• CARDIAC PROCEDURES AND THERAPY

Indentations in the posterior leaflet of the mitral valve are part of the normal anatomy and are the landmarks that surgeons use to distinguish the typical three scallops: P1, P2 and P3. While the typical finding of three scallops occurs in about 90% of patients, there may be more subtle indentations and some have referred to four or more scallops.1 These are just expected biological variation in the complex structure of the mitral valve. Carpentier has noted that these posterior leaflet indentations ‘are normal anatomical structures that allow the leaflet to fully open during diastole’.2 The chords that supply the indentations are typically normal length and have been referred to as ‘cleft chordae’ at least since the 1960s.1 They rarely prolapse or rupture like the ‘marginal’ (primary) chords that supply the free edge of the tip of the scallops.2 The height of the three posterior leaflet scallops varies (table 1) and normally P2 is the tallest and P1 the shortest. In patients with degenerative mitral regurgitation (DMR) (Carpentier type II prolapse), these segments are elongated (table 1), but these lengths are quite variable.3 P2 averaged 19 mm in a recent study and the adjacent P1 scallop was elongated, but still significantly shorter (11 mm).3

Mantovani and colleagues provide rigorous structured analysis of 2D and 3D echocardiographic imaging in 49 patients planned for mitral valve repair. The definition of a …