Cardiomyopathy is a disease of the heart muscle. It can run in families and can affect one or several members of a family.

Some members of a family may be affected more than others and some family members may not be affected or have any symptoms at all.


There are three main types of inherited cardiomyopathy:
– Hypertrophic cardiomyopathy(HCM or HOCM)
– Dilated cardiomyopathy (DCM)
– Arrhythmogenic right ventricular cardiomyopathy (ARVC)

Another type of cardiomyopathy, Takotsubo cardiomyopathy, can be caused by extreme stress. This type is not passed on through families and very often disappears altogether in time.


The changes to your heart are different for each type of cardiomyopathy. They all affect the size and shape of your heart and can also affect the way the electrical system makes your heart beat.

You can read more about how each type of cardiomyopathy affects you and your heart on the specific pages listed on the right.


Although inherited cardiomyopathy cannot be cured, in most cases living with it will not affect your quality or length of life. There are many effective treatments that can help you control your symptoms and you may also need to make some lifestyle changes too. Your GP and cardiologist will advise what is right for you.

A small number of people with cardiomyopathy do experience significant symptoms which mean greater changes to their lives and their families. In some cases, there is a small risk of sudden arrhythmic death (SADS). 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.


Because cardiomyopathies can be inherited, you should speak to your doctor about screening for your family. It’s important that families affected by cardiomyopathy receive accurate assessment, diagnosis, treatment and support from specialists in a clinic for inherited heart conditions.

You can also find out more information about screening for you and your family from the BHF Genetic Information Service on 0300 456 8383. Lines are open from 9am to 5pm Monday to Friday (charged at a rate similar to 01 or 02 calls).


The British Heart Foundation produces a range of print and digital resources that are free for the public to access. For more information about cardiomyopathies, order or download the following resources:

Hypertrophic cardiomyopathy

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.


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.


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.


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.


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.


Dilated cardiomyopathy (DCM) is a disease of your heart muscle where it becomes stretched and thin.
This means that it’s unable to pump blood around your body efficiently.

Inherited DCM is caused by a change or mutation in one or more genes. If you have DCM, there is a 50 per cent chance that your child will inherit the condition.

Sometimes DCM is caused by other things, such as:
– Viral infections
– Uncontrolled high blood pressure
– Problems with your heart valves
– Excessive amounts of alcohol
– Pregnancy

In these situations, it is unlikely that DCM will be passed on through families.


If you have DCM, the left ventricle of your heart becomes dilated (stretched or ‘baggy’). As a result, the heart muscle becomes weak, thin or floppy and is unable to pump blood around the body efficiently.

This can lead to fluid building up in the lungs, ankles, abdomen and other organs of the body. This collection of symptoms is known as heart failure.


In most cases DCM develops slowly, so some people can have quite severe symptoms before they are diagnosed. The most common symptoms are:
– Shortness of breath
– Swelling of the ankles and abdomen
– Excessive tiredness
– Palpitations


The most common tests for cardiomyopathy are an ECG, which records the electrical activity of your heart, and an echocardiogram which shows the pumping action of your heart.

Your doctor may also arrange for you to have an exercise test, angiogram or MRI scan.


At present there is no cure for DCM, 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.

For some people, a number of other conditions can develop as a result of having DCM. These may include:
– Abnormal heart rhythms, or arrhythmias
– Blood clots
– Chest pain

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.


DCM is a common form of cardiomyopathy and research has shown that with proper treatment and follow-up, most people with the condition live a normal life.


Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare disease of the heart muscle.

ARVC is an inherited condition, which means that it’s passed on through families. It is caused by a change or mutation in one or more genes. The chances of inheriting ARVC vary, and you might inherit the mutation but not develop the condition.


The cells of the heart muscle are held together by proteins. In people with ARVC, these proteins do not develop properly and so cannot keep the heart muscle cells together. The muscle cells become detached and fatty deposits build up in an attempt to repair the damage.

ARVC usually affects the right side of your heart but it can affect both sides. The changes to the heart muscle mean the walls of the ventricle – one of four chambers in your heart – become thin and stretched. This means your heart doesn’t pump blood around your body properly.

ARVC can also cause abnormal heart rhythms, because your heart’s normal electrical impulses are disrupted as they pass through areas of damaged and scarred muscle cells. It usually takes many years for this to happen so most people are not diagnosed until later in life.

The condition is usually progressive, which means that it will get worse over time.


It can be difficult to diagnose ARVC, because the changes to the heart muscle are often very minor or build up in a ‘patchy’ pattern. Many of the changes and symptoms could also be caused by a number of other conditions, making diagnosis even more difficult.

Your doctor may suspect that you have ARVC because of your symptoms, or because of the results of a chest x-ray. Or you may be going for tests because someone else in your family has been diagnosed with the condition.

The most common tests for this cardiomyopathy are an ECG, which records the electrical activity of your heart, and an echocardiogram, which shows the pumping action of your heart.

Your doctor may also arrange for you to have an exercise test, signal averaged electrocardiogram or MRI scan.


ARVC has four phases. Not everyone will develop all of the phases or be affected in the same way. Many people with the condition never develop any serious problems.
1. Concealed phase
There are small changes in the right ventricle.
2. Overt phase
There are noticeable structural changes to your heart muscle. These changes affect the pumping action of the heart and cause abnormal heart rhythms.
3. Weakening of the right ventricle
Your right ventricle becomes stretched and its pumping action becomes weaker.
4. Weakening of the left ventricle
Your left ventricle is also affected. The pumping action of both your ventricles becomes weaker.

If you have ARVC, you may have one or more of the following symptoms:
– Palpitations
– Light-headedness
– Fainting
– Breathlessness
– Abnormal heart rhythms
– Swollen ankles or legs
– Swelling in the abdomen
– Risk of sudden death on exertion

Contact Numbers


Tel: 07813 596505 Or 01482 870577

Will offer support and advice on how to deal with anxiety and utilising Cognitive Behaviour Therapy to overcome any problems or difficulties you may have.


British Heart Foundation

NHS Choices