Hypertrophic cardiomyopathy (HCM) causes thickening of the heart muscle, particularly in the left ventricle in the lower part of the heart. This can lead to symptoms such as heart murmurs, swelling, fatigue, and chest pain.

Cardiomyopathy is an umbrella term used to describe difficulties with your heart being able to pump blood. There are different subtypes of this condition, including hypertrophic cardiomyopathy (HCM).

It’s important to talk with a doctor if you’re experiencing possible symptoms of HCM. While most people can lead everyday lives with this condition, there’s also a risk of developing heart-related complications if HCM is left untreated.

Below are 12 signs and symptoms of HCM you may consider discussing further with your doctor.

Some people in the early stages of HCM may not have symptoms. However, symptoms of HCM may develop as the condition worsens or may be mild in earlier stages.

Possible symptoms of HCM include:

  • Dizziness: Reduced blood flow or irregular heart rate from HCM may cause you to feel dizzy. This can also worsen when you stand up suddenly after resting.
  • Fainting: In some cases, dizziness from HCM can also cause you to feel faint.
  • Fatigue: HCM can make you feel more tired than usual, even after getting a good night’s sleep or taking a rest.
  • Shortness of breath: This symptom can also worsen after physical activity.
  • Chest pain: Blood flow and heart rate irregularities can make you feel pain in your chest. Pain may also be worse after you eat a large meal or exercise.
  • Edema: While also a possible sign of HCM that a doctor may detect, you may also notice swelling in your stomach or extremities as an HCM symptom.
  • Gastrointestinal problems: Symptoms such as diarrhea, vomiting, and loss of appetite may occur, especially in babies and young children.
  • Fussiness: A baby or young child with HCM may be unusually fussy and inconsolable.

When to call 911

If you’re experiencing shortness of breath for longer than a few minutes despite rest, you should call 911 for emergency medical help.

Call 911 if you experience chest pain that is severe and/or travels to your arm or jaw. These may be possible signs of a heart attack.

HCM symptoms can be divided into the following four stages:

  • Stage I: This is usually when the disease is not yet showing any noticeable symptoms, though some early signs may appear
  • Stage II: In this stage, there is a noticeable thickening of the heart muscle, which shows excessive contraction but no significant scarring. The symptoms are usually caused by blockage of the lower part of the left ventricle from displacement of the mitral valve. You might begin to experience things like problems with your heart rate and swelling.
  • Stage III: In this stage, you would develop signs of left-ventricular fibrosis or scarring, negatively affecting your heart’s ability to pump blood. Symptoms can include shortness of breath, irregular heartbeat, and nausea.
  • Stage IV: By this stage, you develop overt signs of left ventricular systolic dysfunction (LVSD). Symptoms include difficulty breathing, especially at night, swelling, weight gain, and chest pain.

A doctor may detect early signs of HCM during a physical exam, possibly even before you experience symptoms. Possible signs may include:

  • Irregular heart rate: Also called arrhythmia, your heart may beat too quickly (tachycardia) with HCM. This can also lead to atrial fibrillation, which is a heart rate that’s too fast and irregular.
  • Heart murmurs: With a stethoscope, your doctor may also detect unusual sounds that arise while your heart’s beating. Murmurs have a variety of causes, including heart muscle contractions or blood circulating through the heart.
  • Swelling: In cases where HCM has progressed to heart failure, a doctor may notice swelling in your hands, stomach, or lower extremities. This is also called edema.
  • Poor or delayed growth: A pediatrician may detect this sign in babies or young children.

HCM may develop at any age. The exact cause of HCM isn’t known, but it’s thought that a combination of stress, underlying medical conditions, and genes may contribute to its development. In fact, it’s considered the most common genetic heart condition.

You may also be at an increased risk of developing HCM if you have a first-degree relative, such as a parent or sibling, with HCM. A family history of heart failure, heart attack, or cardiac arrest may also increase your individual risk.

A prompt diagnosis and treatment plan can help prevent possible HCM complications. These include heart problems, such as arrhythmias, stroke, or heart failure. While rare, HCM may also increase the risk of life threatening cardiac arrest.

If HCM is suspected either through signs a doctor sees or symptoms you self-report, they will recommend tests that measure both your heart function and any signs of thickening in the lower chamber.

These include:

  • an echocardiogram
  • an electrocardiogram
  • stress tests
  • a chest X-ray
  • cardiac magnetic resonance imaging (MRI)
  • genetic testing

Your doctor may also recommend that you temporarily wear a device to detect heart arrhythmias. These include portable devices such as Holter or event monitors, which you wear for 24-48 hours at a time.

If you’re diagnosed with HCM, a doctor can recommend treatments to reduce any symptoms you’re experiencing, as well as to help prevent complications. These may include medications such as beta-blockers or calcium channel blockers.

In some cases, surgery may be recommended to help decrease thickened tissues in the heart muscle. This will also help increase blood flow in and out of the heart.

HCM is a type of cardiomyopathy that causes your heart to grow larger and thicker, making it difficult for the muscle to pump blood as it should. While not all cases cause noticeable symptoms, it’s important to treat HCM early on to prevent heart-related complications.

On the other hand, if you’reexperiencing possible symptoms of HCM, call your doctor right away. They can help diagnose this condition accurately and offer a comprehensive treatment plan to help you feel better.