Quantitation of aortic regurgitation by Doppler echocardiography: A practical approach

Aortic regurgitation is most frequently assessed noninvasively by Doppler echocardiography by use of continuous wave and Doppler color flow mapping. To compare both Doppler methods, 161 patients who had undergone cardiac catheterization and complete echocardiographic studies were studied. The continuous wave parameters analyzed included the slope of the diastolic deceleration and the pressure half-time of the regurgitant jet. From color flow Doppler, conventional parameters such as JH and its ratio to LVOH, JASA and its ratio to LVOA, and the regurgitant JA and its ratio to the LVA were obtained. The JH/LVOH was the color flow parameter that best correlated with angiography (r = 0.91). A ratio of ≤25% was used to predict mild aortic regurgitation with 96% accuracy. A ratio of ≥40% was also used to predict severe aortic regurgitation (3 to 4+) with 96 % accuracy. Absolute JH at the origin of the regurgitant jet was the second best color flow parameter that correlated with angiography (r = 0.89). When continuous wave—derived slope was used, a significant overlap among different degrees of aortic regurgitation was observed. Predictive accuracy for mild aortic regurgitation was 70% by using a slope <2 m/sec2 and 86% for severe aortic regurgitation when using a slope>3 m/sec2. In conclusion, color flow Doppler appears to be superior to continuous wave Doppler in the assessment of aortic regurgitation. The JH/LVOH appears to be the best color parameter for quantifying aortic regurgitation. The measurement of the absolute JH at its origin appears to be the simplest and most practical method for assessing the degree of aortic regurgitation.