Ruptured thoracic descending aortic aneurysm coexisting with DeBakey type IIIb aortic dissection.

We have encountered a rare case of ruptured true thoracic aortic aneurysm coexisting with DeBakey type IIIb aortic dissection. The patient was a 67-year-old woman who had a past history of hypertension and cerebral infarction. She experienced DeBakey type IIIb acute aortic dissection, and initially conservative medical treatment was carried out. However, the patient suddenly went into shock, and emergency contrast-enhanced computed tomography revealed the presence of a ruptured true thoracic aortic aneurysm coexisting with the type IIIb dissection. Replacement of the descending aorta was performed through a left thoracotomy using circulatory arrest and deep hypothermia. The rupture site and intimal tear were located in the middle of the aneurysm. Open proximal and distal anastomoses were carried out using a 22 × 10 mm gelatin-covered Dacron graft. The patient was discharged from our hospital uneventfully on the 33rd postoperative day.