Estimation of the spatial mean and peak flow velocities using real-time 3D color Doppler echocardiography: in vitro and in vivo studies

Using real-time, three-dimensional (3D) color Doppler, experimental studies were performed to quantify velocity in the out flow tract from cross-sectional, short axis images. In vitro experiments showed an excellent linear correlation between the reference pulsed wave (PW) Doppler and 3D color estimates of the peak velocities (r=0.98). In an animal experiment 3D peak flow velocities showed a reasonably good agreement with reference peak velocities by PW Doppler (r=0.76, delta =+11.6%). The spatial mean velocity by 3D showed a good linear relationship with PW peak velocity, but with an anticipated underestimation (r=0.81, delta=-43 %) due to the non-uniform velocity profile. Real-time, color 3D echocardiography was capable of quantifying velocities accurately, permitting the calculation of flow volume without any geometrical assumptions about flow distribution.