**3.2 Hypertension**

Systemic hypertension is the most important predisposing condition for aortic dissection. It could be either an acute, transient, abrupt rise in blood pressure leading to aortic dissection by various mechanisms like strenuous resistance exercises, weight lifting or illicit use of drugs like cocaine, egotism, and energy drink usage [7, 8]. While chronic or long-term hypertension keeps greater pressure on atherosclerotic arterial walls, leading to intimal tear and aortic aneurysm.

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*Aortic Dissection*

**3.3 Genetic disorders**

*DOI: http://dx.doi.org/10.5772/intechopen.89210*

syndrome and aortic dissection [9].

**3.6 Inflammatory or infectious conditions**

of elastic support and vessel dilatation.

motor vehicle accident leads to aortic rupture or dissection.

**3.8 Aortic instrumentation or previous heart surgery**

bolic state and hormonal effects on the vasculature.

**3.7 Blunt chest trauma**

dissection [12].

**3.9 Pregnancy and delivery**

**3.4 Bicuspid aortic valve**

**3.5 Coarctation of aorta**

aortic dissection.

People having specific genetic conditions have a higher incidence of aortic dissection, like Marfan's syndrome, Turners syndrome, Ehlers-Danlos syndrome, annuloaortic ectasia, adult polycystic kidney disease, Noonan syndrome, and osteogenesis imperfecta. Mostly patients with Marfan's syndrome who develop aortic dissection are young, around 40 years old, and have family history of Marfan's

Bicuspid aortic valve usually leads to aortic dissection of ascending aorta, because of severe loss of elastic fibers in the media wall. Patients with bicuspid valves associated with aortic dissection are younger below 40 years age [10].

The most common area for congenital coarctation of aorta is the site of ductus arteriosus, where the aorta is focally narrowed. That area is usually underdeveloped, hypoplastic, and small, affecting the layers of the aorta, and increases the risk for

Inflammatory or infectious diseases that lead to vasculitis (like giant cell arteritis, rheumatoid arthritis, takayasu arteritis, syphilitic aortitis, etc.) affect the vaso vasorum or small arteries that supply blood to the aortic wall [11]. When these small arteries are compromised, they lead to the ischemic injury to the aortic wall and predisposes to aortic dissection. For example, in tertiary syphilis, inflammation begins at adventitia of the aortic arch leading to obliterative endarteritis of the vasa vasorum, luminal narrowing, ischemic injury of medial aortic arch, and finally loss

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

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

Both pregnancy and delivery are independent risk factors for aortic dissection [13], but with the presence of other connective tissue diseases like Marfan's syndrome or bicuspid aortic valve, the risk usually multiplies. In pregnancy, aortic dissection occurs most commonly in third trimester due to hyper dynamic meta-
