Carpentier nomenclature of mitral leaflet scallops
Carpentier nomenclature of mitral leaflet scallops is important in assessing the mitral leaflets while planning echo. The scallops can be identified well by transesophageal echocardiography, preferably in three dimensional mode. Two indentations in the posterior leaflet divides it into three independently mobile scallops named P1, P2 and P3. Anterior leaflet is non indented, by but has been divided into three corresponding virtual subdivisions known as A1, A2 and A3.
Posterior leaflets have a quadrangular shape while the anterior leaflets have semicircular shape. These can be visualized well by a magnified three dimensional echocardiographic (3DE) image. Systolic billowing of the mitral leaflets into the left atrium is rather uniform with an exception in the P1 and P2 region. P1 has a single focus of regional heterogeneity in the curvature while P2 has two large foci of heterogeneity in curvature. This may be the reason why these two segments (P1 and P2) have a higher propensity for prolapse and becoming flail.
Prof. Alain Carpentier was one of the pioneers in mitral valve repair, who introduced the nomenclature of mitral scallops [1,2].