Thoracic aortic aneurysm

Expert reviewer, Mark Yeatman, Cardiothoracic surgeon
Next review due July 2023

A thoracic aortic aneurysm is when your aorta (the largest blood vessel in your chest), expands and bulges outwards. It’s a serious condition that needs to be monitored closely because if the aneurysm bursts, it can be fatal.

An image showing thoracic aortic aneurysm

About thoracic aortic aneurysm

Your aorta is the artery (blood vessel) that carries blood from your heart to the rest of your body. The part of your aorta that travels through your chest (thorax) is called your thoracic aorta. Where your aorta travels down into your tummy area (abdomen), it’s called your abdominal aorta. Your aorta is normally about 2 to 3 cm (about an inch) wide.

If you have a weak spot in your aorta, the blood vessel may get wider. If it grows to 1.5 times its normal size, this is called an aortic aneurysm. If this aneurysm is in your chest, it’s called a thoracic aortic aneurysm. If it’s in your tummy area, it’s called an abdominal aortic aneurysm. You can have more than one aneurysm at the same time. About four in 100 people over 65 have a thoracic aortic aneurysm. Your risk of getting one increases as you get older. Thoracic aortic aneurysms are more common in men than in women.

Symptoms of thoracic aortic aneurysm

You’re unlikely to have any symptoms of a thoracic aortic aneurysm unless it bursts open (ruptures) or the aorta lining tears. But if an aneurysm keeps getting bigger and pushes on surrounding tissue or nerves in your chest, you may notice:

  • chest pain or pain in your neck, back or the top of your stomach
  • difficulty breathing or shortness of breath
  • coughing
  • wheezing
  • hoarseness
  • difficulty swallowing

If one of the layers of your aorta wall tears or bursts, you may get sudden, very bad sharp pain in your chest or back. Some people say this feels like they're having a heart attack.

If the pain in your chest is really bad, and you have any of these other symptoms, contact a doctor straightaway. If the aneurysm does rupture, it may cause very bad internal bleeding and you may become unconscious. This could be fatal if you don’t have emergency surgery to repair it.

Diagnosis of thoracic aortic aneurysm

Most thoracic aortic aneurysms don’t cause any symptoms. They’re usually discovered when you’re having tests for chest pain or other symptoms that could be caused by something else.

Your GP or hospital doctor will examine you and ask you about your medical history. A chest X-ray may show that your aorta is wider than usual, but it’s not usually clear enough to show specific details. If your doctor thinks you have a thoracic aortic aneurysm, they’ll also do some other tests. These may include the following.

  • Blood tests. These will help to see how well your heart, lungs and kidneys are working and if you have any infections or inflammation.
  • A CT scan or MRI scan. These will show pictures of your thoracic aorta. They’re very useful for finding exactly where the aneurysm is.
  • A transthoracic echocardiography test. An ultrasound sensor is placed over your chest. This can show pictures of your heart and thoracic aorta.
  • A transoesophageal echocardiography test. This involves passing a small ultrasound sensor into your oesophagus or gullet (the pipe that goes from your mouth to your stomach). This can also show pictures of your heart and thoracic aorta.

Treatment of thoracic aortic aneurysm

Your treatment for a thoracic aortic aneurysm will depend on your symptoms and the size of your aneurysm. It will also depend on whether or not you have any other medical conditions or a family history of aneurysms.

Watchful waiting

If your aneurysm is small (less than 5.5 cm), you may not need to have any treatment. But this depends on whether or not you have any symptoms and what’s caused the aneurysm. You’ll need regular scans, usually every six months, to see if your aneurysm gets any bigger. Aneurysms usually grow slowly so if your doctor keeps an eye on your aneurysm, you can get treatment before it’s likely to rupture.


  • If you’re being monitored, changing your lifestyle may help to keep your heart and arteries healthy and stop your aneurysm getting bigger. Get help for any medical condition that may be causing your aneurysm, such as high blood pressure.
  • If you smoke, try to quit.
  • Take steps to lower your cholesterol.
  • Maintain a healthy weight by eating a balanced diet and doing gentle exercise.


Your doctor will suggest you have aortic aneurysm surgery if your aneurysm is:

  • larger than 5.5cm
  • expanding quickly
  • causing pain or other symptoms, such as difficulty breathing

They'll also suggest surgery if:

  • you have a family history of aneurysms
  • you have Marfan syndrome and your aneurysm is 5 cm or bigger – for more information on this, see our FAQ: What is Marfan syndrome? below
  • you have Marfan syndrome and other things that make your aneurysm more likely to burst – you may need to have surgery when your aneurysm is smaller
  • you have a condition called bicuspid aortic valve, which affects the heart valve connected to your aorta – you may need to have surgery before your aneurysm gets to 5.5 cm

You'll need to have emergency surgery if your aneurysm ruptures or leaks.

There are two main types of operation for a thoracic aortic aneurysm: open surgery and keyhole surgery. The best type of surgery for you will depend on lots of things, including where your aneurysm is and your general health. Ask your doctor or surgeon for more information.

Open surgery

In open surgery for a thoracic aortic aneurysm, your surgeon will open your chest to reach your aorta. They’ll then replace the weak part of your aorta with a synthetic graft. Blood will flow through the graft inside your aorta instead of through the aneurysm. This will prevent the aneurysm getting any bigger.

Keyhole surgery

Keyhole surgery to treat a thoracic aortic aneurysm is called endovascular aneurysm repair (EVAR or TEVAR). Your surgeon will put a stent (small tube) into your aorta, using X-rays to guide them to the right place. In this procedure, your surgeon will feed a tube through an artery in your groin and up through your aorta to the aneurysm. The metal stent will be covered with synthetic graft material that will knit together with the wall of your aorta to repair it. Blood will then flow through the stent instead of the aneurysm.

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Causes of thoracic aortic aneurysm

You can get a thoracic aortic aneurysm if the wall of your aorta weakens. This causes your aorta to bulge outwards. Doctors don’t know exactly why this happens but think it’s probably due to a number of things. Some people with a thoracic aneurysm have atherosclerosis. This is where fatty deposits build up on the inside of your arteries and weaken the artery walls.

You're also more likely to get an aneurysm if you:

  • are involved in an accident that injures your aorta
  • are a man (they’re more common in men than in women)
  • smoke
  • have a family history of aneurysms or atherosclerosis
  • have high blood pressure
  • have high cholesterol
  • have Marfan syndrome (see our FAQ: What is Marfan syndrome? below), or another type of connective tissue disorder
  • have chronic obstructive pulmonary disease (COPD)
  • have certain infections
  • have chronic (long-lasting) kidney disease
  • have a problem with your heart valve that's connected to your aorta

Complications of thoracic aortic aneurysm

A thoracic aortic aneurysm can burst if the weak part of your aorta isn’t strong enough to withstand the pressure of the blood inside it. Aneurysms are more likely to rupture as they get bigger. If your aneurysm is more than 6 cm wide, the chances of it rupturing are much higher. This is a really serious situation – it’s usually fatal unless you get treatment in time.

There are several things you can do to prevent your thoracic aortic aneurysm from rupturing.

  • Make sure you go to check-ups to monitor your thoracic aortic aneurysm if your doctor asks you to.
  • If you smoke, get some help to quit. Your GP surgery and local pharmacy can give you information about the support and products available.
  • If you have high blood pressure, take steps to lower it. Your doctor can prescribe medicines to lower your blood pressure. Losing weight, eating less salt and exercising more regularly can also help.

There are several other complications of a thoracic aortic aneurysm.

  • Heart valve problems can lead to heart failure. If the aneurysm is near your heart, it may cause the aortic valve to leak. This can cause blood to flow back into your heart (aortic regurgitation), which can stop your heart pumping properly and cause heart failure.
  • Aortic dissection. If the inner lining of your aorta tears, blood will go into the wall of your aorta. If this happens, you may feel sudden very bad chest and back pain.

Prevention of thoracic aortic aneurysm

You may be able to reduce your risk of a thoracic aneurysm by reducing your chances of atherosclerosis (a build-up of fats in your arteries). Changing your lifestyle may help. Changes you can make include:

It's important to have regular medical check-ups if you have a family history of arterial or heart disease.

Frequently asked questions

  • You may be able to drive if you have an aortic aneurysm, but this will depend on how big your aneurysm is. It will also depend on the type of vehicle you drive.

    You must contact the DVLA (Driver and Vehicle Licensing Agency) if you drive a car and your aortic aneurysm is over 6 cm in size. If you’re not sure, ask your doctor and consultant – speak to them about whether it’s safe for you to drive. It’s also worth checking with your insurer to see if they have any specific recommendations.

    If you drive a bus, coach or lorry, you must tell the DVLA if you have an aortic aneurysm of any size.

  • Marfan syndrome is a condition that affects the connective tissue in your body. People with Marfan syndrome have a defect in a gene that controls the production of elastic fibres in their connective tissue. The elastic fibres hold your joints and organs in place and help to control how your body grows. Marfan syndrome can involve lots of parts of your body, including your heart, lungs, skeleton, skin and eyes.

    About three in 10,000 people have Marfan syndrome. You can inherit the condition from one of your parents if they have Marfan syndrome. But not everyone who gets Marfan syndrome inherits it.

    If you have Marfan syndrome or another connective tissue disorder such as Ehlers-Danlos syndrome or Loeys-Dietz syndrome, you’re more at risk of getting an aortic aneurysm. This is because the elastic tissue of your aorta isn’t made properly. This makes your aorta weaker so it can widen more easily. You’ll probably need to take medicines, such as beta blockers, to make your heart beat more slowly and with less force. You’ll probably also need to have regular scans.

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Related information

Related information

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  • Reviewed by Michelle Harrison, Lead Editor, Bupa Health Content Team, July 2020
    Expert reviewer, Mark Yeatman, Cardiothoracic surgeon
    Next review due July 2023