Very late recurrence after atrial fibrillation ablation: Clinical characteristics and pulmonary vein reconnection...

Delayed recurrence of atrial fibrillation (AF) after index ablation is increasingly recognized, but its clinical and procedural phenotypes remain poorly described.

This study aimed to characterize patients undergoing very late redo (VLR) AF ablation (>5 years after prior ablation) and compare pulmonary vein (PV) findings across redo interval groups.

Consecutive patients undergoing redo AF ablation at Alfred Health and Cabrini Health (2007-2025) were included and grouped by redo interval (<1 year, 1-5 years, >5 years).

Of the 596 patients undergoing redo AF ablation, 71 (12%) underwent VLR AF ablation (median redo interval, 7.1 years [interquartile range [IQR], 5.9-8.2]). These patients had a mean age of 62.1 years; 72% were male, and the median congestive heart failure, hypertension, age, diabetes mellitus, prior stroke or transient ischemic attackor thromboembolism, vascular disease, age, sex category score was 2 (IQR, 1-3), with 57.7% having paroxysmal AF at the redo procedure. PV reconnection (any) was less likely with increasing time from index PV isolation: at <1 year, 80.1% (189/236); 1-5 years, 65.1% (188/289); >5 years, 49.3% (35/71); P < .001. Each additional year from index to redo ablation was associated with an 8.6% lower expected number of reconnected PVs (rate ratio, 0.91, 95% CI, 0.88-0.95; P < .001). In total, 32/71 (45%) of the patients undergoing VLR AF ablation developed recurrent AF at a median follow-up of 243 days (IQR, 103-1097) from the repeat procedure.

The likelihood of PV reconnection declines significantly with increasing time to redo AF ablation; the majority of patients >5 years have enduring PV isolation. This suggests a greater contribution from non-PV triggers and/or AF substrate in this cohort.