Role of 3D echocardiography derived color-coded parametric models of the mitral valve in differential diagnosis of prolapse and billowing

Differentiation between mitral valve (MV) prolapse (MVP) and billowing (MVB) on 2D echocardiography (2DE) is challenging. We hypothesized that color-coded models of maximal leaflet displacement from the annular plane into the atrium derived from 3D transesophageal echocardiography (3DTEE) would allow discrimination between these lesions. 3DTEE imaging of the MV was performed in 52 patients with (N=40) and without (N= 12) degenerative MV disease. Definitive diagnosis of MVP versus MVB was made using inspection of dynamic 3D renderings and multiple 2D cut-planes extracted from 3D datasets. This was used as a reference standard to test an alternative approach, wherein the color-coded parametric models (MVQ, Philips) were inspected for integrity of the coaptation line and location of the maximally displaced portion of the leaflet. Diagnostic interpretations of these models by two independent readers were compared to the reference standard. In all cases of MVP, the color-coded models depicted loss of integrity of the coaptation line and maximal leaflet displacement extending to the coaptation line. MVB was depicted by preserved leaflet apposition with maximal displacement away from the coaptation line. Interpretation of the 52 color-coded models by 2 novice readers took 4-8 minutes and resulted in good agreement with the reference technique (kappa 0.82 and 0.74). 3D color-coded models provide a static display of MV leaflet displacement allowing diferentiation between MVP and MVB, without the need to inspect multiple planes. This provides information on lesion location and extent, which should be useful for planning MV repair.