Schematic and 3D echocardiographic image of mitral valve leaflets

Anatomically, the mitral valve is formed by a long and narrow anterior leaflet and a shorter posterior leaflet occupying a larger portion of the annular circumference.

(A) Anatomical description proposed by Carpentier, with the posterior leaflet divided into anterolateral (P1), middle (P2), and postero-medial (P3) scallops. While the anterior leaflet does not have obvious anatomical divisions, corresponding segments are labeled similarly A1 to A3.