Prospective evaluation of the acute effectiveness and safety of the circular array pulsed field ablation catheter for atrial fibrillation ablation

Abstract Background The role of posterior wall isolation (PWI) as an adjunct to pulmonary vein isolation (PVI) remains controversial. Thermal ablation has been criticized for its inability to reliably achieve complete posterior wall isolation, as lesion delivery is often prevented for fear of esophageal injury. Pulsed field ablation (PFA) is becoming the mainstay energy source for atrial fibrillation (AF) ablation, and its improved safety profile may allow more effective lesion delivery along the posterior wall. Re-evaluation of the clinical value of PWI in the PFA era is therefore warranted. Objective To determine the safety profile and acute and 6-month procedural success of posterior wall isolation performed with the circular array PFA catheter. Methods All patients undergoing de novo or redo ablation for symptomatic paroxysmal (PAF) or persistent atrial fibrillation (Pers-AF) using the PulseSelect™ circular array PFA catheter between April 2024 and June 2025 were included. Patients received either pulmonary vein isolation (PVI) alone or PVI plus posterior wall isolation (PVI+PWI). Primary endpoints were procedure- or device-related serious adverse events within 30 days, acute procedural success, and 6-month arrhythmia-free survival, defined as the absence of any symptomatic or asymptomatic atrial tachyarrhythmia (AF, atrial flutter and/or atrial tachycardia) lasting ≥30 sec. Results A total of 346 patients underwent catheter ablation (mean age 64.0 ± 11 years, 61% male, 60% PAF), including 42 (12%) redo procedures. PVI alone was performed in 96 patients (28%), PVI + PWI in 248 (72%), and PWI alone in 2 redo cases (0.6%). PVI and PWI was confirmed in all patients with post-procedure mapping. Acute success was achieved in 100% of patients. At 6-months follow-up, the arrhythmia-free survival was 86.9% of PVI only vs 84.0% of PVI + PWI in the PAF patients (p=0.54). In pers-AF, the arrhythmia-free survival was 75.0% vs 74.7% of PVI + PWI patients (p=0.88). Procedural time was slightly longer with PVI+PWI compared with PVI-only (2.0 ± 1.0 vs 1.8 ± 0.4 hours; p=0.06), as was fluoroscopy time (11.5 ± 6.1 vs 7.8 ± 3.3 minutes; p0.001). The total number of PFA applications was higher in the PVI+PWI group (58 ± 16 vs 51 ± 11; p0.001). Complications were infrequent. In the PVI-only group, one patient developed a groin pseudoaneurysm requiring intervention and one developed post-procedural pneumonia. In the PVI+PWI group, there was one pseudoaneurysm requiring intervention, one case of epistaxis, and one case of bronchospasm. Catheter knotting occurred in 3 patients (0.9%) without clinical consequence. No deaths, atrio-esophageal fistula, cerebrovascular events, clinically significant hemolysis, pericardial effusion, or cardiac tamponade were observed. Conclusion Circular array PFA enables safe and effective PVI and PWI with low complication rates. Despite complete posterior wall isolation, the addition of PWI did not improve 6-month arrhythmia outcomes.