Figure 10.
Mitral valve enlargement in SAM. a | SAM relates to a combination of a susceptible mitral valve, which is anteriorly positioned and elongated, encountering a posteriorly shifted left ventricular outflow stream, diverted by hypertrophy of the upper IVS. Anterior PM displacement decreases the posterior restraining force on the leaflets. Leaflet elongation allows greater leaflet excursion to create obstructive SAM. b | SAM of elongated leaflets (arrows) approaching the IVS and obstructing left ventricular outflow. Abbreviations: AML, anterior mitral leaflet; Ao, aorta; IVS, interventricular septum; LA, left atrium; LV, left ventricle; PM, papillary muscle; PML, posterior mitral leaflet; SAM, systolic anterior motion.