A case of aortic dissection caused by blunt chest trauma

A 74-year-old woman was struck by a car travelling at about 50km/h. On arrival at hospital, a CT scan showed dissection of the ascending and descending aorta. She collapsed and died suddenly 8h later. At autopsy, there was massive bleeding into the left pleural cavity, ruptures of the pericardium and right ventricle, and a type A thoracic aortic dissection. The cause of death was haemorrhagic shock due to rupture of the pericardium and delayed rupture of the right ventricle following trauma to the chest. The thoracic aortic dissection was not the direct cause of death although histological examination did reveal that it occurred in the accident. Traumatic aortic dissection is rare although traumatic aortic rupture is a major cause of death after blunt chest trauma. This paper discusses the mechanisms, and factors involved in aortic dissection caused by blunt trauma.