Stenosis of the main artery supplying an organ: effect of end-organ vascular resistance on the poststenotic peak systolic velocity in an in vitro hydraulic model at Doppler US.
OBJECTIVE
To test the hypothesis that increased end-organ vascular resistance reduces blood flow to the kidney, thus reducing the mean velocity in the renal artery and secondarily lowering the peak systolic velocity (PSV).


METHODS
An in vitro hydraulic model with a pulsatile pump, blood-mimicking fluid, interchangeable stenoses, and variable compliance and resistance was used to investigate the relationship between end-organ vascular resistance and poststenotic PSV.


RESULTS
Poststenotic PSV was mildly dependent on end-organ vascular resistance and decreased with increasing resistance.


CONCLUSIONS
The results help explain some of the reported variability from using poststenotic PSV to detect hemodynamically significant renal arterial stenoses, but the effect is not great enough to completely explain the variability. Other factors not investigated in this study must be at work as well.
Department of Radiology, University of Michigan Medical Center, Ann Arbor 48109-0326, USA. ronbude@umich.edu
R O
RO
Bude
R G
RG
Larson
W W
WW
Nichols
J M
JM
Rubin
D001783:Blood Flow Velocity / Q000502:physiology*; D006801:Humans; D007668:Kidney / Q000098:blood supply*; D008955:Models, Cardiovascular; D011673:Pulsatile Flow / Q000502:physiology; D012016:Reference Values; D012077:Renal Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D012078:Renal Artery Obstruction / Q000000981:diagnostic imaging* / Q000503:physiopathology; D013599:Systole / Q000502:physiology*; D018608:Ultrasonography, Doppler; D014655:Vascular Resistance / Q000502:physiology*