Seminars

Presenter Information.


Abstract: Approximately 7.9 million Americans suffer from heart failure every year with nearly 2.5 million developing ischemic mitral regurgitation (IMR). IMR develops from post infarction left ventricle (LV) remodeling with gross three-dimensional alterations in mitral valve (MV) geometry. These alterations include papillary muscle (PM) displacement and annular dilatation which ultimately lead to restricted leaflet motion and mitral regurgitation (MR). In the past decade, poor survival, low rates of reverse LV remodeling, and recurrent severe MR have been observed in 10-15% of IMR patients who presented with a severely distended LV and undergo restrictive mitral annuloplasty (RMA). In these patients, the severely or progressively displacing PMs hinder RMA’s ability to sustain MV closure and urges the use of adjunct procedures to directly address subvalvular tethering. While adjunct procedures have demonstrated effectiveness, several issues impede our ability to optimally treat these patients. A primary issue relates to identifying patients who will benefit from sole RMA. A secondary issue is the need to understand the geometric mechanisms and limits of IMR procedures to improve and assess their suitability for maintaining coaptation with severe or progressive PM displacement. The ability to directly assess these issues will aid in identifying patients who may benefit from a given treatment while additionally contributing to the improvement and individualization of treatment modalities. Using a multi-center interdisciplinary translational approach, engineered bench and animal models are used to investigate novel surgical techniques for IMR. The hemodynamic function and biomechanics of the MV are quantified under different physiological and patho-physiological conditions, using state-of-the-art instrumentation and imaging procedures. In this approach, clinical and mechanistic insight is gained for not only how to repair the mitral valve, but how to engineer more durable repairs for the large and unsolved clinical burden of IMR.