Minimally Invasive Electro Septal Myectomy for Hypertrophic Obstructive Cardiomyopathy via Right Infra-Axillary Incision

Z. Dong, S. Wang, Z. Liu, C. Wu, E. Han, C. Luo, W. Chen, F. Mei, X. Lu, Z. Hu, B. Zhou, Y. Cui
Zhejiang Provincial People's Hospital (Affiliated People's Hospital), Hangzhou, Zhejiang

Purpose: This study aimed to assess the outcomes of minimally invasive electro septal myectomy (MESM) for hypertrophic obstructive cardiomyopathy (HOCM) performed through a right infra-axillary incision.

Methods: We conducted a retrospective observational study at a single center, including patients diagnosed with HOCM between November 2023 and May 2024. All procedures were performed via a right infra-axillary incision (4-5 cm).

Results: The cohort consisted of 100 patients (mean age 51.5 ± 13.4 years; 57.0% male). All procedures were successfully completed using MESM via a 4-5 cm right infra-axillary incision, without conversion to sternotomy. The average cross-clamp time was 68.6±14.9 minutes. Transthoracic echocardiography demonstrated a significant reduction in maximum septal thickness from 20.4±3.9 mm to 13.2±2.0 mm (paired difference [PD]: 7.2±3.1 mm; 95% CI: 6.3-8.1; p＜0.001), and in left ventricular outflow tract gradient from 85.8±28.5 mmHg to 8.4±4.0 mmHg (real-time heart rate from 65±10 to 79±16 beats per minute) (PD: 80.0±29.7 mmHg; 95% CI: 69.3-85.6; p＜0.001). The systolic anterior motion phenomenon was completely eliminated, with no severe mitral regurgitation observed postoperatively. Four (4.0%) patients required permanent pacemaker implantation. No iatrogenic ventricular septal defects and in-hospital mortality occurred.

Conclusion: This novel method of minimally invasive electro septal myectomy for hypertrophic obstructive cardiomyopathy is feasible and safe.

Identify the source of the funding for this research project: no