Angiographic diagnosis of aorto-inferior vena caval fistula.

Two cases of spontaneous aorto-caval fistula are reported. In the first, following laparotomy for an erroneous diagnosis of acute appendicitis, retrograde aortography was conclusive. In the second case, an attempted renal angiogram for acute renal failure and hematuria failed but a flush aortic injection showed the fistula.