Clinical experiences of surgical repair for mitral regurgitation secondary to papillary muscle rupture complicating acute myocardial infarction.

Mitral regurgitation secondary to ischemic heart disease carries a significant mortality even after emergency open heart surgery. From 1993 to 1997, four patients were operated on for ischemic mitral regurgitation secondary to papillary muscle rupture. These patients were between 58 and 69 years of age and all were in class III or IV of the New York Heart Association Classification. The responsible infarction area was located in the lateral wall in 2 patients, and inferior in others. The interval between the onset of acute myocardial infarction and the appearance of mitral regurgitation was from 1 to 10 days. Three patients had partial rupture (defined as only one or several heads of papillary muscle ruptured), and one had total papillary muscle rupture. Primary mitral plasty was performed in 3 patients, including 1 patient who had undergone patch closure of ventricular septal perforation at the onset of acute myocardial infarction. Mitral plasty combined with coronary artery bypass grafting was performed in 1 patient. Only one case, who had total papillary muscle rupture, required reoperation for recurrence of mitral regurgitation. We suggest that even in the case of ischemic mitral regurgitation, when a papillary muscle rupture is partial, mitral repair is performed because of its potential for improving therapeutic results.