What exactly is a heart murmur?
When a doctor places a stethoscope on your child’s chest, the familiar “lub-dub” comes mainly from the heart valves closing. Sometimes, blood moving through the heart and nearby blood vessels creates an additional whooshing or swishing sound. That extra sound is called a murmur.
Some murmurs are caused by a structural difference in the heart, such as a valve problem or an opening between heart chambers. But many are simply the sound of blood moving through a normal, healthy heart. These are called innocent murmurs, and they are remarkably common.
How common are innocent murmurs?
A murmur may be easier to hear when a child has a fever, is anxious, has just been active, or when the heart is simply beating faster. The sound can also change as a child grows. That means a pediatrician may hear a murmur at one visit even though it was not noticeable six months earlier. In fact, innocent murmurs are particularly common in school-aged children, more than two-thirds may have one.
of children will have a heart murmur heard at some point during childhood.
Beyond infancy, only about 1% of childhood murmurs are associated with structural heart disease that requires intervention.
Then why send my child to a cardiologist?
Sometimes the pediatrician is confident that a murmur is innocent and simply follows it during routine visits. Other times, the murmur sounds different enough to deserve a closer look, or there may be symptoms, a specific medical history, or a family history that makes further evaluation appropriate. A referral does not necessarily mean your child’s doctor believes something is wrong. At a pediatric cardiology visit, we ask about your child’s health, activity level, symptoms and family history, and we listen carefully to the heart. Not all murmurs sound alike, and several features help us determine what, if any, testing is needed.
Will my child need an echocardiogram?
Maybe, but not every child with a murmur needs one. An echocardiogram, or heart ultrasound, allows us to see the heart’s chambers, valves and major blood vessels. It is painless and does not use radiation. Whether a child needs one depends on the child’s age, history, exam and sometimes additional testing. Our goal is to avoid unnecessary tests while making sure we have the information we need.
So, should I worry?
Hearing the words heart murmur can sound much more serious than it usually turns out to be. Most childhood murmurs, particularly in otherwise healthy older children, are innocent. If your child’s doctor recommends a pediatric cardiology evaluation, the purpose is to understand why the murmur is there, determine whether any testing is needed, and make sure your child’s heart is healthy.
And quite often, the answer is the same as what your doctor heard: simply the normal flow of blood through a healthy heart.
