Cardiomyopathy

What is cardiomyopathy?

Cardiomyopathy is a disease of the heart muscle that reduces the heart’s ability to pump blood effectively. Different kinds of cardiomyopathy cause the heart muscle to enlarge, thicken or become stiff. Cardiomyopathy can be due to a number of causes, including viral infections and certain medications. It can also be inherited. Often, the exact cause of the muscle disease is never found. Cardiomyopathy can lead to irregular heart rhythms or heart failure.

How does cardiomyopathy differ from other heart disorders?

Cardiomyopathy differs from many of the other disorders of the heart in several ways, including the following:

  • Cardiomyopathy can, and often does, occur in the young.
  • The condition tends to be progressive and sometimes worsens fairly quickly.
  • It may be associated with diseases involving other organs, as well as the heart.
  • Cardiomyopathy is a leading cause for heart transplants.

Why is cardiomyopathy a concern?

Cardiomyopathy prevents the heart muscle from pumping enough blood to meet the body’s needs. This is known as “heart failure.

What causes cardiomyopathy?

Viral infections that infect the heart are a major cause of cardiomyopathy. In some instances, cardiomyopathy is a result of another disease or its treatment, such as a complex congenital heart defect, nutritional deficiencies, very fast heart rhythms or certain types of chemotherapy for cancer. Sometimes, cardiomyopathy can be linked to a genetic abnormality. Other times, the cause is unknown. There are four types of cardiomyopathy that can affect both adults and children:

  • Dilated cardiomyopathy
  • Hypertrophic cardiomyopathy
  • Restrictive cardiomyopathy
  • Left ventricular noncompaction
  • Arrhythmic right ventricular dysplasia (a rare condition).

What is dilated cardiomyopathy?

Dilated cardiomyopathy is the most common form of cardiomyopathy. The heart muscle becomes enlarged and stretched (dilated). This causes the heart to become weak and pump inefficiently. Problems that may occur with dilated cardiomyopathy include the following:

  • Irregular heart rhythms (arrhythmias)
  • Risk of blood clots
  • Heart failure
  • Leaky mitral valve
  • Various infections (including viral) that lead to inflammation of the heart muscle (myocarditis) can cause this type of cardiomyopathy.

Contact with toxins or very powerful therapeutic drugs, such as certain types of chemotherapy given to fight cancer, have been known to cause dilated cardiomyopathy. Heredity can also be a factor. About 20% of people with dilated cardiomyopathy have a parent or sibling with the disease. In many cases, a specific cause for this type of the disease is never found.

Because the heart muscle is weak and unable to pump enough blood to meet the body’s demands, the body may try to preserve blood flow to essential organs such as the brain and kidneys by reducing blood flow to other areas of the body, such as the skin and muscles.

The following are the most common symptoms of dilated cardiomyopathy. However, each child may experience symptoms differently. Symptoms may include:

  • Pale or ashen skin color
  • Cool, sweaty skin
  • Rapid heart rate
  • Rapid breathing rate
  • Shortness of breath
  • Fatigue
  • Irritability
  • Chest pain
  • Poor appetite
  • Slow growth.

Specific treatment for dilated cardiomyopathy will be determined by your child’s health care provider based on:

  • Your child’s age, overall health and medical history
  • Extent of the disease
  • Your child’s tolerance for specific medications, procedures, or therapies
  • Expectations for the course of the disease
  • Your opinion or preference.

Your child’s health care provider may recommend medications to:

  • Help the heart beat more effectively
  • Decrease the workload of the heart
  • Decrease the oxygen requirements of the heart
  • Prevent blood clots from forming
  • Decrease inflammation of the heart
  • Regulate irregular heartbeat.

In some cases, dilated cardiomyopathy due to viral causes improves over time. In other cases, the condition worsens and a heart transplant may be considered. Consult your child’s health care provider for more information regarding the specific outlook for your child.

What is hypertrophic cardiomyopathy?

In hypertrophic cardiomyopathy, the muscle of the heart becomes thicker than normal, obstructing blood flow to the rest of the body.

The thickened muscle can also affect the mitral valve, which separates the left atrium and the left ventricle. The valve may become leaky, allowing some blood to move backwards from the left ventricle into the left atrium, instead of forward to the rest of the body.

Hypertrophic cardiomyopathy is often inherited. About one-half of children with the disease have a parent or sibling with varying degrees of left ventricular muscle or ventricular wall enlargement, although relatives may or may not have symptoms.

Children with hypertrophic cardiomyopathy may have symptoms that increase with exertion or symptoms may be unpredictable. This is the number one cause of sudden cardiac death in U.S. athletes.

The following are the most common symptoms of hypertrophic cardiomyopathy. However, each child may experience symptoms differently. Symptoms may include:

Specific treatment for hypertrophic cardiomyopathy will be determined by your child’s health care provider based on:

  • Your child’s age, overall health and medical history
  • Extent of the disease
  • Your child’s tolerance for specific medications, procedures, or therapies
  • Expectations for the course of the disease
  • The family’s opinion or preference.

The child’s health care provider may recommend medications to:

  • Decrease the workload of the heart
  • Decrease the oxygen requirements of the heart
  • Regulate irregular heartbeats.

Surgical treatment may include:

Consult your child’s health care provider for more information regarding the specific outlook for your child.

What is restrictive cardiomyopathy?

Restrictive cardiomyopathy, the least common type of cardiomyopathy in the U.S., occurs when the myocardium (heart muscle) of the ventricles becomes excessively stiff. When this happens, the ventricles are not able to relax and filling of the ventricles with blood between heart beats is impaired. This condition occurs rarely in children.

Restrictive cardiomyopathy usually results from an underlying condition that affects the rest of the body. However, in some cases the cause is unknown (idiopathic). Restrictive cardiomyopathy does not appear to be inherited, but some of the diseases that lead to the condition may be genetically transmitted.

Conditions that may be associated with the development of restrictive cardiomyopathy include:

  • Scleroderma (a chronic, degenerative disease that affects the joints, skin, and internal organs)
  • Amyloidosis (a rare disease which causes the buildup of amyloid, a protein and starch, in tissues and organs)
  • Sarcoidosis (a rare inflammation of the lymph nodes and other tissues throughout the body)
  • Mucopolysaccharidosis (a condition in which mucopolysaccharides, or carbohydrates that bond with water to form a thick, jelly-like substance, accumulate in body organs)
  • Cancer
  • Radiation therapy for cancer treatment has also been associated with restrictive cardiomyopathy.

The following are the most common symptoms of restrictive cardiomyopathy. However, each child may experience symptoms differently. Symptoms may include:

  • Shortness of breath on exertion
  • Chest pain
  • Weakness
  • Swelling of the extremities.

Specific treatment for restrictive cardiomyopathy will be determined by your child’s health care provider based on:

  • Your child’s age, overall health and medical history
  • Extent of the disease
  • Your child’s tolerance for specific medications, procedures, or therapies
  • Expectations for the course of the disease
  • The family’s opinion or preference.

Your child’s health care provider may recommend medications to:

  • Decrease the workload of the heart
  • Decrease the oxygen requirements of the heart
  • Prevent blood clots from forming
  • Regulate irregular heartbeats.

Surgical treatment may include:

Consult your child’s health care provider for more information regarding the specific outlook for your child.

What is left ventricular noncompaction?

In left ventricular noncompaction the left ventricle heart muscle structure is abnormal. The muscle in this condition has been described as “spongier” than normal and is characterized by deep “cracks” and thin bottom layer. This condition can be inherited, although that isn’t always the case.

The following are the most common symptoms of restrictive cardiomyopathy. However, each child may experience symptoms differently. Symptoms may include:

Specific treatment for restrictive cardiomyopathy will be determined by your child’s health care provider based on:

  • Your child’s age, overall health and medical history
  • Extent of the disease
  • Your child’s tolerance for specific medications, procedures or therapies
  • Expectations for the course of the disease
  • The family’s opinion or preference.

Your child’s health care provider may recommend medications to:

Surgical treatment may include:

Consult your child’s health care provider for more information regarding the specific outlook for your child.

What is arrhythmogenic right ventricular dysplasia (ARVD)?

ARVD is a rare type of cardiomyopathy that occurs if the muscle tissue in the right ventricle is infiltrated and replaced by fatty tissue and scar tissue. The presence of this abnormal tissue can cause life-threatening fast heart rhythms, which is why this disease is called “arrhythmogenic.” This type of cardiomyopathy usually affects adolescents and young adults and can result in sudden cardiac arrest in young athletes. Like many of the other cardiomyopathies, it is also inherited, and so family members of people with this disease should be evaluated.

Symptoms of ARVD include but are not limited to:

  • Heart palpitations and/or fainting after physical activity
  • Abnormal heart rhythms (arrhythmias)
  • Chest pain.

Specific treatment for ARVD will be determined by the patient’s health care provider based on:

  • The patient’s age, overall health and medical history
  • Extent of the disease
  • The patient’s tolerance for specific medications, procedures or therapies
  • Expectations for the course of the disease
  • The family’s opinion or preference.

Although there is no known cure for ARVD, treatment generally focuses on trying to reduce the patient’s symptoms and can include:

Consult your child’s health care provider for more information regarding the specific outlook for your child.

The Fetal Care Center of Southern California

Pediatric Spine Specialist and patient’s mom at CHOC’s Pediatric Spine Center

If an abnormality is detected before your baby is born, our team of pediatric experts at the Fetal Care Center of Southern California can confirm your baby’s diagnosis, provide extensive condition education and counseling, and begin comprehensive treatment planning for after your baby’s birth.

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Our pediatric cardiologists are available to provide consultations and second opinions to families and referring physicians.

To schedule a consultation,
Call 714-509-3939

If you are pregnant and would like a prenatal consultation, our team of fetal cardiologists are available for families and referring physicians to provide immediate consultations, second opinions and fetal echocardiograms for pregnant women. Our office is open 8 a.m. – 5 p.m. We schedule appointments within 48 hours, and offer same day appointments for urgent cases. Get more information about the CHOC fetal cardiology program.

To schedule a prenatal consultation,
Call 714-509-3960