A Comparison of Flow Convergence With Other Transthoracic Echocardiographic Indexes of Prosthetic Mitral Regurgitation Gerald 1. Cohen, MD, Malcolm B. Davison, MB, BS, Allan L. Klein, MD, Ernesto E. Salcedo, MD, and William J. Stewart, MD, Cleveland) Ohio) and Brisbane) Australia Prosthetic shadowing of the left atrium may prevent detection of mitral regurgitation during transthoracic echocardiography. In 60 patients with mitral valves, Carpentier-Edwards (n = 20), St. Jude (n = 22), and cage-ball (n = 18), we blindly evaluated the accuracy of three transthoracic Doppler signs of significant (>2 +) mitral regurgitation: (I) color Doppler flow convergence, (2) a color Doppler jet of significant regurgitation in the left atrium, and (3) an intense continuous wave Doppler signal. All 60 patients had transesophageal echocardiography, 26 had cardiac catheterization, and 28 had surgery. The sensitivity and specificity of flow convergence for significant regurgitation by transesophageal echocardiography was 73% and 70%, respectively, compared with 33% and 93% for left atrial color Doppler, and 15% and 97% for continuous wave Doppler. The sensitivity of flow convergence in Carpentier-Edwards, St. Jude, and cage-ball valves was 80%, 73%, and 67%, respectively; whereas the sensitivity of left atrial color Doppler was 70%, 27%, and 0%, and the sensitivity of continuous wave Doppler was 33%, 0%, and 13%. Flow convergence was the only sign of significant regurgitation in 12 of 30 patients (40%); 10 of these patients had mechanical valves. We conclude flow convergence is a more sensitive, though less specific, predictor of significant mitral regurgitation than color Doppler, spatial mapping of the left atrium, and continuous wave Doppler, especially when a mechanical valve is present. (J AM Soc ECHOCARDIOGR 1992;5: 620-7.) Transthoracic echocardiographic assessment of mi- tral regurgitation is impeded when synthetic com- ponents of a prosthetic valve shield the left atrium from ultrasound imaging.l,2 However, pulsed wave Doppler can still detect the acceleration of blood towards the incompetent valve in the left ventricle. 3 The color Doppler equivalent of this phenomena or flow convergence has been found to be a useful sign of mitral regurgitation during transthoracic echocar- diography.4.7 The degree of prosthetic shadowing of the left atrium may vary according to valve type and profile. Although the intensity of the continuous wave and color Doppler signal may be reduced by this shad- owing,2,3 the effect of prosthetic valve type on flow convergence is not known. Therefore, the purpose of this study was (1) to assess the accuracy of flow convergence during transthoracic echocardiography as a predictor of significant mitral regurgitation in patients with different prosthetic valve types, and (2) to compare transthoracic flow convergence, color Doppler spatial mapping of the left atrium, and con- tinuous wave Doppler as signs of significant pros- thetic mitral regurgitation. From the Department of Cardiology of The Cleveland Clinic Foundation, and St. Andrews War Memorial Hospital and the Mater Misericordiae Hospital, Brisbane, Australia. This data was presented at the 40th Scientific Session of the Amer- ican College of Cardiology, Atlanta, Georgia, March 1991. Reprint requests: Gerald I. Cohen, MD, The Cleveland Clinic Foundation, Dept. of Cardiology F-15, 9500 Euclid Ave., Cleve- land, OH 44106. 27/1/40744 620