S1884 Secondary Aortoesophageal Fistula: Time to Improve Its Diagnosis

Abstract

INTRODUCTION: Secondary Aortoesophageal Fistula (SAEF) is an abnormal luminal communication between the aorta and the esophagus after an aortic surgical intervention. Its Mortality approaches 100% if left untreated. Aortic graft infection and erosion are the most common causes of SAEF. Due to its high mortality during the first few hours of presentation, SAEF should be recognized early as a cause of hematemesis. Despite improvement in imaging modalities, SAEF remains a difficult condition to diagnose in the acute setting especially in the presence of blood or clot obscuring the fistula during endoscopy (EGD). A high index of suspicion is mandatory as in our case. CASE DESCRIPTION/METHODS: Our patient is an 83-year-old female who had an aortic arch vascular graft for thoracic aortic aneurysm presented to the hospital after two episodes of hematemesis. 6 years after the surgery, the graft was infected and she was on chronic antibiotics. On admission, her hemoglobin was 5.3 g/dl, but she was hemodynamically stable. EGD was done and showed normal esophagus and fresh blood in the stomach. Upon further evaluation, an esophageal fistula was seen at 25 cm measuring 2 mm with minimal fresh blood. CT chest showed an air bubble around the descending aorta. She was deemed a poor surgical candidate given her age and chronic graft infection. The patient was transferred to another facility and underwent endovascular stent for palliation. The bleeding stopped but after several months her chronic infection led to septic shock and death. This is an atypical presentation with chronic intermittent bleeding and SAEF was difficult to diagnose as the air bubble seen on chest CT could be either from SAEF or abscess. DISCUSSION: SAEF should be considered as an etiology of massive hematemesis in patients with prior history of aortic graft. Patients can present with acute massive hematemesis with bright red blood, or less likely may have chronic mild intermittent upper gastrointestinal bleeding. SAEF diagnosis requires an attentive clinician who can combine the clinical picture with the diagnostics results. Although EGD should be done to evaluate for other causes of upper gastrointestinal diseases, SAEF can be missed during this procedure if hidden by bleeding or clot. The initial imaging modality of choice to detect SAEF is computed tomography (CT). CT can show an air bubble next to the graft which is a cardinal sign. However in this patient, the air bubble could be from a long standing infection, SAEF or both.Figure 1Figure 2Figure 3