Time to recurrence of atrial fibrillation influences outcome following catheter ablation.

Background: Outcome after atrial fibrillation (AF) recurrence after ablation remains poorly characterized.

Objective: To determine whether the time to recurrence of AF after catheter ablation impacts outcome.

Methods: Four hundred thirty-nine consecutive patients with AF after catheter ablation were categorized as early recurrence (E) (3-6 months after ablation; n = 245 patients), late (L) (6-12 months; n = 118), and very late (VL) (>12 months; n = 76). Subsequent AF frequency (defined as rare if ≤ 2 episodes or ≤ 1 cardioversion per 6-month window), response to antiarrhythmic drugs (AADs), and long-term outcome after repeat ablation were evaluated.

Results: Subsequent AF episodes were rare in 9% of E, 42% of L, and 68% of VL groups (P<.001). AF was eliminated with AADs in 19% patients of E, 58% of L, and 72% of VL groups in whom AADs were tried (P<.001). A repeat ablation was performed in 75% patients of E, 59% of L, and 46% of VL recurrence groups (P<.001). With>1-year follow-up after repeat ablation, 49% patients of E, 70% of L, and 89% of VL groups (P<.001) had no or rare AF. In multivariate logistic regression, time to recurrence was an independent predictor of rare AF episodes, better response to AADs, and better outcome after repeat ablation.

Conclusions: In patients with AF after ablation, time to recurrence is a major determinant of outcome. Patients with later recurrences are more likely to have sporadic episodes and respond better to AADs and repeat ablation. These results not only suggest pathophysiologic differences but also have implications for counseling patients regarding anticipated outcome.