Aortic Fistulas: A Pictorial Review

Aortic fistulas are rare but life-threatening vascular abnormalities characterized by abnormal communication between the aorta and an adjacent structure secondary to weakening of the vessel wall, such as in the setting of atherosclerosis or prior surgical intervention. Aortic fistulas can arise anywhere along the course of the aorta, with aortoenteric fistula being the most common type. Clinical presentation varies depending on the fistula type but often includes haemorrhagic symptoms such as hypotension, haematemesis, haematuria, and melena. Haemorrhagic shock and sepsis are common and often fatal complications. Prompt diagnosis is critical to reduce morbidity and mortality, and radiology plays a key role in diagnosis. CT angiography is the preferred imaging modality due to its rapid image acquisition and high spatial resolution. Radiologists must be able to recognize direct and indirect signs of aortic fistulas. In addition, differentiating aortic fistulas from mimics such as perigraft infection and inflammatory aortitis is essential for appropriate management.