Innocent Heart Murmurs
What is a Heart Murmur?
A heart murmur is an extra sound heard while listening to the heart. When the noise is caused by blood flowing through a normal heart, it is called an “innocent” murmur.
Is this common in children?
Yes. Innocent heart murmurs can be heard in 50-75% of healthy children.
What causes it?
There is not one single reason for the cause of innocent murmurs. Some heart doctors (cardiologists) feel that they may be caused by normal blood flow in large blood vessels or extra strands of muscle in the pumping chamber of the heart.
Will this murmur go away? If it doesn't, should I be worried?
Innocent murmurs may become louder when your child is sick. There may be times when your doctor cannot hear the murmur. If the murmur does not go away, there is still no reason for concern since "innocent" murmurs do not affect how well the heart works.
How can you tell which murmurs are innocent?
Your child’s cardiology provider will obtain a complete health history and medical exam. The doctor will decide if further testing is needed to make the diagnosis.
Will my child need any special restrictions or follow-up?
No. From a heart standpoint, your child can play and do normal activities without any restrictions. Your child does not need antibiotics when she/he goes to the dentist or has surgery. You will need to return to the pediatric cardiology clinic only if your doctor feels you should.
Who do I call with questions?
Your child’s doctor or our clinic staff can answer any questions. Our phone number is
The Spanish version of this Health Facts for You is #6517.
The information provided should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Any duplication or distribution of the information contained herein is strictly prohibited.
Last Updated: 01/25/2013
Copyright © 01/25/2013 University of Wisconsin Hospitals and Clinics Authority. All rights reserved. Produced by the Department of Nursing. HF#6002
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