Normal Ultrasound Doppler Parameters for Functioning AV Fistulas

Doppler ultrasound (DUS) is a highly sensitive and specific test for assessment of the morphology of stenoses and measure blood flow within arteriovenous fistulas (AVFs). Retrospective review of 150 Doppler studies (121 patients) performed by a single radiologist were analyzed in conjunction with contemporaneous clinical dialysis function. Volume flow in the brachial artery, peak systolic velocity (PSV), and size of the anastomosis (diameter and intimal thickness) were recorded. Volume flow in the brachial artery of ≈>1000 mL/min is a predictor of good fistula function. Volume flow in the brachial artery negatively correlates with both the reduction in perianastomotic diameter and increased intimal thickness (P = .02) and positively correlates with increased diameter of the perianastomotic vein (PAV) (P < .0001). Measurements of PSV across the PAV do not correlate with fistula dysfunction or a significant stenosis. Volume flow of >1000 mL/min in the brachial artery and a PAV diameter of ≥3.5 mm are predictive of a well-functioning fistula. Intimal thickening at the anastomosis can be measured on ultrasound and may be another useful parameter in the assessment of a failing fistula. These parameters could be used to exclude a significant inflow stenosis