1020-2 Evaluation of Aortic Regurgitation (AR) Using Color Doppler Jet Measurement: An Animal Study with Quantified AR

Although the color Doppler (CD) jet width and area measurement methods have been widely used clinically for evaluating the severity of aortic regurgitation (AR), there have been no studies comparing CD jet measurements with a strictly quantifiable reference standard for determining regurgitant volume. The purpose of the present study was to evaluate the accuracy of the CD jet area planimetry. jet length and jet neck width measurement methods for quantifying chronic AR. In 6 sheep, 3 with partial resection of the right coronary cusp and 3 with partial resection of the non coronary cusp to produce chronic AR, 21 hemodynamically different states were obtained pharmacologically 20 weeks 20 weeks recovery. AR jet length and area and the width of the imaged flow connection between the flow acceleration field and the expanding regurgitant jet, which we call the jet neck at its smallest diameter were imaged and measured using a Vingmed 775 scanner. The peak and mean regurgitant flow rates (RFR), regurgitant stroke volumes (RSV) and regurgitant fractions (RF) were determined using pulmonary and aortic electromagnetic flow probes and meters balanced against each other. Results using simple liner regression analysis between the CD jet data and hemodynamic data were as follows.Peak RFRMean RFRRSVRFAR jet arear=0.66r=0.74r=0.67r=0.68AR jet lengthr=0.40r=0.51r=0.46r=0.46jet neck widthr=0.88r=0.95r=0.97r=0.89jet neck/LVOTr=0.84r=0.91r=0.94r=0.89LVOT: Left Ventricular Outflow TractOur study shows that the CD jet area and length methods have limited use for determining AR severity, and that the jet neck width method, either with or without normalization for LVOT size depending on patient population studied, should be most accurate for evaluating severity of AR