Assessing the viability of pulsed field ablation for atrial fibrillation following left atrial appendage occlusion

Abstract Background Pulsed-field ablation (PFA) offers an efficient and safe energy source for pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). In the past, there have been reports of electrical interference with the ablation catheter and the left atrial appendage closure (LAAC) device. We sought to examine the viability of PFA in this patient subset. Methods Consecutive AF patients with prior LAAC who underwent pulsed field (PFA)- based pulmonary vein isolation (PVI) were enrolled. Transesophageal echocardiography was the only imaging performed prior to ablation. PFA was performed using either a 31mm or 35mm pentaspline catheter. The primary outcome was procedural success, defined as acute PVI. Secondarily, freedom from arrhythmia after a 3-month blanking period was assessed in patients with available follow-up data. Results 12 patients were included (33.3% female; 50% paroxysmal AF) with a median age of 77.5 years (IQR 70-81). The majority had received a Amplatzer amulet 7/12, 3/12 a LAmbre and 2/12 a Watchman device. The median procedure time was 35 minutes (IQR 26-45 min). Complete PVI using PFA was feasible in all patients and all PVs (12/12 patients, 44/44 PVs). One patient received an additional ablation of the posterior wall. Electrical interference occurred in one patient using the "flower configuration" for the left superior pulmonary vein (LSPV) so that only the "basked configuration" could be used but resulted in complete PVI nonetheless. Overall, no procedural complications were encountered. Follow-up data was available in 11/12 patients, the average follow-up duration was 335.3 days (SD ±199 days). Arrhythmia recurrence after a 3-month blanking period was found in 4/11 patients at a median of 149.5 days (IQR 119.5 - 405.5). Two patients received repeat ablation whereby 6/8 PVs showed durable isolation. The reconnections were found in the right inferior and right superior pulmonary veins (RIPV and RSPV). Conclusion PFA appears to be feasible in patients with previous LAAC foregoing PVI. Electrical interference using "flower" configuration necessitated a "basket only" approach but resulted in complete PVI. The procedural times were comparable to those described for general AF cohorts without prior LAAC. All PVs with proximity to the LAA showed durable isolation in repeat procedures. In the future, large prospective trials are necessary for further deductibility on the general feasibility of this energy source in this specific patient population.