Introduction: Pulsed field ablation (PFA) is a novel nonthermal ablation approach using rapid electrical pulses to cause cardiac cell apoptosis via electroporation. Our study aims to investigate the feasibility and safety of PFA for persistent atrial fibrillation (PeAF). Methods: 32 consecutive patients diagnosed with PeAF were enrolled in our study. All patients underwent PFA treatment using the strategy including pulmonary vein isolation (PVI), left atrial posterior wall (LAPW) isolation, cavotricuspid isthmus (CTI) block, and mitral isthmus (MI) block. Acute and follow-up procedure outcomes were evaluated, and adverse events related to the ablation procedure were also observed. Results: One-year survival free from atrial tachyarrhythmia post-ablation was 65.6%. Acute success rates for PVI, LAPW isolation, CTI block, and MI block were 100%, 100%, 96.9%, and 81.3%, respectively. Eleven cases (34.4%) experienced atrial tachyarrhythmia recurrence, with 8 cases being atrial fibrillation recurrence and 3 cases being atrial flutter recurrence. Three patients underwent repeat ablation. Minor complications were encountered in 4 patients with asymptomatic cerebral lesions. Vagal responses were commonly observed during the procedure. No severe coronary vasospasm or severe haemolysis occurred in our cohort. Conclusion: PFA with the strategy including PVI, LAPW isolation, CTI block, and MI block is feasible, safe, and associated with a high rate of freedom from atrial tachyarrhythmia recurrence at 1 year in patients with PeAF.

Introduction: The safety and effectiveness of catheter ablation in patients with atrial fibrillation (AF) who underwent mechanical mitral valve replacement (MVR) have been reported. However, the impacts of different types of mitral valves on the safety and effectiveness of catheter ablation in patients with AF who underwent MVR have not been elucidated. Methods and results: From 2015 to 2021, 17,496 patients underwent catheter ablation of AF for the first time in Beijing Anzhen Hospital were screened. The inclusion criteria were (1) aged 18 years or older; (2) diagnosed with AF; (3) history of mitral valve replacement. The exclusion criteria were a history of catheter ablation, surgical maze procedure, left atrial appendage closure or resection. A total of 68 patients were enrolled in the study. The patients were divided into two groups: the bioprosthetic MVR group (n=12) and the mechanical MVR group(n=58). The size of the left atrial was larger (49.5mm vs. 46.0mm, p<0.05), the thickness of the left interventricular septum was larger (11.0mm vs. 10.0mm, p<0.05), and the mitral ring area was smaller (2.3mm2 vs. 2.6mm2, p<0.05) for the bioprosthetic MVR group than the mechanical MVR group. During 23.4 (6.1, 36.5) months of follow-up, the incidence of the endpoint events was not significantly different between the two groups (33.3% vs. 30.4%, log-rank p=0.48). There were 2 cases (3.4%) of pseudoaneurysm and 1 case of acute cerebral infarction in the mechanical MVR group. No complication was observed in the bioprosthetic MVR group. No significant clinical bleeding events were observed in the bioprosthetic group while eight patients in the mechanical MVR groups had bleeding events (p=0.368) during the follow-up. Conclusion: The safety and effectiveness of catheter ablation of AF were comparable between the patients with mechanical MVR and bioprosthetic MVR.