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What Is Cardiomyopathy?

Cardiomyopathy (pronounced card-ee-oh-my-OP-ah-thee) is a disease of the heart’s muscular wall, called the myocardium, or a change in the heart that causes it to lose its pumping strength.

There are three main kinds of cardiomyopathy — dilated, hypertrophic and restrictive.

  • Dilated is when the heart cavity is enlarged and stretched.
  • Hypertrophic is when the muscle of the left ventricle enlarges or thickens.
  • Restrictive is when the myocardium of the ventricles becomes very stiff so it's harder for the ventricles to fill with blood between heartbeats.

Cardiomyopathy usually starts in the walls of the ventricles. The damage hurts the heart's ability to pump blood and can lead to congestive heart failure.

Cardiomyopathy in Children

The most common kind of cardiomyopathy in children is dilated. Viral infections are a common cause. These infections can inflame the heart muscle (a condition called myocarditis) and weaken it. To try keeping up with the body’s need for blood and oxygen, the heart works harder and enlarges.

Other forms of dilated cardiomyopathy are genetic, meaning it can be inherited (passed down from parents to children in their genes) and it runs in families.

Some children are born with hypertrophic cardiomyopathy, usually because of problems with a gene. This kind of cardiomyopathy can also develop after birth because of some other health problem, like acromegaly (a hormone problem that causes excess growth).

Restrictive cardiomyopathy is the least common kind. It is rare in children, but it can occur in babies born with an unusually thick lining in their heart. It can also develop in children if another condition causes scar tissue or some other substance or kind of cell to build up in their heart muscle. One example would be a tumor that invades the heart.

Cardiomyopathy at Seattle Children’s

Our heart team has treated many children with cardiomyopathy. Our heart failure service is the only subspecialty of its kind in the Northwest. We have extensive experience with the diagnosis and the treatment these patients may require, including medicines, a pacemaker or a defibrillator.

When you come to Children's, a team of people will take care of your child. Along with your child's cardiologist, you are connected with neonatologists, pulmonologists (lung doctors), nurses, child life specialists, cardiac nutritionists, social workers, heart failure nursing coordinators, and others, if their expertise is needed. We work together to meet all of your child's health needs and help your family through this experience.

Since 1907, Children's has been treating children only. Our team members are trained in their fields and also in meeting the unique needs of children. For example, the doctors who give your child anesthesia are board certified in pediatric anesthesiology. This means they have extra years of training in how to take care of kids. Our child life specialists know how to help children understand their illnesses and treatments in ways that make sense for their age. Our expertise in pediatrics truly makes a difference for our patients and families.

Who Treats This at Seattle Children's?

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Summer 2014: Good Growing Newsletter

In This Issue

  • Understanding the Power and Influence of Role Models
  • Legal Marijuana Means Greater Poisoning Risks for Children
  • Why Choose Pediatric Emergency Care?

Download Summer 2014 (PDF)