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Role of color doppler ultrasound for assessment of arteriovenous fistula dysfunction in hemodialysis patients

Background and objective Arteriovenous fistulas (AVFs) are the vascular access of choice for hemodialysis with a lower incidence of complications and longer survival than prosthetic grafts or central venous catheters. Our aim was to evaluate the role of color Doppler ultrasound (CDUS) in the detection and characterization of complications of AVF dialysis access. Materials and methods During a 9-month duration, we prospectively evaluated 25 patients with clinically suspected AVF complications using CDUS examination of the upper limbs. There were 11 (44%) males and 14 (56%) females, ranging in age from 8 to 70 years. All patients were examined after reconstruction of AVF for the assessment of vascular access complications. Doppler indices were measured in the afferent arteries, at the site of anastomosis, and the draining veins. Results All 25 patients had shunt complications. Venous thrombosis was the highest among all complication (n=12, 48%), followed by stenosis (n=11, 44%), aneurysm and pseudoaneurysmal formation (n=5, 20%), and infection (n=1, 4%). Four patients had more than one complication. Sixteen (64%) patients had complicated fistulas requiring further intervention, either surgical management [reconstruction of new fistula (n=3), ligation (n=1), graft (n=1), and superficialization (n=2)] or radiological intervention [percutaneous transluminal angioplasty (n=5), thrombectomy (n=2), and percutaneous transluminal angioplasty and thrombectomy (n=2)]. Conclusion CDUS is a noninvasive diagnostic tool for early detection and localization of complications of AVFs that allows detection of possible causes of vascular access malfunction.