Standard vs Augmented Ablation of Paroxysmal Atrial Fibrillation for Reduction of Atrial Fibrillation Recurrence

Importance: Recurrent atrial fibrillation (AF) commonly occurs after catheter ablation and is associated with patient morbidity and health care costs. Objective: To evaluate the superiority of an augmented double wide-area circumferential ablation (WACA) compared with a standard single WACA in preventing recurrent atrial arrhythmias (AA) (atrial tachycardia, atrial flutter, or atrial fibrillation [AF]) in patients with paroxysmal AF. Design, Setting, and Participants: This was a pragmatic, multicenter, prospective, randomized, open, blinded end point superiority clinical trial conducted at 10 university-affiliated centers in Canada. The trial enrolled patients 18 years and older with symptomatic paroxysmal AF from March 2015 to May 2017. Analysis took place between January and April 2022. Analyses were intention to treat. Interventions: Patients were randomized (1:1) to receive radiofrequency catheter ablation for pulmonary vein isolation with either a standard single WACA or an augmented double WACA. Main Outcomes and Measures: The primary outcome was AA recurrence between 91 and 365 days postablation. Patients underwent 42 days of ambulatory electrocardiography monitoring after ablation. Secondary outcomes included need for repeated catheter ablation and procedural and safety variables. Results: Of 398 patients, 195 were randomized to the single WACA (control) arm (mean [SD] age, 60.6 [9.3] years; 65 [33.3%] female) and 203 to the double WACA (experimental) arm (mean [SD] age, 61.5 [9.3] years; 66 [32.5%] female). Overall, 52 patients (26.7%) in the single WACA arm and 50 patients (24.6%) in the double WACA arm had recurrent AA at 1 year (relative risk, 0.92; 95% CI, 0.66-1.29; P = .64). Twenty patients (10.3%) in the single WACA arm and 15 patients (7.4%) in the double WACA arm underwent repeated catheter ablation (relative risk, 0.72; 95% CI, 0.38-1.36). Adjudicated serious adverse events occurred in 13 patients (6.7%) in the single WACA arm and 14 patients (6.9%) in the double WACA arm. Conclusions and Relevance: In this randomized clinical trial of patients with paroxysmal AF, additional ablation by performing a double ablation lesion set did not result in improved freedom from recurrent AA compared with a standard single ablation set. Trial Registration: ClinicalTrials.gov Identifier: NCT02150902.