We describe a patient who had a coronary arteriovenous fistula (CAVF) and w
hose mitral valve papillary muscle ruptured from chronic ischemia due to a
coronary steal phenomenon. He was treated surgically with ligation of the C
AVF (left circumflex to coronary sinus), coronary artery bypass grafting an
d mitral valve replacement. This is the first report of papillary muscle ru
pture related to CAVF.