Efficacy of Catheter Ablation for Atrial Fibrillation in Hypertrophic Cardiomyopathy

Background: Atrial fibrillation (AF) is the most common tachyarrhythmia in patients with hypertrophic cardiomyopathy (HCM). The maintenance of sinus rhythm (SR) is sometimes challenging. This study evaluated the clinical outcome of patients with HCM and AF treated with radiofrequency catheter ablation (RFCA). Methods and Results: 17 patients (7 female and aged 61±12 years, mean LAD of 49mm) with paroxysmal (n=12; 71%) or persistent (n=5; 29%) were enrolled. The pulmonary vein isolation was performed in all patients, cavo-tricuspid isthmus ablation in 6, and CFAE ablation in 3. During follow-up of 16±11 months, 10 patients had AF recurrence. After the second procedure in 4 of 10 recurrent patients, 8 in 17 patients (47.1%) were in stable sinus rhythm (SR) with concomitant use of anti-arrhythmic drugs in 13 of 17 patients. In the patients with restoring SR, left atrial diameter (LAD) was significantly smaller compared to those with AF (46±6 vs 52±4; P<0.05). In the patients with LAD <50mm, 7 in 9 patients (88.9%) remained in SR compared with 1 in 8 patients (12.5%) with LAD >50mm (P<0.01). Conclusion: The recurrence of AF was highly observed after RFCA in patients with HCM. The promising clinical result may be provided after RFCA in HCM with smaller LAD (<50mm).