Effect of recurrence in the blanking period after thoracoscopic atrial fibrillation ablation on long-term recurrence.

Background: This study evaluated the impact of atrial fibrillation (AF) recurrence during the "blanking period" following thoracoscopic ablation on long-term AF recurrence.

Methods: This prospective observational study enrolled consecutive patients who underwent thoracoscopic AF ablation at our center between 2013 and 2020. Patients were grouped based on AF recurrence during the 3-month blanking period: no recurrence (Group A), early recurrence only (0-7 days, Group B), late recurrence only (8 days-3 months, Group C), or both early and late recurrence (Group D). The primary endpoint was long-term AF recurrence.

Results: We finally analyzed 171 patients (mean age 62.5 ± 8.4 years, 34.5% female). During the blanking period, 118 patients (69.0%) experienced recurrent AF, distributed as follows: 57 in Group B, 35 in Group C, and 26 in Group D. During the median follow-up of 42.3 months (interquartile range: 25.0-60.4 months), post-blanking AF recurrence occurred in 85 patients (49.7%). Group A had the lowest post-blanking recurrence rate. Recurrence in any form (Groups B, C, or D) was associated with a significantly increased risk of long-term AF recurrence compared to Group A (adjusted HR 2.43, 95% CI 1.40-4.24, P = 0.002). Furthermore, Group B had a lower post-blanking recurrence rate (adjusted HR 0.58, 95% CI 0.35-0.97, P = 0.04) compared to Groups C and D.

Conclusions: Late recurrence during the blanking period is a strong predictor of long-term AF recurrence, suggesting the need for closer monitoring and early intervention for patients with late recurrence during the blanking period after thoracoscopic AF ablation.