Thoracoscopic trans-mitral myectomy for hypertrophic obstructive cardiomyopathy: a retrospective single-centre study

Abstract

OBJECTIVES Transaortic myectomy is a common procedure for patients with hypertrophic obstructive cardiomyopathy (HOCM). Thoracoscopic trans-mitral myectomy has been described in a few small-sample studies and has been recommended as preferable. We herein report our clinical outcomes using the thoracoscopic trans-mitral approach with 76 patients. METHODS A retrospective single-center analysis of the safety and efficacy of thoracoscopic trans-mitral myectomy by comparing the clinical outcomes with that of transaortic myectomy. RESULTS Between April 2019 and October 2021, 132 patients underwent either a transaortic (n = 56) or a thoracoscopic trans-mitral myectomy (n = 76). Compared with those in the transaortic group, patients in the trans-mitral group were more likely to be weaned off the ventilator within 24 h after surgery (80.3% vs 60.7%, P < 0.05) and to require a shorter duration of ventilation [29.01(43.91) h vs 51.12(94.96), P = 0.08] and lower transfusion rate (26.3% vs 48.2%, P < 0.05). The in-hospital mortality rate of the transaortic and trans-mitral groups was 3.6% (n = 2) and 1.3% (n = 1), respectively. No significant inter-group differences were observed regarding in-hospital mortality, the incidence of low cardiac output syndrome, or permanent pacemaker implantations. In the trans-mitral group, the thickness of the interventricular septum was significantly reduced postoperatively, with resultant relief of the left ventricular outflow tract obstruction [89.37(27.5) mmHg vs 10.51(0.65) mmHg, P < 0.01]. Transaortic myectomy also resulted in a significant reduction in left ventricular outflow tract gradient [90.41(33.31) mmHg vs 11.35(9.43) mmHg, P < 0.01]. And the incidence of residual SAM of the trans-mitral group and the transaortic group were 2.67% and 1.9%, respectively. CONCLUSIONS The thoracoscopic trans-mitral approach provides excellent exposure to the septum and anomalies of the mitral valve and papillary muscle. It relieves obstruction effectively, without increasing the incidence of major complications.

Management of the mitral valve in thoracoscopic trans-mitral myectomy for hypertrophic obstructive cardiomyopathy

“…The TTM surgery for HOCM was performed as described in our previous study. 11 , 12 In brief, the surgical preparation and exposure are similar to that for total thoracoscopic MV surgery. Before myectomy, transesophageal echocardiography (TEE) and thoracoscopy were applied to identify any intrinsic MV disease (eg, rheumatic valve disease; Barlow disease; leaflet calcification, contracture, prolapse, or ruptured chordae with consequent flail leaflet; degenerative lesions).…”

Anomalous papillary muscle insertion into the mitral valve leaflet in hypertrophic obstructive cardiomyopathy: a lip nevus sign in echocardiography

“…Symptomatic patients with HOCM who were tolerant to medication and had ≥50 mmHg of left ventricular outflow tract gradient (LVOTG) received surgical treatment as recommended by the management guideline for HOCM ( 7 ). Extended myectomy, via the transaortic or transmitral approach, was performed as described previously ( 8 ). Surgical strategies for mitral valves and APMs include mitral valve replacement, papillary muscle dissociation and excision, and other mitral repair techniques, as needed.…”

Multimodality Cardiovascular Imaging for Totally Video-Guided Thorascopic Cardiac Surgery

“…Cardiac surgeons have acquired specialized skills to conduct cardiac procedures under the guidance of a video field projected from high-resolution transition signals with thoracoscopy with and without cardiopulmonary bypass (CPB). The disease spectrums covered by this technique range from mitral or tricuspid valve dysfunction, congenital heart defects such as atrial septum defects (ASD), incomplete endocardial cushion defects, partial anomalous pulmonary venous drainage, cardiac tumors, and hypertrophic obstructive cardiomyopathy (HOCM) with left ventricular outflow tract obstruction [ 2 ]. This minimal port-access approach has been successfully applied to rescue technical complications including occluder device failure and migration during percutaneous closure of ASDs [ 3 ], failed mitral valve clip device implantation [ 4 ] and paravalvular leakage after primary mitral valve replacement [ 5 ].…”