The Papillary Muscle Approximation Provide Stability of Mitral Valve Repair for Ischemic Mitral Regurgitation

Ischemic mitral regurgitation develops in 10-50% of patients after myocardial infarction. Among several surgical procedures, mitral ring annuloplasty has been the method of choice for a considerable period. However, mitral regurgitation recurrence after surgery has a reported occurrence that ranges from 5% to 58%. Careful consideration of the mechanisms underlying recurrence of mitral regurgitation after annuloplasty might explain the unsatisfactory outcomes. The pathophysiology of IMR is complex and results from the imbalance between closing and tethering forces acting on the mitral valve. Enlargement of the left ventricular chamber, and displacement of papillary muscles in apical and lateral direction increase the tethering forces. Left ventricular and papillary muscle dyssynchrony, reduced myocardial contractility decrease closing forces, which lead to impaired leaflet coaptation and appearance of mitral regurgitation. Thus, treatment of mitral insufficiency requires an integrated approach affecting all units of the pathogenesis of MR recurrence.

Recent publications show that an adjunctive subvalvular repair during mitral annuloplasty for secondary mitral regurgitation effective in preventing recurrent regurgitation. One of these procedures is the papillary muscles approximation. However, the safety and the positive impact of this method are still in doubt. This study is conducted to identify the positive qualities and safety of this technique.