[A case of a chronic traumatic thoracic aneurysm with compression of left main bronchus at the isthmus].

We report a case of traumatic thoracic aortic aneurysm found by occurrence of pulmonary atelectasis in the chronic phase. The patient, an 18-year-old female, was hospitalized with multiple trauma caused by a traffic accident. At the time of hospitalization, no thoracic trauma was found but a fracture of the pelvis and one leg was recognized. 45 days after the initial trauma, a pulmonary atelectasis on the left lung was found on a chest X-ray film. By chest CT and angiography, the pulmonary atelectasis was proved to be caused by compression of the left main bronchus by a traumatic aneurysm of the thoracic aorta. 55 days after the initial trauma, resection of the aneurysm and graft replacement was performed. Postoperative course was satisfactory. In conclusion, possibility of an injury to the thoracic aorta should be considered on the treatment for the patient with multiple trauma in the chronic phase as well as in the acute phase.