Quantitation of aortic regurgitation by colour coded cross-sectional Doppler echocardiography

In 60 patients with aortic regurgitation, angiography and cross-sectional Doppler echocardiography have been compared in order to examine the reliability of the noninvasive method in quantitating aortic regurgitation. In a parasternal short-axis view just below the aortic valve, the ratio of the cross-sectional area of the jet divided by the cross-sectional area of the left ventricular outflow tract was determined. This measurement was possible in 50 patients (83%). Grossman's classification was used as the criterion for assessing the severity of aortic regurgitation by angiography. Values for the ratio of grade I ranged from 0.03 to 0.18, II 0.06 to 0.29, III 0.30 to 0.55, and IV 0.40 to 0.65. Assuming four Doppler grades (less than 0.15, 0.15-0.29, 0.30-0.44, greater than or equal to 0.45), we found complete agreement between the two methods in 42 patients (84%). In six cases there was underestimation, in two cases overestimation, by one grade only. Considering all cases, X2 analysis gave 96.6, P less than 0.00001, the contingency coefficient was 0.81. We conclude that, using this measurement, cross-sectional Doppler is a reliable method for the quantitative evaluation of aortic regurgitation.