Echocardiographic imaging of systolic anterior motion caused by extremely elongated posterior mitral leaflet in hypertrophic cardiomyopathy

Abstract

Systolic anterior motion is frequently observed in hypertrophic cardiomyopathy (HCM) and causes left ventricular outflowtract (LVOT) obstruction, and systolic anterior motion (SAM) isgenerally seen at the anterior mitral leaflet (AML) (1). However,an isolated SAM of the posterior mitral leaflet (PML) can be unusually seen. Full coaptation of mitral leaflets and an absenceof mitral regurgitation are distinct features of this pattern, andelongation of PML is also essential. We present a case with thisunusual pattern to increase awareness about this unique mechanism in HCM.