Evaluation of eccentric aortic regurgitation by color Doppler jet and color Doppler-imaged vena contracta measurements: An animal study of quantified aortic regurgitation

To evaluate the utility of measurements of the color Doppler jet area, jet length, and width of the color Doppler-imaged vena contracts (the smallest flow diameter in any part of the flow acceleration field) as methods for quantifying aortic regurgitation (AR), eight sheep with surgically induced AR were studied. AR was quantified as peak and mean regurgitant flow rates, regurgitant stroke volumes, and regurgitant fractions as determined with pulmonary end aortic electromagnetic flow probes and flowmeters balanced against each other. Simple linear regression analysis between the maximal color jet areas, jet length, and flowmeter data showed only moderately good correlation (jet area: 0.42 ≤ r ≤ 0.57, SEE = 2.85 cm²; jet length: 0.42 ≤ r ≤ 0.59, SEE = 1.23 cm). In contrast, the width of color Doppler-imaged vena contracts was a better indicator of the severity of AR on the basis of the electromagnetic flowmeter methods (0.73 ≤ r ≤ 0.90, SEE = 0.15 cm). Therefore the color Doppler jet length and jet area methods have limited use for determining AR, whereas the width of the color Doppler-imaged vena contracta can be used for quantifying the severity of AR.