Functional ischemic mitral regurgitation: myocardial viability as a predictor of postoperative outcome after isolated coronary artery bypass grafting.

Ischemic cardiomyopathy is the most common cause of heart failure in the United States.1 This advanced form of coronary artery disease is marked by diffuse myocardial damage, left ventricular remodeling, and often functional ischemic mitral regurgitation (MR).2 Whether moderate functional ischemic MR in patients with ischemic cardiomyopathy should be addressed with mitral valve repair at the time of coronary artery bypass grafting (CABG) has been debated for a decade.3–7 Arguments against concomitant mitral valve repair are that CABG alone, by decreasing ischemia and improving left ventricular function, often decreases functional ischemic MR, and adding mitral valve repair to CABG increases operative complexity and risk. Arguments favoring concomitant mitral valve repair are that mitral valve repair consistently decreases functional ischemic MR, and CABG alone does not predictably improve postoperative MR.