The part of the aorta that lies in the abdomen is about one inch in diameter. This swelling is called an abdominal aortic aneurysm. As the aorta swells, its walls weaken and it may eventually burst, or rupture. Sudden ruptures often end in death. Abdominal aortic aneurysm has become increasingly common, especially in people over the age of 60.
Atherosclerosis is the most common cause of abdominal aortic aneurysms.
The muscular wall of the aorta weakens and begins to bulge. High blood pressure may speed up the weakening, but it is not the cause. Aneurysms tend to run in families, so there is the thought that genetics may play a role in who gets an aneurysm. There is a strong link between cigarette smoking and the occurrence of aneurysms. Smokers die four times more often from ruptured aneurysms than nonsmokers.