The heartbeat has two distinct sounds that you can hear with a stethoscope. These two thumping sounds are the sounds of the heart valves closing. A heart murmur is heard in between these two normal valve sounds. The murmur sound is caused by blood flowing turbulently through the heart, like the sound of a stream flowing into a whitewater pool. A murmur can occur in several different parts of the heart and blood vessels even though the heart is completely normal.
Innocent murmurs occur in about half of all children at some time during childhood.
To diagnose an innocent murmur, your doctor will ask about your child's growth, and listen carefully to the heart. Your doctor may want to know if your child is able to exercise as much as other children the same age. Innocent murmurs have a very distinctive sound. Your doctor can usually tell the difference between an innocent murmur and a murmur that can cause problems. It is not necessary to have any tests done when an innocent murmur is diagnosed, unless advised by your doctor.