Hypoplasia of the posterior mitral valve leaflet detected in late adulthood

A 76-year-old male with a pacemaker presented with acute pulmonary oedema requiring invasive mechanical ventilation. Transthoracic echocardiography (TTE) revealed a partially flail anterior mitral leaflet, severe mitral regurgitation (MR), and pulmonary hypertension, not present on previous TTEs. Transoesophageal echocardiography (TEE) demonstrated an elongated anterior mitral valve leaflet (AMVL) with a flail A2...