Accessory mitral valve leaflet in an adult with coronary artery disease.

Accessory mitral valve leaflet is a very rare cause of left ventricular outflow tract obstruction. We report a patient presenting this cardiac abnormality who undergone cardiac surgery. A 60-year-old man, presented coronary artery disease and moderate left ventricular tract obstruction due to accessory mitral valve leaflet. The accessory mitral valve leaflet had the typical morphology of a parachute-shaped attached partially to the anterior mitral valve leaflet, with chordae tendinae attached to: 1) an accessory papillary muscle inserted at the free-wall closed to the apex; 2) interconnected with the chordae tendinae of the anterior mitral valve leaflet; 3) a second accessory papillary muscle inserted to the interventricular septum. He underwent successful coronary revascularization of 2 vessels and accessory leaflet excision. A review of 21 cases with accessory mitral valve leaflet is reported.