New Perspective on Pathophysiology and Management of Functional Mitral Regurgitation.

Functional mitral regurgitation (FMR) occurs as a result of global or segmental left ventricular (LV) dysfunction or left atrial dilatation, leading to mitral annular dilatation, papillary muscle displacement, mitral valve (MV) leaflet tethering, and leaflet remodeling. The prevalence of FMR continues to rise in the United States. Even mild FMR is associated with adverse clinical outcomes. Echocardiography is the primary imaging modality used to assess the type and severity of mitral regurgitation. FMR treatment depends on the etiology. Evidence-based pharmacologic and cardiac resynchronization therapies for underlying LV dysfunction remain the mainstay of treatment. Patients who remain symptomatic despite optimal medical therapy can be considered for surgical or percutaneous MV intervention. This article reviews the pathophysiology, imaging evaluation, and therapeutic options of FMR, highlighting the most recent developments in a rapidly evolving field.