Heart Murmurs in Children

Heart murmurs in children are one of the four most common reasons for new-patient referrals to our cardiology offices. Our doctors have found that there is a lot of misinformation about what a heart murmur is and what it means for a child who has one. Here, pediatric cardiologist, Robert Campbell, MD, explains heart murmurs in children and what they may mean for patients and families.

What is a heart murmur?

In simplest terms, a heart murmur is the noise of turbulent blood flow. “Think about a mountain stream,” Dr. Campbell says. “Smooth water flow in the stream makes close to no noise, but the same water downstream over the rocks and rapids makes a lot of noise. That's because it's a turbulent area for water.” Pediatricians can hear these murmurs through the stethoscope while listening to your child's heartbeat.

Does a heart murmur mean my child has a heart problem?

A heart murmur and heart disease are not the same thing. A heart murmur is the noise of turbulent blood flow; all blood flow is turbulent inside both normal and abnormal hearts. In some thin-chested, quiet patients, the noise of normal turbulent blood flow may be heard; these are called innocent murmurs and there are several different types. On the other hand, some murmurs may be the first sign of underlying heart disease, such as a hole in the heart, blocked valve, leaky valve, heart muscle problem or blood vessel problem.

What is an innocent heart murmur?

Even normal blood flow has turbulence. When this occurs, it's referred to as an innocent murmur. “Innocent murmurs are simply the noises made as blood flows through the heart, over the valves and through the blood vessels. These heart murmurs in children are common, and they will often disappear on their own as children get older,” Dr. Campbell says.

If your child is diagnosed with an innocent heart murmur, no further testing is needed. These murmurs may come and go over time and can vary in loudness depending on the patient's position during the exam. Symptoms are not expected and activity restrictions are not required. Generally, after a pediatric cardiology evaluation and clearance, patients with innocent murmurs will be followed long-term by the pediatric care provider.

Do heart murmurs require further testing?

If your child's pediatrician hears a heart murmur, they should be able to detect the difference between an innocent and a serious murmur. “If any murmur is detected, your pediatrician should get a full medical history of your child and may want to run tests to be sure that the murmur is, in fact, innocent,” says Dr. Campbell. Once tests confirm the murmur is innocent, there's usually no need for a follow-up appointment.

If there is any concern that your child's heart murmur is serious, your pediatrician will refer you to a pediatric cardiologist.

If your pediatrician or other care provider believes that a cardiology evaluation is necessary, that provider should refer you to a pediatric cardiology office. Murmur evaluation includes a detailed family history, patient history, exam and resting electrocardiogram (ECG), generally. Further testing, such as a chest X-ray or echocardiography (heart ultrasound study,) may be ordered by the pediatric cardiologist.

What is a serious heart murmur and what does it mean for my child?

If a pediatric cardiologist confirms through testing that your child’s murmur is not innocent, then it could be caused by a heart condition.

“Not all heart murmurs are the same,” explains Dr. Campbell. “Some heart murmurs may be the first sign of underlying heart disease. Others could be caused by more minor heart conditions. Still, other heart murmurs may be caused by a heart defect.”

My child's pediatrician heard a heart murmur, now what?

If your child has a heart condition that requires further pediatric testing, it's critical that your child see a pediatric cardiologist. Pediatric cardiologists have special training and equipment to care for small and growing hearts.