Ischemic mitral regurgitation: in search of the best treatment for a common condition

Ischemic mitral regurgitation (IMR) is common after myocardial infarction. It results in a significantly increased risk of congestive heart failure and death. The assessment of these patients is challenging as IMR is a dynamic condition and varies in severity under different physiologic conditions, such as physical exertion and changes in left ventricle (LV) contractility. Assessment, therefore, includes both the mitral valve and the LV and needs to be done at rest and under conditions of stress. Treatment of IMR involves optimization of medical therapy for coronary artery disease, coronary artery revascularization, and mitral valve surgery. Most patients have mild IMR and undergo isolated coronary artery revascularization either by percutaneous coronary intervention or coronary artery bypass graft surgery (CABG). In those with severe IMR, mitral valve repair or replacement is indicated, especially if the patient is symptomatic or has impaired LV function or LV dilatation. The optimal treatment of moderate IMR is controversial; mitral valve repair at the time of CABG may be beneficial, but randomized controlled trials are needed. In selected patients with papillary muscle dyssynchrony, cardiac resynchronization therapy may also be helpful.