The higher recurrence rate after catheter ablation in younger patients with atrial fibrillation suggesting different pathophysiology

Background: Young atrial fibrillation (AF) patients have been underrepresented in studies of radiofrequency catheter ablation (RFCA) and the outcome of RFCA has not been widely addressed. We investigated age-related differences in clinical features, the recurrence of atrial tachyarrhythmia, and its predictors of patients who underwent RFCA for AF. Methods: This is a multicenter prospective study of 2799 patients who underwent RFCA for AF in 2017–2020. The patients were divided into two groups — group A (age < 60 years, n = 1269) and group B (age ≥ 60 years, n = 1530) — and a recurrence of any atrial tachyarrhythmia 1 year after RFCA following a 90-day blanking period was compared. Results: The mean age was 51.6 ± 6.7 and 66.8 ± 5.2 years for groups A and B, respectively. Higher body mass index, smaller left atrium, and more prevalent cardiomyopathy and obstructive sleep apnea were observed in group A. Overall, 1-year atrial tachyarrhythmia-free survival was 85.6% and lower in young patients (83.1% in group A vs. 87.7% in group B, log-rank p < 0.01): adjusted hazard ratio (aHR) of recurrence (95% confidence interval (CI)), 1.45 (1.13–1.86) for group A compared to group B (p < 0.01). The association between younger age and higher recurrence was continuously observed in patients under 60 years. Any non-PV ablation was associated with a lower recurrence of atrial tachyarrhythmia in group B (aHR 0.68 (0.47–0.96), p < 0.05), but not in group A. Conclusions: AF patients younger than 60 years had a higher 1-year AF recurrence after RFCA. Young AF patients might have distinctive pathophysiology of AF requiring more integrated management.