Abstract 18607: Intra-ventricular Papillary Muscle Banding vs. Undersized Mitral Annuloplasty to Treat Ischemic Mitral Regurgitation in a Chronic Swine Model

Introduction: Intra-ventricular papillary muscle banding (PMB), is a new mitral repair technique for ischemic mitral regurgitation (IMR), which reduces lateral distance between the two muscles to relieve leaflet tethering (Fig A). In this study, we compared the hemodynamic efficacy of PMB against undersized mitral annuloplasty (UMA) and the combination of PMB and UMA, in a chronic swine IMR model. Methods: Six swine were induced with chronic IMR via percutaneous infarction of the postero-lateral wall of the left ventricle(LV), and followed to 6 weeks to develop >3+ IMR. At 6 weeks, via a left atriotomy an adjustable PMB externalized through the LV wall, and an adjustable UMA suture externalized through the anterior annulus were implanted (Fig B1,B2). The animals were weaned from bypass, and physiological swine hemodynamics of 90/65 mm Hg were achieved at 75 bpm. PMB was done such that 50% reduction in the lateral distance between the muscles was achieved, and UMA reduced septal-lateral annular dimension t...