The many faces of aortoenteric fistulas.

Aortoenteric fistulas represent a life-threatening complication of abdominal aortic surgery that is becoming increasingly well-recognized. The presentation is often subtle, with a herald bleed followed by a period of grace, followed by an exsanguinating hemorrhage, and resulting in cardiovascular collapse. The diagnosis is often difficult, even with modern modalities of endoscopy, arteriography, and CAT scanning. A high index of suspicion is critical for making a successful diagnosis. The fistulas most commonly occur between the proximal aortic suture line and the duodenum after abdominal aortic surgery for aneurysmal or occlusive disease. Typically they occur years after this procedure. However, over the last several years, we have seen 12 cases with extremely unusual presentations that illustrate the wide spectrum of possible presentations. Included in this group was a primary aortoduodenal fistula, and two fistulas occurring just months after the initial surgery. These cases are reported with attention to the details of the presentation to emphasize the wide range of presentations of this serious complication. A brief review of this literature is also included in the report.