• Isolated Mitral Regurgitation: Quantitative Assessment with 64-Section Multidetector CT Comparison with MR Imaging and Echocardiography

    Ying-Kun Guo, MD Zhi-Gang Yang, MD, PhD Gang Ning, MD Li Rao, MD Li Dong, MD Ying Pen, MD Tai-Ming Zhang, MD Yang Wu, MD Xiao-Chun Zhang, MD Qi-Ling Wang, MD

    Purpose: To evaluate the accuracy of 64-section multidetector com­puted tomography (CT) for the assessment of the severity of isolated mitral regurgitation by measuring ventricular volumetrics compared with those at magnetic resonance (Ml?) imaging and echocardiography.


    Materials and Methods: This study was approved by an institutional review board; patient informed consent was obtained. Forty-nine pa­tients (22 men, 27 women; mean age, 39 years ± 11 [standard deviation]) with isolated mitral regurgitation underwent retrospective electrocardiographically (ECG) gated 64-section CT, echocardiography, and MR imaging for the assessment of the seventy of mitral regurgitation. Stroke volumes of the left and right ventricles were mea­sured at 64-section CT and MR imaging. With these mea­surements, regurgitant volumes (RVs) and regurgitant fractions (RFs) were calculated and compared. The agree merit between CT and MR imaging was tested by using linear- regression and Bland-Altaian analyses. RFs were compared with corresponding echocardiographic grades (grades 1-IV) based on the absolute area of the regurgita­tion jet and in relation to the size of the left atrium by using Spearman rank order correlation and a weighted k test.

    Results: No significant differences were found in calculated RV and RF between 64-section CT and MR imaging (P = .56 and .87, respectively; paired t test). Regression analysis showed that 64-section CT correlated well with MR imag­ing for the measurement of RV (r = 0.89; 95% confidence interval [CI]: 0.81, 0.94) and for calculating the RF (r = 0.91; 95% CI: 0.84, 0.95). Bland-Altman analysis showed no significant differences in RV (bias, —1.0 ml.) and RF (bias, 0.2%) between 64-section CT and MR imaging. The severity of regurgitation estimated by using echocardiogra­phy con-elated well with that estimated by using 64-section CT (r = 0.95; 95% CI: 0.92, 0.97) and MR imaging (r = 0.94: 95% CI: 0.91, 0.96).


    Conclusion: ECG-gated 64-section CT helps provide quantitative infor­mation with high accuracy for determining the severity of isolated mitral regurgitation.