Abstract 11215: Comparative Effectiveness of Alcohol Septal Ablation versus Septal Myectomy on Mortality in Patients With Hypertrophic Cardiomyopathy

Abstract

Introduction: Alcohol septal ablation (ASA) and septal myectomy (SM) are two options of septal reduction therapy (SRT) for patients with medication-resistant symptomatic obstructive hypertrophic cardiomyopathy (HCM). The 2020 AHA/ACC HCM Guideline recommends SM as the first-line choice and ASA as the second-line option to be conducted only if SM is contraindicated or surgical risk is high. However, little is known about the effectiveness of ASA versus SM for HCM on mortality in the real-world settings. Objective: To compare mortality between patients with HCM who underwent ASA and those who had SM using population-based databases. Methods: We identified patients with HCM who underwent an SRT from 2007 through 2014 using the SPARC database — a comprehensive, all-payer claims database that includes record of every inpatient stay and outpatient visit in New York State. We compared mortality at 15, 30, 180, and 360 days after SRT between the ASA group and the SM group (the reference group) using unadjusted analysis, propensity score matching (PSM), and inverse probability weighting (IPW). In the PSM and IPW models, we adjusted for age, sex, race/ethnicity, insurance type, and each item in the Elixhauser Comorbidity Index. Results: We identified 755 patients with HCM who underwent an SRT, including 348 in the ASA group and 407 in the SM group. In the unadjusted analysis, mortality in the ASA group was lower than that in the SM group (crude mortality at 360 days, 3.7% vs. 7.4%; Figure ). Using the PSM method, mortality was lower in the ASA group in the 180-day and 360-day post-SRT periods (adjusted odds ratio [aOR] = 0.31 at 360 days; 95% confidence interval [CI], 0.09-0.93; P = 0.049). The IPW model showed consistent findings with the PSM model (aOR = 0.44 at 360 days; 95% CI, 0.21-0.88; P = 0.02). Conclusions: Patients with HCM who underwent ASA had lower mortality than those who had SM during a 1-year post-SRT period in this population-based study.