D. Kececioglu et al., CORRELATION OF DOPPLER-DERIVED GRADIENTS WITH CARDIAC-CATHETERIZATIONGRADIENTS IN SUPRAVALVULAR AORTIC-STENOSIS, Herz, Kreislauf, 26(6), 1994, pp. 188-193
The purpose of this study was to compare estimates for pressure gradie
nts of supravalvular aortic stenosis derived from continuous wave Dopp
ler ultrasound with gradients measured directly by catheterization. Pr
essure gradients at rest (14 patients) and after exercise (nine patien
ts) were measured by fluid-filled catheters placed proximally and dist
ally to the stenosis. Doppler spectral signals were simultaneously obt
ained using a 2.0 MHz nonimaging transducer in the suprasternal notch.
Doppler and pressure recordings were analyzed to measure maximal inst
antaneous, mean, midsystolic and peak-to-peak gradients. Maximal insta
ntaneous Doppler gradient showed an excellent linear correlation with
maximal instantaneous catheterization gradient (r = 0.97; SEE = 10.4 m
mHg). The correlation of Doppler-estimated maximal gradient to peak-to
-peak catheterization gradient was also linear (r = 0.93; SEE = 16 mmH
g) but resulted in a systematic overestimation of the invasive peak-to
-peak gradient (mean overestimation: 22 mmHg; SEM = 4.8 mmHg). Measure
ment of the Doppler gradient at midsystole resulted in a better correl
ation with the peak-to-peak catheterization gradient (r = 0.96, SEE =
10.6 mmHg) and a minor overestimation (mean overestimation: 10.7 mmHg;
SEM = 3.1 mmHg). A good correlation was also seen between Doppler- an
d catheterization-derived mean gradients (r = 0.96; SEE = 6.2 mmHg). A
n excellent correlation was found between maximal instantaneous resp.
mean Doppler- and maximal instantaneous resp. mean catheterization-der
ived gradients after exercise (r = 0.96; SEE = 10.8 mmHg resp. r = 0.9
5, SEE = 6.5 mmHg). The results in this study suggest that pressure gr
adients obtained from continuous wave Doppler ultrasound are accurate
in predicting corresponding cardiac catheterization measurements.