IMAGING OF DIALYSIS ACCESS - A REVIEW OF 67 FAILING FISTULAS INVESTIGATED BY INTRAVENOUS DIGITAL SUBTRACTION ANGIOGRAPHY

We have reviewed 67 failing haemodialysis fistulas imaged by intravenous digital subtraction angiography (IVDSA). Peripheral venous injection of non-ionic contrast was used in all examinations. No complications relating to peripheral injection, contrast dose or fluid load were experienced. Image quality was poor, owing to inadequate vascular opacification, in 1/67. Image quality was excellent (53/67), or good (13/67) in the remaining 66. 56/66 of these examinations were diagnostic. Diagnoses included abnormalities of feeding arteries, anastomoses, draining veins, and central veins. Multiple abnormalities were demonstrated in 10/56 examinations. Conventional arm venography was performed in addition to IVDSA in five cases where venous images were inadequate owing to anastomotic obstruction (3/5) or poor opacification (2/5). 5/66 examinations were non-diagnostic owing to failure to image the central veins where no cause for fistula failure had been demonstrated. A further 5/66 examinations were non-diagnostic owing to failure to obtain oblique projections of the shunt where vascular details was obscured by overlapping vessels. The authors recommended routine imaging of the dialysis shunt in two planes and central venous imaging in all cases. This would have resulted in reduction of the failure rate from 16% to 1.5% in this series. IVDSA using a peripheral injection technique is simple, free from complications, and provides good quality images of both arterial and venous components of the fistula. Images of vessels not directly involved in fistula formation are routinely obtained and aid the planning of fistula revision.