Primary internal Iliac Aneurysm-Rectal Fistula treated with a combined endovascular and endoscopic approach as a palliative strategy: a case report

Background A primary aortoenteric fistula (AEF) is a pathologic communication between the aorta and the gastrointestinal tract. Although uncommon, this condition carries a substantial risk of life-threatening hemorrhage. Case presentation An 82-year-old male with a history of coronary artery disease and chronic obstructive pulmonary disease (COPD) presented to the emergency department with acute gastrointestinal bleeding. Computed tomography (CT) revealed bilateral common iliac artery aneurysms and left internal iliac artery aneurysm. In addition, the rectal wall demonstrated heterogeneous thickening with an apparent focal discontinuity along the proximal left lateral wall, suggestive of a fistulous tract between the left internal iliac artery and the rectum. Emergency intervention was performed, which included embolization of the inflow and outflow tracts of the left internal iliac artery aneurysm using fibered coils, followed by deployment of a covered stent from the origin of the left common iliac artery to the left external iliac artery. The patient experienced recurrent gastrointestinal bleeding postoperatively, which was managed with endoscopic hemostasis. He was discharged on postoperative day 15 after the initial procedure and remained well during a 7-month follow-up period. Conclusion Early and accurate diagnosis of aortoenteric fistula is paramount. Endovascular repair combined with endoscopic hemostasis can serve as an effective bridging or palliative strategy to stabilize patients and create a window for definitive surgery, despite this patient demonstrated a favorable short-term outcome.