Application of mini-invasive surgical instruments in transaortic myectomy for hypertrophic obstructive cardiomyopathy: A single-center experience with 168 cases

Abstract

Background: Septal myectomy has been a standard treatment option for patients with hypertrophic obstructive cardiomyopathy (HOCM) and drug refractory symptoms. However, there are only a few experienced myectomy centers in the world so far, mainly because of high technical difficulty of myectomy. From our clinical experience, the use of the mini-invasive surgical instruments during myectomy may be beneficial to reduce the technical difficulty. This study reports the preliminary experience regarding transaortic septal myectomy using mini-invasive surgical instruments for the treatment of patients with HOCM and drug refractory symptoms, and evaluates the early results following myectomy.Methods Between March 2016 and March 2019, consecutive HOCM patients were included in this analysis who underwent isolated transaortic septal myectomy using the mini-invasive surgical instruments. Intraoperative, in-hospital and follow-up results were analyzed.Results A total of 168 eligible patients (83 males, mean 56.8 ± 12.3 years) were included. Midventricular obstruction was recorded in 7 (4.2%) patients. All included patients underwent transaortic septal myectomy with a mean aortic cross-clamping time of 36.0 ± 8.1 minutes. Nine (5.4%) patients received repeat aortic cross-clamping during surgery. Surgical mortality was 0.6%. Five (3.0%) patients developed complete atrioventricular block and required permanent pacemaker implantation. The median follow-up time was 6 months. No follow-up deaths occurred with a significant improvement in New York Heart Association functional status. The maximum gradients decreased sharply from the preoperative value (11.6 ± 7.4 mmHg vs. 94.4 ± 2 2.6 mmHg, p<0.001). The median degree of mitral regurgitation fell to 1.0 (vs. 3.0 preoperatively, p<0.001) with a significant reduction in the proportion of moderate or more regurgitation (1.2% vs. 57.7%, p<0.001).Conclusions The use of the mini-invasive surgical instruments may be beneficial to reduce the technical difficulty of transaortic septal myectomy procedure. Transaortic septal myectomy using the mini-invasive surgical instruments may be associated with favorable results.