Background: The incidence of acute upper gastrointestinal bleeding (UGIB) has declined over the recent decades, and nowadays, due to improved endoscopic treatment options, only 2.6% of the patients with UGIB need additional surgical or angiographic intervention. In this report, we present the case of UGIB, refractory to endoscopic treatment, caused by a primary aortoesophageal fistula. Case Presentation: A 72-year-old man with acute UGIB was referred to our clinic after unsuccessful endoscopic and surgical treatment in an external hospital. On admission, the patient showed prolonged hemorrhagic shock and abdominal compartment syndrome. An immediately conducted thoracoabdominal CT scan revealed a penetrating aortic ulcer of the descending aorta and the patient was transferred to the OR to undergo laparotomy. After confirmation of a primary aortoesophageal fistula as the origin of hemorrhage, an aortic stent graft was successfully placed to occlude the lesion. Despite severe blood loss and prolonged hemorrhagic shock, the patient recovered quickly and could be discharged on the 18th postoperative day. Conclusion: Primary aortoenteric fistula is an uncommon clinical condition with a high mortality requiring an interdisciplinary treatment approach.

Keywords: Case report, upper gastrointestinal bleeding, penetrating aortic ulcer, primary aortoenteric fistula