Heart failure

Having heart failure means that for some reason your heart is not pumping blood around the body as well as it used to.

The most common reason is that your heart muscle has been damaged, for example after a heart attack. It can be very frightening to hear that you or a person close to you has heart failure.

What are the symptoms of heart failure?

The main symptoms are:

  • shortness of breath - when you are being active or at rest

  • swelling - of your feet, ankles, stomach and lower back areas

  • fatigue - feeling unusually tired or weak

Symptoms occur because the heart does not have enough strength to pump blood all the way round the body efficiently. This can cause fluid to pool in the feet and legs.  If this fluid is left unmanaged, it can build and spread to your stomach area and sit beneath your lungs. This reduces their ability to expand and makes you short of breath.

Medication and making changes to the way you live can make a real difference to these symptoms. People with heart failure experience different symptoms and everyone copes in different ways, so speak to your GP and your heart failure nurse about what is best for you.

For more information about understanding and managing the symptoms of heart failure, take a look at our advice and information on living with heart failure.

What causes heart failure?

Bronnach, Mending Broken Hearts Appeal supporter

Will I live to see my middle son go to school, or my baby learn to walk? Realistically, I don't know.

Bronnach's story can be seen as part of our Mending Broken Hearts Appeal.

There are lots of reasons why you might be diagnosed with heart failure. It can be sudden or it can happen slowly over months or even years.

The most common causes are:

Heart failure can also be caused by:

Heart health and cancer treatment cover imageIf you're having treatment for cancer and have a heart condition, or have been told that your treatment may affect your heart, you might find Heart health and cancer treatment helpful. It's a new booklet jointly produced by Macmillan Cancer Support and the British Heart Foundation and you can order free copies online from Macmillan Cancer Support.

Pulmonary hypertension

Heart failure can also be caused by pulmonary hypertension (raised blood pressure in the blood vessels that supply your lungs). This condition can damage the right side of your heart, leading to heart failure. In some cases the pulmonary hypertension itself is caused by an existing heart condition.

Find out more about pulmonary hypertension on NHS Choices.


Heart failure can also be caused by a rare group of conditions called amyloidosis. This is when abnormal proteins, called amyloid, build up in organs (such as the heart, kidneys and liver) and tissues, making it difficult for them to work properly. Without treatment, this can lead to organ failure.

If amyloidosis affects the heart it is called cardiac amyloidosis – or ‘stiff heart syndrome’. Cardiac amyloidosis tends to make the ventricles (the two lower pumping chambers of the heart) stiff, making it more difficult to pump blood around the body. This can lead to the symptoms of heart failure including shortness of breath, swollen ankles and abnormal heart rhythms. 

About 500-1000 new cases are diagnosed in the UK every year.

Download our information sheet for more detail or visit NHS choices.

How is heart failure diagnosed?

To diagnose heart failure, your doctor will ask you questions about your medical history, talk about your symptom and do a physical examination. In most cases you will also have further tests to confirm the diagnosis and guide how your symptoms are controlled. These include:

You may hear your doctor talk about the ‘ejection fraction’ of your heart. This refers to the amount of blood that is pushed out of your left ventricle every time your heart beats. It’s usually expressed as a percentage. A normal ejection fraction is around 50-65 per cent, as there is always some blood left in the heart after each heartbeat. Some people with heart failure have a normal ejection fraction, so ejection fraction is used alongside other tests to help diagnose heart failure.

After a diagnosis, your doctor may discuss your 'stage' or 'class' of heart failure. There are four classes, which are based on your symptoms and how they affect you. The higher the number of the class you are in, the more serious your heart failure has become.  It is also possible to move between stages as you may have episodes where your heart failure is worse because of other events, such as a further heart attack.

Treatments for heart failure

While there isn't a cure for heart failure at the moment, the treatments available to control symptoms are helping many people live full and active lives.

Your doctor is likely to prescribe drugs that will help control your blood pressure and help the pumping action of your heart.

They will also give you advice about making changes to your lifestyle such as cutting down on salt, which will help control your blood pressure, and stopping smoking.

A combination of medication and lifestyle changes will hopefully help you continue to do the things you enjoy, by helping you manage your symptoms and keeping your condition as stable as possible.

Some people with heart failure will benefit from a pacemaker or ICD. Your doctor will talk to you about these treatments if they are right for you.

Find out more

Leading the fight against heart failure

The BHF is the largest independent funder of cardiovascular research in the UK. Some highlights of our heart failure research include:

  • Looking at new ways to repair heart muscle that’s been damaged as a result of a heart attack in people with heart failure. This is known as regenerative medicine. It includes looking at how stem cells can become heart muscle cells to help with this repair.
  • Improving the levels of iron in the blood, which are often low in people with heart failure. Studies looking at whether long-term iron supplements may help improve shortness of breath and quality of life in people with heart failure.

Find out more about our heart failure research and our most ambitious research programme yet to progress the UK's fight against heart failure – our Mending Broken Hearts appeal.

Our life saving research is powered by your support. Every pound raised, helps make a difference to people's lives. Join our fight for every heartbeat.

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