Etiology of Thoracic Aortic Disease

Etiology of Thoracic Aortic DiseaseCauses of thoracic aortic disease include atherosclerosis, degenerative disorders of connective tissue (e.g., Marfan and Ehlers-Danlos syndromes and cystic necrosis), infection (e.g., syphilis), congenital defects (e.g., coarctation and congenital aneurysms of the sinus of Valsalva), trauma (e.g., penetrating and deceleration injuries), and inflammatory processes (e.g., Takayasu aortitis).The most common problem affecting the thoracic aorta is atherosclerotic aneurysm of the descending portion, accounting for about 20% of all aortic aneurysms. When such aneurysms dissect proximally, they may involve the aortic valve or coronary ostia. Distal dissection may involve the abdominal aorta with renal or mesenteric involvement.The next most frequent problem is traumatic disruption of the thoracic aorta. Adventitial false aneurysms may form distal to the left subclavian artery at the insertion of the ligamentum arteriosum, because of penetrating or deceleration injuries. These false aneurysms may dissect proximally and involve the arch and its major branches.