Background: Pulsed field ablation (PFA) is an emerging energy source for catheter ablation. The efficacy and safety of a pentaspline PFA catheter (FARAWAVE) for pulmonary vein isolation have been demonstrated in large multicentric studies. The unique tissue selectiveness of PFA, compared to thermal energy sources, may enable safe and efficient ablation of left and right atrial myocardium beyond pulmonary vein isolation (PVI).

Methods: In our centre, the pentaspline PFA catheter was utilized for atrial ablation beyond PVI in selected cases. These procedures can be categorized into three groups: (1) patients with distinct anatomical features, such as persistent left superior vena cava (PLSVC) or a very large left atrial diameter; (2) patients with atrial fibrillation or atrial tachycardia (AT) who had one or more failed previous ablation attempts; (3) patients who experienced organized atrial tachycardia (AT) after PFA PVI during the procedure. We retrospectively assessed procedural details, safety, and acute efficacy of these procedures.

Results: We reviewed a total of 39 procedures. Among the cases, 43.6% (17/39) had persistent AF, 30.8% (12/39) had organized atrial tachycardia and 23.1% (10/39) had paroxysmal AF. In 56.4% (22/39) of the cases, it was the patients' first ablation for atrial tachyarrhythmia, while the remaining 43.6% (17/39) underwent their second, third or fourth procedure. The procedures consisted of 44 specific lesion sets, including 22 left atrial posterior wall isolations, 6 left atrial anterior lines, 5 mitral isthmus ablations, 4 persistent left superior vena cava isolations, 3 right atrial appendage ablations, 2 cavotricuspid isthmus ablations, 1 left atrial appendage isolation, and 1 superior vena cava isolation. No major complications occurred during the procedures. The mean procedure time was 46.7 ± 23.4 minutes and the mean fluoroscopy time was 9.2 ± 4.6 minutes. Intraprocedural efficacy was high, with 95.5% (42/44) successful lesion sets. Two ablations, consisting of one anterior line and one mitral isthmus ablation, did not result in a complete bidirectional block.

Conclusion: Our experience supports the assumption that PFA, with its tissue selectiveness, can be safely used for atrial ablation beyond pulmonary vein isolation and demonstrates a high acute intraprocedural efficacy. This makes it an interesting energy source for cases where previous ablation has failed or when a challenging procedure, such as persistent left superior vena cava isolation, is anticipated. Evaluation of long-term clinical follow-up and assessment of lesion durability should be considered in future studies.