Outcome of alcohol septal ablation in mildly symptomatic patients with hypertrophic obstructive cardiomyopathy: A comparison with medical therapy

Objective The aim of this study was primarily to determine efficacy after alcohol septal ablation (ASA) in mildly symptomatic patients (NYHA class II) with hypertrophic obstructive cardiomyopathy (HOCM), as compared to medical therapy. Methods This retrospective study included 163 mildly symptomatic patients with HOCM evaluated in Beijing Anzhen Hospital between March 2001 and August 2019, consisting of the medical group (n = 105) and the ASA group (n = 58). All-cause mortality and HCM-related death were mainly observed. Results Follow-up was completed in 161 patients and the median follow-up was 6.0 years. Compared to medically treated patients, patients post-ASA had comparable survival free of all-cause mortality (98.3% and 95.1% vs. 93.0% and 83.1% at 5 and 10 years, respectively; p = 0.374). Survival free of HCM-related death was also similar between ASA and medical groups (98.3% and 95.1% vs. 94.3% and 86.2% at 5 and 10 years, respectively; p = 0.608). However, compared to medical therapy, ASA had advantages on the improvement of NYHA class (1.4 +/- 0.6 vs. 2.1 +/- 0.5, p = .000) and lower occurrence of new-onset atrial fibrillation (AF) (7.8% vs. 20.4%, p = .048). Multivariate analysis demonstrated that resting LVOT gradient at the last clinical check-up was an independent predictor of all-cause mortality (HR = 1.021, 95%CI 1.002-1.040, p = .027). Conclusion This registry suggests that mildly symptomatic patients with HOCM treated with ASA have comparable survival to that of medically treated patients, with the improvement of NYHA class and lower occurrence of new-onset AF. All-cause mortality is independently associated with resting LVOT gradient at the last clinical check-up.