An abdominal aortic aneurysm (AAA) is a bulging or ballooning out in the wall of the abdominal aorta. This large artery carries oxygen-rich blood from the heart to the lower portion of the body.

Aortic aneurysm kills about 15,000 people every year in the United States. It is more common among men than women, and the likelihood of developing an AAA increases with age. It is estimated that abdominal aortic aneurysms occur in up to 13 percent of all men and up to 6 percent of women over age 65. They are very rare among younger people.  

The causes of AAA are not known, but it is clear that smoking greatly increases a person’s risk of developing AAA. A family history of aneurysms also increases risk. In addition, high blood pressure (hypertension) and atherosclerosis is connected to aneurysm growth.

Most AAAs have no symptoms, which partially accounts for their high mortality rate.  When an aneurysm ruptures, it can result in massive internal bleeding and acute symptoms. Half of all patients with an AAA rupture die before they reach the hospital.

However, if detected before it ruptures an AAA can be treated surgically or with less invasive techniques. These techniques have a good success rate, so it is very important to identify and treat an AAA before rupture.