Aortoesophageal Fistula Following Thoracic Endovascular Aortic Repair

To The Editor, Upper gastrointestinal bleeding (UGIB) and hematemesis commonly result from peptic ulcer disease and esophageal varices, and the possibility of a vascular etiology is often not considered in the differential diagnosis. Aortoesophageal fistula (AEF) is a life-threatening vascular cause of UGIB with the potential risk of exsanguination and death.[1] Most primary AEFs result from the rupture of an aneurysm of the descending thoracic aorta (DTA) into the esophagus.[2] Secondary AEFs generally result from prior vascular interventions. A 46-year-old male, with a history of thoracic endovascular aortic repair (TEVAR) performed 2 years ago for type B aortic dissection, presented with recurrent hematemesis, fever, and chest pain. His vital signs were normal. Blood investigations showed anemia (hemoglobin 7.5 gm/dl) and leukocytosis. A chest x-ray showed mediastinal widening and the presence of a stent graft in the DTA. Upper gastrointestinal endoscopy performed at the previous hospital showed a suspicion of AEF at the lower end of the esophagus. A positron emission tomography-computed tomography (CT) scan of the chest showed a TEVAR stent in the DTA from the D6–D10 level with features of stent graft infection. CT chest with oral contrast demonstrated AEF at the upper end of the TEVAR device [Figure 1a]. The case was discussed with a multi-disciplinary team, and it was decided to perform surgery in two stages after obtaining informed consent. In the first stage, the thoracic team performed cervical esophagostomy and decompression of the distal intrathoracic esophagus, followed by division of the gastroesophageal junction and feeding gastrojejunostomy by the gastrointestinal team. After 7 days, the second-stage surgery consisting of esophagectomy [Figure 1b and c], explanation of the infected TEVAR device [Figure 1d], excision of the diseased DTA, and its replacement with the interposition graft (Intergard Woven 24 mm × 30 cm, Intervascular Sas, France), was performed under hypothermic cardiopulmonary bypass. The immediate postoperative course was unremarkable. On the eighth postoperative day, the patient had a sudden cardiovascular collapse. The chest was reopened, and a massive secondary hemorrhage just distal to the distal anastomotic suture line was noted. Unfortunately, the bleeding could not be controlled, and the patient succumbed to fatal exsanguination.Figure 1: Computed tomography with oral contrast demonstrating an aortoesophageal fistula (red circle) in the coronal plane (a). Surgical photographs showing resected specimens of the esophagus and the aorta (b), fistulous communication between the esophagus and the aorta (arrow, c), and the removed infected TEVAR (thoracic endovascular aortic repair) stent graft (d)The case described here highlights the importance of considering the differential diagnosis of AEF when evaluating patients presenting with hematemesis. The predisposing risk factors for AEF include prior aortic or esophageal surgeries, interventional graft placements, aortic aneurysms, or thoracic malignancies. The incidence of AEF is approximately 0.07%, but the mortality rate, even after surgical intervention, is over 55%.[3] To establish the diagnosis of AEF, CT angiography is the investigation modality of choice, as it can objectively demonstrate extravasation of the contrast agent. No treatment guidelines have been described for AEF.[4] The definitive treatment of AEFs is usually a combination of aortic (TEVAR, graft replacement, graft repair) and esophageal (esophagectomy, esophageal stent, esophageal repair) surgeries.[5] The main drawback of TEVAR includes the formation of a nidus for infections and subsequent stent graft infection, as happened in this patient. Open surgery allows for the debridement of the infected mediastinum and esophageal repair in addition to aortic wall reconstruction. In conclusion, AEF is a rare and life-threatening cardiovascular cause of UGIB. It should be included in the list of differential diagnoses when evaluating patients presenting to the emergency room with hematemesis, especially if they have predisposing risk factors. Stent graft infection leading to AEF formation can be treated by open surgery, but the mortality remains high. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.