Which is the most common cause of acquired aeriovenous fistula?

Acquired aeriovenous fistulas are caused by aificial connections between adjacent aeries and veins. Penetrating injuries are the most common cause of acquired aeriovenous fistula. Other causes includes creating vascular access for hemodialysis, as complications of aerial catheterization or surgical dissection and rarely it can be caused by rupture of an aerial aneurysm into a vein. Ref: Bailey and Love Sho Practice of Surgery, 25th Edition, Page 596; Harrison's Principles of Internal Medicine, 18th Edition, Chapter 249.