Moderate Mitral Regurgitation in CABG Patients

Background: The presence of a mild to moderate ischemic mitral regurgitation (IMR) results in a significantly reduced long-term survival and increased hospitalizations for heart-failure. The benefit of adding mitral valve surgery to coronary artery by-pass surgery (CABG) is well documented in the combination of coronary artery disease and severe MR. On the other hand, it is clinical practice to refrain from repairing the mitral valve in those CABG cases where the IMR is mild to moderate. However, there are no conclusive data available to support this principle. The existing studies are small, retrospective, and the results contradictive. The need for a prospective randomized trial has frequently been proposed and discussed, however, to the best of our knowledge, such a study has not yet commenced. Study design: The Moderate Mitral Regurgitation In Patients Undergoing CABG (MoMIC) Trial is the first international multi-center, large-scale study to clarify whether moderate IMR in CABG patients should be corrected. A total of 550 CABG patients with moderate IMR are to be randomized to either CABG alone or CABG plus mitral valve correction. Implication: If correction of moderate MR in CABG patients is the superior strategy, this should be offered to all patients in this entity.