Failing Arteriovenous Hemodialysis Fistulas: Assessment with Magnetic Resonance Angiography

RATIONALE AND OBJECTIVES. The authors sought to evaluate prospectively magnetic resonance angiography (MRA) versus fistulography in the detection and characterization of complications associated with malfunctioning hemodialysis access fistulas (arteriovenous fistulas [AVF]). METHODS. Nineteen patients with clinical AVF dysfunction were studied by MRA and fistulography. Data from each study were collected prospectively and analyzed in a blinded manner. RESULTS. The main diagnosis was stenosis in eight patients, thrombosis in five patients (mural thrombosis with preserved flow in one), aneurysm without stenosis in two patients, and normal AVF in four patients. A hazy flow void, assumed to be related to turbulence, was observed in normal arterial anastomoses. When flow void was considered as a criterion of stenosis or thrombosis, one false-positive and one false-negative MRA study were determined, yielding a sensitivity and specificity of 92% and 86%, respectively. CONCLUSIONS. Magnetic resonance angiography is a feasible and sensitive technique with which to portray suspected malfunctioning hemodialysis access fistulas.