Abstract
Coronary artery bypass surgery complicated with mitral regurgitation is significant both as a poor prognosis and because there are diverse treatment options. Ischemic mitral regurgitation (IMR) is not a disease of the mitral valve but of the left ventricle. It is caused mainly by the tethering of leaflets from the chordae tendinae, which is due to local remodeling of the ischemic left ventricle and geometric distortion of the papillary muscles. Annular enlargement plays only a secondary role in the mechanism of IMR. Intraoperative evaluation of MR severity should be performed with caution considering the changes in loading conditions under general anesthesia. There have been many arguments and a lot of controversy among surgeons and cardiologists about the treatment options for IMR, especially for moderate IMR. Some IMR can be relieved after coronary artery bypass surgery (CABG) without the mitral valve procedure, but if it persists after CABG, poor prognosis as well as an additional risk in case of reoperation is implicated. Various kinds of new treatment strategies, including resection of the anterior wall of the myocardium and ‘off-pump’ , or even percutaneous mitral valve plasty, have emerged. As an anesthesiologist, one needs to have a deep understanding of the pathophysiology of IMR and the surgical techniques to treat it.
