Influence of jet impingement on color Doppler parameters of aortic regurgitation

In vitro studies have demonstrated that the characteristics of a color Doppler jet are influenced by a number of factors including jet eccentricity and jet impingement. To explore the relationship of a jet impingement and aortic regurgitant color Doppler jet parameters, jet area, width, and length were measured from apical echocardiographic views of 84 patients 4 +/- 11 days prior to catheterization and compared to angiographic grade. An impinging color jet contacted the interventricular septum or mitral valve beneath the aortic valve in the imaging plane and a nonimpinging jet did not contact the septum or mitral valve in the imaging plane. As expected, the percentage of patients with impinging jets increased with aortic regurgitation angiographic grade. Neither left ventricular chamber dimensions nor the presence of an aortic prosthesis significantly influenced the color Doppler variables. For a given angiographic grade of aortic regurgitation, impinging jets were associated with larger color Doppler jet widths (P less than 0.05) and areas (P = 0.001) than nonimpinging jets. The color Doppler area and length increased significantly with angiographic grade for nonimpinging jets (P less than 0.05) but not for impinging jets. Impinging jets are associated with larger color Doppler widths and areas than nonimpinging jets for a given grade of aortic regurgitation, possibly because of the effect of jet deflection toward an adjacent wall. Jet impinging should be considered when using color Doppler techniques to evaluate aortic regurgitation.