An unusual presentation of an anomalous left coronary artery arising from the pulmonary artery (ALCAPA) in an adult: anterior papillary muscle rupture causing severe mitral regurgitation.

We describe a 29-year-old male, previously in good health, with no history of angina pectoris and no risk factors for ischemic heart disease presenting with biventricular failure and severe mitral valve regurgitation. There were no signs or serological test results to suggest infective endocarditis. Transthoracic echocardiography (TTE) revealed severe anterior mitral valve prolapse secondary to papillary muscle rupture, severe mitral valve regurgitation, as well as an anterior myocardial wall hypokinesis. Parasternal short-axis view showed an anomalous left coronary artery arising from the pulmonary artery (ALCAPA), which was confirmed on coronary angiography. This is an unusual presentation of ALCAPA in an adult.