Understanding Heart Murmurs: What Are They and Are They Dangerous?

Understanding Heart Murmurs: What Are They and Are They Dangerous?

February is American Heart Month, a time to raise awareness on heart health,for both kids and their families. This month, the Heart Institute at Johns Hopkins All Children’s Hospital shares important information about heart murmurs and what parents should know.

What are Heart Murmurs?

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.They are also called “normal” or “physiological” murmurs and refer to the normal sound of blood moving through the heart and the blood vessels.

How are heart murmurs best described to parents?

Think of them like 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 a cardiologist came to your house and put a stethoscope on the wall, they’d tell you, “Your house has a murmur!” You might reply, “But this is a normal sound, we hear it all the time.” They would likely reply, “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, 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 infancy and childhood and quite harmless. Most children are likely to have had one at some time. These 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.

For more relevant pediatric healthcare information, visit HopkinsAllChildrens.org/Newsroom. 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.

Understanding Heart Murmurs: What Are They and Are They Dangerous?About Dr. Shah: Dr. Shah specializes in pediatric cardiology in the Johns Hopkins All Children’s Heart Institute. His areas of focus include noninvasive imaging, general pediatric cardiology and quality improvement. He is Tri-Chair of the Heart Institute Patient Safety & Quality committee.
Previously he was a pediatric cardiologist with Phoenix Children’s Heart Center, where he was co-director for the Cardiac High Acuity Monitoring Program for Infants and Newborns (CHAMPION) and site leader for the National Pediatric Cardiology Quality Improvement Collaborative. Dr. Shah worked to develop and implement newborn pulse oximetry screening for critical congenital heart disease in newborns across the state and served on the Arizona Department of Health’s Newborn Screening Committee. He was also the physician volunteer for the Nick and Kelly Heart Camp.
Dr. Shah completed his pediatric cardiology fellowship at Baylor College of Medicine/Texas Children’s Hospital in Houston. He is a graduate of the University of Connecticut Schools of Medicine & Business Administration. He completed his pediatric residency at Connecticut Children’s Medical Center / University of Connecticut.

*Presented by Johns Hopkins All Children’s Hospital