Children's Hospital Colorado

Heart Murmur

What is a heart murmur in children?

A heart murmur is a noise that can be heard while listening to the heart using a stethoscope. Sometimes the murmur is simply the sound of normal blood flow moving through a normal heart (known as an innocent murmur). Other times, a murmur may be a sign of a heart problem (called an organic murmur).

The difference between innocent and organic heart murmurs in children

Heart murmurs are very common, occurring in up to 70% of kids by the time they are school age. Most murmurs are not a cause for concern and do not affect a child's health. These are called "innocent murmurs," which are produced by a normal, healthy heart. An innocent murmur can come and go throughout childhood, and usually goes away as the child gets older. Many kids will have a heart murmur at some point during their lives.

Other heart murmurs can indicate a problem with the heart. This type of murmur is caused by problems inside the heart, such as an abnormal valve or a hole in an inner wall separating the left from the right side of the heart. These murmurs are much rarer and occur in less than 1% of the population.

If your child's doctor hears a heart murmur and suspects your child may have a heart condition, he or she will order further tests. The treatment plan your cardiologist recommends will depend on the underlying heart condition.