Mitral valve anatomy
From Echocardiography in ICU
The mitral valve is located between the left atrium and the left ventricle. The mitral apparatus is composed from:
-anterior and posterior leaflets
The integrity of the whole mitral apparatus is important, mitral valve dysfunction will occur if any component is impaired.
The anterior leaflet is the closest from the aorta. The posterior leaflet is in continuity with the postero-lateral LV wall. The anterior and posterior leaflets are connecting at the antero-lateral and the postero-medial commissures.
Each leaflet is separated in 3 scallops, named 1 (lateral), 2 (middle) and 3 (medial).
Chordae and papillary muscles:
There are 2 papillary muscles:
-the anterolateral papillary muscle originates from the anterolateral LV wall and provides chordae to the antero-lateral half of anterior and posterior mitral leaflets-the posteromedial papillary muscle originates from the posterior LV wall and provides chordae to the postero-medial half of both leaflets.
The papillary muscles originate from the posterior and the lateral wall. Their function depends directly upon the integrity of the LV walls. LV remodeling, secondary to ischemic or non-ischemic cardiomyopathy, leads to papillary muscle dysfunction and mitral regurgitation.