FIG 55.4 Schematic images of the mitral valve (A) Systolic frame in a normal patient showing a competent mitral valve in the closed position Note the extent of coaptation of the two leaflets (B) Diastolic frame showing a wide open mitral valve (C) Systolic frame in regurgitant heart disease The anterior mitral valve leaflet (AMVL) is shortened and thickened as a result of fibrosis The posterior mitral valve leaflet (PMVL) is relatively fixed The tip of the AMVL faces the left atrium The leaflets do not coapt (D) Diastolic frame showing restriction of the mitral valve orifice because of restricted mobility of both AMVL and PMVL Note the “dog leg” deformity of the AMVL FIG 55.5 Echocardiographic equivalents of Fig 55-4 Echocardiograms from a normal patient during systole (A) and diastole (B) (C–D) Echocardiograms obtained from a patient with rheumatic heart disease and mitral valve disease (C) Systolic frame demonstrating thickening of the anterior mitral valve leaflet (AMVL) tip and a fixed posterior mitral valve leaflet (PMVL) The tip of the AMVL does not coapt with the PMVL, resulting in a visible gap The mitral regurgitation occurs through this gap and is directed toward the posterior and lateral wall of the left atrium