[Thoracic aortic aneurysm. Pathologico-anatomical analysis of 111 cases]

Only about 8% of all aortic aneurysms are localized in the thoracic segment. They are mainly due to degenerative diseases of the media (medianecrosis and mucoid degeneration); predominating in the ascending aorta, they possess a marked tendency to wall dissection. Their frequency decreases in the distal direction. On the other hand, arteriosclerotic aneurysms are rare in the proximal aortic segments and predominate more in the distal direction. Aneurysms due to inflammatory diseases are found mainly in the aortic arch and the descending thoracic aorta. About half of them are dissecting.