Superior mesenteric arteriovenous fistula presenting as gastrointestinal bleeding: case report and literature review.

Superior mesenteric arteriovenous fistula (SMAVF) is a rare vascular disorder usually following penetrating abdominal trauma or gastrointestinal surgery. Percutaneous endovascular treatment such as embolization, has been widely used to treat this disease. We report a patient, who was presented with melena at the onset of his symptoms, then an acute hematemesis in shock.