Pediatric cardiomyopathy

What is pediatric cardiomyopathy?

Cardiomyopathy is a group of chronic conditions that affect the heart muscle, causing it to become unusually large, stiff or thick. Cardiomyopathy prevents the heart from contracting or relaxing as it should. This affects the heart’s ability to pump enough blood through the body. If the condition becomes severe, it can lead to heart failure or sudden cardiac death.

What are the different types of pediatric cardiomyopathy?

Cardiomyopathy has five types based on the specific damage to the heart muscle. Some children have more than one type.

1. Dilated cardiomyopathy (DCM) - the most common type of cardiomyopathy in children, preventing the heart from contracting (squeezing) effectively. DCM occurs when muscles in one or more heart chambers become enlarged (dilated) or stretched.

2. Hypertrophic cardiomyopathy (HCM) - the second most common type of cardiomyopathy in children. With HCM, heart muscle, usually in the lower left chamber (left ventricle), becomes too thick. The thickened heart muscle stiffens, making it difficult for the heart to relax and fill with blood.

3. Restrictive cardiomyopathy (RCM) - involves stiff heart muscle that doesn’t allow the heart to relax properly and fill with blood. RCM causes blood to back up into the upper heart chambers (atria), causing them to become enlarged.

4. Left ventricular non-compaction (LVNC) - causes deep grooves in the heart muscle in the left ventricle, with a spongy, loose texture of muscle fibers. LVNC can have features of DCM, HCM or both, if the heart’s contracting and relaxing functions are affected.

5. Arrhythmogenic right ventricular cardiomyopathy (ARVC) - causes heart muscle in the right ventricle to be replaced by fatty or scar tissue. ARVC can affect the heart’s ability to contract, and it can disrupt the heart’s electrical activity, leading to arrhythmias (irregular heart rhythms).

What are the signs and symptoms of pediatric cardiomyopathy?

Infants (birth to age 1)

• Quick, heavy breathing with feedings

• Poor appetite and poor weight gain

• Extreme sleepiness or inactivity

• Swollen belly, face, legs, ankles or feet

• Excessive sweating

Children and adolescents (ages 1 through 19)

• Dizziness or fainting, especially with physical activity

• Extreme fatigue

• Belly or chest pain

• Nausea and vomiting

• Reduced endurance during physical activity

• Cough or difficulty breathing

• Irregular or rapid heartbeat (arrhythmia)

• Decreased appetite

• Swollen belly, face, legs, ankles or feet

How is pediatric cardiomyopathy diagnosed?

Because cardiomyopathy symptoms can mimic those of other, less serious conditions, it’s important to see a pediatric cardiologist with experience in diagnosing the condition. At Children’s Health, our cardiomyopathy team begins with a thorough evaluation to understand what your child is experiencing before conducting cardiomyopathy tests and diagnosis.

We ask you about your child’s personal and family medical history, including whether any family members have had cardiomyopathy, heart failure or cardiac arrest. We also do a physical exam to check for possible cardiomyopathy symptoms.

We may recommend further testing to confirm a diagnosis and plan treatment.

Depending on your child’s symptoms, they may need one or more tests, such as:

• Electrocardiogram (EKG) - Used to evaluate the heart’s electrical activity and check for irregular rhythms

• Echocardiogram (heart ultrasound) - Used to examine the heart’s walls and chambers for signs of enlargement or thickening and assess the function of the heart

• Blood tests - Used to check for infections or other conditions that may be related

• Genetic testing and counseling - Used to identify possible genetic causes and assess the risk of cardiomyopathy for other family members

• Exercise stress test - Used to assess your child’s heart function

• Cardiac MRI - Used to evaluate the heart’s size, shape and structure

• Holter monitor or portable EKG - Used to continuously record the heart’s activity for several days

What causes pediatric cardiomyopathy?

• Inherited genetic mutations (changes)

• Myocarditis, inflammation in the heart muscle caused by an infection

• Certain types of chemotherapy (cancer medications)

• Other heart conditions, such as a congenital (present at birth) heart disease

• Exposure to toxins, such as alcohol, certain drugs, metals or radiation

• Genetic disorders, such as muscular dystrophy

How is pediatric cardiomyopathy treated?

Treatments vary based on the type of cardiomyopathy, its severity and the symptoms your child is experiencing. At Children’s Health, our care team tailors a cardiomyopathy treatment plan specifically to your child’s needs.

Cardiomyopathy treatment options include:

• Monitoring - In the early stages, your child might not need medications or other treatments. Instead, we may monitor them regularly to detect early signs or symptoms and decide on treatment.

• Heart medications - Several medications can help your child’s heart pump blood better and relieve symptoms. Other medications can treat related issues such as blood clots, fluid buildup, irregular heart rhythms and narrowed blood vessels.

If the cardiomyopathy worsens, your child might need more advanced therapies. Our team coordinates your child’s care with our heart surgeons, electrophysiologists and interventional cardiologists as needed.

Procedures to treat cardiomyopathy include:

• Pacemakers and implantable cardioverter-defibrillators (ICDs) - If cardiomyopathy is causing an arrhythmia in your child, our doctors can implant one of these small devices. The device sits in your child’s chest, where it sends tiny electric pulses to your child’s heart to control heart rhythm.

• Heart surgery and procedures - Our surgeons and interventional cardiologists perform open and minimally invasive procedures to remove excess heart muscle. Septal myectomy and septal ablation procedures treat children who have HCM.

• Ventricular assist devices (VADs) - For severe heart failure, our heart surgeons can implant a VAD, which is a small mechanical pump. A VAD takes over the function of pumping blood to the body. 

• Heart transplant - The most advanced procedure for heart failure, a heart transplant replaces a diseased heart with a heart from a donor.