Valvular heart disease
Comparison of Accuracy of Mitral Valve Regurgitation Volume Determined by Three-Dimensional Transesophageal Echocardiography Versus Cardiac Magnetic Resonance Imaging

https://doi.org/10.1016/j.amjcard.2012.05.037Get rights and content

Direct planimetry of anatomic regurgitation orifice area (AROA) using 3-dimensional transesophageal echocardiography (TEE) has been described. This study sought to (1) compare mitral valve regurgitant volume (RV) derived by AROA using 3-dimensional TEE with RV obtained by cardiac magnetic resonance (CMR) imaging and (2) determine the impact of AROA and flow velocity changes throughout systole on the dynamic variation in mitral regurgitation. In 43 patients (71 ± 11 years old) with mild to severe mitral regurgitation, 3-dimensional TEE and CMR were performed. Mitral valve RV was determined based on (1) AROA at 5 subintervals of systole and analysis of the regurgitant continuous-wave Doppler signal at equal durations of systole, (2) effective regurgitation orifice area (EROA) using the proximal isovelocity surface area method, (3) CMR with subtraction of aortic outflow volume from left ventricular stroke volume. RV calculated by AROA tended to overestimate RV less than RV calculated by EROA compared to RV by CMR (average bias +20 ml, 95% confidence interval [CI] −41 to +81, vs +13 ml, 95% CI −22 to 47). In patients with RV >30 ml by CMR, overestimation of RV using the AROA method was less than using the EROA method (difference in means +18 ml, 95% CI 4 to 32, p <0.001). AROA determined by 3-dimensional TEE varied by only 18% among the 5 subintervals of systole, and the velocity time integral of the subinterval with the highest flow was 120% of the subinterval with the lowest flow. In conclusion, 3-dimensional TEE allows accurate analysis of mitral valve RV. In the clinically relevant group of patients with RV >30 ml as defined by CMR, the AROA method results in less overestimation of RV than the EROA method. Changes in AROA during systole contribute much less to dynamic variation in mitral regurgitation severity than changes in regurgitant flow velocity.

Section snippets

Methods

We enrolled 46 consecutive patients with 1 to 4+ mitral regurgitation defined by routine color Doppler echocardiography. Patients with significant mitral stenosis (mitral valve area <2.0 cm2), mitral prosthesis, irregular rhythm or aortic regurgitation grade >1 were not included. Because of impaired 2-dimensional transesophageal echocardiographic image quality, 3 patients were excluded. In the remaining 43 patients (95%) color Doppler TEE, real-time 3-dimensional TEE, and CMR were performed

Results

Clinical characteristics of the 46 patients with 1 to 4+ mitral regurgitation are presented in Table 1. Most mitral regurgitation was due to functional mitral regurgitation, although prolapse or flail leaflet of the mitral valve and rheumatic disease were other common causes. RVs determined by the 3 methods were as follows: RV by EROA 51.5 ± 36.3 ml, RV by AROA 44.7 ± 17.7 ml, and RV by CMR 32.0 ± 15.3 ml. Using only the largest AROA instead of the 5 subinterval AROAs for calculation of RV

Discussion

The major findings of this study are (1) 3-dimensional TEE allows accurate analysis of mitral valve RV; (2) in the clinically important group of patients with reference RV >30 ml, application of the AROA method results in less overestimation of RV compared to application of the EROA method; and (3) dynamic variation of mitral regurgitation is determined predominantly by changes in regurgitant flow velocity and less by changes in AROA.

Accurate noninvasive quantification of mitral regurgitation

References (21)

There are more references available in the full text version of this article.

Cited by (0)

†

Drs. Hamada and Altiok contributed equally to this article.

View full text
Copyright © 2012 Elsevier Inc. All rights reserved.