Atrial myxoma

What's an atrial myxoma?

An atrial myxoma is a tumour that can be found in the top chambers (atria) of the heart. A tumour is a mass of abnormal tissue that grows too large where it shouldn’t. Around three quarters of atrial myxomas occur in the left atria. They tend to grow on the wall (septum) that separates the right and left sides of the heart.

They’re benign, which means they don’t spread around the rest of the body like cancerous tumours. However, if the tumour grows too large it can affect how the heart works. This can cause abnormal heart rhythms (when your heart is beating too fast, too slow or irregularly) and problems with the pumping action of the heart muscle.

Overall, heart tumours are rare. Sometimes small pieces of the tumour can break off and enter the blood stream. If this happens, they can block an artery in another part of the body such as the brain (which could cause a stroke), or in the lungs (causing a pulmonary embolism).

• Learn more about cardiac tumours

What are the symptoms of an atrial myxoma?

Symptoms will vary depending on the size and position of the myxoma. They may include:

• a high temperature
• a cough
• breathlessness and/or difficulty breathing when lying flat
• palpitations
• chest pain or discomfort
• dizziness and fainting
• palpitations (like your heart is racing, pounding, fluttering or like you have missed heartbeats).
• weight loss
• tiredness
• a blueness to the skin, especially the fingers (Raynaud’s phenomenon)
• swelling on any part of the body.

What causes an atrial myxoma?

It’s not known what causes atrial myxoma but around 10% of them seem to be inherited (passed down through families). These are known as familial cardiac myxomas. They tend to occur in more than one part of the heart at a time, and often cause symptoms at a younger age than other myxomas.

There are some risk factors that make you more likely to get an atrial myxoma, such as:

• if your biological sex is female - atrial myxomas tend to be more common in women, and are sometimes associated with heart valve disease and the abnormal heart rhythm atrial fibrillation
• your age – between 40-60 is when atrial myxomas are most likely to occur
• family history – some atrial myxomas have been connected to Carney’s complex. This is a rare genetic condition that causes benign tumours to form in children and young adults. Worldwide, around 750 cases of people with this condition have been reported since 1985.

How's an atrial myxoma diagnosed?

If you visit your GP, your doctor will listen to your chest with a stethoscope. Atrial myxoma can cause heart murmurs, which are extra or unusual sounds your doctor might hear when listening to your chest. The sounds may change if you change position, for example if you are lying down or if your doctor asks you to sit up.

Your doctor may then do furthers tests, like:

• an ECG (electrocardiogram) – where sticky patches are attached to your arms, legs and chest. This test records the rhythm, rate and electrical activity of your heart
• chest x-ray – where you stand against a photographic plate and x-rays are taken. This test checks for anything unusual in the heart that needs investigating
• echocardiogram - an ultrasound of your heart where a probe is moved over your chest. It’s similar to what people have when they’re pregnant and builds up a picture of your heart
• you may also need to have some other types of imaging tests, such as a CT scan or MRI.

Most tests aren’t as scary, painful or complicated as they seem at first. Get prepared and feel better about the tests for atrial myxoma and other conditions on our tests page.

Surviving a cardiac tumour

Hear Julie's story about being diagnosed with atrial myxoma at 52, staying active and raising awareness of the condition.  

Hear Julie's story

How's an atrial myxoma treated?

Any symptoms you have can normally be controlled with medicines. However, most atrial myxomas need to be removed during open heart surgery. Other problems with your heart valves can be treated during the same surgery - talk to your surgeon about your options.

Once the myxoma has been removed, your symptoms should disappear. Heart surgery normally means that the myxoma won’t come back, but in a very small number of cases it can return.

What happens after surgery?

Even though the risk of your atrial myxoma returning is small, you’ll have follow-ups for the rest of your life to keep an eye on it. It’s especially important to go to follow-ups in the seven years after surgery as this is when the tumour is most likely to return by.

Atrial myxomas can return for a few reasons, like:

• if the whole tumour isn’t fully removed during surgery
• there are more tumours than first thought
• if the tumour has become malignant (cancerous).

Even though your chances of recovering after treatment are good, the whole experience of heart surgery can be a worrying and stressful thing to face. That’s why being as prepared as possible before surgery can help you relax and speed up the time it takes to recover.

Read our five top tips on getting in shape before surgery so you’re as prepared as possible.

Heart Helpline and other support

• speak to our cardiac nurses by phone, callback, email or online chat on Heart Helpline (Monday to Friday, 9am to 5pm)
• contact us to talk to our customer care advisors, find your local BHF shop and for any comments, compliments and complaints you may have
• sign up to our Heart Matters magazine for online information packed with health and lifestyle advice.