What is Cardiomyopathy?

Cardiomyopathy is a broad term that encompasses many different diagnoses. When broken down to its most basic form, cardiomyopathy is a long word that means “heart muscle disease.” This disease of the heart muscle makes it harder for the heart to pump blood to the rest of the body.

The three most common types of cardiomyopathies that can affect both children and adults include dilated, hypertrophic and restrictive.

  • Dilated cardiomyopathy occurs when the pumping ability of the heart declines and the heart becomes enlarged, or dilated, and can’t effectively pump blood.
  • Hypertrophic cardiomyopathy involves abnormal thickening of the heart muscle, making it harder for the heart to work. This also mostly affects the left ventricle. Some people with this type of cardiomyopathy have a family history of the disease.
  • Restrictive cardiomyopathy occurs when the heart muscle becomes stiff, so it can’t expand and fill with blood between heartbeats.

“People with cardiomyopathy have hearts that are sometimes bigger or stiffer than they should be, and this can change how the heart functions,” said Robert Whitehill, MD, pediatric cardiologist at Sibley Heart Center Cardiology. “Some hearts are of normal size, but the muscle does not work properly. If you have cardiomyopathy, your heart may not be able to pump blood to the lungs and to the rest of the body like it should.”

The causes of cardiomyopathies can be genetic, although some types can be related to an infection of the heart or because of chemotherapy in early childhood. The cause of some cardiomyopathies is unknown.

“In our arrhythmia and ACT clinics, we are able to approach these conditions from every angle,” Dr. Whitehill said. “Often cardiomyopathies are inherited and affect multiple generations of family members. Our genetic counselors do a thorough job of building a family history to get a broad sense of whether siblings or other family members also need to be tested.”

Treatments for cardiomyopathy including medications, surgically implanted devices, heart surgery or, in severe cases, a heart transplant — depend on which type of cardiomyopathy a patient has and how serious it is. The doctors at Sibley Heart Center Cardiology include the Advanced Cardiac Therapies team within the Children’s Heart Center to treat patients using innovative technologies for advanced heart failure, including medical therapies, mechanical support and heart transplantation.

The first clue that a cardiomyopathy may be present often comes from parents who notice that their child is having a hard time keeping up with peers or siblings. Kids may experience shortness of breath, syncope or fainting during activity, extreme fatigue, irregular heartbeat or legs and feet that swell as if they are filled with water. Babies with cardiomyopathy may not grow well because of difficulty feeding. Some cases may be uncovered incidentally through an abnormal EKG.

The symptoms can be very subtle, and kids are so resilient, they often just don’t know or can’t fully describe what’s going on with them,” Dr. Whitehill said.

An electrocardiogram (EKG) is an important first step in diagnosing cardiomyopathy. Depending on the type, further testing may include an echocardiogram, a stress test, wearing a heart rate monitor or a cardiac MRI to observe the structure of the heart. Some kids will need a cardiac catheterization or an electrophysiological study.

“It’s really hard to get the news that your child has cardiomyopathy, but there’s a wide continuum of the disease and many innovative treatments are available,” Dr. Whitehill said. “We’re fortunate to have a robust transplant and heart failure program, and we’re on the forefront of new medications. The most important thing is to have honest conversations with your cardiologists and continue regular and consistent follow up. The condition can worsen over time, and it can affect different family members in different ways. Our goal is to ensure that families are supported because long-term care really happens at home.”

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