Dilated cardiomyopathy

What is dilated cardiomyopathy (DCM)?

Dilated cardiomyopathy (DCM) is a heart muscle disease that causes the heart’s main pumping chamber (the left ventricle) to enlarge and weaken.

DCM affects the ability of the heart to pump blood to the body and can progress to also affect the right ventricle and the atria.

DCM is relatively common, affecting up to 1 in 250 people.

What are the symptoms of dilated cardiomyopathy (DCM)?

In the early stages, people with DCM may have few or no symptoms.

As the disease progresses and heart function worsens, symptoms may appear such as:

• shortness of breath
• dizzy spells or blackouts
• heart palpitations
• fatigue
• swelling of the feet and ankles

What causes dilated cardiomyopathy (DCM)?

A person's genetic makeup plays a key role in whether or not DCM will occur.

Other potential causes may include:

• alcohol or drug (e.g. cocaine) abuse
• certain chemotherapy drugs
• pregnancy (late stages of pregnancy or shortly after childbirth)
• coronary heart disease, heart attack, or heart valve disease
• high blood pressure
• diabetes
• infections such as HIV and myocarditis
• thyroid disease
• viral hepatitis

How is dilated cardiomyopathy (DCM) diagnosed?

Your doctor will start by reviewing your medical history, including any family history of heart conditions or unexplained sudden death.

If DCM is suspected, they will run tests which may include:

• echocardiogram (echo)
• electrocardiogram (ECG)
• cardiac magnetic resonance imaging (CMR)
• chest x-ray
• blood tests
• stress test and coronary CT scan or angiography
• genetic testing
• myocardial biopsy, in rare cases

How is dilated cardiomyopathy (DCM) treated?

DCM treatment will vary depending on the cause and severity.

Treatments may include:

• treating underlying conditions such as diabetes or thyroid issues
• diuretics
• beta-blockers
• blood thinners
• antiarrhythmics
• lifestyle changes e.g. healthy diet, exercise, restricted fluid, and salt intake

How can dilated cardiomyopathy (DCM) be prevented?

For families with inherited gene changes, genetic testing can identify individuals at risk of developing DCM even before symptoms develop. This allows for regular heart checks to identify early stages of DCM and enables early treatment. This may enable the heart's function to be stabilised or even return to normal.

Having a heart-healthy lifestyle is important for everyone, but especially for people who have a genetic risk factor for DCM. Some lifestyle factors, e.g. drinking alcohol in excess, may cause heart dysfunction to come on at an earlier age and these factors need to be avoided. Whether lifestyle factors such as regular moderate exercise can delay DCM onset is not yet known.

Prompt treatment of other underlying conditions that can cause DCM may help to reduce the risk of DCM onset.

Read these incredible patient stories

True stories of people whose lives were affected by dilated cardiomyopathy.