The Thrombosed Type of Aortic Dissection-Its Clinical Features and Diagnosis.

In a previous report we stated that two distinct types of aortic dissection exist, namely, the opened-communicated type (O type) which demonstrates communication between the true lumen and the false lumen, and the thrombosed type (T type, also known as aortic dissecting hematoma or as intramural hematoma). The latter, in its acute phase, shows no opacification of the false lumen through medical imagings such as computed tomography (CT) scans or angiography. We analyzed the pathoclinical features of the acute phase. Over a period of 14 years, a study was conducted of 371 patients who were classified as O type and 95 who were classified as T type. The mean age was significantly higher in T-type patients and the sex ratio showed a significantly higher proportion of males. As for atherosclerotic risk factors, such as hypertension and diabetes, hypertension was frequently evident and more frequently seen in T-type patients. The incidence of Marfan's syndrome was 11%, and was not observed in T-type patients. In 18 T-type patients (19%), complications such as cerebral ischemic episodes were observed. However, they were transient and not serious, sometimes indicating only minor surgery.