AB-452663-4 LEFT ATRIAL POSTERIOR WALL ABLATION USING PULSED FIELD ABLATION AS ADJUNCTIVE THERAPY DURING RE-DO PROCEDURES AFTER MULTIPLE FAILED PULMONARY VEIN ISOLATIONS USING THERMAL ENERGY

Abstract

Pulmonary vein isolation (PVI) is the cornerstone for patients with atrial fibrillation (AF). Long-term efficacy is limited because of high PV reconnection rates. Ablation targets and strategies beyond PVI in re-do left atrial (LA) procedures have failed to improve outcome. Pulsed field ablation (PFA) has recently been introduced as a novel ablation technology. We report the first experience of re-do PVI with adjunctive LA posterior wall ablation (LAPWA) in patients with multiple failed LA procedures using thermal energy (RF /cryo). After high-density bipolar 3D voltage maps using a pentaspline diagnostic catheter, ablation was performed in conscious sedation using a steerable sheath and a pentaspline over-the-wire basket and flower PFA catheter. After re-do PVI (irrespective of PV status), the pentaspline catheter was visualized in the 3D mapping system. The posterior wall was ablated using the PFA catheter in the flower configuration (Figure). Projected catheter images overlapped approx. 30% between sites across the posterior wall. Per ablation site, 4 applications were administered. Post ablation, 3D voltage maps confirmed complete PVI and LAPWA. Bidirectional PVI was also documented using pacing. Procedural parameters, acute success, in-hospital safety and arrhythmia recurrence were assessed. Between Sept. 2021 and Nov. 2022, 17 patients were enrolled. Mean age was 68±8 years. Time since first AF diagnosis was 72±46 months. Mean number of previous LA procedures was 3±1. Acute PVI and LAPWA were 100% successful. Median procedural time was 160±62 min (including 47±10 min for pre and post mapping). LA dwell time of the PFA catheter was 46±19 min. Fluoroscopy time and dose area product were 24±09 min and 13±13 Gy.cm2. All patients tolerated this approach without procedural interruption. There were no acute or chronic complications. After a follow-up of 163±105 days, 12/17 (71%) patients were free of documented AF, atrial flutter or tachycardia. In patients with multiple failed LA ablations for AF, re-do PVI (irrespective of PV status) and LAPWA using PFA seems to be a safe and feasible approach with promising short-term results. Larger studies are needed to investigate long-term efficacy and safety in this patient group with otherwise very limited therapeutic options.