Atrioventricular node ablation is an effective management strategy for atrial fibrillation in patients with hypertrophic cardiomyopathy

BACKGROUND: Atrial fibrillation (AF) is common in hypertrophic cardiomyopathy (HCM) patients and can be challenging to manage. Atrioventricular node (AVN) ablation may be an effective management strategy for AF in these patients. OBJECTIVE: Assess the efficacy of AVN ablation in HCM patients who have failed medical therapy and/or catheter ablation for AF. METHODS: Multi-centre study with retrospective analysis of a prospectively collated HCM registry. AVN ablation patients were identified. Baseline characteristics, device and procedural indication were collected. Symptoms defined by NYHA and EHRA classification and echocardiographic findings during follow-up were assessed. RESULTS: Fifty-nine patients were included. Indications for AVN ablation were: 6 (10.2%) inappropriate ICD shock, 35 (59.3%) ineffective rate control and 18 (30.5%) to regularize rhythm to improve symptoms. During post-AVN ablation follow-up of (79.4±61.1 months), left ventricular ejection fraction (LVEF) remained stable (pre-LVEF 48.9±12.4%, post-LVEF 49.8±10.9%, p=0.68) even in those without a CRT device (pre-LVEF 54.3±8.0% vs post-LVEF 53.8±8.0%=0.65). Forty-nine (83.1%) patients reported an improvement in symptoms regardless of AF type (17/21, 81.0% paroxysmal vs. 32/38, 84.2% persistent AF; p=1.00), presence of baseline LV impairment (22/26, 84.6% LVEF≤50% vs. 27/33, 81.8% LVEF≥50%; p=1.00) or CRT device (27/32, 84.4% CRT vs. 22/27, 81.5% no CRT; p=1.0). Symptoms improved in 16 (89%) patients who underwent AVN ablation to regularize rhythm. CONCLUSION: AVN ablation improved symptoms without impacting LV function in a majority of the patients. AVN ablation is suggestive to be an effective and safe management approach for AF in HCM and should be further evaluated in larger prospective studies