胸骨骨折による外傷性上行大動脈損傷と遅発性心タンポナーデ

Traumatic Ascending Aortic Injury with Delayed Cardiac Tamponade due to Sternal Fracture

外傷性心タンポナーデは心外傷の中でも致死的な合併症であるが，遅発性に生じた報告は少ない．上行大動脈損傷による心タンポナーデは致死的であり，特に鋭的外傷によるものが多く，アイスピックなどによる損傷の報告が散見される．一方で鈍的外傷による上行大動脈損傷の報告は少なく，遅発性心タンポナーデとなるものはまれである．

The case was a 63-year-old male. He had a history of surgery for funnel chest at the age of 23. He overdrank and hit the anterior chest about two weeks before. He complained of persistent chest pain and palpitation, and was admitted because of atrial fibrillation and moderate pericardial fluid. Computed tomography （CT） showed a new sternal fracture, but dislocation and instability was mild. A few days later, sinus rhythm was restored and his heart failure improved. Unfortunately, on the 7th day, he suddenly suffered cardiopulmonary arrest. Ultrasonography revealed cardiac tamponade, and pericardiocentesis yielded 400 ml of bloody pericardial fluid collection. CT demonstrated clot mainly in the anterior pericardium, and emergent operation was performed. Bleeding from the anterior wall of the ascending aorta was repaired by placing one stitch. Postoperatively the patient remained unconscious, and CT of the brain showed hypoxic encephalopathy. After prolonged ventilator management, he was transferred to a rehabilitation hospital. In retrospect, the ascending aorta was close to the sternum in this patient, and sternal fracture might have caused injury of the ascending aorta.