Patient education: Thoracic aortic aneurysm (The Basics)

What is a thoracic aortic aneurysm? — 

A thoracic aortic aneurysm, or "TAA," 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 "thoracic aorta" is the upper part of the aorta. In people with a TAA, a part of the thoracic aorta gets weaker and balloons out or bulges.

A TAA can happen in different parts of the aorta (figure 1):

●"Ascending" thoracic aorta – This is the part that comes out of the heart and leads up toward the neck and arms.

●"Descending" thoracic aorta – This is the part that leads down toward the belly.

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

Some people have an aneurysm that also involves the lower part of the aorta, in the belly. This is called a "thoracoabdominal aortic aneurysm," or "TAAA" (figure 2).

What are the symptoms of a TAA? — 

Most people have no symptoms. Some people have pain in the chest, back, or belly.

Other symptoms are less common. They depend on how big the TAA is and which part of the thoracic aorta is affected. A TAA in the ascending aorta can cause heart problems.

If the TAA presses against other parts inside the body, symptoms might include:

●Cough, wheezing, or trouble breathing

●Hoarse voice

●Trouble swallowing

●Swelling of the face, neck, or arms

If the TAA is inflamed or infected, this can cause symptoms like fever or feeling very tired.

TAAs can burst with no warning. This can cause severe chest or back pain. It can also cause symptoms of low blood pressure, like dizziness or fainting. If you think your TAA might have burst, call for an ambulance (in the US and Canada, call 9-1-1).

Who is most likely to get a TAA? — 

Your risk for having a TAA goes up if you:

●Are male

●Smoke

●Have high blood pressure

●Have high cholesterol

●Have family members who have had a TAA

●Have another aneurysm, like an "abdominal aortic aneurysm" (which affects the lower part of the aorta) or a brain aneurysm

●Have had an "aortic dissection" (a tear in the inner wall of the aorta)

●Have a problem with the aortic valve, which is the valve that lets blood flow from the heart through the aorta

●Have inflammation or infection of the aorta

TAAs are more common in people with certain genetic conditions affecting the connective tissues. (Connective tissues make up and support the skin, bones, blood vessels, and other organs.) If you have one of these conditions, your doctor or nurse will talk to you about your risk of having a TAA. They will also decide if you should have regular testing.

People who take medicines to manage an aortic dissection have a higher risk for TAA. People with a TAA are also more likely to get an aortic dissection.

Is there a test for a TAA? — 

Yes. If a doctor thinks you might have a TAA, they will do an imaging test to look at your thoracic aorta. Imaging tests create pictures of the inside of the body. The most common tests for TAA are CT and MRI scans. They can show if you have a TAA, where it is, and how big it is.

Depending on your situation, you might need other tests, too. For example, if you have a TAA in the ascending aorta, your doctor will want to check how well your heart is working. In some cases, doctors find a TAA when a person gets an imaging test, such as a chest X-ray, for another reason.

How are TAAs treated? — 

It depends. If your TAA is small and you are not having any symptoms, you might not need treatment to repair it right away.

If your TAA does not need to be repaired, you need to:

●Get regular imaging tests – TAAs get bigger over time. These tests will show how quickly yours is getting bigger. You will get tests every 3 months to 1 year, depending on how big your TAA is. You might also get tests to check how well your heart is working.

●Take medicine to control your heart rate and blood pressure

●Call your doctor if you start having pain in your chest, back, or belly. Pain can be a sign the TAA is bursting.

People who have a TAA, 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.

If you have another condition related to your TAA, your doctor will decide if it needs treatment or tests.

When should TAAs be repaired? — 

Repair is the best treatment if your TAA is at risk of bursting. Your doctor can help you understand your risk based on:

●How large your TAA is

●How quickly your TAA is getting bigger

●Whether your TAA is affecting your heart

●Your other conditions or health problems

How are TAAs repaired? — 

Your options depend on where your TAA is, and how big it is. They also depend on your age, health, and other medical conditions.

The ways to fix a TAA are:

●"Open" surgery – If your TAA is in the ascending thoracic aorta (the part closest to the heart), it needs to be repaired with open surgery. For open surgery, the doctor makes a cut ("incision") in your chest to get to your aorta. They might make an incision in your belly if the abdominal aorta is also affected.

They will place clamps on your aorta to stop blood from flowing through. Then, they will replace the bulging part of your aorta with a tube called a "graft" (figure 3). The graft is made from a special fabric, and is sewn into place. After the clamps are removed, blood can flow normally through it. If there are problems with other parts of your aorta, its branches, or your heart valves, these can also be fixed during open surgery.

●Endovascular stent-graft – If your TAA is in the descending thoracic aorta (the part that goes toward the belly), you might be able to have an "endovascular" repair.

To fix the aorta this way, the doctor makes an incision in a blood vessel at the top of the thigh and inserts a folded graft. Then, they thread the graft up to the bulging part of your aorta and unfold it (figure 4). This type of graft does not need to be sewn into place. Blood flows through the graft.

●Combination (or "hybrid") repair – This might be an option in some situations. It involves open surgery to repair the ascending thoracic aorta, followed by an endovascular graft for the descending thoracic aorta.

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

Can TAAs 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 TAA or other problems.

More on this topic

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

Patient education: Abdominal aortic aneurysm (Beyond the Basics)