Thirty vascular complications were seen in a group of 444 patients who had 516 arteriovenous fistulas for hemodialysis: 413 standard peripheral arteriovenous fistulas and 103 modifications, which included the use of 35 autogenous vein grafts and 62 bovine heterografts. Four hundred sixty-two of the fistulas were done with the radial or ulnar arteries, 53 with the brachial artery, and one with the superficial femoral artery. Symptomatic ischemia due to "steal" developed in eight patients (1.6%). Four of these patients developed gangrene, with one requiring finger amputation and three of them hand amputation. False aneurysms developed in 14 patients, ten infectious and four traumatic. Venous aneurysm requiring surgery developed in four patients and hand venous hypertension syndrome with chronic venous stasis in the hand was seen in four patients.