First-in-Human Transapical Beating-Heart Septal Myectomy in Patients With Hypertrophic Obstructive Cardiomyopathy

BACKGROUND To simplify surgical septal reduction therapy for hypertrophic obstructive cardiomyopathy (HOCM), we developed a novel transapical beating-heart septal myectomy (TA-BSM) procedure. OBJECTIVES In this study, we sought to evaluate the clinical utility of TA-BSM in a first-in-human trial. METHODS Patients with HOCM were enrolled if they presented with drug-refractory disabling symptoms. TA-BSM was performed via minithoracotomy with the use of our beating-heart myectomy device under echocardiographic guidance, without the use of cardiopulmonary bypass. Repeated resections were performed to tailor the extent of the septal myectomy for sufficient abolishment of left ventricular outflow tract (LVOT) obstruction and mitral regurgitation (MR). The primary outcome measure was procedural success, defined by resting/provoked LVOT gradient <30/50 mm Hg and residual MR grade <= 1(+) (of 4(+)) at 3-month follow-up. RESULTS A total of 47 patients aged 12 to 77 years were enrolled. Of the 46 patients who were followed for 3 months, 42 achieved procedural success. The maximal LVOT gradient decreased from 86 mm Hg (IQR: 67-114 mm Hg) at baseline to 19 mm Hg (IQR: 14-28 mm Hg) at 3 months. MR grade was <= 1(+) in 3 patients at baseline and in 45 patients at 3 months. One patient died on postoperative day 10 owing to device-unrelated reasons. Other major adverse events included 1 delayed ventricular septal perforation and 1 intraoperative left ventricular apical tear. CONCLUSIONS TA-BSM is a safe and efficient minimally invasive procedure for septal reduction of heterogeneous HOCM. Compared with conventional septal myectomy, TA-BSM provides real-time evaluation to guide resection while reducing surgical trauma. (Transapical Beating-Heart Septal Myectomy in Patients With Hypertrophic Obstructive Cardiomyopathy; NCT05332691) (J Am Coll Cardiol 2023;82:575-586) (c) 2023 by the American College of Cardiology Foundation.

Automated summary

This study evaluated the clinical utility of a novel procedure called transapical beating-heart septal myectomy (TA-BSM) for hypertrophic obstructive cardiomyopathy (HOCM). After 3 months of follow-up, 42 out of 46 patients achieved procedural success with significant improvement in left ventricular outflow tract obstruction and mitral regurgitation. In conclusion, TA-BSM is a safe and efficient minimally invasive surgical technique that reduces surgical trauma.