Heart Murmur in Babies

A heart murmur is very common and is usually harmless. It commonly occurs in children between the ages of one and five years. The pediatrician usually detects it by listening to the baby's heart.
Heart Murmur in Babies

Last update: 25 June, 2021

A heart murmur may be present in up to half of all children. Most of the time it’s a harmless issue that’ll disappear with time. Other times, it represents abnormalities in the baby’s heart. We’ll tell you everything you need to know about heart murmurs in babies.

How does the heart work?

The heart is the most important organ in the human body. Its proper functioning is essential for supplying blood and oxygen to the other organs and tissues. The heart has four chambers, which are two atria at the top and two ventricles at the bottom. Functionally, we divide the heart into the left half and the right half.

For each heartbeat, the heart realizes the following complete circuit:

  • Oxygen-depleted blood arrives in the right atrium from all over the body.
  • From the right atrium, it passes into the right ventricle through a valve. From here, the oxygen-depleted blood is sent to the lungs. To leave the heart, it must pass through another valve. In the lungs, the blood expels carbon dioxide and charges with oxygen.
  • The blood arrives at the left atrium from the heart, charged with oxygen.
  • From the left atrium, it passes into the left ventricle, again through a valve.
  • Finally, the oxygen-loaded blood is ejected from the left ventricle to the entire body.
Pediatrician listening to a baby's heart to check for a murmur.

What’s a heart murmur?

In a healthy heart, with a stethoscope, a doctor listens for two sounds with each heartbeat. The first noise corresponds to the closing of the atria and ventricles once the blood has passed into the lower half of the heart.

The second noise, on the other hand, corresponds to the closing of the valves at the exit of the ventricles when the blood is expelled from them. A heart murmur is nothing more than a blood noise heard between these two normal heart sounds.

Harmless heart murmur in babies

A heart murmur in babies is a common occurrence. Usually, during a routine examination, the pediatrician may hear a heart murmur on auscultation. This generally occurs between one and five years of age.

Most commonly, it’s a harmless murmur. Harmless murmurs aren’t caused by any malfunction or abnormality in the child’s heart. The noise is simply heard, even though the heart is completely healthy. Usually, the pediatrician will be able to determine on auscultation whether it’s harmless.

In some cases, additional tests may be necessary. An example might be an electrocardiogram, which will look at the structure and function of the heart to make sure that everything’s alright.

Harmless murmurs represent the majority of murmurs detected in childhood. Harmless murmurs may only occur at specific times, such as during a fever, or they may be present all the time. Moreover, they’ll probably disappear when the child grows without having any impact on cardiac function.

Heart murmur in babies.

Organic heart murmurs

Even if they aren’t the most frequent type, heart murmurs in babies can also appear due to a heart abnormality or pathology. These murmurs, unlike the previous ones, are permanent, they’re always heard, and won’t disappear with time. In addition, they may be accompanied by other signs and symptoms. Some of them may be growth problems or unwarranted tiredness in the child.

They may be the first sign of congenital heart diseases, such as valve or heart muscle problems. In these cases, the pediatrician will be the one to detect that something isn’t working correctly, and will refer the child to a cardiologist. The cardiologist will be in charge of performing the necessary tests and determining the exact cause of the murmur and its treatment.

What you should know about heart murmurs in babies

The most common thing is that, if the pediatrician detects a heart murmur in your baby, it’s a harmless one. We must remain calm and keep in mind that with time it’ll disappear and that it doesn’t represent any threat to our child’s health. However, if the pediatrician considers that the baby’s murmur presents any sign of alarm, he’ll refer the child to a specialist for an accurate diagnosis.

Finally, as always, it’s important to keep an eye on the health of our little ones and to keep ourselves up to date with routine check-ups with the pediatrician and the vaccination schedule. This way, we’ll ensure that, if there’s any problem, we’ll be able to make sure that the child’s health doesn’t deteriorate.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.