Insight into early recurrences after pulsed-field ablation of atrial fibrillation

Abstract Background Several studies have shown a significant association between early and late recurrence following ablation procedures for atrial fibrillation (AF). However, factors contributing to early recurrence after AF ablation, particularly with pulsed-field ablation (PFA), remain poorly understood. Purpose This study aimed to evaluate the significance of early recurrence and identify factors associated with its occurrence, with a focus on predicting late recurrence in AF patients treated with PFA. Methods A total of 662 consecutive patients, referred for their first paroxysmal or persistent AF ablation, underwent the procedure using the FARAPULSE PFA system across 10 Italian centers were included. Early recurrence was defined as atrial arrhythmia of >30-second duration during the 3-month blanking period, and any recurrence beyond 3 months was considered as late recurrence. Results Of the 662 patients, 53 (8.0%) experienced early recurrence within the first 3 months of follow-up (median time to recurrence: 55[22–76] days). Specifically, 17 (32.1%) had recurrence within the first 30 days, 14 (26.4%) between 31 and 60 days, and 22 (41.5%) between 61 and 90 days post-ablation. In multivariate logistic analysis adjusted for baseline confounders, an extended lesion set beyond pulmonary vein isolation (PVI) (HR=2.91, 95% CI: 1.47–5.76, p=0.0023) and larger left atrial volume index (HR=1.03, 95% CI: 1.01–1.05, p=0.0083) were significantly associated with early arrhythmia recurrence. Over a median follow-up of 365[244–408] days, 122 (18.4%) patients experienced late recurrences (median time to recurrence: 188[133–242] days). Factors independently associated with late recurrence included age (HR=1.03, 95% CI: 1.01–1.06, p=0.0071), sleep apnea (HR=3.02, 95% CI: 1.42–6.39, p=0.0041), and early recurrence (HR=3.91, 95% CI: 2.20–6.94, p<0.0001). In patients with paroxysmal AF (n=468, 70.7%) and those undergoing PVI alone (n=512, 77.3%), early recurrences were noted in 30 (6.4%) and 31 (6.1%) cases, respectively, while late recurrences occurred in 86 (18.4%) and 88 (17.2%) cases, respectively. Early recurrence significantly increased the likelihood of late recurrence in both groups (40.0% vs. 16.9%, p<0.0001 for paroxysmal AF; 38.7% vs. 15.8%, p=0.0027 for PVI-only patients). Conclusion In this cohort of AF patients undergoing PFA, an extended lesion set beyond PVI and larger left atrial volume were associated with early recurrence. Moreover, early recurrence significantly increased the risk of late recurrence, highlighting its potential as a predictive marker for long-term outcomes.