Abstract
A tri-leaflet mitral valve (MV) is an extremely rare phenomenon, often associated with significant mitral regurgitation (MR). It may represent a phenotypic expression of hypertrophic obstructive cardiomyopathy (HOCM). We present the case of a 69-year-old woman with HOCM, a tri-leaflet MV, and systolic anterior motion (SAM)-induced severe MR. Despite receiving optimal medical therapy, her refractory symptoms and significant MR prompted surgical consideration. The patient underwent surgical myectomy, resulting in improvement of left ventricular outflow tract obstruction, SAM-induced MR, and symptomatic relief. This case illustrates a unique presentation of HOCM with a tri-leaflet MV and significant MR, successfully managed with a tailored surgical myectomy. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12055-024-01871-x.