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

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