Superior Leaflet of Right Atrioventricular Valve
Cuspis superior valvae atrioventricularis dextrae
Read moreMorphology/Structure
The superior leaflet is one of the three leaflets of the right atrioventricular valve. The leaflets are named according to the regions of the orifice that they attach to and are called the superior, inferior, and septal leaflets. The leaflets have a fibrous core and are coated with endocardium. Each leaflet has a rough, clear, and basal zone. The rough zone corresponds to the region of the free margin where it provides an attachment for the chordae tendineae. It's this region that comes into contact with the free margins of the adjacent leaflets when the valve is closed. The clear zone is smooth and more opaque and is the site of attachment of occasional chordae tendineae. The basal zone is thicker, due to increased collagen. It's the region where the leaflets insert into the anulus.
Key Features/Anatomical Relations
The leaflets of the right atrioventricular valve are supported by and attached to chordae tendineae, which in turn attaches to the papillary muscles of the ventricular wall. The superior leaflet is the largest component of the right atrioventricular valve. It attaches chiefly to the atrioventricular junction on the posterolateral aspect of the supraventricular crest and extends along its septal limb to the membranous part of the interventricular septum, ending at the anteroseptal commissure.
The superior leaflet is connected to the anterior and the inferior papillary muscles at the anteroinferior commissure via chordae tendineae.
Function
The superior leaflet of the right atrioventricular valve works with the inferior and septal leaflets to prevent retrograde blood flow into the left atrium during ventricular systole. It helps in the coordination of valve closure and ventricular contraction as it's connected to the right branch of the atrioventricular bundle via the moderator band.
