Subaortic flow profiles in aortic valve disease: a two-dimensional color Doppler study

With time-corrected color Doppler echocardiography, the aortic subvalvular spatial flow velocity profile was registered in two perpendicular planes in 10 patients with aortic valve disease and in 5 healthy control subjects. Patients with predominant aortic valve stenosis had a fairly flat profile, and the subvalvular diameter, obtained from left parasternal two-dimensional tissue imaging, provided a good estimate of the mean of the two transverse flow axes. This explains the accuracy in determination of stroke volume and aortic valve area that is reported in studies on patients with aortic valve stenosis when the continuity equation is used. However, the use of apical pulsed Doppler ultrasound registrations from the left ventricular outflow tract and parasternal two-dimensional echocardiography for flow area calculation may introduce large errors in calculated stroke volume in certain patients with aortic regurgitation and in normal subjects, because of a non-flat spatial velocity profile or an inaccurate estimate of flow area.