Aortic Fistulas: Pathophysiologic Features, Imaging Findings, and Diagnostic Pitfalls

Fistulas between the aorta and surrounding organs are extremely rare but can be fatal if they not identified treated promptly. Most of these fistulas associated with a history trauma or vascular intervention. However, spontaneous aortic (AoFs) develop in patients weakened vasculature, which due to advanced atherosclerotic disease, collagen-vascular vasculitides, and/or hematogenous infections. The clinical features AoFs often nonspecific, presenting bleeding manifestations, back abdominal pain, fever, shock. Confirmation invasive endoscopy is impractical acute setting. Imaging plays an important role management AoFs, multiphasic multidetector CT angiography initial imaging examination choice. Obvious signs AoF include intravenous contrast material extravasation into fistulizing hollow organ, tract visualization, graft migration adjacent structure. nonspecific indirect such as loss fat planes ectopic foci gas seen more commonly. These confused other entities infection postoperative changes. Management may involve complex staged surgical procedures, depending on patient’s status, site fistula, presence infection, anticipated tissue friability. As endovascular interventions become common, radiologists will need have high index suspicion for this entity who aneurysms, repair, present bleeding. Online supplemental slide presentation from RSNA Annual Meeting available article. ©RSNA, 2021