Transformation from persistent atrial fibrillation to paroxysmal type after initial ablation predicts success of repeated ablation.

Background: If transformation from persistent atrial fibrillation (AF) to paroxysmal AF after catheter ablation had impacts on the outcome of repeated ablation was unclear. This study aimed to explore whether the type of recurrent AF after ablation for persistent AF was associated with recurrence after repeated ablation.

Methods And Results: This was a retrospective cohort study. 116 persistent AF patients undergoing the second ablation due to a failed initial ablation were enrolled in our study. Patients with recurrent paroxysmal AF after initial ablation were categorized as Group A (47 patients) while those with recurrent persistent AF were categorized as Group B (69 patients). The study endpoint was defined as any episode of AF, atrial tachyarrhythmia or atrial flutter lasting for >30 s, after the 3 month blanking period following repeated procedure. After 3-72 months (median: 24 months) of follow-up from repeated ablation, 54 (47%) patients suffered from recurrence after repeated ablation. In univariate analyses, Group B suffered a higher risk for recurrence than those in Group A (hazard ratio: 2.05, 95% confidence interval: 1.14-3.70, P = 0.01). Besides recurrent AF type, larger left atrial dimension at repeated procedure and pulmonary vein reconnection also predicted success of repeated ablation. In multivariate analysis, patients in Group B still had a 1.91-fold higher risk for recurrence than those in Group A (HR: 1.91, 95% CI: 1.06-3.44, P = 0.03).

Conclusions: After persistent AF ablation, transformation from persistent AF to paroxysmal AF is independently associated with success of repeat ablation.