Abdominal Aortic Aneurysm (AAA)
The aorta is the largest blood vessel in the human body. It carries blood from your heart down to your abdomen, legs, and pelvis. The walls of the aorta can swell or bulge out like a small balloon if they become weak. This is called an abdominal aortic aneurysm (AAA) when it happens in the part of the aorta that’s in your abdomen.
AAAs don’t always cause problems, but a ruptured aneurysm can be life-threatening. Therefore, if you’re diagnosed with an aneurysm, your doctor will probably want to monitor you closely, even if they don’t intervene right away.
AAAs are usually classified by their size and the speed at which they’re growing. These two factors can help predict the health effects of the aneurysm.
Small (less than 6 centimeters) or slow-growing AAAs generally have a much lower risk of rupture than larger aneurysms or those that grow faster. Doctors often consider it safer to monitor these with regular abdominal ultrasounds than it is to treat them.
Large (greater than 7 centimeters) or fast-growing AAAs are much more likely to rupture than small or slow-growing aneurysms. A rupture can lead to internal bleeding and other serious complications. The larger the aneurysm is, the more likely it will need to be treated with surgery. These types of aneurysms also need to be treated if they’re causing symptoms or leaking blood.
The cause of AAAs is currently unknown. However, certain factors have been shown to increase your risk for them. They include:
High Blood Pressure (Hypertension)
Blood pressure refers to the level of pressure on the walls of your blood vessels. High blood pressure can weaken the walls of your aorta. This makes an aneurysm more likely to form.
Smoking can directly damage the walls of your arteries, making them more likely to bulge. It can also increase your risk of high blood pressure.
Vascular Infection (Vasculitis)
Serious infections within the aorta and other arteries can occasionally cause AAAs. However, this happens very rarely.
Aneurysms can form in any blood vessel in your body. However, AAAs are considered particularly serious because of the size of the aorta.
AAAs are more likely to occur if you:
- are male
- are obese or overweight
- are over age 60
- have a family history of heart conditions and diseases
- have diabetes
- have high blood pressure, especially if you’re between 35 and 60 years old
- have high cholesterol or fatty buildup in the blood vessels (atherosclerosis)
- live a sedentary lifestyle
- have had trauma to your abdomen or other damage to your midsection
- smoke tobacco products
Most aneurysms have no symptoms unless they rupture. If an AAA does rupture, you may experience one or more of the following symptoms:
- sudden pain in your abdomen or back
- pain spreading from your abdomen or back to your pelvis, legs, or buttocks
- clammy or sweaty skin
- increased heart rate
- shock or loss of consciousness
Call your doctor immediately if you experience any of these symptoms. A ruptured aneurysm can be life-threatening.
AAAs that haven’t ruptured are most often diagnosed when a doctor is scanning or examining your abdomen for another reason.
If your doctor suspects that you may have one, they will feel your stomach to see if it’s rigid or contains a pulsing mass. Your doctor may also check the blood flow in your legs. They might even use one of the following tests to scan your abdomen and look for one:
- CT scan of the abdomen
- abdominal ultrasound
- chest X-ray
- abdominal MRI study
Depending on the size and exact location of the aneurysm, your doctor may perform surgery to repair or remove the damaged tissue. This may be done either with open abdominal surgery or endovascular surgery. The surgery performed will depend on your overall health and the type of aneurysm.
Open abdominal surgery is used to remove damaged areas of your aorta. It’s the more invasive form of surgery and has a longer recovery time. Open abdominal surgery may be necessary if your aneurysm is very large or has already ruptured.
Endovascular surgery is a less invasive form of surgery than open abdominal surgery. It involves using a graft to repair the weakened walls of your aorta.
For a small AAA that’s less than 4 centimeters wide, your doctor may decide to monitor it regularly instead of performing surgery. Surgery has risks, and small aneurysms generally don’t rupture.
If your doctor recommends open abdominal surgery, it may take up to six weeks to recover. Recovery from endovascular surgery, however, only takes two weeks.
The success of surgery and recovery greatly depends on whether or not the AAA is found before it ruptures. Prognosis is usually good if the AAA is found before it ruptures.
Focusing on heart health can help prevent an AAA. This means watching what you eat, exercising, and avoiding other cardiovascular risk factors such as smoking. Your doctor might also prescribe medicines to treat high blood pressure or cholesterol or to help you control your diabetes.
Your doctor may want to screen you for an AAA when you turn 65 if you’re at a higher risk due to smoking and other factors. The screening test uses an abdominal ultrasound to scan your aorta for bulges. It’s painless and only needs to be performed once.
Written by: Brindles Lee Macon and Elizabeth Boskey, PhD
Published on Jul 16, 2012
Medically reviewed on Aug 01, 2017 by Daniel Murrell, MD