RecruitingDevice studyTransventricular Off-pump Mitral Valve RepairThe purpose of this study is to assess the safety and effectiveness (usefulness) of an investigational technique used to repair the mitral valve for patients with mitral regurgitation due to a defective valve leaflet. This procedure is called trans-ventricular off-pump mitral valve repair (TRANSOM) and it repairs the mitral valve by replacing some of the cords that support the mitral valve. This type of repair is minimally-invasive since it is performed through a small incision and avoids making a breast-bone-splitting incision.