Minimally Invasive Electro Septal Myectomy for Hypertrophic Obstructive Cardiomyopathy Through a Right Infra-Axillary Incision.

Abstract

This study evaluates the feasibility and short-term outcomes of minimally invasive electro septal myectomy (MESM) for hypertrophic obstructive cardiomyopathy (HOCM) performed through a right infra-axillary incision. A retrospective observational study was conducted at a single center, enrolling consecutive patients diagnosed with HOCM between November 2023 and May 2024 who underwent MESM. The cohort comprised 100 patients (mean age, 51.5 ± 13.4 years; 57.0% men). All procedures were successfully completed using MESM through a 4- to 5-cm right infra-axillary incision, with no conversions to sternotomy. Mean aortic cross-clamp time was 68.6 (SD, 14.9) minutes. Postoperative transthoracic echocardiography revealed a significant reduction in maximum septal thickness from 20.4 (SD, 3.9) mm to 13.2 (SD, 2.0) mm (paired difference, 7.2 [SD, 3.1] mm; 95% CI, 6.3-8.1; P < .001) and left ventricular outflow tract gradient from 85.8 (SD, 28.5) mm Hg to 8.4 (SD, 4.0) mm Hg (paired difference, 77.4 [SD, 29.7] mm Hg; 95% CI, 71.5-83.3; P < .001), with heart rate increasing from 65 (SD, 10) beats/min to 79 (SD, 16) beats/min. Systolic anterior motion was eliminated in all cases, and no severe mitral regurgitation was observed postoperatively. Four patients (4.0%) required permanent pacemaker implantation. No iatrogenic ventricular septal defects or in-hospital mortality occurred. MESM through a right infra-axillary incision represents a feasible, safe, and effective approach for HOCM management, offering significant hemodynamic improvement with minimal complications.