Assessment of Aortic Regurgitation by Real-time Two-dimensional Doppler Flow Mapping System

ABSTRACT

In the real-time two-dimensional Doppler flow mapping(2DD) system, Doppler signals are processed using auto-correlation technique, so that the direction, velocity and turbulence of the intracardiac blood flow are displayed by coloration on the B mode image of the heart in real time. Aortic regurgitant flow is imaged as a mosaic jet spurting out from the aortic valve orifice to cardiac chamber. Dynamic features in the direction and extent of regurgitant flow and the site of regurgitation on the aortic valve orifice are readily obtained. Feasibility of the 2DD system in the assesment of aortic regurgitation was examined in 30 cases documented by angiography. In 30 cases, there were 20 cases with aortic regurgitation(AR) aged 16 to 57 years(mean 34) and 10 cases without AR aged 17 to 39 years(mean 30). The underlying disorders of AR were rheumatic in 15 cases, bicuspid aortic valve in 1, ventricular septal defect in 1, aortitis in 1, Marfan's syndrome in 1 and unknown in 1. The results are as follows : 1) In 19 out of 20 cases with AR the 2DD showed regurgitant jet spurting out from valve orifice(sensitivity=95%). One case missed by the 2DD had 1+AR. None of the 10 cases who had no AR manifested the evidence of AR on the 2DD(specificity=100%). 2) There was an excellent positive correlation between the maximal jet length of regurgitant flow on the 2DD and angiographic severity of regurgitation(r=0.998, p or = 3+) AR. 5) In all 8 cases with fluttering of anterior mitral leaflet and 8 out of 9 cases with fluttering of interventricular septum, a regurgitant jet impinged on them. The results of this investigation indicate that the 2DD system is a very useful and unique noninvasive technique in the detection, estimation of severity and spatial orientation of AR.