What it is

When cardiomyopathy occurs, the normal muscle in the heart can thicken, stiffen, thin out, or fill with substances the body produces that do not belong in the heart muscle. This reduces the heart’s ability to pump blood. Cardiomyopathy in young people can be passed down from a parent, caused by a heart problem or other disease present at birth, or result from a viral infection. Sometimes the cause is unknown.

Types of cardiomyopathy

Cardiomyopathy can occur in children regardless of age, race, and sex, and may have no early symptoms. The two most common types of cardiomyopathy in children are dilated cardiomyopathy and hypertrophic cardiomyopathy.

Dilated cardiomyopathy (DCM). An enlargement and weakening of the heart’s muscles, particularly the left ventricle (lower chamber). This weakening reduces the heart’s ability to pump blood effectively and can lead to heart failure, arrythmias, and other complications.

Hypertrophic Cardiomyopathy (HCM). A condition in which the heart muscle is thickened, which can cause sudden death in adolescents and young adult athletes. It is often an inherited condition, and a person may not have any symptoms. If there is a family history of hypertrophic cardiomyopathy, family members can be tested and adjust their activities to reduce the risk of sudden death.

Signs and symptoms

Children with cardiomyopathy may have no symptoms at first. When symptoms appear, they can include:

• A heart murmur
• Rapid breathing or shortness of breath
• Chest pain
• Trouble exercising
• Abnormal heartbeat (arrhythmias)

Often, the condition is not recognized until heart failure develops.

Diagnosis

Healthcare professionals diagnose cardiomyopathy by looking at your signs and symptoms, family history, and heart imaging tests such as echocardiography (ECG) and magnetic resonance imaging (MRI). If your provider finds that you do have cardiomyopathy, the next step is to determine the type. This will help them recommend the right treatment plan.

If you suspect cardiomyopathy, speak with a health care professional.

Treatment

Treatment of cardiomyopathy may include medications, changes to physical activity, or surgery. In many cases, early diagnosis and treatment can help children recover and stay healthy.

Decisions about exercise for children and teens with cardiomyopathy are based on individual risk, including heart function and risk of sudden cardiac death. Those at higher risk may need to avoid intense or competitive activity, while others can safely do light to moderate exercise with medical guidance. If your child has been diagnosed with cardiomyopathy, talk with their health care team about the risks of exercise.