An aortic aneurysm (say "a-OR-tik AN-yuh-rih-zum") is a bulge in part of the aorta, the body's main artery. When this bulge is in the belly (abdomen), it's called an abdominal aortic aneurysm. It's often called "triple A" or "AAA" for short.

These bulges are most common in men older than age 65, people with high blood pressure, and people who smoke. AAAs sometimes run in families.

Most aortic aneurysms never cause problems, especially if they're small, don't cause symptoms, and don't grow fast.

But if the bulge gets too big, it can burst, or rupture, which is often deadly.

When the bulge is small, not causing symptoms, and not growing fast, it is safe to watch it carefully and wait to have treatment. Small aneurysms rarely rupture.

Repair of the aneurysm is usually recommended if the AAA is large, causing symptoms, or is growing fast.

There are two ways to repair an aneurysm. One is traditional open surgery. The other is a less invasive procedure called endovascular repair, during which a tube called a stent graft is inserted through an artery in the groin.

Screening tests help your doctor look for a certain disease or condition before any symptoms appear. The AAA screening test is an ultrasound test. You lie on a table while a technician does the test. After the test, a radiologist looks at the pictures to see if you have an aneurysm.

AAA screening is fast and painless. It is usually done in the doctor's office or at a hospital.

• AAA screening can find large bulges that might rupture if they are not repaired.
• Screening can also find smaller bulges that can be watched carefully over the years.
• A study of men ages 65 and older showed that those who have the screening are less likely to die of AAA rupture.^{footnote 1}

It may seem obvious that AAA screening is good, because it might save your life by finding a bulge before it bursts. The test itself doesn't have risks. But what if you learn during the test that you have a bulge in your aorta? There's no way to know for sure if the bulge will rupture in the future. So you might decide to have surgery or a procedure to fix it. That's where the risks are.

Repairing an AAA can be very risky. The benefits outweigh the risks when the aneurysm is at risk of bursting. Repair of an AAA can cause problems later, like blood clots or problems with the stent graft in the aorta. And some people die during the operation or soon after.

• With open surgery (the surgeon makes a large cut in the belly and repairs the aorta), about 5 out of 100 people die during surgery or within 30 days.^{footnote 2} That means about 95 out of 100 people don't die during surgery or within 30 days.
• With an endovascular procedure, in which the surgeon inserts a tube called a stent graft through an artery in the groin, 1 or 2 out of 100 people die within 30 days.^{footnote 2} That means 98 or 99 out of 100 people don't die within 30 days.

You can see why it's so important to talk to your doctor about whether the benefits of AAA screening outweigh the risks in your case.

Not all doctors agree on who should be screened for abdominal aortic aneurysm. Talk to your doctor about whether the benefits of screening would outweigh the risks in your case.

The U.S. Preventive Services Task Force recommends a screening test for men who are ages 65 to 75 and have ever smoked.^{footnote 3}

Some doctors think that men 65 years and older should be screened if they have a family history of abdominal aortic aneurysm.

The U.S. Preventive Services Task Force does not recommend screening for women who have never smoked and have no family history of abdominal aortic aneurysm.^{footnote 3}

Women have a lower risk for an aneurysm than men do. But some doctors think that certain women should be screened. Some recommend screening for women who are 65 and older and either have smoked or have a family history of abdominal aortic aneurysm.