Innocent heart murmurs are sounds made by blood circulating through the heart. The sounds result from blood traveling through the heart’s chambers and valves or through blood vessels near the heart. Innocent heart murmurs are also called “normal” or “physiological” murmurs. These terms all refer to the normal sound of blood moving through the heart and the blood vessels.
Ashish Shah, M.D., M.B.A., specializes in pediatric cardiology in the Johns Hopkins All Children’s Heart Institute. On this week’s On Call for All Kids, he gives parents important information about heart murmurs and what they should know.
How should we think about heart murmurs?
I like to think of water going through the pipes in your own home. It’s a normal sound you hear every day — someone may be taking a shower, running the dishwasher or even flushing the toilet. If I came to your house and put my stethoscope on the wall, I’d tell you — “Your house has a murmur!” You’d look at me strangely and reply, “But Dr. Shah, this is a normal sound, we hear it all the time.” And I’d say, “Exactly! Because I have a stethoscope and hear water going through your pipes with it, I call it a murmur. Similarly, when I listen to your child’s heart and hear the normal sound of blood flowing through the heart, I call it a murmur.”
There are times when normal murmurs sound louder — think of the heart as your body’s engine. Just as your car engine gets louder when you step on the gas to accelerate and climb onto the highway, similarly your heart pumps harder when you need it to — for example: to fight an infection, help with recovery from a surgery or even when you run around and play.
Are innocent heart murmurs normal?
Innocent murmurs are common in children and quite harmless. Most children are likely to have had one at some time. They are very common during infancy and childhood. Innocent murmurs don’t require medication, don’t create cardiac symptoms and don’t mean there is a heart problem or disease. They may disappear and then reappear. Most innocent murmurs disappear when a child becomes an adult, but in some adults, the murmur remains for life
How is an innocent murmur detected?
Your pediatrician can hear these murmurs by listening to your child’s heart with a stethoscope. If the doctor hears a heart murmur, they may recommend more testing such as an electrocardiogram (ECG) or echocardiogram (echo). This is to confirm the murmur is innocent. After that, there is usually no need for further heart tests.
On Call for All Kids is a series featuring Johns Hopkins All Children's Hospital experts. Visit HopkinsAllChildrens.org/Stories for the latest report. You can watch Dr. Shah discuss how to know if your child might have heart issues. You also can download our free Pocket Doc app, which features a symptom checker, parenting advice and other tools for staying in touch with us.