Subannular procedures on papillary muscles for secondary mitral valve regurgitation repair

Mitral valve disease is a frequent cause of heart failure and death. The mitral valve must be seen as a complex apparatus made up of valve flaps, annulus, and subannular structures such as tendon cords and papillary muscles (PPM) (dependent on left ventricular [LV] performance). Emerging evidence indicates that the mitral valve is not a passive structure, but even in adult life remains dynamic and accessible for treatment. This concept motivates efforts to reduce the clinical progression of mitral valve disease through early detection and modification of underlying mechanisms. Functional mitral regurgitation is a condition characterized by mitral regurgitation secondary to an ischemic left ventricle or cardiomyopathy. Primarily, the pathology is the result of the perturbation of normal regional LV geometry combined with adverse remodeling. Although the surgical treatment of severe chronic secondary mitral regurgitation (sMR) in patients presenting for coronary artery bypass grafting (CABG) is recommended by the American College of Cardiology/American Heart Association guidelines, the surgical approach remains debated. Many investigators advocated mitral valve restrictive annuloplasty (RA), meanwhile others have suggested mitral valve replacement. Investigators supporting a conservative approach believe that conservation of the continuity between the valve and left ventricle lead to better long‐term results and a reverse in LV remodeling. 2 | EVIDENCE ON ISCHEMIC MITRAL REGURGITATION (iMR)