What are heart tumors?

Heart tumors are an abnormal growth in the heart muscle or in one of the cardiac chambers. Heart tumors, also called cardiac tumors, are extremely rare in children. Most are nonmalignant (benign or not cancerous). Even if the tumor is not cancerous it is a very serious concern, because it can interfere with the heart’s function. A tumor can obstruct the heart valves, press on the veins and arteries attached to the heart, interfere with the electrical system that controls the heart’s beating, and cause other problems.

There are several different types of heart tumors in children:

Nonmalignant heart tumors

• Rhabdomyomas: These are the most common type of nonmalignant tumors. They are most often found on the lower chambers of the heart (the ventricles) and less frequently on the upper chambers (the atria). Often, more than one tumor will be present. Cardiac rhabdomyomas are more common in babies less than 1 year of age than in older children. Many of the children who develop them have an uncommon condition called tuberous sclerosis, in which additional tumors can form on the skin, brain and other organs. Fortunately, some rhabdomyomas spontaneously shrink or disappear on their own, without treatment.
• Fibroma: This type of tumor is most often found on the inner wall of the right or left lower chamber (ventricle), or in the septum, the wall between the ventricles. A fibroma may be large and bulge into the cavity of the chamber, interfering with the function of the heart valves and the flow of blood through the heart.
• Myxoma: This type of tumor is most often found in the left or right atrium (upper chamber). It is more common in teenagers and adults than in young children.
• Pericardial teratoma: This type of tumor is most often found at the base of the aorta and pulmonary artery, where these large arteries connect to the heart. The tumor can press on the arteries, restrict blood flow and cause other problems. (The pericardium is the sac that surrounds and protects the heart and the base of the aorta and pulmonary artery.)

Malignant heart tumors

• Rhabdomyosarcoma
• Fibrosarcoma

These malignant heart tumors are extremely rare.

There are other types of heart tumors. Your doctor will discuss your child’s heart condition with you in detail to explain the tumor.

Signs and symptoms of heart tumors

Symptoms of heart tumors include:

• Heart murmur: the heart sounds abnormal when a doctor listens with a stethoscope
• Arrhythmia: abnormal heart rhythms

Depending on the type of tumor, older children might also experience unexplained weight loss, joint or muscle pain, fatigue and frequent fevers. Sometimes the tumor doesn’t cause any symptoms at all.

Heart tumors can sometimes cause heart failure. Symptoms of heart failure in children include difficulty breathing, difficulty eating, excessive sweating and poor growth.

Heart tumors can also cause sudden death, even when the tumor hasn’t caused any previous symptoms.

Testing and diagnosis of heart tumors

Some heart tumors are diagnosed prenatally (before the baby is born), when a doctor sees the tumor during fetal echocardiogram. In some cases, the Fetal Heart Program can monitor baby and mother throughout the pregnancy and create a plan for labor and care after birth. Children’s Hospital has its own delivery unit, the Garbose Family Special Delivery Unit (SDU), on the same floor as the cardiac operating rooms and cardiac patient care units. Newborns can be in the care of pediatric cardiologists and specially trained cardiac nurses immediately. The Fetal Heart Program team will discuss delivery in the SDU with mother and family.

After your baby is born, diagnosis may include:

• Echocardiogram: sound waves create an image of the heart
• Electrocardiogram (ECG or EKG): a record of the electrical activity of the heart
• Chest X-ray
• Cardiac MRI: a three-dimensional image shows the heart’s abnormalities

Rarely, cardiac catheterization will be required. A thin tube is inserted into the heart through a vein or artery in the leg or through the umbilicus (“belly button”).

Treatments for heart tumors

Treatment options will vary depending on the size of the tumor, the type of tumor and to what extent it's interfering with heart function.

Surgery might be necessary for the following reasons: 

• The tumor is interfering with normal heart function
• A biopsy is necessary to remove the tumor, examine it under a microscope, and determine if the tumor is malignant or benign

When your child has surgery to remove a heart tumor, the surgeon might also need to perform other repairs. For instance, if the tumor has affected a heart valve, the surgeon would attempt to fix the valve.

Treatment options for different types of tumors:

• Rhabdomyomas: These tumors often regress or resolve (shrink or disappear without treatment). Instead of doing surgery, doctors monitor the tumor to see if it is shrinking. If the tumor is interfering with heart function, surgery might be necessary immediately.
• Myxomas and pericardial teratomas: Surgery is almost always required for these tumors. They don’t spontaneously get smaller (regress) and they can significantly interfere with heart function or cause arrhythmias (abnormal heart rhythms).
• Fibromas: These tumors rarely regress (get smaller) and will almost always require surgery. They can be difficult to remove because they tend to affect a larger portion of the heart tissue.

Sometimes the tumor will have damaged or “infiltrated” the heart to such an extent that heart transplant will be required.

If the tumor is cancerous, a surgeon will attempt to remove it. Chemotherapy and/or other therapies may be necessary.

Follow-up care for heart tumors

A child who has had a heart tumor will require lifelong care by a cardiologist, and early care by an oncologist may be necessary. Some types of tumors can recur (reappear). Problems caused by the tumor, such as arrhythmia (abnormal heart rhythm), may require additional treatment, such as medications or the placement of a pacemaker.

Your child will need to visit a pediatric cardiologist for checkups once a year or more frequently.