What is a dialysis fistula or graft?

What is a dialysis fistula or graft?

A surgically created connection between an artery and vein to allow for repeated vascular access for dialysis
Fistula: a direct connection between a native artery and a vein constructed by an end-to-end, end-to-side, or side-to-side anastomosis
Graft: a synthetic conduit (PTFE) inter-posed between an artery and a vein in a straight or looped configuration