Background-Planimetry of mitral valve area (MVA) is difficult in calcific mitral stenosis (CaMS) in which limiting orifice is near the annulus, and unlike rheumatic mitral stenosis (RhMS), does not present an area for planimetry at the leaflet tips. Moreover, pressure half time (PHT)-derived MVA (MVA PHT ) has limitations in patients with CaMS in whom there are coexisting conditions that affect LV chamber compliance. We tested the hypothesis that real-time 3-dimensional echocardiography (RT3D) can guide measurement at the narrowest orifice in CaMS.

We tested the hypothesis that vena contracta (VC) cross-sectional area in patients with mitral regurgitation (MR) can be reproducibly measured by real-time three-dimensional echocardiography (RT3DE) and correlates well with volumetric effective regurgitant orifice area (EROA). Earlier MR repair requires accurate noninvasive measures, but VC area is practically difficult to image in 2D views, which are often oblique to it. 3DE can provide an otherwise unobtainable true cross-sectional view. In 45 patients with >mild MR, 44% eccentric, 2D and 3D VC areas were measured and correlated with EROA derived from regurgitant stroke volume. RT3DE VC area correlated and agreed well with EROA for both central and eccentric jets (r 2 =0.86, SEE=0.02 cm 2 , difference = 0.04±0.06 cm 2 , p=NS). For eccentric jets, 2DE overestimated VC width compared with 3DE (p=0.024) and correlated more poorly with EROA (r 2 =0.61 vs. 0.85, p<0.001), causing clinical misclassification in 45% of patients with eccentric MR. Interobserver variability for 3D VC area was 0.03 cm 2 (7.5% of the mean, r=0.95); intraobserver was 0.01 cm 2 (2.5%, r=0.97). In conclusion, RT3DE accurately and reproducibly quantifies vena contracta cross-sectional area in patients with both central and eccentric MR. Rapid acquisition and intuitive analysis promote practical clinical application of this central, directly visualized measure and its correlation with outcome.

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