About Cardiomyopathy in Children

What is cardiomyopathy in children?

The term cardiomyopathy is used to describe a rare group of diseases that affect the muscle of the heart. The heart muscle may become thick, enlarged, thin, or stiff, and the disease can affect the upper chambers (atria), lower chambers (ventricles), or both. Cardiomyopathy interferes with the heart’s ability to pump blood properly or maintain its normal rhythm.

In children, cardiomyopathy may have no known cause (idiopathic cardiomyopathy), and it is sometimes diagnosed prenatally. The disease can be genetic, meaning that a gene mutation is passed down through families. It can also be the result of an infection (myocarditis) or rarely be caused by a more generalized disease (such as a metabolic syndrome or muscular dystrophy or a collagen vascular disease). Finally, toxic agents such as chemotherapy drugs can be another identifiable cause of cardiomyopathy in children and adolescents. 

There are four types of cardiomyopathy. Each type requires different treatment.  

• Dilated cardiomyopathy: The most common type of cardiomyopathy, which occurs when the ventricles—the main pumping chambers of the heart—become enlarged and stretched out (dilated). In the early stages the children may have no symptoms but as the disease becomes more advanced, heart failure symptoms develop. 
• Hypertrophic cardiomyopathy: A thickening of the muscle between the two ventricles and/or of one or both ventricle walls. Hypertrophic cardiomyopathy can manifest as a life-threatening abnormal heart rhythm, or can present with heart failure or chest pain.  
• Non-compaction cardiomyopathy: A form of cardiomyopathy with variable symptoms, where the heart muscle is very abnormally formed. The heart can become stretched, as in dilated cardiomyopathy, or stiff, as in hypertrophic cardiomyopathy. Children can be asymptomatic or can be diagnosed at a very young age.
• Restrictive cardiomyopathy: A rare type of cardiomyopathy that causes the heart muscle to become stiff, making it difficult for the chambers to properly fill with blood. Children with this type of cardiomyopathy may need to be evaluated for heart transplant soon after the diagnosis is made.

What are the symptoms of cardiomyopathy?

Sometimes children exhibit symptoms of cardiomyopathy at birth. Other children have no symptoms until they are older. Symptoms of cardiomyopathy in newborns include:

• Fast breathing or difficulty breathing
• Rapid heart rate
• Difficulty feeding
• Excessive sweating
• Poor weight gain
• Irritability or unresponsiveness 
• Unusual skin color

Symptoms in older children include:

• Abnormal heartbeat
• Shortness of breath when exercising or decreased exercise tolerance
• Stomach problems: recurrent vomiting, nausea, decreased appetite, inability to eat
• Chest pain
• Dizziness or fainting
• Unusual fatigue
• Heart palpitations
• Bloating, or distended belly
• Unusual skin color

How is cardiomyopathy diagnosed?

To diagnose cardiomyopathy in your child, we will most likely conduct a series of tests. These may include:

• Chest X-ray: can show enlargement of the heart.
• Electrocardiogram (ECG or EKG): records the electrical activity of the heart to detect abnormal rhythms.
• Echocardiography (echo): evaluates the structure and function of the heart with ultrasound waves.
• Magnetic resonance imaging (MRI): a non-invasive imaging tool that shows detailed images of the heart, accurately measures the dimensions of the chambers, and can reveal scarring of the heart muscle.
• Cardiac catheterization: a minimally invasive procedure in which a long, thin tube called a catheter is guided into the heart through the blood vessels from a tiny incision in the groin or neck. The catheter is used to enable a view of the heart, measure pressures of  the heart chambers and the lung vessels, and potentially obtain a biopsy (sample) of the heart tissue. A biopsy is warranted in certain situations and the tiny piece of heart muscle can then be examined in the laboratory which can aid in the diagnosis of a few specific types of cardiomyopathy.
• Radionuclide testing: uses tiny amounts of low-dose radioactive materials, called tracers, which are injected into a vein and light up under specific cameras as they travel to the heart. Cameras are able to produce pictures of the heart from the energy that is released and can look for abnormal blood flow to the heart muscle and more specific indications of how the heart performs under stress.
• Genetic testing: looks for gene mutations that are associated with cardiomyopathy. 

How is cardiomyopathy treated at Columbia?

Experts at the Program for Pediatric Cardiomyopathy, Heart Failure, and Transplantation tailor treatment to the type of cardiomyopathy and heart disease a patient suffers from and the severity of each case. When cardiomyopathy has a genetic cause, we provide care for all family members through our Pediatric Integrated Cardiogenetics Clinic.

Cardiomyopathy treatment includes medications, nutritional interventions, structured exercise rehabilitation, and pacemaker and defibrillator implantation in cases with life-threatening arrhythmias. Children with advanced stages of cardiomyopathy and heart failure undergo evaluation for heart transplantation and are listed and transplanted in a timely manner. 

Additionally, since we are engaged in research, part of our comprehensive program will be to offer your child the chance to participate in any clinical trials that are appropriate. The clinical coordinator and cardiologist will discuss these options with you. Participation in research is purely voluntary, and deciding not to participate in a study does not affect the care a child receives from our team.