The Surgeon’s View of the Left Ventricular Outflow Tract in Congenital Heart Surgery

Left ventricular outflow tract (LVOT) obstruction is a component of many forms of congenital heart disease, including hypertrophic cardiomyopathy, membranous subaortic stenosis, tunnel subaortic stenosis, and outflow tract obstruction related to atrioventricular septal defects. We have gained a particularly extensive experience with the diagnosis and treatment of hypertrophic cardiomyopathy, having performed septal myectomy in over 3,800 patients. In the setting of this review of LVOT obstruction, we use hypertrophic cardiomyopathy as a template by which other pathologies causing LVOT obstruction can be understood. We review important surgical issues in patient selection, diagnostic evaluation, interpretation of imaging, and operative management. To this end, the review focuses on obstructive hypertrophic cardiomyopathy and then broadens to discuss other pathologies causing LVOT obstruction, with important similarities and differences in their management. These other pathologies share some similar presentations and operative techniques, and at times can be confused with hypertrophic cardiomyopathy, but also have important distinctions of which the surgeon should be aware.