Aoic dissection is associated with

The factors that predispose to aoic dissection include systemic hypeension, a coexisting condition in 70% of patients, and cystic medial necrosis. Aoic dissection is the major cause of morbidity and moality in patients with Marfan syndrome ( Chap. 363 ) and similarly may affect patients with Ehlers-Danlos syndrome. The incidence also is increased in patients with inflammatory aoitis (i.e., Takayasu's aeritis, giant cell aeritis), congenital aoic valve anomalies (e.g., bicuspid valve), coarctation of the aoa, and a history of aoic trauma. In addition, the risk of dissection is increased in otherwise normal women during the third trimester of pregnancy. ref:Harrison&;s principles of internal medicine,ed 18,pg no 2063