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Arteriovenous fistula of the thoracic aorta: report of a case presenting with superior vena caval obstruction.

Injuries of the great vessels are frequently fatal. When death does not occur, the patient may present with massive haemorrhage, shock, or cardiac tamponade requiring urgent operation.1 If a major haemorrhage does not occur and the pat'ient survives, complications such as false aneurysm, mediastinal or cervical haematoma, haemothorax, coma, hemiplegia, or arteriovenous fistula may appear.2 Arteriovenous fistula involving the aorta is an extremely rare complication of thoracic trauma. Of 7500 American casualt'ies in South east Asia who suffered some type of vascular trauma, only 7% of the injuries resulted in arteriovenous fistulae and false aneurysms, none of them involving the thoracic aorta.3 Of 400 major arterial injuries treated over 20 years at a Los Angeles hospital, only one patient developed a fistula involving the thoracic aorta.4 A few other reports of arteriovenous fistulae of the aortic arch, mostly due to stab wounds, have been published; most of these patients presented with cardiac enlargement and cardiac failure.5-16 We report a patient, who, as a result of a knife wound, developed a fistula between the ascending aorta and the innominate vein and presented weeks later with superior vena caval obstruction.