Peak Mitral Inflow Velocity Predicts Mitral Regurgitation Severity

Objectives. Mitral regurgitation (MR) is common echocardiographic finding; however, there is no simple accurate method for quantification. The aim of this study was to develop an easily measured screening variable for hemodynamically significant MR. Background. The added regurgitant volume in MR increases the left atrial to left ventricular gradient, which then increases the peak mitral inflow or the peak E wave velocity. Our hypothesis was that peak E wave velocity and the E/ ratio increase in proportion to MR severity. Methods. We performed retrospective analysis of 102 consecutive patients with varying grades of MR seen in the Adult Echocardiography Laboratory at the University of California, San Francisco. Peak E wave velocity, peak wave velocity, E/ ratio and E wave deceleration time were measured in all patients. The reference standard for MR was qualitative echocardiographic evaluation by an expert and quantitation of regurgitant fraction using two-dimensional and Doppler echocardiography. Results. Peak E wave velocity was seen to increase in proportion to MR severity, with significant difference between the different groups (F = 37, p < 0.0001). Peak E wave velocity correlated with regurgitant fraction (r = 0.52, p < 0.001). Furthermore, an E wave velocity >1.2 m/s identified 24 of 27 patients with severe MR (sensitivity 86%, specificity 86%, positive predictive value 75%). An wave dominant pattern excluded the presence of severe MR. The E/ ratio also increased in proportion to MR severity. Peak wave velocity and E wave deceleration time showed no correlation with MR severity. Conclusions. Peak E wave velocity is easy to obtain and is therefore widely applicable in clinical practice as screening tool for evaluating MR severity.