Morphological investigations of type A aortic dissection

The aim of this study was to analyze systematically the morphology of aortal segments of Type A dissection. Nineteen patients were operated on for Type A dissection in the Department of Thoracic, Cardiac, and Vascular Surgery in Goettingen, Germany, from January 2002 to January 2005. All diagnoses were confirmed by transesophageal echocardiography and computed tomography of the chest. All taken aortic segments were examined by the conventional histological and electron microscopical method. Besides subadventitial hyperplasia of collagen filaments, the preparations showed hyperplasia of endothelial cells with loose cellular junctions, desquamation of endothelial cells, and morphological changes of endothelial cells with villius development, as well as signs of aortitis. The present results arouse suspicion of local inflammation of the aortic wall, but with moderate progress under strong hyperplasia. Because of rupture of the intima, the inflammation appears as an acute disease.