Abdominal Aortic Aneurysm

Overview, Causes, & Risk Factors

Abdominal aortic aneurysm (AAA) is the term for enlargement and weakening of a portion of the abdominal aorta.

What is going on in the body?

The abdominal aorta is the main blood vessel that supplies blood to internal organs in the lower part of the body. Under certain conditions, a section of the aorta may weaken and swell. If the aneurysm should burst, large amounts of blood can be lost. This can quickly cause death. Blood can also leak in between the layers of the aorta and block arteries leading from it. This can cause serious damage to the organs supplied by those arteries.

What are the causes and risks of the condition?

The most common cause of AAA is atherosclerosis. In this condition, a fatty material builds up inside the aorta. This buildup causes inflammation and weakens the affected blood vessel.

Other causes of abdominal aortic aneurysms include:

  • injury, such as a crush injury from a motor vehicle accident
  • inherited conditions that cause weakened or abnormal blood vessel walls
  • infection carried in the bloodstream from other parts of the body

    • High blood pressure increases the risk of AAA. More than half of those diagnosed with AAA have high blood pressure. Cigarette smoking also increases the risk of AAA and can make AAA worse. Chronic coughing, such as the cough from chronic obstructive pulmonary diseases such as emphysema, can make the aneurysm worse.

    AAA is more common among Caucasian people. It affects men 4 times more often than women. It occurs most often in people between ages 60 and 90.