Transcatheter ablation for atrial fibrillation in patients with hypertrophic cardiomyopathy: Long-term results and clinical outcomes

Introduction: Radiofrequency transcatheter ablation (RFCA) for atrial fibrillation (AF) in patients with hypertrophic cardiomyopathy (HCM) has been proven feasible. However, the long-term results of RFCA and its impact on clinical course of HCM are unknown. The aim of this study was to analyse clinical outcomes and long-term efficacy of RFCA in a multicentre cohort of patients with HCM and concomitant AF. Methods: Patients with HCM and AF consecutively undergoing RFCA were included. Ablation failure was defined as recurrence of AF, atrial tachycardia, or flutter lasting more than 3 min and occurring after the blanking period. Results: Overall, 116 patients with symptomatic AF refractory to antiarrhythmic drugs were included. Over a median follow-up of 6.0 years (interquartile range: 3.0–8.9 years) recurrence rate after a single RFCA was 32.3 per 100 patient/years with 26% of patients free from AF relapses at 6-year follow-up. Among patients experiencing AF recurrence, 51 (66%) underwent at least one redo-procedure. The overall recurrence rate considering redo-procedures was 12.6 per 100 patients/years with 53% of patients free from AF relapses at 6 years. At last follow-up, with an average of 1.6 procedures, 67 (61%) patients were in sinus rhythm (SR). Patients remaining in SR showed better functional status compared with those experiencing arrhythmic recurrences (NYHA Class 1.6 ± 0.1 vs. 2.0 ± 0.1, p =.009). Conclusions: RFCA of AF in HCM patients is an effective and safe strategy favoring long-term SR maintenance, reduction of atrial arrhythmic events, and improved functional status. However, most patients need repeat procedures and continuation of antiarrhythmic drugs.