Hypoplasia of the posterior mitral valve leaflet: Don’t forget to look beyond the mitral valve

Hypoplasia of the posterior mitral valve leaflet (PMVL) is a very rare finding in adulthood and can coexist with other congenital heart defects. In this image, a transesophageal echocardiography (TOE) carried out on a 59‐year‐old woman with a 2‐month history of dyspnea revealed a hypoplastic PMVL causing severe mitral regurgitation associated with a secundum‐type atrial septal defect (ASD) with left‐to‐right shunting. This case demonstrates how essential 3‐dimensional TOE is for a comprehensive assessment of the mitral valve and to improve the diagnostic accuracy of concomitant congenital heart abnormalities.