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Hemodialysis access stenosis: early detection with color Doppler US.

PURPOSE
To evaluate color Doppler ultrasound (US) in detection of subclinical stenosis of hemodialysis access grafts and fistulas.


MATERIALS AND METHODS
Doppler US was performed in 40 consecutive patients with no clinical or laboratory findings of hemodialysis access dysfunction. To assess the presence and percentage of stenosis, the maximum systolic blood velocity and velocity ratios were measured and the US images were assessed visually. Fistulography was recommended in patients who demonstrated stenosis greater than 50% at US.


RESULTS
At US, 32 of the 40 patients had evidence of stenosis greater than 50%. In 23 of the 32 patients, a follow-up fistulogram was obtained. Hemodynamically significant stenosis was confirmed in 19 of the 23 patients at fistulography. Percutaneous transluminal angioplasty was then performed in 18 of the 19 patients and was successful.


CONCLUSION
Color Doppler US is more sensitive than clinical or laboratory methods for detection of hemodialysis access stenosis. Screening with US appears to enable earlier detection and therapy.