Aortic dissection

Aortic dissection is a tear of the aorta (the largest artery of the body). This tear causes blood to flow between the layers of the wall of the aorta and dissects the layers apart. Aortic dissection is an extremely serious medical emergency and can quickly lead to death.

Etiology

Aortic dissection is associated with hypertension (high blood pressure) and many connective tissue disorders. Vasculitis (inflammation of an artery) is rarely associated with aortic dissection. It can also be the result of chest trauma. 72 to 80% of individuals who present with an aortic dissection have a previous history of hypertension.

Related Topics:
Hypertension - Connective tissue

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

The highest incidence of aortic dissection is in individuals who are 50 to 70 years old (in their 6th and 7th decade of life). The incidence is twice as high in males as in females (male-to-female ratio is 2:1). Half of dissections in females before age 40 occur during pregnancy (typically in the 3rd trimester or early postpartum period).

Related Topics:
Pregnancy - Trimester - Postpartum

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

A bicuspid aortic valve (a type of congenital heart disease involving the aortic valve) is found in 7-14% of individuals who have an aortic dissection. These individuals are prone to dissection in the ascending aorta. The risk of dissection in individuals with bicuspid aortic valve is not associated with the degree of stenosis of the valve.

Related Topics:
Bicuspid aortic valve - Congenital heart disease - Aortic valve - Stenosis

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Marfan syndrome is noted in 5-9% of individuals who suffer from aortic dissection. In this subset, there is an increased incidence in young individuals. Individuals with Marfan syndrome tend to have aneurysms of the aorta and are more prone to proximal dissections of the aorta.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Chest trauma leading to aortic dissection can be divided into two groups based on etiology: blunt chest trauma (commonly seen in motor vehicular accidents) and iatrogenic. Iatrogenic causes include trauma during cardiac catheterization or due to an aortic balloon pump.

Related Topics:
Motor vehicular accident - Iatrogenic - Cardiac catheterization - Aortic balloon pump

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Aortic dissection may be a late sequalae of cardiac surgery. 18% of individuals who present with an acute aortic dissection have a history of open heart surgery. Individuals who have undergone aortic valve replacement for aortic insufficiency are at particularly high risk. This is because aortic insufficiency causes increased blood flow in the ascending aorta. This can cause dilatation and weakening of the walls of the ascending aorta.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~