[Spontaneous Rupture of the Thoracic Aorta after Surgery of Rectal Cancer in an Elderly Patient；Report of a Case].

We reported a case of a 90-year-old man who underwent abdominoperineal resection of the rectum for advanced rectal cancer. On the 16th postoperative day, he suddenly lost consciousness during an exchange of the colostomy pouches. His heart arrested in a moment, and cardiopulmonary resuscitation was immediately performed, but in vain. The autopsy imaging revealed collapse of the heart and the thoracic aorta, as well as profuse blood-like effusion in the left pleural cavity. We considered that hemorrhagic shock due to spontaneous rupture of the thoracic aorta was the cause of his death.