[Clinical value of Doppler sonography in the quantification of aortic stenoses]

Results of CW-Doppler measurements in 34 patients with aortic stenosis have been compared with catheter-derived data. The relevance of this noninvasive method for clinical decision making was examined. There was a good correlation between Doppler peak gradients and corresponding catheter values (r = 0.96). This gradient, however, was of limited clinical significance because, especially with simultaneous aortic insufficiency, it was not possible to characterize the severity of the stenosis over a wide range. The correlation for the mean gradient of both methods was also excellent (r = 0.94). Hence it was possible to derive, in a noninvasive way, a clinically proven parameter of the severity of aortic stenosis. 90% of Doppler mean gradients were found within +/- 15 mm Hg of the corresponding catheter data. The ratio of modified time to peak to modified ejection time was calculated to characterize spectral shapes. This value was also well correlated with the mean gradient (r = 0.91). A ratio of 0.3 separated patients with mean gradients above or below 50 mm Hg. The simultaneous consideration of Doppler derived mean gradient and spectral shape proved to be a valuable method for quantifying aortic stenosis for clinical purposes.