Hypertrophic Cardiomyopathy (HCM) in Children

Hypertrophic cardiomyopathy (HCM) is one of the most common heritable cardiac condition and is the most common cause of sudden cardiac arrest in the young, affecting about 1 in 500 people.

Hypertrophic cardiomyopathy (HCM) is one of the most common heritable cardiac condition and is the most common cause of sudden cardiac arrest in the young, affecting about 1 in 500 people. Familial HCM is a heart condition characterized by thickening (hypertrophy) of the heart muscle, more specifically the ventricle. The thickened heart muscle can make it challenging to keep up with the oxygen demands of the body and of the heart muscle itself.

Symptoms & Signs

Many people with HCM have a few, if any, symptoms and can lead normal lives without significant symptoms. However, this condition can also have serious consequences. Life-threatening arrhythmias resulting in cardiac arrest can sometimes be the first symptom.

Signs and symptoms of HCM may include one or more of the following:

  • Shortness of breath, especially during exercise
  • Chest pain, especially during exercise
  • Fainting, especially during or just after exercise or exertion
  • Sensation of rapid, fluttering, or pounding heartbeats (palpitations)

Heart murmur, which a doctor might detect while listening to your heart.


Managing HCM requires lifelong visits with a cardiologist to screen for potential cardiac risks and obtain a careful family history. Routine testing can consist of echocardiograms, 12-lead ECGs, Holter monitoring, exercise stress tests, cardiac MRIs, or cardiac genetic testing.


Treatment of HCM is to relieve any symptoms and to prevent sudden death. Your treatment will depend of the severity of the disease.

Your cardiologist may prescribe medications to reduce how hard the heart muscle squeezes and to slow down the heart rate so the heart can pump better. Common drugs for treatment include beta blockers.

Implantation of an implantable cardioverter defibrillator (ICD or defibrillator) may be indicated for certain patients, especially those who have had a life-threatening arrhythmia (such as ventricular tachycardia or ventricular fibrillation) or are at risk for these arrhythmias.

In certain patients, cardiac surgery may be recommended called a septal myectomy. The goal of this surgery is to remove part of the thickened septum. This can help the heart pump better and reduce the risk of ventricular arrhythmia.

Lifestyle Changes

Activity restrictions are determined by the severity of disease and the presence or absence of an ICD. Your healthcare team will help guide you in the decision-making process.

Even if there are some restrictions, it will be important to discuss the activities that are safe and appropriate for the patient, and to focus on what can be done!

Keep Exploring

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Common Treatments
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Since other heart disorders increase the risk of developing abnormal heart rhythms, lifestyle changes often are recommended. Living a “heart healthy” lifestyle can ease the symptoms experienced with heart rhythm disorders and other heart disorders, and can be beneficial to overall patient health.
The Normal Heart
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