To establish the accuracy of Doppler echocardiography in the assessment of chronic aortic regurgitation (AR), 87 patients were included in a two-step prospective study. In a first consecutive series of 56 patients, two-dimensional directed M-mode echocardiography and pulsed wave Doppler (PWD) studies were performed within a 24-hour interval of a conventional contrast aortic angiography, which showed AR in 46 patients. Sensitivity and specificity of PWD in the detection of AR were both 100%. To quantitate AR, a left ventricular outflow tract (LVOT) PWD mapping was scored. Significant differences between 1, 2, and 3 to 4 angiographic grades of AR were obtained. As some overlap existed between groups, a multifactorial analysis of PWD and echocardiographic measurements was performed: optimal discrimination was obtained when a new score combining LVOT mapping by PWD, diastolic left ventricular diameter, and aortic root dimension was considered. A prospective validation of this combined echocardiographic-Doppler method was then applied on a second group of 31 catheterized patients with AR. Correlation obtained (r = 0.86; p less than 0.001) confirmed the accuracy of this new method in the prediction of the severity of AR.