Pathological investigation of graft-related oesophageal fistula.

Oesophageal fistulae after thoracic endovascular aneurysm repair (TEVAR) for thoracic aortic aneurysm (TAA) have been reported, although the causes are unknown. One hypothesis is that the structural configuration of the aortic aneurysm, as it protrudes towards the oesophagus, may affect oesophageal fistula formation. The pathological findings of an oesophageal fistula following TEVAR are reviewed here. This report presents the case of a 68-year-old man with a stent graft-related oesophageal fistula after TEVAR for TAA. The oesophageal fistula suddenly appeared on the 11th day after TEVAR, and oesophagectomy was performed, without stent graft extirpation. The pathological findings showed neutrophil infiltration from the adventitia to the mucosa and congestion in the capillaries of the oesophageal wall around the site of penetration and no bacterial infection. There have been reports with logical hypotheses about the causes of stent graft-related oesophageal fistulae. Our pathological findings support the theory that pressure necrosis or ischaemic insult by physical compression of a rigid thrombosed aneurysm may result in fistula formation. For descending aortic aneurysms that protrude toward the oesophagus, caution must be exercised to prevent oesophageal fistula formation after TEVAR.