Your heart pumps blood into your aorta—the largest artery in your body. The aorta carries oxygen-rich blood from the heart to your entire body.

Sometimes the wall of the aorta can weaken. If this happens, the wall expands because of the constant pressure of blood flowing against it and may bulge or balloon out. This condition is called an aortic aneurysm. It can happen in your chest (thoracic aortic aneurysm) or abdomen (abdominal aortic aneurysm).

If you’ve been told you have an aortic aneurysm, it probably took you by surprise. Usually there are no symptoms. The aneurysm is often found by chance on imaging tests that were ordered to rule out other problems. Still, it can be a scary diagnosis. As the aneurysm gets bigger, it can burst, causing internal bleeding that is nearly always fatal. But through careful monitoring, you and your health care team can keep close tabs on the aneurysm to figure out the best course of action—one that helps you live a long, active life. 

Treatment depends on the location, size and cause of the aneurysm and how fast it is growing.  Treatment may include careful monitoring, surgery, medications, and/or lifestyle changes. Use this condition center to learn more about living with aortic aneurysm. You can also read about the latest research, create a list of questions to ask your doctor and much more.

Overview

An aortic aneurysm occurs when a section of the aorta, the body’s main artery, becomes enlarged. The aorta carries blood and nutrients (fuel) from the heart (the engine of the body) to the rest of the body.

Because the aneurysm can stretch and weaken like a balloon, it can burst. If the aorta bursts, it can cause serious internal bleeding that can be fatal.

The aorta looks like a walking cane. The first part is the ascending aorta. The second portion is the arch. The third portion is the descending aorta. Aneurysms can form in any section of the aorta.

When one forms in the belly area—the most common location—it is called an abdominal aortic aneurysm. When one forms in the upper body, it is called a thoracic aortic aneurysm.

Causes

The wall of a normal aorta stretches like a balloon. It can expand and contract depending on blood flow. The wall of your aorta can become stiff because of hardening of the arteries (atherosclerosis) often caused by high blood pressure, cholesterol, or age. These conditions also can weaken the aorta wall and cause it to bulge.

Other less common causes of aortic aneurysm include:

• People who have problems with the structure of the aortic wall that are inherited (for example Marfan syndrome and other less common diseases)
• People born with a bicuspid aortic valve (they have two aortic valve leaflets instead of the normal three), which is associated with aortic aneurysms
• Syphilis
• Turner syndrome (genetic disease)
• Inflammation of the wall of the aorta (aortic arteritis)
• Aortic dissection
• Trauma, such as a hard hit to the chest that damages the aorta.