Journal of Ultrasound in Medicine, Vol 12, Issue 1 17-22, Copyright © 1993 by American Institute of Ultrasound in Medicine
Noninvasive assessment of pressure gradients across iliac artery stenoses: duplex and catheter correlative study
A. L. Strauss, F. J. Roth and H. Rieger
Department of Medicine, Hospital for Vascular Diseases, Engelskirchen, Germany.
The present study investigates prospectively the validity and accuracy of
the simplified Bernoulli equation in the duplex-derived determination of
pressure gradients across iliac artery stenoses in patients with occlusive
artery disease. In 28 patients (age range, 38 to 76 years; mean, 53 years)
with short iliac artery stenoses, we obtained both duplex scan stenotic jet
velocity and catheter pressure measurements. Mean and maximum pressure
gradients were determined by both methods, as was the peak-to-peak catheter
gradient. The correlation between the duplex-determined and
nonsimultaneously measured catheter mean pressure gradients was r = 0.77
(standard error of the estimate [SEE] = 5 mm Hg), that between the
duplex-derived and catheter-determined maximum pressure gradients was r =
0.80 (SEE = 10 mm Hg), and that between maximum duplex-determined and
peak-to-peak catheter gradient was r = 0.76 (SEE = 12 mm Hg). The
peak-to-peak catheter gradient was significantly lower than the maximum
duplex-derived gradient (46 versus 53 mm Hg, P < 0.05).
Duplex-determined mean pressure gradient decreased from 15 +/- 6 to 3 +/- 1
mm Hg after balloon angioplasty of the iliac stenoses. Duplex scan can be
used to predict pressure gradients across short iliac artery stenoses,
provided that errors caused by angle malcompensation are prevented.
