Late surgical results for ischemic mitral regurgitation. Role of wall motion score and severity of regurgitation

The indication for concomitant valve operations for ischemic mitral regurgitation is examined in 120 consecutive patients with regurgitation who had coronary bypass. Ischemic mitral regurgitation was mild in 56%, moderate in 18%, and severe in 27%. Compared with patients without mitral regurgitation who underwent coronary bypass, significantly more patients with regurgitation had cardiomegaly (31% versus 5%), left heart failure (42% versus 6%), and abnormal wall motion scores (71% versus 42%). Eighty-three patients (69%) with ischemic mitral regurgitation had coronary bypass alone and 37 (31%) also had a valve operation. All patients with mild ischemic mitral regurgitation were treated by coronary bypass alone, as compared to 67% with moderate and 6% with severe regurgitation. Operative mortalities for mild, moderate, and severe ischemic mitral regurgitation were 4%, 10%, and 38%, respectively; 5 year survival rates were 82%, 60%, and 48%, respectively. Other significant determinants of survival were wall motion score, shock, cardiomegaly, left heart failure, and acute and multiple myocardial infarctions. Patients with mild ischemic mitral regurgitation and a low wall motion score (n = 40) had a 5 year survival rate of 94%. For patients with either moderate/severe regurgitation (n = 27) or a high wall motion score (n = 25), but not both, the 5 year survival rate was 70%. In 20 patients with both a high wall motion score and moderate/severe regurgitation, it was 33%. An additive detrimental effect is apparent. The change from mild to moderate/severe ischemic mitral regurgitation was equivalent to an increase of about 8 wall motion score units in terms of effect on survival. Ischemic mitral regurgitation is a powerful additive risk factor to wall motion score in coronary bypass. Mild regurgitation is best managed by coronary bypass alone. If regurgitation is moderate, it may still be possible to avoid a valve operation and have acceptable results. Severe ischemic mitral regurgitation usually necessitates coronary bypass and a mitral valve operation.