Association of Mitral Annular Area With Effective Regurgitant Orifice Area Independent of Jet Momentum: A Three-Dimensional Echocardiography Cohort Analysis.

BACKGROUND

Mitral regurgitation (MR) severity is traditionally assessed using hemodynamic parameters, but the contribution of structural remodeling, specifically mitral annular area (MAA), remains incompletely understood. We hypothesized that MAA is independently associated with effective regurgitant orifice area (EROA) after accounting for jet momentum.

METHODS

This prospective study enrolled 120 patients with chronic MR (60 degenerative, 60 functional) who underwent comprehensive two-dimensional echocardiography (2DE) and three-dimensional transesophageal echocardiography (3D TEE). MAA was measured using 3D TEE, and EROA was quantified using 3D vena contracta area. The independent association between MAA and EROA was assessed using multivariable linear regression.

RESULTS

Mean MAA was larger in functional MR compared to degenerative MR (14.2 ± 3.1 cm2 versus 10.6 ± 2.2 cm2, p < 0.001). The elliptical model combining apical long-axis and apical two-chamber views demonstrated the best agreement with the reference standard (correlation coefficient 0.98). MAA showed significant correlation with EROA (r = 0.71, p < 0.001). In multivariable analysis adjusted for jet momentum, left ventricular volumes, and MR etiology, MAA remained independently associated with EROA (standardized β = 0.38, 95% confidence interval 0.15-0.61, p = 0.002). MAA exhibited good diagnostic performance for severe MR (area under the curve 0.83), with incremental value when combined with jet momentum (area under the curve 0.91, p = 0.008).

CONCLUSIONS

MAA is independently associated with EROA in patients with chronic (MR), supporting the hypothesis that annular remodeling is associated with regurgitant severity as a structural parameter complementary to hemodynamic indices.