medications
Beta‐­blockers	43 (86.0%)	113 (85.6%)	0.577
Amiodarone	32 (64.0%)	63 (47.7%)	0.036
Endpoint event	23 (46.0%)	22 (16.7%)	<0.001

Abbreviations: HR, heart rate; D‐­ICD, dual chamber ICD; LVEF, left ventricular ejection fraction; LBBB, left bundle branch block; RBBB, right bundle branch block; AF, atrial fibrillation; CHD, coronary heart disease.

Table 2 Multivariate predictors of high Vp%

	Vp ≥ 40%	Vp < 40%	OR (95%CI)	p value
	(n = 50)	(n = 132)
Age at implant	61.6 ± 11.2	53.7 ± 14.7	1.039 (1.008‐­1.072)	0.014
LVEF	40.6 ± 12.9	48.3 ± 14.3	0.953 (0.926‐­0.980)	0.001
Basic HR	61.8 ± 11.3	69.3 ± 13.0	0.948 (0.916‐­0.980)	0.002

Abbreviations: LVEF, left ventricular ejection fraction; HR, heart rate.

AP19‐­01052

Spectrum of SCN5A rare variants in a cohort of young Singaporean men with suspected Brugada syndrome

Eric Lim; Boon, Yew Tan; Luo, Kai Wang; Sihui, Gina Lee, Daniel Chong, Mahesh Uttamchandani, Wee Siong Teo, Yu Yin Rita Yong

National Heart Centre, Singapore

Introduction:

Brugada syndrome (BrS) is an important heritable arrhythmic syndrome in which the commonest causative gene identified is SCN5A. However, the inheritance pattern of SCN5A is complex and distinguishing benign from pathogenic SCN5A variant alleles is not straightforward. To aid understanding of this problem, we report SCN5A rare variant prevalence in subjects with suspected BrS undergoing intravenous flecainide drug challenge (FC).

Methods:

This study was carried out at the national cardiovascular disease center of Singapore. Singapore is a multi‐­ethnic society which has a conscript military. Military pre‐­enlistees underwent screening with a targeted history, physical examination and 12‐­lead electrocardiogram. Subjects with a type 2 or 3 BrS ECG pattern were referred to electrophysiologists who evaluated and offered intravenous flecainide drug (FC) challenge as necessary (2 mg/kg over 10 minutes) together with SCN5A sequencing via targeted panel next generation sequencing coupled with confirmatory Sanger sequencing. Rare variants were then identified by comparison of the minor allele frequency (MAF) derived from a reference database (the gnomAD EAS dataset which includes ˜9K East Asians).

Result:

125 men with a mean age of 18 years agreed to both FC and SCN5A sequencing. 61 were FC positive, while 64 were FC negative. All 125 underwent SCN5A sequencing, and a total of 12 rare variants were identified at a MAF cut‐­off of 0.0006 ‐­ R225Q, A226V, G292S, R376C, R568C, A665T, S705F, R1027Q, Q1153H, E1225K, T1645M, S1776N. A226V, which has MAF (EAS) of 0.0013, was added to this list, as we have previously reported functional and pedigree studies confirming its pathogenicity. With this data, we performed an association study comparing rare variant alleles in the suspected BrS cohort versus those of gnomAD EAS (Table). This showed marked enrichment of SCN5A rare variants (OR = 2.3, P = .02). Further enrichment is shown in the FC positive subgroup (OR = 3.9, P = .0004), but no enrichment is evident in the FC negative subgroup (P = NS). The positive and negative predictive values, and sensitivity and specificity of a SCN5A rare variant to predict a positive FC was estimated as 83%, 55%, 16% and 97% respectively.

Conclusion:

We show that SCN5A rare variants are insensitive (16%) but specific (97%) for the prediction of drug‐­inducible BrS. This observation is consistent with an oligogenic model of BrS causation, where rare variants alone might be insufficient to lead to expression of the BrS phenotype but in conjunction with flecainide, leads to expression of the characteristic BrS ECG type 1 pattern. We believe this observation has implications for variant interpretation in BrS, which currently remains challenging. Larger cohorts will be necessary to confirm these observations. An important limitation of this study is that all subjects were male.

AP19‐­01092

Overdrive pacing to prevent ventricular tachycardia in patient with cardiac amyloidosis: A case report

Muhammadnur Rachim Enoch, Giky Karwiky, Mohammad Iqbal, Melawati Hasan, Januar W. Martha, Mohammad R. Akbar

Department of Cardiology and Vascular Medicine, Faculty of Medicine, Universitas Padjadjaran, Dr. H, Indonesia

Introduction:

Sudden death has been shown to be one of the most common cause of death in cardiac amyloidosis. However, implantation of implantable cardiac defibrillator (ICD) for prevention of sudden death in cardiac amyloidosis is uncertain. We reported implantation of permanent pacemaker with overdrive ventricular pacing in bradyarrhythmia cardiac amyloidosis with history of ventricular tachycardia (VT).

Methods:

A 57 years old man was scheduled for implantation of permanent pacemaker. He had history of syncope and was diagnosed with suggestive of cardiac amyloidosis with non‐­sustained VT 2 weeks ago. He had hemodialysis since 1 year ago. The ECG showed heart rate 52x/m, Qtc 490 milliseconds and frequent premature atrial contraction. Echocardiography showed dilated left atrium, concentric hypertrophy with septal thickness 15 mm, preserved LVEF without left ventricular outflow tract obstruction and features of relative apical sparing on deformation‐­based parameter. A permanent pacemaker were placed in mid septum right ventricle with single chamber mode, lower rate 60 bpm, upper rate 130 bpm. The night after implantation, the monitor captured episode of non‐­sustained VT. Therefore, we decided to overdrive pacing into 80 bpm, then 90 bpm. He also got antiarrhythmic drugs, such as amiodarone and bisoprolol. The patient died 24 hours after discharge from the hospital.

Result:

Sudden death are being the main causes of death in cardiac amyloidosis. Recorded VT is the marker late stage of cardiac amyloidosis and the mortality was high. Sudden deaths were mostly associated with terminal bradycardia followed shortly by pulseless electrical activity. Implantation of ICD for prevention of sudden death is uncertain and many deaths in patients with cardiac amyloidosis do not appear to be preventable by an ICD. Overdrive cardiac pacing was used for many years to prevent ventricular tachycardia and needed due to a high prevalence of conduction disease to prevent syncope. However pacemaker may not prevent sudden death because this is thought be often due to electromechanical dissociation

Conclusion:

Overdrive cardiac pacing can be alternative choice for prevention of ventricular arrhythmia and also have beneficial effects to prevent syncope in cardiac amyloidosis but still did not reduce mortality. Further studies would be useful to explore these findings in more detail.

AP19‐­01102

Genotypic association with tachyarrhythmia occurrence and sudden cardiac death risk in hypertrophic cardiomyopathy

Seong Soo Lee, Youngjun Park, Hee‐Jin Kwon, June Soo Kim, Kyoung‐Min Park, Seung‐Jung Park, Young Keun On

Samsung Medical Center, South Korea

Introduction:

Hypertrophic cardiomyopathy (HCMP) is the most commonly inherited form of heart disease, however, genotype‐­phenotype correlation has thus far been poorly described, especially in terms of atrial and ventricular tachyarrhythmia (ATa and VTa, respectively) and sudden cardiac death (SCD). Therefore, we sought to evaluate its genotypic association with ATa/VTa occurrence and SCD risk according to predefined risk factors.

Methods:

We evaluated a total of 23 different types of sarcomeric and non‐­sarcomeric genetic variations in 89 patients who were first diagnosed with HCMP. At the time of diagnosis, patients had undergone baseline echocardiography, heart magnetic resonance imaging (MRI), Holter monitoring, and treadmill test. Structured on the guidelines provided by The AMP and The ACMG, genetic variations were categorized as: pathogenic variant (PV), likely pathogenic variant (LPV), variant of uncertain significance (VUS), likely benign variant (LBV), and benign (BV). These groups were then subdivided into two groups: PV, LPV, and VUS were categorized as the gene detection group (D group), while LBV and BV was categorized as the gene non‐­detection group (ND group). Additionally, we evaluated SCD risk on the basis of the 2011 ACCF/AHA guideline.

Result:

From December 1995 to March 2016, a total of 89 patients were diagnosed with HCMP in our hospital. Within this study group, genetic variations were found in 55 patients (sarcomeric n = 51, 57.3%, non‐­sarcomeric n = 4, 4.5%), with patients identified as MYBPC3 (n = 24, 27.0%), MYH7 (n = 11, 12.4%), TNNI3 (n = 7, 7.9%), in the respective order of variation frequency. During patient follow‐­ups, AF incidence was reported in 4 patients (16.7%) from the MYBPC3 (+) group and 13 patients (20.0%) from the MYBPC3 (−) group, while VT was reported in 7 (29.2%) and 13 (20.0%) patients, respectively. Statistical analysis results indicated that differences among the two groups were not significant (P = 0.959 for AF, P = 0.527 for VT), and the presence of genetic variations of the MYH7 and TNNI3 genes was not significantly correlated with the occurrence of AF and VT (MYH7 P = 1.000 for AF, P = 0.983 for VT, TNNI3 P = 0.244 for AF, P = 1.000 for VT). In comparing D group and ND group, statistical analysis also showed no significant difference in incidence rates of AF and VT (AF 23.6% vs 11.8%, P = 0.268, VT 29.1% vs 11.8%, P = 0.101 in D and ND group, respectively). Although data analysis revealed non‐­ significant statistical results, SCD risk was considerably higher in the D group as compared to the ND group (49.1% vs 26.5%, p = 0.059).

Conclusion:

The correlation between the genetic variation of HCMP and incidence of ATa or VTa is unclear. Nonetheless, in consideration of the multiple risk factors associated with SCD occurrence, patients identified with genetic variations may have a higher chance of requiring subsequent ICD implantation.

AP19‐­01111

The risk of ventricular arrhythmia in HCM patients with atrial fibrillation

Yaxun Sun

Zhejiang University, China

Introduction:

Hypertrophic cardiomyopathy (HCM) is predisposed to arrhythmias including atrial fibrillation and ventricular tachycardia. Whether HCM patients with atrial fibrillation showed a higher risk of ventricular arrhythmias is still not clear.

Methods:

Patients with HCM hospitalized in Sir Run Run Shaw Hospital from January 2015 to December 2017 were consecutively recruited in this study. Every patient underwent body surface electrocardiograph, 12‐­lead electrocardiogram, collecting blood samples and clinical profiles. The patients were divided into several groups (AF group and non‐­AF group; VT group and non‐­VT group). Risk factors for AF or VT in patients with HCM were assessed by multivariate logistic regression analysis.

Result:

A total of 136 patients were recruited in this study. Genetic screening using whole exon sequencing in 45 patients. Among the 136 patients, 25.7%( 35/136) patients were with AF. Age [(66.3 ± 8.8) years vs (58.5 ± 12.1)years], New York Heart Association class (2.7 ± 0.63 vs 2.2 ± 0.04), left atrial dimension[(47.5 ± 11.0)mm vs (42.0 ± 8.8)mm],total cholesterol [(4.1 ± 0.7)mmol/L vs(4.7 ± 1.1)mmol/L] in the AF group were significantly higher than those in the non‐­AF group (all P < 0.05). Multivariate logistic regression indicates that advanced age (OR = 1.16, 95%CI 1.02˜1.31, P = 0.023), higher NYHA class (OR = 46.63,95% CI 5.4‐­401.1, P < 0.0001) and lower level of total cholesterol (OR = 0.23,95% CI 0.06‐­0.79,P = 0.02) were independent risk factors for AF in patients with HCM. Among them, 11.8% (16/136) were with VT. Risk of sudden death score[(4.9 ± 2.6)% vs (2.4 ± 1.7)%], ratio of man, syncope, complicated with DM, ICD implanted, smoking and non‐­left ventricular outflow tract obstruction in the VT group were much higher than those in the non‐­VT group (all P < 0.05). Multivariate logistic regression indicates that higher score of sudden death risk (OR = 2.19,95% CI 1.39‐­3.44,P = 0.001), complicated with DM (OR = 8.64,95% CI 1.3‐­58.8,P = 0.027) and non‐­left ventricular outflow tract obstruction (OR = 0.017,95% CI 0.001‐­0.418,P = 0.013) were independent risk factors for VT in patients with HCM.

Conclusion:

Advanced age, higher NYHA class and lower level of total cholesterol are independent risk factors for AF in patients with HCM. For this study, complicated with DM and non‐­left ventricular outflow tract obstruction are independent risk factors for VT in patients with HCM, but it needs further validation.

AP19‐­01149

High frequency of double mutations in RYR2 and genes related to long QT syndrome in patients with severe cardiac symptoms

Koichiro Takayama, Minoru Horie, Seiko Ohno

National Cerebral and Cardiovascular Center, Japan

Introduction:

Long QT syndrome (LQTS) is a disease characterized by QT prolongation and ventricular tachycardia. The main cause of LQTS is mutations in KCNQ1, KCNH2, and SCN5A. Some patients diagnosed with LQTS show severe phenotype compare to those with the same mutation. One of the reasons is an additional mutation related to arrhythmias, especially in RYR2 which is the major causative gene for catecholaminergic polymorphic ventricular tachycardia (CPVT). We aimed to clarify the characteristics of double mutation carriers.

Methods:

The study cohort consisted of 160 probands diagnosed with inherited primary arrhythmia syndrome and carrying RYR2 mutations. We performed genetic analysis for LQTS‐­related genes in addition to RYR2.

Result:

We identified 5 probands (2 male) with double mutations in RYR2 and LQTS‐­related genes; 3 KCNH2, 1 KCNQ1, and 1 SCN5A (Table). They all had symptoms and 3 probands suffered cardiopulmonary arrest. Their mean age at the onset was 9.8 ± 4.9 years old. Four probands (Proband 1, 2, 4, 5) experienced symptoms during exercise, and 3 of them were clinically diagnosed with CPVT. Remaining 1 proband (Proband 3) suffered CPA in the early morning and was clinically diagnosed with LQTS. The QTc interval of probands clinically diagnosed with LQTS (n = 2) was longer than that with CPVT (450.5 ± 30.5 vs 395.7 ± 0.6 milliseconds).

Conclusion:

Our study implied that LQTS patients carrying double mutations frequently suffered severe symptom. Therefore, cardiologists should be in mind that the patient may carry not only a mutation in a LQTS‐­related gene but also another mutation in other genes, even if the QT interval is prolonged.

Table Clinical and genetic characteristics of the probands with double mutations

Proband	Age at diagnosis	Age at onset	Sex	Clinical diagnosis	Symptom	RYR2		Double mutation
					Syncope	CPA	QTc (ms)	Nucleotide	Amino acid	Gene	Nucleotide	Amino acid
1	16	13	M	CPVT	(+)	(+)	396	1258C>T	R420W	KCNH2	3095G>A	R1032Q
2	15	4	M	CPVT	(+)	(+)	396	14593C>G	L4865V	KCNH2	43C>T	R15W
3	15	14	F	LQTS	(+)	(+)	481	1217C>T	S406L	KCNH2	3096_3109del	P1034GfsX80
4	11	5	F	CPVT	(+)	(−)	395	3766C>A	P1256T	SCN5A	2441G>A	R814Q
5	32	13	F	LQTS	(+)	(−)	420	477G>T	W159C	KCNQ1	828_830del	S277del

Abbreviation: CPA, Cardiopulmonary arrest.

AP19‐­01152

Management of high‐­risk congenital long QT syndrome with atrioventricular block in fetal and neonatal life

Lisheng Lin, Hitoshi Horigome, Junko Shiono, Mari Iwamoto, Naoki Ohashi, Hiroko Goto, Tsugutoshi Suzuki, Kazuhiro Takahashi, Masaru Miura, Masao Yoshinaga, Naokata Sumitomo

Ibaraki Children's Hospital, Mito, Japan, Japan

Introduction:

Fetal sinus bradycardia combined with 2:1 atrioventricular block (AVB) or intermittent ventricular tachycardia (VT) is important clues to the diagnosis of congenital long QT syndrome (LQTS). LQTS patients with 2:1 AVB usually manifest in fetal or neonatal period, and tend to show severe clinical course, leading to a poor prognosis. However, long‐­term outcome of these particular patients remain unclear. The purpose of this study is to evaluate the clinical course, genotype, medication, device therapy, and prognosis of fetal and neonatal LQTS with 2:1 AVB.

Methods:

Fetuses and neonates diagnosed with congenital LQTS were registered from 44 institutions/ hospitals in Japan using questionnaire. Clinical course, genotypes, treatment, and prognosis were compared between (a) patients with 2:1 AVB (AVB group; n = 35) and (b) patients without AVB (non‐­ AVB group; n = 53).

Result:

Eighty‐­eight patients were registered. (a) Age at diagnosis: 43% and 57% of the cases were diagnosed during fetal and neonatal period in AVB group, respectively, compared to 19% and 81% in non‐­AVB group. (b) Family history of LQTS or sudden cardiac death (SCD) was positive in 20% in AVB group and 51% in non‐­AVB group. (c) The proportion of LQTS genotypes: LQT1 0%, LQT2 17%, LQT3 23%, LQT8 14%, unknown/untested 46% in AVB group, whereas LQT1 30%, LQT2 15%, LQT3 13%, unknown/untested 42% in non AVB group. (d) ECG findings: the mean QTc values were 579 milliseconds and 523 milliseconds; VT/ torsade de pointes (TdP) occurred in 32% and 17% in AVB and non‐­AVB groups, respectively. (e) Medication: 86% and 57% of the patients received medication in AVB and non AVB groups. Mexiletine was used most frequently (74%) in AVB group, while propranolol was chosen as the first line drug (57%) in non‐­AVB group. (f) Device therapy: 40% and 6% of the patients received device therapy in AVB and non AVB group. (g) Prognosis: mortality rate was 23% and 4% in AVB and non‐­ AVB group (median follow‐­up period of 4 years and 3 months). Kaplan‐­Meier analysis revealed lower survival probability in AVB group (Figure). There was only one death noted among patients who received device therapy in neonatal period.

Conclusion:

Fetal and neonatal LQTS with 2:1 AVB tend to develop VT/TdP, leading to poor prognosis. Frequently identified genotypes in these patients were LQT2 and LQT3, and none of the patients with LQT1 (KCNQ1 mutation) showed this phenotype. Device therapies were required in many patients, and were considered effective. However, the percentage of patients who received device therapy was still low in Japan compared to that reported from other countries. Aggressive device therapy in addition to medication should be considered in fetal and neonatal LQTS with AVB.

AP19‐­01165

Diagnostic usefulness of implantable loop recorder in patients with unexplained syncope

YUN YOUNG CHOI, Jong‐Il Choi, Jaemin Shim, Yun Gi Kim, Kwang‐No Lee, Ki Yung Boo, Do Young Kim, Ha Young Choi, Young‐Hoon Kim Kim

Korea University Anam Hospital, South Korea

Introduction:

In substantial proportion of syncope, exact cause is not identified because it is difficult to document ECG correlated with event. Thus, an implantable loop recorder (ILR) was introduced for diagnosing with hidden arrhythmia, however, its clinical use is still limited number. We aimed to assess the diagnostic value of ILR for unexplained syncope.

Methods:

Between May 2016 and June 2019, all consecutive patients who underwent ILR implantation were studied. We analyzed the electrocardiogram stored in the device.

Result:

Among 57 patients (32 male, mean age 52 ± 20 years old) with unknown causes of syncope, during two years follow‐­up, arrhythmia was detected in sixteen patients (28%). Thirteen (22.8%) patients received permanent pacemaker implantation due to symptomatic bradycardia, and all of the arrhythmia was detected between 1 months and 21 months. Eight patients (14%) showed sick sinus syndrome (5 long pause ; 3 tachycardia‐­bradycardia syndrome). Five patients (8%) had paroxysmal atrioventricular block. One of the patients with permanent pacemaker implantation was positive in the tilt table test. Two patients underwent radiofrequency catheter ablation for paroxysmal supraventricular tachycardia and atrial fibrillation. The mean duration of the first event was 170 days.

Conclusion:

This study showed that ILR monitoring detected substantial number of significant bradycardia in patients with unexplained syncope, suggesting that it is an effective diagnostic method that allows to shorten the time for identifying arrhythmic causes.

AP19‐­01169

General population's eagerness in learning basic life support: A study from online questionnaire

Wendy Wiharja

Universitas Pelita Harapan, Indonesia

Introduction:

Basic life support (BLS) performed by general population improves outcomes in cardiorespiratory collapse, yet less than 1% of the general population can perform it effectively. Improper BLS responses were common in out‐­of‐­hospital cardiac arrest treated with public automated external defibrillator. A study showed that course repetitions affected success in performing BLS. Those with repeated participation in BLS obtained significantly better results than course participants with no relevant previous knowledge. Periodic training for proper BLS is necessary for both healthcare and non‐­ healthcare personnel. BLS course and information is important to achieve fluency. This clinical study aims to measure general population's eagerness in learning BLS as a basis for BLS campaign.

Methods:

Online Questionnaire was created using Google Sheet Form, link: https://goo.gl/eQZ0N. This link was broadcasted using LINE, WhatsApp, and BBM application as media. Simple randomized sampling was used. There was “only for a non‐­medic society” note inside the questionnaire, for limiting sample bias. Majority of respondents’ last educational level were high school (58%) and undergraduate (38%), others (4%). Our questionnaire gave impression about respondents’ eagerness in learning more about BLS, it consists of 4 questions: 1. The importance of knowing BLS according to their point of view, 2. Their eagerness to learn about BLS, 3. History of previous BLS training, 4. Have they ever read about BLS.

Result:

294 (97%) of respondents’ state that knowledge about BLS is important, 222 (73.5%) of responders are eager to learn how to do BLS. Only 120 (39.6%) of respondents have ever done BLS training, and there are 180 (59.4%) of respondents that have ever looked for information or read about BLS.

Conclusion:

These results looked promising, a majority of respondents (97%) wanted to know BLS better and more than half of them (73.5%) wanted to learn about it. Even though only one‐­third of respondents have ever done BLS training, and only one‐­half of respondents ever looked for information about BLS. The results were admirable and encouraged us that BLS training, information and awareness campaign through mass media (TV, Pamphlet, magazine, etc.), which may reduce cardiac arrest mortality on large scale. BLS should also be included in school curriculum.

AP19‐­01175

Sudden cardiac death in tuberculous myocarditis, a review

Benedictus Hanjaya Suwandi

Faculty of Medicine, Airlangga University, Indonesia

Introduction:

Tuberculosis (TB) is still a big burden for Indonesia and the rest of the world. The increase of TB prevalence urges the consideration of potentially fatal tuberculous myocarditis. Myocarditis is one of rare cardiac involvement in TB infection. With its vast variability of clinical manifestations from asymptomatic to sudden cardiac death (SCD), TB myocarditis is very difficult to study. Histopathological examination is needed to confirm the diagnosis, which is usually being made at autopsy.

Methods:

Three recognised histopathological types of myocardial involvement in TB are nodular tubercles with central caseation (tuberculoma), miliary tubercles as a complication of systemic miliary dissemination which spread hematogenously, and diffuse infiltration by granulomas containing Langhans giant cells, epitheloids and lymphocytes. The exact pathomechanism of TB myocarditis remains unclear. Infiltration to myocardium may occur by hematogenous seeding, direct invasion from pericardium, or retrograde lymphatic spread via mediastinal lymph nodes. Clinical manifestations of TB myocarditis varies from clinically asymptomatic with post‐­mortem examination as the base of diagnosis; conduction failure such as long QT syndrome or atrioventricular block due to extensive disease surrounding conducting tissue; intractable arrhythmias including atrial fibrillation, paroxysmal ventricular tachycardia, ventricular fibrillation; valve dysfunction, obstruction of the superior vena cava, right ventricular outflow tract, or pulmonary veins due to obstructive lesions caused by large nodular tubercles; congestive heart failure; even SCD. Definitive diagnosis can only be made by endomyocardial biopsy with proof of TB infection in myocardium such as by PCR, culture, or staining of acid‐­fast bacilli of myocardial tissue sample supported by suggestive radiological imaging such as serial late gadolinium enhanced MRI.

Result:

Due to the limitation of ante‐­mortem case findings, the mechanism of SCD is very difficult to be determined. Hypothesised mechanisms include ventricular arrhythmia due to granulomatous proliferation in the interventricular septum structures, impaired myocardial contractility, cardiac rupture, coronary occlusion, obstruction to pulmonary blood flow leading to fatal haemorrhage, and cardiopulmonary collapse leading to bradycardia. Risk stratification and interventions with implantable cardiac defibrillator are extremely difficult as risk factors such as family history are absent and patients are usually asymptomatic in TB myocarditis. Anti‐­tuberculosis chemotherapy is effective in improving clinical conditions and shorten hospital stay for patient with TB myocarditis, but it has no benefit in the prevention of SCD.

Conclusion:

Therefore, greater awareness concerning TB myocarditis with early and prompt diagnosis should be raised to improve the outcomes and prevent SCD for this rare cardiac involvement in TB infection.

AP19‐­01183

Early response to cardiac arrest: A general population study using online questionnaire

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

Universitas Pelita Harapan, Indonesia

Introduction:

Basic life support performed by general population improves outcomes in cardiorespiratory collapse, yet less than 1% of the general population can perform it effectively. Strengthening the community response to cardiac arrest by training and empowering more bystanders to perform CPR and by increasing the use of Automated External Defibrillators (AEDs) at least doubles the chances of survival and could save thousands of lives each year. Once cardiac arrest has occurred, early recognition is critical to enable prompt initiation of bystander CPR. The immediate initiation of bystander CPR can double or quadruple survival from out‐­of‐­hospital cardiac arrest. Despite this compelling evidence, only 40% of victims receive bystander CPR. This study aims to gain information about general population's early recognition knowledge.

Methods:

Online Questionnaire was created using Google Sheet Form, link: https://goo.gl/eQZ0N. This link was broadcasted using LINE, WhatsApp, and BBM application as media. Simple randomized sampling was used. There was a “only for a non‐­medic society” note inside the questionnaire, for limiting sample bias. There were 303 responders (160 male, and 143 female), age > 17 years old. Majority of responder's last educational level were high school (58%) and undergraduate (38%), others (4%). The questions inside the questionnaire tend to detect the early response of responders as bystander using 4 criterions: (a) Responder's reaction, (b) Location for checking pulse, (c) Chest compression method, (d) Ventilation method.

Result:

From the questionnaire, we found that 192 (63.6%) of responders tend to call ambulance for the first reaction, then 284 (93.7%) of responders will try to check pulse on the neck. 233 (77.4%) of responders know that chest compression was done on mid‐­chest, 246 (81.5%) of responders know that CPR should be done repeatedly with specific rhythm. Only 150 (49.5%) of responders want to give mouth‐­to‐­mouth ventilation.

Conclusion:

From the result, we conclude that our responders have a good knowledge about how they react as a bystander while encountering unconscious person and overall result was satisfying. A continuing seminary using mass media and workshop about Basic Life Support is encouraged. We plan to expand our study to reach community nationwide.

AP19‐­01191

Diagnostic and therapeutic management for recurrent syncope presented in patient with suspected Brugada type 3 and sinus pause (case report)

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

Universitas Pelita Harapan, Indonesia

Introduction:

Brugada syndrome and SA node dysfunction are rhythm dysfunctions which resulting in recurrent syncope as the main symptom, through reducing excitability and impairing conduction of impulses generated in the sinus node. This case report intends to describe the diagnostic and therapeutic management for the patient presented with such condition.

Methods:

A 35 years old male presented with recurrent syncope, three times a week, since 2 weeks ago. He had a familial history of Sudden Cardiac Death (SCD), his uncle died at age 50 years old because of SCD. On physical examination: BP (110/70 mmHg), Pulse (60 BPM), RR (20x/minute), others physical examinations were unremarkable. Electrocardiography examination showed: bradycardia with sinus pause < 3 seconds, and suspected Type 3 Brugada. Chest X‐­ray showed no abnormalities. After the patient stabilized in ER, he was referred for further examination.

Result:

Both Brugada syndrome and SA dysfunction may occur concomitantly through mutation in SCN5A gene. Mutations in SCN5A does not only affect cardiac Inward Natrium channel but also Calcium channel, coupled with the negative shift in the voltage‐­dependence of inactivation caused a prolongation of Action Potential Depolarization (APD) and a slowing of phase 4, which together are responsible for the Brugada syndrome, bradycardia, and sinus node dysfunction. Diagnostic and therapeutic management for our patient should be start with Ajmaline Test, for unmasking Brugada type 1. Positive Ajmaline test result with history of syncope means the need of Implantable Cardioverter Defibrillator (ICD) implantation. While negative Ajmaline test result leans on SA dysfunction as the cause of syncope, and might be a candidate for Percutaneous Pacemaker (PPM) therapy. Since the sinus pause that happened in the patient is <3 seconds, even though the patient is symptomatic, the PPM therapy can be delayed and the patient might be put on Holter monitoring for further study to show episode of >3 seconds sinus pause or aborted VT, if any.

Conclusion:

Diagnostic and therapeutic strategy for the recurrent syncope in patient with suspected Brugada type 3 and SA node dysfunction may depend on Ajmaline test. ICD implantation is obligated therapy if Ajamaline test resulted positive. PPM and Holter monitoring therapy is chosen depend on the sinus pause duration.

Keywords: Brugada, SA dysfunction, Ajmaline, ICD, PPM, Holter

AP19‐­01207

Wide QRS complex and the risk of ventricular arrhythmia or sudden cardia death in Brugada syndrome patients: A systematic review and meta‐­analysis

Pattara Rattanawong, Wasawat Vutthikraivit, Prapaipan Putthapiban, Jakrin Kewcharoen, Chanavuth Kanitsoraphan, Narut Prasitlumkum, Poemlarp Mekraksakit, Raktham Mekritthikrai

Mayo Clinic, United States

Introduction:

Brugada syndrome (BrS) is an inherited arrhythmic disease associated with fatal ventricular arrhythmia (VA) and sudden cardiac death (SCD). Primary prevention of SCD in BrS has been recognized as important; however, ventricular arrhythmia risk stratification remains challenging and controversial. Previous studies reported that QRS duration may be useful as a predictor of VA or SCD in BrS patients. We aimed to assess the correlation of wide QRS complex with the incidence of VA or SCD event by a systematic review and meta‐­analysis.

Methods:

We comprehensively searched the databases of MEDLINE and EMBASE from inception to June 2019. Included studies were cohort (prospective or retrospective) and case control studies that reported the relationship between wide QRS complex (>120 msec) and VA or SCD. Data from each study were combined using the random‐­effects, generic inverse variance method of DerSimonian and Laird to calculate pooled odds ratio (OR) and 95% confidence intervals.

Result:

Four studies from 2005 to 2014 were included in this meta‐­analysis involving 878 BrS patients (134 with VA or SCD and 744 without VA or SCD). The mean age was 45.2 ± 14.7 years. The patients were predominately men (84%). Wide QRS complex was an independent predictor of VA/SCD events. (pooled OR 2.26, 95 % confidence interval: 1.41‐­3.62, P < 0.001, I2 = 2.9%).

Conclusion:

Our study demonstrated that wide QRS complex is associated with 2.26 times higher risk of VA or SCD in BrS populations. Wide QRS complex is a useful risk stratification in prediction of VA or SCD events in patients with Brugada syndrome, especially when determining implantable cardioverter‐­ defibrillator placement in asymptomatic patients.

AP19‐­01210

T‐­peak to T‐­end interval and the risk of ventricular arrhythmia or sudden cardia death in Brugada syndrome patients: a systematic review and meta‐­analysis

Pattara Rattanawong, Wasawat Vutthikraivit, Prapaipan Putthapiban, Narut Prasitlumkum, Raktham Mekritthikrai, Jakrin Kewcharoen, Chanavuth Kanitsoraphan, Poemlarp Mekraksakit, Tachapong Ngarmukos

Mayo Clinic, United States

Introduction:

Brugada syndrome (BrS) is considered as an inherited arrhythmic disease associated with fatal ventricular arrhythmia (VA) leading to sudden cardiac death (SCD). Hence, risk stratification in BrS for prediction of VA in asymptomatic patient is very important. Previous studies reported that prolongation of T‐­peak to T‐­end interval (Tpe interval) in electrocardiogram may be associated with VA or SCD events. We aimed to assess the correlation of Tpe interval with the incidence of VA or SCD event by a systematic review and meta‐­analysis.

Methods:

We comprehensively searched the databases of MEDLINE and EMBASE from inception to June 2019. Included studies were cohort (prospective or retrospective) and case control studies that reported the relationship between Tpe interval and VA or SCD. Studies using cut‐­off value of Tpe interval were excluded since each study had different value. Data from each study were combined using the random‐­effects, generic inverse variance method of DerSimonian and Laird to calculate pooled odds ratio (OR) and 95% confidence intervals.

Result:

Four studies from 2010 to 2018 were included in this meta‐­analysis involving 506 BrS patients (97 with VA or SCD and 409 without VA or SCD). The mean age was 44.5 ± 13.6 years. The patients were predominately men (86%). The prolongation of T‐­peak to T‐­end interval increased odds of VA/SCD events by 5% in each one msec prolongation of T‐­peak to T‐­end (pooled OR 1.05, 95 % confidence interval: 1.02‐­1.08, p < 0.001, I2 = 59.8%).

Conclusion:

Our study demonstrated that the prolongation of T‐­peak to T‐­end interval increased odds of VA/SCD events by 5% in each one msec prolongation. T‐­peak to T‐­end interval is a useful risk stratification tool in Brugada syndrome.

AP19‐­01257

Recurrent stress cardiomyopathy with ventricular fibrilliation

Muthiah Subramanian, Hisham Ahamed, Navin Mathew

CARE Hospital, Hyderabad, India

Introduction:

Life‐­threatening ventricular arrhythmias (VA) have been reported in 3‐­10% of patients with stress cardiomyopathy (SC). The role of implantable cardioverter‐­defibrillators (ICD) in SC patients with recurrent Vas is uncertain. We describe a case of recurrent ventricular fibrillation (VF) in a patient with multiple episodes of recurrent SC who subsequently underwent an ICD for secondary prevention.

Methods:

N/A.

Result:

A 55‐­year old woman with a history of diabetes mellitus presented with sudden onset chest pain hours following the death of her husband. Her baseline ECG showed 1 mm ST depression and T wave inversions in the anterolateral leads with a QTc interval of 510 milliseconds. Her troponin I level was 11.2 ng/ml. Echocardiography revealed an ejection fraction of 35% with apical akinesis and hyper‐­contractile basal segments. Coronary angiography revealed mild coronary artery disease in her right coronary artery. Eight hours following admission she had an aborted cardiac arrest with VF. Serial ECGs during the next 48 hours revealed lengthening of QTc interval to a maximum of 560 milliseconds. She did not have any subsequent VAs during her hospital admission. Ejection fraction normalised within 6 days and she was discharged with beta blockers and angiotensin‐­converting enzyme inhibitors. After 4 weeks, she presented again with aborted cardiac arrest (VF) and was successfully resuscitated in the emergency room. Echocardiography and coronary angiography confirmed a recurrence of SC. Baseline QTc interval was 530 milliseconds. Following a short hospital admission, her echocardiogram normalised. She was advised an ICD, but the patient deferred further management. She suffered from a third aborted cardiac arrest with VF after 5 months. Echocardiography confirmed a third episode of SC. Baseline QTc was 550 milliseconds. During this admission she elected to proceed with an implantation of an ICD. The patient was discharged with no further hospital events. She is currently doing well after 1 year with no subsequent device therapy and no further recurrence of SC.

Conclusion:

This report highlights the risk of recurrent VF in patients with SC. Patients with SC and recurrent VAs may be considered for ICD implantation for secondary prevention.

AP19‐­01266

AV node dysfunction in mobitz type I and its clinical manifestations

Elizabeth Marcella, Karlina Alferinda, Hans Nuari, Carol Natasha, Joey Martinus Sidarta, Vito Anggarino Damay

Pelita Harapan University, Indonesia

Introduction:

Heart obstruction has a better prognosis with early recognition and appropriate management. Unlike type II, even though Mobitz type I is often asymptomatic and rarely progresses into full AV obstruction, in the case of myocardial ischemia or myocarditis, it may result in clinical deterioration due to a reduction of cardiac output.

Methods:

A 42‐­yo female was admitted to the Heart Department due to frequent loss of consciousness since she was 12, which had considerably worsened in the last 3 weeks before admission. She would often lose consciousness after standing for too long under heat or after 15 minutes of stomachache, with the feeling of extreme heart rate, lethargy, darkening sight, and cold sweat as pre‐­determining symptoms. The patient would usually regain consciousness after 15 minutes, with the latest episode being 3 days ago. The patient had undergone Holter test 9 months prior with resulting in infrequent premature atrial complex and normal ECG. Upon inspection, vital signs were recorded with the blood pressure of 120/80 mmHg, pulse rate of 81×/minute, respiratory rate of 18x/minute, and body temperature of 36.6°C. ECG was performed and sinus tachycardia was found, with a PR interval of 0.16 seconds, left axis deviation, poor R wave progression, right ventricle hypertrophy, QT interval of 0.32 seconds, and inverted T wave in V5 and V6. An electrophysiology test was done, and the AV node dysfunction was found.

Result:

Syncope can be defined as a temporary loss of consciousness due to cerebral hypoperfusion. One of the causes being a decrease in cardiac output due to heart abnormalities. The obstruction of the heart happens when impulse from the atrium to the ventricle is interrupted due to anatomical or functional abnormalities. PR interval can be used to measure conduction from the atrium to the ventricle, including atrial depolarization (P wave) and subsequent conduction within AV nodes, His‐­bundles, and Purkinje fibers. Normal PR interval ranges from 120 to 200 milliseconds. The lengthening of the PR interval suggests a delay in conduction from the atrium to the ventricle, which most commonly happens in the AV node and is classified as the first degree of heart obstruction. The second degree of heart obstruction indicates intermittent conduction from the atrium to the ventricle (Mobitz type I/Wenckebach and Mobitz type II), where P wave fails to reach the ventricle.

FIGURE 2 The standard ECG 12‐lead findings of patient

Conclusion:

PR interval can indicate heart obstructions. The management of Mobitz type I varies in severity and symptoms and the knowledge should be mastered by staff to deliver the appropriate treatment strategies.

Keywords: AV node dysfunction, PR interval, ECG, Mobitz type I, syncope

AP19‐­01281

Malignant arrhythmia secondary to early repolarization in a 27 year‐­old male, the J wave syndrome: A case report

Timothy Bjorn Lagos, Michael Agbayani, Joseph Marc Seguban

Philippine Heart Center, Philippines

Introduction:

The J wave is a deflection noted after the QRS complex on ECG. Its manifestation as an early repolarization pattern has emerged as a pro arrhythmic state rather than a benign abnormality and is being hypothesized and recognized as a cause of idiopathic ventricular fibrillation leading to sudden cardiac death at 0.9% worldwide. Current evidence associating early repolarization with the development of malignant arrhythmia is limited.

Methods:

Highlighted is a 27 year‐­old male with no known comorbidity, an occasional smoker, alcoholic beverage drinker and no history of illicit drug use presenting with intermittent palpitations for a year presenting with a few hour history of severe epigastric pain and loss of consciousness. Ventricular fibrillation was later noted and defibrillation was done. The patient reverted to sinus rhythm and was confined. An acute coronary syndrome was entertained and medications were started. Electrolytes, acute phase reactants, and thyroid hormones were determined and were all normal. Troponin was elevated. A

12 lead ECG showed sinus rhythm with up slopping of the J wave of at least 2 mm in the inferolateral leads. 2D echocardiography, cardiac MRI, and coronary angiogram were all unremarkable. A diagnosis of J wave syndrome was made. Cilostazol 200 mg/tablet per day was started and a single chamber implantable cardioverter defibrillator was placed for secondary prevention. No recurrence of the arrhythmia was noted and the patient was discharged.

Result:

Early repolarization pattern is an incidental finding in normal individuals, especially in males, athletes and African Americans. It has been occasionally noted to emerge just before the onset of ventricular fibrillation. Early studies lead to the current criteria for evaluating the J wave as benign or malignant. These criteria include the J point elevation, height of the J wave, slope of ST segment (up sloping, horizontal or down sloping), and number of contiguous ECG leads involved. In this case report, accounting the history, the normal results of both non invasive and invasive tests, coupled with the characteristic ECG changes, type 2 early repolarization was established and managed accordingly. Subsequent device interrogation on follow‐­up showed no arrhythmia recurrence.

Conclusion:

The data on the prevalence of early repolarization as a prelude to the occurrence of ventricular arrhythmias in healthy patients is growing. Correlation with certain genes and specific phenotypes are still being discovered and its causation for sudden cardiac death is yet to be established. Due to this rarity, facts are insufficient to provide adequate evidence to create guidelines, support screening methods, and improve current treatment strategies.

AP19‐­01291

Primary cardiac electrical diseases: Characteristic and outcomes of the patients from Thailand

Satchana Pumprueg, Tomon Thongsri

Siriraj hospital, Mahidol University, Thailand

Introduction:

Primary cardiac electrical disease is a group of diseases causing sudden cardiac death in apparently normal structural heart. This is the leading cause of sudden death in healthy adult. We report the baseline characteristic and prospective outcomes from our database.

Methods:

Patients with primary cardiac electrical disease who had their follow up visit at Budhachinnarat hospital, and Siriraj Hospital, Thailand were enrolled to our study. Baseline characteristic as well as follow up data regarding to incidence of fatal cardiac arrhythmia and death were recorded in the database. Patients were contacted yearly to assess for vital status and clinical condition. For secondary ICD prevention patients, arrhythmia status was recorded from ICD interrogation.

Result:

There were 160 patients enrolled from 2 cardiac centers. Most were male (70%). Mean age was 42.5 ± 11.2 years old. Mean follow up period was 32.1 ± 10.5 months. There was not death in this patient cohort. Brugada syndrome was the most common disease in this cohort as 65.6% of the patients were diagnosed with this condition. Less frequent diseases included premature ventricular contraction/ ventricular tachycardia, and long QT syndrome for which 12.5% and 11.2% of the patients were diagnosed with respectively. Majority of patients experienced prior sudden death episode (61.2%).

71.8% of the patients underwent ICD implant. Among patients who had ICD implant for secondary prevention, recurrent fatal ventricular arrhythmia rate was 35.7%. None of the patient who had ICD implant for primary prophylaxis experienced fatal ventricular arrhythmia episode. There was not any parameter that could predict future fatal cardiac arrhythmia except history of sudden death.

Conclusion:

Brugada syndrome is the most prevalence primary cardiac electrical disease from out study. ICD therapy is very effective and should be considered as standard therapy for patient who experienced prior sudden cardiac death. We could not identify any parameter that could predict future fatal arrhythmia in patients who had not experienced the episode before.