Hypertrophic cardiomyopathy: Mechanisms of mitral regurgitation


Aurora Sinai/Aurora St. Luke’s Medical Centers


Purpose of review

The objectives of this review are to highlight the pathophysiology and treatment strategies of mitral valve regurgitation (MR) in patients with hypertrophic cardiomyopathy (HCM).

Recent findings

There is increasing recognition that MR in HCM is related to a complex interaction of abnormalities in the mitral valve and subvalvular apparatus that predispose to development of left ventricular outflow tract (LVOT) obstruction. When lifestyle and pharmacologic treatments do not suffice, surgical myectomy remains the primary therapy for relieving symptomatic obstructive HCM and associated MR. Alcohol septal ablation has also been associated with a reduction in LVOT gradient and MR severity. For patients with MR and intrinsic mitral valve abnormalities, thinner septal walls, or residual MR after septal reduction, concomitant mitral valve repair can be considered. Transcatheter edge-to-edge repair has emerged as an additional option in select cases.


A variety of anatomic and pathophysiologic mechanisms contributes to the development of MR in patients with HCM. Although septal reduction therapies are mostly successful in decreasing the severity of MR, a detailed assessment of mitral valve anatomy and structure is critical in determining which patients might benefit from concomitant surgical or transcatheter mitral valve interventions.