Angiographic demonstration of the causes of external arteriovenous haemodialysis shunt failure

The failure of chronic dialysis A-V shunts can usually be related to a cause of decreased flow rate which can be demonstrated by angiography. Examples of shunt failure due to mechanical defects in cannula position, foreign body reaction to the presence of the cannula, thrombosis due to a variety of reasons, unfavourable cannula placement proximal to entrance of a large venous tributary and arteriosclerotic degeneration of the vascular wall are illustrated. A decision to revise the shunt may be made on the basis of the angiographic findings.