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Hypertrophic cardiomyopathy

Hypertrophic heart

Hypertrophic cardiomyopathy (HCM) is an inherited disease of your heart muscle, where the muscle wall of your heart becomes thickened.

HCM is a genetic condition caused by a change or mutation in one or more genes and is passed on through families. Each child of someone with HCM has a 50 per cent chance of inheriting the condition.

About 1 in 500 of the UK population has the condition, although most people who have it have few, if any, symptoms.

How does HCM affect my heart?

If you have HCM, the muscular wall of your heart - the myocardium - becomes thickened, making the heart muscle stiff.
This thickening makes it harder for your heart to pump blood out of your heart and around your body.
How thick your muscle is, and how much of your muscle is affected, varies from one person to another. The left ventricle (one of your heart's four chambers) is almost always affected, and in some people the muscle of the right ventricle also thickens.

What are the symptoms of HCM?

Common symptoms include:

  • Shortness of breath
  • Chest pain
  • Palpitations
  • Light headedness and fainting

You may find that you never have any serious problems related to your condition, and with treatment, your symptoms should be controlled. However some people may find that their symptoms worsen or become harder to control in later life.
The area of heart muscle that is affected by HCM and the amount of stiffening that occurs will determine how the symptoms affect you.
For some people, a number of other conditions can develop as a result of having HCM. These may include abnormal heart rhythms, or arrythmias, including heart block and endocarditis.

How is HCM diagnosed?

The most common tests for hypertrophic cardiomyopathy are:

  • ECG - this records the electrical activity of your heart.
  • Echocardiogram - this shows the pumping action of your heart.
  • Exercise test - in this test, an ECG is recorded while you’re on a treadmill or an exercise bike, to see how your heart works when it’s more active.
  • MRI scan - creates detailed images of your internal organs, such as your heart.

Genetic testing for HCM

Hypertrophic cardiomyopathy is an inherited heart condition, which means that it’s passed on through families. If your doctor thinks that you have HCM, you may be offered a genetic test to identify a faulty gene that may be causing your condition. 

If you’re found to have a faulty gene, your specialist may ask for your help in identifying close relatives – such as parents, siblings or children – who may have also inherited this gene. 

Being tested as soon as possible means that your treatment can start as quickly as possible, which will reduce your risk of developing life-threatening abnormal heart rhythms.

For information on your nearest clinic for inherited heart conditions and support about genetic testing, call the BHF Genetic Information Service on 0300 456 8383

The Miles Frost Fund

Miles Frost

Miles Frost, son of Sir David Frost, passed away age 31 after suffering a cardiac arrest caused by undiagnosed hypertrophic cardiomyopathy.

His family have joined forces with us to set up The Miles Frost Fund, to raise money for genetic testing. 

Miles' story

How is HCM treated?

At present there is no cure for HCM, but treatments are available to help control your symptoms and prevent complications. Your treatment will depend on how your heart is affected and what symptoms you have.
You may need:

  • Medicines – to help control your blood pressure, abnormal heart rhythms or other symptoms you may have
  • A pacemaker – to control your heart rate
  • An ICD – if you are at risk of having a life threatening abnormal heart rhythm.

How will HCM affect me?

Research has shown that, with proper treatment and follow-up, most people with the condition live a normal life.

However, because there is a very small risk of getting a life-threatening abnormal heart rhythm, a small number of people with HCM are at risk of sudden cardiac death. It’s important to discuss this risk with your doctor, who may offer medication or advise that you need to have an ICD fitted if you are at an increased risk.
You may have to make some small changes to your lifestyle, such as avoiding competitive sports, but you should be able to continue to work and drive a car, for example.
However, you will not be able to drive an HGV or commercial passenger vehicle and you may have to reconsider manual jobs which involve strenuous activity. 

Beat heartbreak from hypertrophic cardiomyopathy

Our research funding has already helped scientists to better understand heart conditions like hypertrophic cardiomyopathy. 

This research was only possible through generous donations from the public. Your donations help us fund hundreds of top scientists all over the UK, working on more than a thousand different research projects, but more still needs to be done. 


For more information

Call our BHF Genetic Information Service on 0300 456 8383 to speak to one of our specialist nurses for information about inherited heart conditions and how they can affect you and your family.