[A case report: reopacified thrombosed dissection of Stanford type A].

A 60-year-old male, who had been hospitalized with a Stanford type B acute aortic dissection 3 years ago, was admitted with severe disquiet caused by discomfort of the chest and the neck. Enhanced CT scans demonstrated the ascending aorta compressed by non-opacified false lumen, so-called "thrombosed dissection" or "closing aortic dissection", and normal descending aorta. Aortography showed no intimal tear in the ascending aorta and aortic arch. "Hibernation therapy" with pentobarbital was performed to be sedated over during 13 days. 29 days later follow-up CT scans showed reopacified false lumen and enlargement of the ascending aorta, although he had no complaints during the medical therapy. Large intimal tear just under the brachiocephalic artery and giant false lumen without reentry occupying the ascending aorta was found by the repeat aortography. Graft replacement of the ascending aorta was successfully performed. This case suggested that thrombosed dissection might have the risk of recanalization of clotted false lumen asymptomatically, and it would be important to take care of radiographic changes during the medical therapy even if the patient had no symptoms.