Stepwise approach ablation versus pulmonary vein isolation in patients with paroxysmal atrial fibrillation: randomized controlled trial

Background: Pulmonary vein isolation (PVI) is a central procedure for the treatment of paroxysmal atrial fibrillation (PAF). However, in patients with PAF and structural atrial disease, PVI may fail and cause progressive atrial remodeling, often leading to persistent/permanent atrial fibrillation. Objective: We performed a prospective, single-blind, two-center randomized controlled trial compare the efficacy of catheter PVI alone versus PVI plus stepwise approach in achieving SR and non-atrial arrhythmias inducibility patients with PAF refractory to antiarrhythmic therapy. Methods: Participants were randomized to perform a first catheter ablation either through PVI alone or through PVI plus substrate modification based upon stepwise approach. Data were recorded at 3, 6 and 12 months after both ablations. The subjects who experienced AF/AT recurrence were encouraged to repeat ablation using the same technique of the first ablation. Results: 150 subjects were enrolled (mean age 62.8±8.7y; 61.3% males; 69.3% hypertensive; AF mean duration 10.7 months); 75 patients in each group. After 12 months from the first procedure, the patients who were converted to sinus rhythm using PVI plus stepwise ablation ablation showed a significantly lower rate of AF/AT recurrence (26.7%) than those who were treated using PVI alone (46.7%; p<0.001). Similar results were observed among the 52 subjects who underwent a second catheter ablation. Adjusting for several potential confounders, the hazard ratio of 12-month AF/AT recurrence after the first ablation was 0.53 (95% Confidence Interval: 0.30-0.91) for those treated using stepwise ablation. Conclusion: In addition to PVI, the stepwise ablation achieving sinus rhythm and non-atrial arrhythmias inducibility has relevantly enhanced the clinical outcome of PAF control strategy. Registration number: ACTRN12614001231639.