Anatomic approach with bipolar ablation between the left pulmonic cusp and left ventricular outflow tract for left ventricular summit arrhythmias

Abstract

Radiofrequency catheter ablation (RFCA) of ventricular arrhythmias (VAs) arising from the inaccessible basal region of the left ventricular summit (LVS) is challenging due to proximity to coronary vessels, epicardial fat, and poor radiofrequency (RF) delivery within the distal coronary venous system. The purpose of this study was to describe the outcomes of an anatomic approach to inaccessible LVS-VAs using bipolar radiofrequency (Bi-RFCA) delivered from the anatomically adjacent left pulmonic cusp (LPC) to the opposite left ventricular outflow tract (LVOT). Patients from 3 centers who had undergone Bi-RFCA for inaccessible LVS-VAs refractory to conventional RFCA using an anatomic approach targeting the adjacent LPC (reversed U approach) with catheter tip pointing inferiorly within the LPC and LVOT were reviewed. Seven patients (age 59 ± 12 years; 3 women) underwent Bi-RF from the LPC to the LVOT for LVS-VAs after ≥1 failed conventional RFCA. Bi-RFCA (power 36 ± 7 W; duration 333 ± 107 seconds) resulted in VA suppression in 5 of 7 patients. In 2 cases, Bi-RFCA was successfully performed using dextrose 5% in water. No complications occurred. After mean follow-up of 14 ± 6 months, no recurrent VT was documented in 2 of 2 patients with baseline VT. Mean 84% reduction in premature ventricular contraction (PVC) burden (31% ± 13% vs 4% ± 5% PVCs per day; P = .0027) was documented in the other patients. In patients with LVS-VAs arising from the inaccessible region and refractory to conventional RFCA, an anatomic approach using Bi-RFCA from the LPC and opposite LVOT is an effective alternative approach.