Cardiomyopathies in Children

Also known as: Arrhythmogenic Right Ventricular Cardiomyopath; Dilated Cardiomyopathy; Hypertrophic Cardiomyopathy; Restrictive Cardiomyopathy


Cardiomyopathy is a weakening of the heart muscle or a change in heart muscle structure. It is often associated with inadequate heart pumping or other heart function problems. There are several different types of cardiomyopathy:

  • hypertrophic cardiomyopathy (HCM) − the heart muscle is thicker and does not fill normally
  • dilated cardiomyopathy (DCM) − the heart is dilated and does not pump normally
  • arrhythmogenic cardiomyopathy (AC) − the connections between heart muscle cells are damaged and this can cause muscle cell death and heart rhythm problems
  • restrictive cardiomyopathy (RCM) − the heart muscle is stiff and its ability to relax and refill with blood between beats is reduced.


Last updated March 2014 by Professor WJ McKenna, Director, Inherited Cardiovascular Disease Unit, The Heart Hospital, London, UK.

What are the symptoms?

Symptoms of cardiomyopathy can include:

  • loss of consciousness
  • chest pain
  • shortness of breath
  • palpitations (being consciously aware of an abnormality in heartbeat).

Cardiomyopathy may cause heart failure and can cause sudden death.

What are the causes?

Cardiomyopathy can occur because of a genetic mutation which is passed on from generation to generation within families. HCM, DCM and AC all run in families.

DCM in children can be triggered by a viral infection.

How is it diagnosed?

Diagnosis occurs when a child shows various features of the condition. A number of tests can be used to assess the heart’s function including:

  • electrocardiogram (ECG) − this assesses the heart’s electrical activity
  • echocardiogram − this is an ultrasound scan that gives detailed pictures of the heart
  • exercise test − this looks at the heart’s performance when a person is exercising
  • cardiac magnetic resonance imaging (MRI) or cardiac computed tomography (CT) scans are forms of imaging that take detailed pictures of the heart
  • ambulatory ECG monitoring (Holter) is used to record a child’s heartbeat over one or two days during normal daily activity. The tape is then analysed on a computer and compared to any symptoms the child had.

How is it treated?

Children will cardiomyopathy will need to stay under the care of a cardiologist. In HCM, when the thickened muscle obstructs blood flow out of the heart and causes symptoms (i.e. HCM with obstruction), children may need open-heart surgery.

In DCM, drugs are used to control symptoms and prevent/delay progression in children and adolescents.

Typical drug treatments include:

  • ACE inhibitors (eg captopril, enalapril, lisinopril) − these drugs widen the blood vessels
  • betablockers (eg atenolol, bisoprolol, carvedilol) − when the heart is not working well, the body produces adrenaline, betablockers block or reduce the effects of adrenaline
  • calcium channel blockers (eg verapamil or diltiazem) − these drugs improve the heart’s ability to relax and reduce the heart rate
  • diuretics (eg frusemide) − these drugs help the body get rid of any extra fluid caused by the heart’s pumping problems
  • warfarin or aspirin − these are prescribed when the heart is not pumping properly to reduce the chances of a stroke.

Inheritance patterns and prenatal diagnosis

Inheritance patterns
DCM, HCM and ARVC are inherited in an autosomal dominant pattern.

Prenatal diagnosis
Rarely warranted.

Is there support?

Cardiomyopathy UK

Helpline: 0800 018 1024

Cardiomyopathy UK is a Registered Charity in England and Wales No. 1164263. It provides information and support to anyone affected by cardiomyopathy. The Charity runs support groups across the UK, holds information days, and produces special guides for children and young people.

Group details last updated January 2016.

Further support for young people with hypertrophic cardiomyopathy is available from Cardiac Risk in the Young (CRY) (see entry Heart Defects).

Support for bereaved families of adults who have died as a result of cardiomyopathy is provided by SADS UK (see entry Heart Defects).

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