Surgical treatment of ischemic mitral valve regurgitation.

In cases of old myocardial infarction, the presence of mitral valve regurgitation is one of the predicting factors of long-term prognosis. The mechanism of ischemic mitral regurgitation consists of mitral annular dilatation, left ventricular (LV) dilatation followed by tethering of the mitral valve, etc. Since long-term prognosis of the patients in whom the degree of mitral valve regurgitation is 2+ or more is typically poor, the mitral valve procedure should be considered at the time of coronary artery bypass grafting (CABG) or more. In this type of surgery, the treatment essentially involves the use of an artificial ring implantation as the basic technique. In the chronic stage, a significant degree of mitral regurgitation persists in approximately 20% of the cases if they have been treated by ring annuloplasty alone. Additional surgical procedures that reduce or eradicate the tethering are essential for the control of the regurgitation completely in cases with strong tethering. We recently employed two new surgical techniques, namely, cutting the secondary chordae to the anterior mitral valve leaflet and the anterior and posterior papillary muscle reapproximation. The surgical results of the acute phase appear to be promising; however, the long-term results of such new methods are yet to be determined. If the mitral valve regurgitation cannot be controlled even by various operative techniques of mitral valve repair, mitral valve replacement should be considered. This is because the long-term survival rate of the suboptimal repair surgical patients is lower when compared with that of mitral valve replacement patients.