An 18-year-old soldier had a gunshot wound to his left thigh during the Mexican Civil War (1910-1917). He presented with persistent bright red bleeding. His wound was treated by compression. A few years after the injury, he noticed a thrill, large varicose veins, limb swelling, and skin changes. A plain film showed an 8 x 10-cm midthigh mass. After a bullfighting incident, the pseudoaneurysm ruptured. Because of increased bulk and discomfort, the patient agreed 3 years later to be treated. Angiography showed a chronically obstructed femoral artery and vein. A 3000-mL hematoma was evacuated. This case illustrates the long-term sequelae of an arteriovenous fistula. This report describes a 51-year delay of treatment for causes unrelated to diagnosis. To our knowledge, this case is the longest delay in treatment of an arteriovenous fistula and its complications reported in the literature.