Pulsed field ablation vs sham ablation to treat atrial fibrillation (the PFA-SHAM trial)

Background Compared with antiarrhythmic drugs, pulmonary vein isolation (PVI) reduces atrial fibrillation (AF) recurrences and AF burden. All but one previous study was unblinded, raising the possibility of a placebo effect of catheter ablation. Objective This study aimed to compare PVI using pulsed field (PF) energy to a sham procedure in patients with symptomatic AF. Methods PFA-SHAM is a single-blind, randomized trial of symptomatic patients with paroxysmal or persistent AF, and an Atrial Fibrillation Effect On Quality-of-Life (AFEQT) questionnaire score ≤50. At enrollment, all patients receive an implantable cardiac monitor, and an electrophysiology study is scheduled 30 days later. After excluding supraventricular tachycardia as a cause of AF, patients are randomized to either sham or PVI using the pentaspline PF ablation catheter. The 2 co-primary outcomes are (1) freedom from recurrent AF, atrial tachycardia, or atrial flutter lasting >30 seconds, assessed as time to first recurrence (post 2-month blanking); and (2) change in quality of life according to the AFEQT score at 6-month post-ablation, compared between groups. Cross-over is permitted for patients with significant symptom worsening according to pre-specified rules. Key secondary outcomes include AF burden at 6 months, and differences in the Hospital Anxiety and Depression Scale, compared between groups. Results Enrollment in the study was initiated in September 2023. As of January 2025, 50 patients have been enrolled. Results are expected by the end of 2025. Conclusion This study compares PVI using PF energy to a sham procedure. The study will assess the effect of PVI on AF recurrences and quality of life. Trial registration number NCT02426944.