Ventricular tachycardia ablation using brachial artery access and integrated cardiac imaging

Key Teaching Points.

• •Ventricular tachycardia (VT) ablation in patients with no femoral arterial or venous access can be performed through the brachial artery and vein.
• •Brachial artery and vein cutdown is an efficient, safe method for upper extremity access to the heart. Right brachial artery access can make navigating to the descending aorta more challenging as compared to the left side.
• •Integrated imaging can help reduce the time needed to perform an electroanatomic map, especially when performing VT ablation from a less frequently used access point.

Introduction

Ischemic scar–mediated ventricular tachycardia (VT) ablation has evolved to being performed through the femoral vein and femoral artery with either transseptal or retrograde access to the left ventricle (LV). However, in some patients with severe peripheral arterial disease, access to the LV via the femoral vein or artery may not be possible.

We present a case of a patient with recurrent ischemic scar–mediated VT and implantable cardioverter-defibrillator who had undergone 2 Fem-Fem surgeries and was not felt to be an appropriate candidate for vascular access through the femoral vein or artery by vascular surgery. After discussion with the patient and vascular surgery, we performed VT ablation through the right brachial artery and vein via a cutdown approach, and used integrated (inHEART) imaging to assist with procedural mapping and ablation. To our knowledge, this is the first reported case of VT ablation performed via the right brachial artery and vein using an irrigated catheter, with inHEART imaging.

Case report

The patient is a 72-year-old man with history of smoking, coronary artery disease status post myocardial infarction, coronary artery bypass graft surgery, ischemic cardiomyopathy, peripheral arterial disease, with recurrent VT despite being on sotalol. The patient had recently undergone a second left femoral artery to right femoral artery bypass with prosthetic graft, 6 months earlier. His ejection fraction by echocardiogram was 31%. He was switched to amiodarone briefly, but did not wish to be on amiodarone long term and wished to proceed with VT ablation. After reviewing with vascular surgery and with the patient, we elected to proceed with ablation through the brachial artery. Cardiac computed tomography (CT) was performed specifically with postprocessing using inHEART.

Right brachial artery and vein cutdown was performed by vascular surgery (Figure 1A) in the electrophysiology lab using the right arm, based on operator preference. Anesthesia was provided using moderate sedation. Initially, we thought access from the right arm would be more consistent with our usual workflow when performing ablation from the right side of the patient. A short 9F sheath was placed in the vein, and a long SR0 8.5F sheath was placed in the brachial artery (Figure 1B) under direct visualization. Through the brachial vein sheath, a decapolar (Decanav; Biosense Webster, Irvine, CA) catheter was advanced to the right ventricle. Three-dimensional mapping of the coronary sinus, His bundle, and superior vena cava were performed to allow for registration to the inHEART previously acquired map.

Figure 1.

A: Cutdown of right brachial artery and vein is shown. B: Insertion of long TourGuide sheath (Medtronic, Dublin, Ireland) into right brachial artery and short sheath into right brachial vein.

Significant difficulty was encountered approaching the LV with the SR0 sheath from the right brachial artery, as the approach from the right brachial artery favored the wire, sheath, and catheter to move across the aortic arch and down the descending aorta (Figure 2A). We were able to use a stiff Amplatz XTSF wire (Cook Medical, Bloomington, IN) advanced through a JR4 catheter to cross the aortic valve and enter into the LV. After this, a TourGuide sheath (Medtronic) was advanced over the JR4 and Amplatzer XTSF wire into the aortic root (Figure 2B). Once the TourGuide sheath was advanced into the aortic root, the ablation catheter (ThermoCool SmartTouch D/F curve; Biosense Webster) was advanced into the LV.

Figure 2.

A: Fluoroscopic picture of TourGuide sheath (Medtronic) advanced over Amplatzer XTSF wire from right brachial artery into right subclavian artery toward the arch of the aorta. The Amplatzer XTSF wire is shown in the aortic root. B: Fluoroscopic picture of TourGuide sheath through the aortic valve with ablation catheter in the left ventricle (LV). The decapolar catheter is also shown in the coronary sinus (CD), delivered through the right brachial vein.

The endocardium was mapped using the ablation catheter identifying the LV apex, LV base, and areas of abnormal LV voltage. The inHEART cardiac CT was then merged.

Programmed stimulation was performed from the right ventricle apical catheter, inducing the patient’s clinical VT cycle length 323 ms (Figure 3A) with right bundle branch block left superior axis morphology. It was not well tolerated and was pace terminated. Radiofrequency ablation (40 W, maximum temperature 43°C) was then performed targeting local abnormal ventricular activity (LAVA),¹ and using pace mapping to determine possible exit sites for the VT. Channel ablation using the inHEART map was also performed (Figure 3B). Postablation the patient’s clinical VT was not inducible, and only nonclinical ventricular flutter was induced and cardioverted to sinus.

Figure 3.

A: Electrocardiogram of ventricular tachycardia induced with right bundle branch block superior axis. B: Inferior view of the left ventricle endocardial voltage map (left) and inHEART computed tomography (right) showing wall thickness (maroon 1 mm, orange 2 mm, yellow 3 mm). Ablation lesions are shown on the left image.

At the end of the procedure, vascular surgery assisted with closure of the access site, with 6-0 prolene used to close the arteriotomy and venotomy. The patient recovered well and was discharged the following day. He has been seen at 1 month follow-up and has not had any complaints or issues with access through the arm, nor has he had any recurrent VT.

Discussion

This is the first case report, to our knowledge, of a patient who underwent VT ablation using an irrigated ablation catheter (ThermoCool SmartTouch; Biosense Webster) through the right brachial artery with integrated imaging (inHEART) mapping technology. Although this technique was sometimes used in the early days of intracardiac shock ablation for VT,² only 2 other case reports exist in the literature describing ventricular arrhythmia ablation through the upper extremity. One previous case report describes performing VT ablation though the right radial artery using a 6F ablation catheter with a 4 mm tip.³ The other case report, published in Europace,⁴ describes ablation of premature ventricular contractions from the right coronary cusp using a 7F ablation catheter inserted through the right brachial artery.

The use of integrated imaging (inHEART) during brachial artery access to facilitate the VT ablation procedure was also extremely valuable. Integrated imaging for VT ablation has more recently become available to help guide ablation by providing anatomical as well as substrate information. Previously published studies^5,6 have demonstrated in ischemic cardiomyopathy that the previously acquired cardiac CT images can be used to assess for wall thinning, which has been associated with scar and LAVA by electroanatomic mapping, and hence eliminate the need for high-density voltage mapping. It also allows for preprocedural planning (catheter and sheath choice) by defining the target substrate prior to starting the procedure. In this case, we were able to register the CT image using CartoSound (Biosense Webster), and also by acquiring geometry of the superior vena cava, inferior vena cava, coronary sinus, and aortic root. By using the registered image, we did not acquire a high point density, but rather focused on using the CT image to guide location of diseased substrate. Within those areas, LAVA and channels between areas of denser scar were targeted for ablation.

There were several other important lessons learned from this case. The first is that approach to the LV from the right arm can be more challenging, as the natural direction when moving the catheter forward is to move right to left across the aortic arch down the descending aorta. Although working from the right arm is more in line with how electrophysiologists are used to moving catheters, similar to the femoral approach, we and our vascular colleagues would recommend approaching the LV from the left brachial artery. The vascular surgeons often face a similar but opposite issue when accessing mesenteric arteries from the left brachial approach, and usually find that their catheters and wires cross the arch to the ascending aorta, and need deflectable sheaths to move posterior. We encountered the opposite challenge when entering the arterial system from the right brachial artery, as our wires and catheters required a deflectable sheath placed into the arch of the aorta and then ascending aorta to move catheters to the LV.

There may also be a mechanical advantage to being closer to the LV from the brachial level of entry into the arterial system. Current catheters are designed to carry torque and deflection down a longer distance; however, invariably some of the motion from the operator’s hand will not be translated effectively distally. Future studies are needed to determine if access from the brachial artery confers additional benefit in maneuvering the catheter.

The arm approach, and more specifically a cutdown to the brachial artery and vein, also allows for direct ability to control bleeding and insert larger sheaths. We did not experience any issue inserting a 9F sheath into the brachial vein or 8.5F sheath into the brachial artery. Access to the brachial artery and vein and closure of the access point took only 15 minutes each time and no additional manual pressure was required to create adequate hemostasis.

Lastly, complications of brachial artery access should also be noted, including vasospasm, thrombosis, thromboembolism distally to the hand, infection, and poor wound healing. Our patient did not experience any of these (and on the contrary benefited from direct visual access under the supervision of the vascular surgery team) and was ambulatory within 1–2 hours of the procedure.

Conclusion

In summary, we present the first reported case of brachial artery and vein access for ablation of VT using an irrigated-tip ablation catheter and integrated imaging (inHEART). Although further study is required to evaluate this technique, we believe that this technique using brachial cutdown may offer several advantages as compared to traditional femoral access and is deserving of further study.