An aneurysm is an abnormal bulge or ballooning of an artery, caused by the weakening of the artery wall. Aneurysms most commonly occur in the abdominal aorta, which is the major artery in the lower half of the body that carries oxygenated blood from the heart to the rest of the body. When these aneurysms rupture, there is the potential for fatal bleeding.

Many patients with aneurysms of the aorta have no symptoms, causing the condition to remain undiagnosed until the aneurysm ruptures. Other aneurysms are discovered during computed tomography (CT) or magnetic resonance imaging (MRI) scans that are performed for other health problems.

Some patients have mild symptoms of pain or discomfort in the area of the aneurysm. Severe abdominal, back or groin pain in a patient with an aneurysm could be due to a ruptured aneurysm and should be treated immediately.

Almost all aneurysms can be detected with safe and painless non-invasive tests, such as ultrasound studies or computed tomography (CT) scans.

Large aneurysms may require surgery while small ones are closely monitored with ultrasound and may never grow large enough to require surgery.

Aneurysms of the aorta that are large enough to require repair are treated with one of the following:

  • Conventional Surgery — A synthetic graft is sewn inside the aneurysm to the artery above and below it to prevent the aneurysm from rupturing.
  • Endovascular Repair — A newer procedure that uses a catheter inserted in the groin to guide a self-expanding graft to the aneurysm. Endovascular repair does not require an abdominal incision and has a substantially shorter recovery. Not all aneurysms are suitable for endovascular repair.

Smaller aneurysms are monitored with ultrasound tests to watch their growth. Many never enlarge to a size that requires repair.

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