Abstract
Aortoenteric fistula (AEF) is an abnormal connection between the aorta and the adjacent gastrointestinal tract. Primary AEFs occur without previous aortic surgery, whereas secondary AEFs develop months to years after aortic procedures such as graft placement. Although rare, AEFs are a life-threatening cause of upper gastrointestinal bleeding that require prompt diagnosis and emergency management. Without timely treatment, the condition carries a high mortality rate. We present the case of a patient with massive upper gastrointestinal bleeding and hemorrhagic shock due to a secondary aortoduodenal fistula, occurring four years after placement of an interposition tube graft for an infrarenal aortic aneurysm. The patient was successfully managed through a multidisciplinary approach, combining endovascular aneurysm repair (EVAR) with open surgical intervention. This case highlights a rare and often overlooked cause of gastrointestinal hemorrhage in patients with a history of abdominal aortic surgery. The article discusses the pathophysiology, diagnosis, and management strategies for secondary AEFs.