Houston Methodist. Leading Medicine.
Houston Methodist. Leading Medicine

Methodist DeBakey Cardiology Associates

Hypertrophic Cardiomyopathy (HCM)

» What is hypertrophic cardiomyopathy (HCM)?
» What causes hypertrophic cardiomyopathy?
» What are the symptoms of hypertrophic cardiomyopathy?
» How is hypertrophic cardiomyopathy diagnosed?
» How is hypertrophic cardiomyopathy treated?

What is hypertrophic cardiomyopathy (HCM)?

Hypertrophic cardiomyopathy (HCM) is a condition in which the heart's muscle fibers become "tangled." This causes the heart wall to become abnormally thick (hypertrophied) and makes it more difficult for the heart to pump blood.

Normal heart fibers
Normal heart fibers
HCM heart fibers
HCM heart fibers

HCM is usually asymmetrical, meaning that one part of the heart is thicker than the others. The location of the thickened tissue and the extent of the thickness determine whether the condition interferes with blood flow and which, if any, symptoms or complications the condition causes.

While HCM can occur in people of all ages, severe cases are most common in younger people.

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What causes hypertrophic cardiomyopathy?

HCM is caused by a mutation in the genes that control heart muscle growth; therefore, it is usually passed down through family lines. Be sure to let your doctor know if someone in your family has been diagnosed with HCM so that he or she can monitor your condition.

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What are the symptoms of hypertrophic cardiomyopathy?

In mild cases of HCM, the patient may notice no symptoms; in other cases, symptoms may include:

  • Shortness of breath
  • Dizziness
  • Chest pain
  • Fainting, especially during physical exertion
  • Lightheadedness, especially during or after physical exertion
  • Palpitations

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How is hypertrophic cardiomyopathy diagnosed?

Your doctor may suspect HCM if he or she hears a certain type of murmur while listening to your heart. Diagnosing the condition may involve one or more tests, including:

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How is hypertrophic cardiomyopathy treated?

In most patients, HCM can be successfully treated with medications such as beta blockers, calcium channel blockers, antiarrhythmics and/or diuretics. If the condition is obstructing blood flow, your doctor may discuss more intense treatment options, including:

  • Myectomy: A surgical procedure in which the thickened portion of the heart wall is removed to restore normal blood flow.
  • Alcohol Septal Ablation (ASA): A catheter-based procedure in which alcohol is injected into the obstructive tissue to induce a small, controlled heart attack. As a result, the tissue scars and shrinks down to its normal size, relieving the obstruction.
  • Pacemaker: Studies have shown that implanting a dual-chamber pacemaker can relieve some symptoms of HCM by timing the heartbeat so that the thickened muscle does not contract until after some blood has been ejected.
  • Implantable cardioverter-defibrillator (ICD): In HCM patients who are at risk for life-threatening rhythm disturbances, an ICD can monitor the heart's rhythm and deliver an electric shock if needed to correct a dangerous irregularity.

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For more information about Methodist DeBakey Cardiology Associates or to make an appointment, please call us at 713-441-1100 or 888-361-4375, or contact us online.