The aorta is the main blood vessel that supplies blood to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs when an area of the aorta becomes very large or balloons out.
The exact cause of an aneurysm is unknown. It occurs due to weakness in the wall of the artery. Factors that can increase your risk of having the problem include:
- High blood pressure
- Male gender
- Genetic factors
An abdominal aortic aneurysm is most often seen in males over age 60 who have one or more risk factors. The larger the aneurysm, the more likely it is to break open or tear. This can be life-threatening.
Aneurysms can develop slowly over many years, often with no symptoms. Symptoms may come on quickly if the aneurysm expands rapidly, tears open or leaks blood within the wall of the vessel (aortic dissection).
Symptoms of rupture include:
Exams and Tests
Your health care provider will examine your abdomen and feel the pulses in your legs. The provider may find:
- A lump (mass) in the abdomen
- Pulsating sensation in the abdomen
- Stiff or rigid abdomen
You may have an abdominal aortic aneurysm that is not causing any symptoms. Your provider may find this problem by doing the following tests:
- Ultrasound of the abdomen when the abdominal aneurysm is first suspected
- CT scan of the abdomen to confirm the size of the aneurysm
- CTA (computed tomographic angiogram) to help with surgical planning
Any one of these tests may be done when you are having symptoms.
If you have bleeding inside your body from an aortic aneurysm, you will need surgery right away.
If the aneurysm is small and there are no symptoms:
- Surgery is rarely done.
- You and your doctor must decide if the risk of having surgery is smaller than the risk of bleeding if you do not have surgery.
- Your doctor may want to check the size of the aneurysm with ultrasound tests every 6 months.
Most of the time, surgery is done if the aneurysm is bigger than 2 inches (5.5 cm) across or growing quickly. The goal is to do surgery before complications develop.
There are 2 types of surgery:
- Open repair: A large cut is made in your abdomen. The abnormal vessel is replaced with a graft made of man-made material.
- Endovascular stent grafting: This procedure can be done without making a large cut in your abdomen, so you may recover more quickly. This may be a safer approach if you have certain other medical problems or are older adults. Endovascular repair can sometimes be done for a leaking or bleeding aneurysm.
The outcome is often good if you have surgery to repair the aneurysm before it ruptures.
When an abdominal aortic aneurysm begins to tear or ruptures, it is a medical emergency. Only about 1 in 5 people survive a ruptured abdominal aneurysm.
When to Contact a Medical Professional
Go to the emergency room or call 911 if you have pain in your belly or back that is very bad or does not go away.
To reduce the risk of aneurysms:
- Eat a heart-healthy diet, exercise, stop smoking (if you smoke), and reduce stress.
- If you have high blood pressure or diabetes, take your medicines as your doctor has told you.
People over age 65 who have ever smoked should have a screening ultrasound done once.
Aneurysm - aortic; AAA
Braverman AC. Diseases of the aorta. In: Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 10th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 57.
Fairman RM, Wang GJ. Abdominal aortic aneurysm. In: Cronenwett JL, Johnston W, eds. Rutherford's Vascular Surgery. 8th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 132.
Tracci MC, Cherry KJ. The aorta. In: Townsend CM Jr, Beauchamp RD, Evers BM, Mattox KL, eds. Sabiston Textbook of Surgery. 19th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 62.
Update Date 8/13/2015
Updated by: Deepak Sudheendra, MD, RPVI, Assistant Professor of Interventional Radiology & Surgery at the University of Pennsylvania Perelman School of Medicine, with an expertise in Vascular Interventional Radiology & Surgical Critical Care, Philadelphia, PA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.