Doctor discussing hypertrophic cardiomyopathy with a patient

What is hypertrophic cardiomyopathy?

Hypertrophic cardiomyopathy, or HCM, is a condition where the heart muscle becomes abnormally thick. As a result, the heart becomes inefficient and has to work harder to pump blood. This extra work can cause symptoms such as fatigue and shortness of breath, and potentially serious complications. Most people, though, can live normally with hypertrophic cardiomyopathy.

Types of hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy can affect the heart in several ways. In many cases, it causes thickening of the septum, a wall of tissue that divides your heart into two sides. Thickening of the septum between the ventricles (your heart’s lower chambers) can interfere with blood flow out of the heart.

Less commonly, HCM can cause thickening in other parts of the heart muscle, which can have many effects on your body. These effects include reducing the left ventricle’s ability to fill with blood and causing the mitral valve to leak.

Doctors classify hypertrophic cardiomyopathy into types based on where thickening of the tissue occurs and whether it disrupts blood flow. Types of this condition include:

  • Obstructive hypertrophic cardiomyopathy: This is the most common type. Thickening of the septum blocks or reduces blood flow into the aorta, the body’s largest artery.
  • Nonobstructive hypertrophic cardiomyopathy: The heart muscle thickens, but blood can still flow normally.
  • Apical hypertrophic cardiomyopathy: This subtype of nonobstructive hypertrophic cardiomyopathy affects the apex, or bottom, of the heart.

Hypertrophic cardiomyopathy symptoms

Hypertrophic cardiomyopathy may not cause symptoms, at least at first. Some people notice symptoms only when they’re exercising or exerting themselves. The condition is chronic, which means it gradually worsens, so you may notice symptoms that develop over time.

Hypertrophic cardiomyopathy symptoms include:

  • Arrhythmia (or fast and irregular heartbeats)
  • Chest pain
  • Dizziness
  • Fainting
  • Lightheadedness
  • Loss of energy
  • Shortness of breath
  • Swelling in your stomach, legs, ankles, feet or neck veins

When to see a doctor

See your primary care doctor if you experience symptoms of hypertrophic cardiomyopathy. If they suspect thickening of the heart muscle, they may refer you to a heart and vascular specialist.

visual of hypertrophic cardiomyopathy scans

Hypertrophic cardiomyopathy causes

In most cases, HCM develops due to genetic mutations that affect the way the heart muscle grows. A mutation in just one copy of a gene can be enough to cause thickening of the tissue.

Hypertrophic cardiomyopathy risk factors

Hypertrophic cardiomyopathy affects people of all ages and can develop at any time in life. Due to its genetic roots, the condition often runs in families, so if a parent was diagnosed with HCM, you have a higher risk of developing it. If you have a parent or sibling with the condition, you should talk to your doctor about your risk.

Aside from genetics, doctors have identified a few other risk factors for hypertrophic cardiomyopathy, such as high blood pressure.

Complications

Most people with hypertrophic cardiomyopathy don’t develop complications. In some cases, serious heart problems can occur, especially as the condition progresses. In young people and athletes, HCM is a common cause of sudden cardiac death, but this is very rare.

Complications of hypertrophic cardiomyopathy can include:

  • Atrial fibrillation: Thickening of the heart muscle can cause the atria (top chambers of the heart) to stretch, beat rapidly and irregularly and cause potentially dangerous blood clots.
  • Heart failure: As the heart thickens and stiffens, it may struggle to fill with and pump enough blood.
  • Stroke: Blood clots caused by atrial fibrillation can travel to the brain and cause a stroke.
  • Sudden cardiac death: If the heart beats too fast, it may suddenly stop, a condition called sudden cardiac arrest that can cause death.
  • Ventricular tachycardia/fibrillation: Another potentially dangerous arrhythmia, ventricular tachycardia is when your ventricles beat rapidly.

Diagnosing hypertrophic cardiomyopathy

Your doctor will ask about your personal and family medical history and your symptoms. They will also conduct a physical exam to check for signs of thickening of the heart muscle.

With hypertrophic cardiomyopathy, a heart murmur is often a telltale sign that something is wrong. Your doctor will listen to your heart and check for murmurs and possibly order tests to look for evidence of thickening, stiffness or obstruction.

  • Medical history and exam

    Your doctor will ask about any medical conditions you have, especially heart problems. They will also want to know whether you have a family history of hypertrophic cardiomyopathy or other heart conditions, such as arrhythmia, heart failure, stroke or heart attack.

    Your doctor will ask about your symptoms. Be sure to tell your doctor when the symptoms started, what they feel like, how often they occur and how they affect your ability to perform daily activities.

    Next, your doctor will examine you to check your physical condition and look for signs of hypertrophic cardiomyopathy. They will listen to your heart and lungs to detect issues, such as a heart murmur, that may indicate hypertrophic cardiomyopathy.

  • Imaging

    Common imaging to diagnose hypertrophic cardiomyopathy include:

    • Echocardiogram: This test uses ultrasound waves to create images evaluating the heart muscle, its thickness, its function and the valves.
    • Cardiac CT scan: This imaging test can create a 3D image of your heart that allows your doctor to look for narrowed arteries and better understand how well the heart is working.
    • Cardiac MRI scan: This test uses strong magnets and radio waves to produce images that can show how well the heart is working. These images allow doctors to look for problems with blood flow, left ventricular pumping and valve function.
    • Chest X-ray: A chest X-ray can show enlargement of the heart that may indicate hypertrophic cardiomyopathy.
  • Testing for HCM

    Several tests can also help your doctor diagnose hypertrophic cardiomyopathy or rule out other conditions that may be causing your symptoms. These tests include:

    • Electrocardiogram (EKG): EKGs measure electrical activity in your heart. The test can help detect arrhythmias and other problems caused by thickening of the heart muscle.
    • Echocardiogram: One of the most common tests for diagnosing hypertrophic cardiomyopathy, an echocardiogram uses sound waves to form images of the heart. This test can show thickening of the heart tissue.
    • Exercise stress test: An exercise stress test can show how efficiently your heart pumps. You’ll walk on a treadmill or ride a stationary bike while medical professionals monitor your heart rate, rhythm and electrical activity.
    • Heart monitors: These portable devices record your heart’s activity for a few days to a few weeks. The data can show whether you experienced any arrhythmias while wearing it.

Hypertrophic cardiomyopathy treatment

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Your doctor will determine how best to treat hypertrophic cardiomyopathy based on the type you have, how well your heart is working and whether you have any symptoms, among other factors. Treatment cannot cure the condition, but it can reduce symptoms and lower your risk for complications.

Your doctor will likely recommend changing your lifestyle to improve your heart health. They may prescribe medications to lower the heart rate and treat symptoms by helping your heart work better. If you have severe symptoms or lifestyle changes and medications haven’t helped, you may need surgery to address the condition and protect against complications.

Lifestyle changes

Lifestyle changes can help protect your heart and reduce the risk of heart problems that hypertrophic cardiomyopathy can cause. Your doctor may suggest the following:

  • Be moderately active: Exercise is good for your heart, but talk to your doctor about which activities are right for you, especially if you’re an athlete.
  • Maintain adequate hydration: Drinking too much fluid or not having enough fluid can cause the heart to function poorly, leading to feelings of lightheadedness or leg swelling.
  • Manage chronic health conditions: If you have heart failure, high blood pressure, sleep apnea or another long-term health problem, ensure you manage it appropriately to reduce the risk of complications.
  • See your doctor regularly: They will monitor you for new or worsening symptoms. They will also want to assess how well your treatment is working.

Medication

Several medications can help you manage symptoms and improve heart function by slowing down the heart rate, including:

  • Beta blockers: These medications can improve the heart’s pumping ability. They can also treat certain arrhythmias by slowing your heart rate.
  • Calcium channel blockers: These medications relax the heart muscle and can help your heart pump more efficiently.
  • Diuretics: These medications can reduce the strain on your heart by helping your body flush out excess fluids and potassium–but only if you have too much fluid in your body.
  • Mavacamten: This medication can reduce strain on the heart and improve its function in people with symptomatic hypertrophic cardiomyopathy. It targets myosin, a protein involved in muscle contraction. Careful monitoring of the heart’s function is required for this medication.

Heart procedures

Surgery and other procedures can treat hypertrophic cardiomyopathy that causes severe symptoms or has become very advanced. Your doctor can help you decide if surgery is right for you. If you decide to proceed, your options may include:

  • Alcohol septal ablation: This is a nonsurgical procedure in which your interventional cardiologist injects ethanol, a type of alcohol, into an artery that sends blood to a damaged area of heart muscle. The ethanol reduces the thickened tissue.
  • Implantable devices: You may need a pacemaker, an implantable cardioverter defibrillator or a cardiac resynchronization therapy device to stop arrhythmias or improve heart function.
  • Septal myectomy: A surgeon will remove a portion of the thickened septum to improve blood flow in the heart.
  • Heart transplant: If your heart is severely damaged, you may need a donor heart to replace it.

Locations to treat hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy requires lifelong monitoring and management. Our heart teams in North and Central Texas can offer the comprehensive care you need to live a full life. We can help arrange care at the location best suited to your needs.

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Global Heart Health Center

Global Heart Health Center

4716 Alliance Blvd Pavilion II, Ste 300, Plano, TX, 75093

902.3 mi Directions

Frequently asked questions

  • Can people with hypertrophic cardiomyopathy exercise?

    Yes, people with hypertrophic cardiomyopathy can exercise. Your doctor may recommend participating in light or moderate aerobic exercise instead of intense physical activity to reduce the risk of serious complications.

  • Is hypertrophic cardiomyopathy genetic?

    Yes, in most cases, hypertrophic cardiomyopathy is genetic. You may inherit a gene mutation from a parent that causes the heart muscle to thicken.

  • Who is at risk for hypertrophic cardiomyopathy?

    You have a higher risk for hypertrophic cardiomyopathy if at least one of your parents or siblings had the condition.

  • How common is hypertrophic cardiomyopathy?

    Hypertrophic cardiomyopathy is the most common genetic heart condition in the US. It affects around 1 in 500 people.

  • What should you avoid with hypertrophic cardiomyopathy?

    If you have HCM, your doctor may recommend avoiding vigorous physical activity due to the risk of sudden cardiac death. You should also avoid other heart-health risk factors, such as smoking, excessive alcohol consumption and foods high in sodium, sugar and unhealthy fats.

  • At what age does hypertrophic cardiomyopathy develop?

    Hypertrophic cardiomyopathy can develop at any age. Most people with this condition are diagnosed during mid-life.

  • Will losing weight help with hypertrophic cardiomyopathy?

    Reaching and maintaining a healthy weight benefits your heart health by allowing the heart to pump blood more easily and reducing the risk of cardiovascular problems.

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