The association between late-phase early recurrence within the blanking period after atrial fibrillation catheter ablation and long-term recurrence: Insights from a large-scale multicenter study

Background: The relationship between the timing of the first early recurrence and late recurrence after a single catheter ablation procedure for atrial fibrillation is controversial. Methods: The Efficacy of Short-Term Use of Antiarrhythmic Drugs After Catheter Ablation for Atrial Fibrillation trial followed 2038 patients who underwent radiofrequency catheter ablation for atrial fibrillation. Results: Of the patients, 907 (45%) had early recurrences within 90 days after the initial ablation. We divided these patients into two groups according to the timing of the first early recurrence episode, namely the ER₁ group (early recurrence during the early phase; 0–30 days, n = 814) and ER₂ group (early recurrence during the late phase; 31–90 days, n = 93). Three years after ablation, patients with early recurrences had a significantly lower event-free rate from late recurrences after a 90-day blanking period than patients without early recurrences (36.2% and 74.2%, respectively; log-rank, P < 0.0001). Three years after ablation, the event-free rate was significantly higher in the ER₁ than the ER₂ group (38.3% and 17.1%, respectively; log-rank, P < 0.0001). Moreover, the event-free rate at 3 years in the ER₂ group was extremely low (5.6%) in patient with non-paroxysmal atrial fibrillation. Conclusion: Early recurrences were strongly associated with late recurrences, especially in patients with the first recurrence episode at >1 month within the blanking period after a single ablation procedure. Therefore, these patients should undergo close observation during follow-up, when they had especially with non-paroxysmal atrial fibrillation.