Fatal secondary aortoduodenal fistula diagnosed with postmortem computed tomography angiography

Secondary aortoduodenal fistula (AEF), although less rare than its primary form, is an uncommon and frequently lethal cause of gastrointestinal (GI) bleeding. We report a case of fatal GI hemorrhage in a woman with a remote history of endovascular graft repair of an abdominal aortic aneurysm. Postmortem examination included computed tomography (PMCT) and CT angiography (PMCTA), which revealed air in the aorta, loss of the fat plane between the aorta and duodenum, and direct extravasation of contrast from the aorta into the duodenum. To our knowledge, this is the first published report of secondary AEF diagnosed by PMCT and confirmed with PMCTA. We propose a set of imaging criteria by which PMCTA can be used to supplant traditional anatomical dissection in the medicolegal investigation of deaths due to AEF.