Outcomes of extended septal myectomy for hypertrophic obstructive cardiomyopathy in an Asian cohort

BackgroundHypertrophic obstructive cardiomyopathy (HOCM) is a complex cardiac disorder often treated with septal myectomy, the gold-standard surgical intervention that improves symptoms and survival. Long-term outcome data with paired echocardiographic follow-up from the Indian subcontinent remain limited.MethodsThis was a retrospective cohort study of consecutive patients undergoing extended septal myectomy for HOCM at a single tertiary referral centre between 2014 and 2024, analysed from a prospectively maintained clinical registry. Demographic, clinical, echocardiographic, operative and follow-up data were analysed. Survival was estimated by the Kaplan-Meier method.ResultsA total of 399 patients underwent extended septal myectomy (mean age 41.2 ± 16.5 years; 282/399, 70.7% male; 46/399, 11.5% aged under 18 years). Septal hypertrophy was mainly mid-septal (255/399, 63.9%), with basal (110/399, 27.6%) and apical (34/399, 8.5%) involvement. Myectomy was isolated in 247/399 patients (61.9%) and combined with a concomitant procedure in 152/399 (38.1%); 15/399 patients (3.8%) had undergone a prior cardiac intervention, including alcohol septal ablation in 1/399 (0.3%) and previous cardiac surgery in 9/399 (2.3%). In-hospital mortality was 6/399 (1.5%). Mean follow-up was 5.4 ± 3.1 years, and median follow-up was 5.9 years (interquartile range 2.5-6.7); vital status was complete for all patients. Survival was 98.1% (95% CI 96.7-99.5) at 5 years and 95.9% (95% CI 92.7-99.0) at 10 years.ConclusionsExtended septal myectomy provides excellent structural, functional, and survival outcomes, comparable to leading centres. It should remain the preferred surgical treatment for symptomatic HOCM.