Patient education: Abdominal aortic aneurysm (The Basics)

What is an abdominal aortic aneurysm? — 

An abdominal aortic aneurysm, or "AAA," is a problem in the aorta. The aorta is the main blood vessel that comes out of the heart. Blood flows through the aorta to the rest of the body.

The "abdominal aorta" is the part of the aorta that is located in the belly. It branches to bring blood to the organs in the belly and the legs. In people with an AAA, a part of the abdominal aorta gets weaker and balloons out or bulges (figure 1).

If an AAA bursts, it is very dangerous. A burst aorta causes lots of internal bleeding.

What are the symptoms of an AAA? — 

Most people have no symptoms.

When symptoms do occur, they can include:

●Pain in the belly or back – This can happen if the AAA gets bigger quickly.

●A small lump in the upper part of the belly that pulses (this means it swells and shrinks in rhythm with the heartbeat) – Doctors notice this more often than patients do.

●Fever, or feeling very tired – These can happen if the AAA is inflamed or infected.

AAAs can burst with no warning. This can cause sudden, severe belly pain. It can also cause other symptoms, like pain in the groin or down the inner leg or dizziness or fainting from low blood pressure.

If you think your AAA might have burst, call for an ambulance (in the US and Canada, call 9-1-1).

Who is most likely to get an AAA? — 

Your risk for having an AAA goes up if you:

●Smoke

●Are male

●Are older than 60

●Have had an "aortic dissection"

●Have family members who have had an AAA or a related condition like a thoracic aortic aneurysm ("TAA") or aortic dissection

●Have other aneurysms, like one behind the knee

●Have inflammation or infection of the aorta – An infection in a heart valve can lead to infection in the aorta.

Is there a test for an AAA? — 

Yes. If you are at high risk for having an AAA, or if you have symptoms of an AAA, your doctor can do tests.

The most common test to look for AAA is called an "abdominal ultrasound." For this test, a tool called a "probe" is passed over your belly. The probe uses sound waves to create a picture of your aorta. This can show if you have an AAA or another problem. Your doctor will also do an exam and check the pulses in your legs.

How are AAAs treated? — 

It depends on the cause and how big the AAA is. Some people need a procedure to repair it. Others do not.

You might not need to have your AAA repaired right away if it is small, is not changing, and is not infected.

If your AAA does not need to be repaired, you will need to:

●Get regular tests to see if the AAA is getting bigger, and how fast – Your doctor will tell you how often you should get tested based on the size of your AAA.

●Take medicine to control your blood pressure

●Call your doctor if you have symptoms that might mean your AAA has burst – The most common symptom is sudden, severe belly or back pain. A burst aneurysm can also cause other symptoms, like pain in the groin or down the inner leg or dizziness or fainting from low blood pressure.

People who have an AAA, even a small one, are at increased risk for heart disease. Your doctor can talk to you about ways to help lower your risk. This might include improving your diet, exercising more, and quitting smoking if you smoke.

When should AAAs be repaired? — 

Repair is the best treatment if your AAA is at risk of bursting. This is more likely if your AAA:

●Is causing any symptoms

●Is bigger than 5.5 centimeters (2.2 inches) wide

●Gets more than 0.5 centimeters (0.2 inches) bigger in 6 months

How are AAAs repaired? — 

AAAs can be fixed in 1 of 2 ways (figure 2):

●"Open" surgery – The doctor makes a cut ("incision") in your belly and replaces the bulging part of your aorta with a tube called a "graft." The graft is made from a special material and is sewn into place. Blood can flow normally through it.

●Endovascular stent graft – The doctor makes an incision in your blood vessel at the top of your thigh and inserts a folded graft. Then, they thread the graft up to the bulging part of your aorta and unfold it. This type of graft does not need to be sewn into place. Blood flows through the graft.

If your AAA needs to be repaired, your doctor will talk to you about your options, the risks, and what to expect.

Can AAAs be prevented? — 

No. But you can greatly reduce your risk by not smoking. If you have high blood pressure, it is also important to control your blood pressure.

If you get an infection, follow all instructions about treatment. This can help lower the risk of AAA or other problems.

More on this topic

Patient education: Aortic aneurysm repair (The Basics)
Patient education: Aortic dissection (The Basics)
Patient education: Thoracic aortic aneurysm (The Basics)
Patient education: Abdominal ultrasound (The Basics)

Patient education: Abdominal aortic aneurysm (Beyond the Basics)