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Cardiomyopathy

What Is Cardiomyopathy?

Cardiomyopathy (KAR-dee-oh-my-OP-ah-thee) is when the heart muscle becomes weak and enlarged, which makes it difficult to pump blood through the body.

Cardiomyopathy is a serious disease. There's usually no cure for the condition in children, but it can be treated. Lifestyle changes, medicines, and surgically implanted devices can help manage symptoms and sometimes stop the disease from getting worse.

In severe cases, a heart transplant may be necessary. Cardiomyopathy is the most common reason for heart transplants in children and teens. If the condition isn't treated, it can lead to a life-threatening arrhythmia (irregular heartbeat), heart valve problems, blood clots, and heart failure.

What Happens in Cardiomyopathy?

With cardiomyopathy, the heart muscle (called the myocardium) is abnormal. There are several types of cardiomyopathy — some make the heart muscle thicker and some make it thinner. As a result, the heart can't pump blood to the body normally.

Types of cardiomyopathy include:

  • dilated cardiomyopathy (the most common type in children): the heart muscle gets thinner
  • hypertrophic cardiomyopathy: the heart muscle gets thicker
  • restrictive cardiomyopathy (rare in children): the heart muscle gets stiff
  • other, much rarer kinds

All types of cardiomyopathy are the result of changes to the heart muscle. But their symptoms, treatments, and outlooks are different.

What Are the Signs & Symptoms of Cardiomyopathy?

Signs and symptoms associated with cardiomyopathy may include:

  • feeling very tired after normal activity
  • shortness of breath
  • chest pain or discomfort
  • dizziness, lightheadedness, or fainting
  • irregular heartbeat
  • swelling in the legs, ankles, and feet from fluid buildup
  • bloating

Someone with cardiomyopathy may not notice the signs early on. But as the disease gets worse, so do the symptoms.

Who Gets Cardiomyopathy?

People of all ages can have cardiomyopathy.

What Causes Cardiomyopathy?

In most cases, the cause of cardiomyopathy isn't known. This is called idiopathic cardiomyopathy. It can run in families. When someone is diagnosed with cardiomyopathy, his or her close family members may need to be tested to see if they also have it.

Possible causes of cardiomyopathy include:

  • infections
  • metabolic disorders
  • coronary artery disease
  • nutritional deficiencies
  • drug and alcohol abuse
  • exposure to toxins

How Is Cardiomyopathy Diagnosed?

Diagnosis of cardiomyopathy depends on which type a child has. Some kids develop a heart murmur. But most get medical care only after they show symptoms of heart failure, such as:

  • a fast heart rate
  • fast breathing or trouble breathing
  • swelling from fluid buildup
  • in infants, difficulty feeding and poor weight gain (also known as "failure to thrive")

How Is Cardiomyopathy Treated?

Treatment depends on the type of cardiomyopathy and how sick a child is when diagnosed. A child with cardiomyopathy who is critically ill might temporarily need a ventilator to help with breathing. Medicines are given to help the heart pump more easily. Some of these lower blood pressure and others relax the arteries in the body. Medicines also can help get rid of extra fluid in the lungs or in the body.

Cardiomyopathy can lead to heart failure if medicines don't help with symptoms. If this happens, the heart surgery team may implant a device to support the heart until it recovers or while a child waits for a heart transplant. The cardiac team will decide which type of device is best.

If medicines don't work after a long time, a heart transplant is often the best option for treating heart failure caused by a cardiomyopathy.

What Can I Expect?

Some types of cardiomyopathy in children may get better with medical treatment. Others can be managed with medicines but not cured — these kids need lifelong care by a cardiologist.

Children who get a heart transplant will need ongoing care from a specialized cardiology team. They also must take medicines to prevent rejection of the donor heart.

Date reviewed: March 2018