Cardiomyopathy is a general term for diseases of the heart muscle, where the walls of the heart chambers have become stretched, thickened or stiff. This affects the heart's ability to pump blood around the body.

Symptoms of cardiomyopathy

There may be no symptoms in the early stages of cardiomyopathy. As it gets worse symptoms can include:

  • breathlessness – this may occur after activity or at rest; it may be worse when you're lying down, and you may wake up at night needing to catch your breath
  • fatigue – you may feel tired most of the time and find exercise exhausting
  • swollen ankles and legs – this is caused by a build-up of fluid (oedema); it may be better in the morning and get worse later in the day
  • a bloated tummy
  • a persistent cough, which may be worse at night
  • a pounding, fluttering or irregular heartbeat (palpitations)
  • dizziness and fainting

When to get medical advice

See your GP if you experience persistent or gradually worsening symptoms of cardiomyopathy, see symptoms section above.

Call 999 for an ambulance or go to your nearest emergency department as soon as possible if you have sudden or very severe symptoms.

Types of cardiomyopathy

Some types of cardiomyopathy are inherited and are seen in children and younger people.

Types of cardiomyopathy include:

  • dilated cardiomyopathy
  • hypertrophic cardiomyopathy
  • restrictive cardiomyopathy
  • arrhythmogenic right ventricular cardiomyopathy

Information on each of these types of cardiomyopathy is available on the NHS Choices website  

Diagnosing cardiomyopathy

Some cases of cardiomyopathy can be diagnosed after various heart scans and tests, such as an electrocardiogram (ECG) and an echocardiogram.

Cardiomyopathy that runs in the family can be diagnosed after a genetic test. If you've been diagnosed with cardiomyopathy, you may be advised to have a genetic test to identify the mutation (faulty gene) that caused this.

Your relatives can then be tested for the same mutation and, if they have it, their condition can be monitored and managed early.

Treating cardiomyopathy

There's no cure for cardiomyopathy. But the treatments described below are usually effective at controlling symptoms and preventing complications.

Not everyone with cardiomyopathy will need treatment. Some people only have a mild form of the disease that they can control after making a few lifestyle changes.

Lifestyle changes

If the cause of your cardiomyopathy isn't genetic, it should generally help to:


Medication may be needed to control blood pressure, correct an abnormal heart rhythm, remove excess fluid or prevent blood clots. 

Read about:

Broken heart syndrome

Some people who sustain significant emotional or physical stress, such as bereavement or major surgery, go on to experience a temporary heart problem.

The heart muscle becomes suddenly weakened or "stunned", causing the left ventricle (one of the heart's main chambers) to change shape. It may be caused by a surge of hormones, particularly adrenaline, during this period of stress.

The main symptoms are chest pain and breathlessness, similar to those of a heart attack – always call 999 if you or someone else experiences these.

The condition – known medically as Takotsubo cardiomyopathy, or acute stress cardiomyopathy – is temporary and reversible. It's unusual for it to happen again.

Source: British Heart Foundation and Cardiomyopathy UK

The information on this page has been adapted from original content from the NHS website.

For further information see terms and conditions.

This page was published August 2018

This page is due for review October 2019

Health conditions A to Z

Search by health condition or symptoms

Or find conditions beginning with …

Share this page


Your comments are anonymous and can’t be responded to - if you would like a reply, use the feedback form.

Your comments
Plain text only, 750 characters maximum. Don't include personal or financial information.