Dilated cardiomyopathy

Microscopy in the same of a blue heart.

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:

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

How does DCM affect my heart?

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.

Dilated heart
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.

Symptoms of dilated cardiomyopathy

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

How is DCM diagnosed?

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.

Treatments for dilated cardiomyopathy

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:

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.

Living with dilated cardiomyopathy

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.

Read Simon Morgan’s story of living with dilated cardiomyopathy.

However, because there is a very small risk of getting a life-threatening abnormal heart rhythm, a small proportion of people with DCM 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 manage with your symptoms, 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.

Want to find out more?

Dilated cardiomyopathy booklet

Dilated cardiomyopathy booklet

This booklet explains how and why dilated cardiomyopathy can be passed down through a family, how it's diagnosed, and the tests and treatments you may receive for the condition.



Contact us

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.

Beat heartbreak from dilated cardiomyopathy

The research we fund has helped push the boundaries of our understanding of genetics, and given us tools to find and help people at risk of dangerous heart conditions.

Professor Stuart Cook, Professor of Clinical and Molecular Cardiology at Imperial College London says that “for about 1 in 4 patients with DCM we can find a genetic cause, but that leaves us with hundreds of thousands of people with DCM that we cannot explain". His research aims to find better ways to diagnose, treat and prevent people dying from this disease, and beat the heartbreak.