Hardening of the arteries (atherosclerosis). Exactly how
atherosclerosis leads to abdominal aortic aneurysms is
unclear. It is thought that
atherosclerosis causes changes in the lining of the
artery wall that may affect oxygen and nutrient flow to the aortic wall
tissues. The resulting tissue damage and breakdown may lead to the development
Infections. Infections such as
endocarditis, an infection of the lining of the heart,
can cause aneurysms.
Injury. A sudden, intense blow to the chest or
abdomen, such as hitting the steering wheel in a car accident, can damage the
Inflammation. Inflammation of the aorta can weaken
the aortic wall. What causes the aorta to become inflamed is not clear.
Thoracic aortic aneurysms are much less common than
abdominal aortic aneurysms. They are often caused by
an abnormal breakdown of the elastic fibers in the aortic wall.
A pseudoaneurysm happens when a bulge occurs in the wall of the aorta. But the bulge doesn't affect all three layers of tissue in the wall of the aorta. This type of aneurysm might be caused by an injury.