**3.7 Blunt chest trauma**

The aortic area most commonly involved in blunt chest trauma is the proximal descending aorta, due to its relative mobility over fixed abdominal aorta which is held in place by ligamentum arteriosum. Usually an acute deceleration injury in motor vehicle accident leads to aortic rupture or dissection.

## **3.8 Aortic instrumentation or previous heart surgery**

Cardiac surgery or instrumentation for coronary or valvular heart diseases can be complicated by aortic tear, abnormal dilatation of aorta, and risk for aortic dissection [12].
