Heart Murmurs

What is a heart murmur?

A murmur is a sound that can be heard when a health care provider listens to the heart with a stethoscope. It is the sound of blood flowing through structures of the heart (chambers, valves and blood vessels). A heart murmur is the most common reason that children are referred to our cardiology clinic.  

There are two type of murmurs: innocent and pathologic.

Types of heart murmurs

Innocent murmurs

Innocent murmurs are very common during infancy, childhood and adolescence. Most children will have a murmur at some time in their life.

Murmurs themselves don’t cause symptoms and most disappear by adulthood. The murmur can also disappear, then come back. The murmur can also get louder when a child is ill, running a fever, exercising, anxious or fearful.

Diagnosing an innocent murmur

Your health care provider will listen to your child’s heart and examine your child. Because innocent murmurs sound different than pathologic murmurs, the provider can typically distinguish between the two just from listening to the child’s heart.

Sometimes your child’s health care provider will request an electrocardiogram (ECG) and/or an echocardiogram (sonogram) to rule out a problem with the heart.

If there are no underlying problems with the heart or the blood flow, no treatment is necessary for innocent murmurs. You will not need to follow up with the cardiology team. Your child will not need any special precautions and can continue all normal diet and activity. Your child can live a normal, active life.

Pathologic murmurs

A pathologic murmur is caused by a structural problem in the heart, such as a leaky valve, hole in the heart wall or narrowed valve or vessel. This type of murmur may cause symptoms such as fatigue, shortness of breath, or chest pressure.

Diagnosing a pathologic murmur

If your child’s health care provider thinks the murmur sounds like the blood flow is going through the heart abnormally, they will order an echocardiogram. This is a non-invasive sonogram (ultrasound) of the heart that will show the structures of the heart and how the blood is flowing. If the health care provider finds a problem, they will inform you and talk to you about treatment.