Heart murmurs in children

The “lub-dub” sound you hear in a normal heartbeat are called the ‘heart sounds’ which comes from the valves closing as the heart squeezes to push blood throughout the body. Another sound a doctor might hear is a heart murmur– a soft whooshing or swishing that occurs between the heart sounds. A murmur can be a normal or abnormal sound and your child’s primary care doctor will regularly check for heart murmurs by listening with their stethoscope. If there is a concern, they might ask that your visit with a heart specialist like the pediatric cardiologists at CHoR.

Causes of a heart murmur

Most heart murmurs are what doctors refer to as “innocent heart murmurs”, meaning that the heart formed normally and is working just fine but there happens to be an audible extra sound (that we still call a murmur) or better termed a ‘vibration’ that can be heard as the heart is doing its normal work. These innocent heart murmurs can be intermittently audible to doctors throughout childhood and are often become easier to hear in situations where blood is circulating more vigorously such as fever, anemia, exercise and growth spurts. These types of murmurs are by far the most common.

In cases where children are born with a very abnormal heart, there usually will be a heart murmur that suggests the heart problem. These murmurs generally are much louder and are usually very obvious soon after birth or often can be diagnosed before birth by our fetal cardiology team.  Many of these major abnormalities of the heart would require some sort of intervention early in life.

The most common abnormalities of the heart that might be found later in life include small holes in the heart or minor heart valve problems.  These are quite rare and most of these types of abnormalities still would not usually need an intervention or surgery as children can ‘grow out’ of these minor differences in heart formation.

Diagnosing heart murmurs

To determine which type of heart murmur your child has, a heart specialist, or pediatric cardiologist, performs a full exam and may order tests to help diagnose the specific cause of the murmur. These tests may include:

• An electrocardiogram which assesses the heart’s electrical activity
• An echocardiogram which uses sound waves to create an image of the heart structure
• A chest x-ray to get a picture of the heart and surrounding organs

Learn more about our non-invasive testing and cardiac imaging.

How a heart murmur is treated

Heart murmur treatment depends on a number of factors, including the cause and severity of the murmur, as well as the child’s age and overall health.

In most cases, no treatment is necessary as the most common type of murmur, the ‘innocent murmur,” is just a normal sound audible when the heart beats. The pediatric cardiologist will explain this to you and your child’s doctor. These children have normal hearts and therefore can continue to be treated as normal. In general, as your child nears puberty, these innocent murmurs will no longer be audible to the practitioners who listen to your child. This type of murmur requires no regular follow up.

In the event that the murmur is a sign of a minor abnormality of the heart, your pediatric cardiologist will suggest follow up usually every 6 months or year. In rare cases, medication can help to allow time for your child to grow out of these minor abnormalities.  Almost all of these children also can continue to be treated as normal children.

In the rarest case, a catheter-based intervention or surgery might be needed to mend a hole in the heart, fix a valve or otherwise address a structural issue. Our pediatric cardiologists will work with you and your child to help understand the diagnosis, testing and treatment options that will best ensure your child can live a happy, healthy life.

Frequently asked questions about heart murmurs

Dr. Scott Gullquist answers some of the most common questions parents and guardians have.

Can you diagnose a heart murmur during pregnancy?

Our fetal cardiology team cares for mothers with high-risk pregnancies to help make an early diagnosis of heart defects. Through non-invasive testing, we can detect any abnormal heart defects and develop a care plan for the delivery and care for your newborn.

Will an innocent murmur cause any problems for my child growing up?

Your child should be able to eat and play normally with an innocent heart murmur. In fact, regular exercise and a healthy diet will help them continue to have a healthy heart as they grow older.

How common are innocent heart murmurs?

Innocent heart murmurs are very common. Can we have a statistic here about how many children have innocent heart murmurs? (we can break it up into newborns/infants if that makes more sense)

If my child’s heart murmur isn’t innocent, does that mean they’ll need surgery?

The exact treatment depends on the cause and severity of the heart murmur. In some cases, medications can help, while other cases might call for surgery. We will help determine what will work best once we are able to see your child and test accordingly.