Heart Murmurs in Newborn Babies

What is a heart murmur?

A heart murmur is an extra noise which can be heard alongside your baby’s heartbeat, when the heart is listened to with a stethoscope.

Does a heart murmur mean there is a problem?

No, not necessarily. A heart murmur can sometimes be a sign that there is a problem with the heart, like a small hole or a narrowing. However, many babies with heart murmurs have completely normal hearts. These babies have what is called an ‘innocent’ or ‘normal’ murmur.

How will I know if my baby has a heart problem?

Your baby will be seen by the paediatric staff on Kingfisher Ward approximately two weeks after birth. Many murmurs will have disappeared by this time, however, if the murmur can still be heard, your baby will most likely need to be referred to a specialist for further tests.

What should I look out for?

Most babies with heart murmurs remain well, but if your baby becomes unwell, they should be seen urgently by a doctor. Things to look out for include:

• breathing difficulties
• breathlessness or sweating when feeding
• poor feeding
• blue colour of the lips or skin
• mottled skin
• poor weight gain.

What should I do if my baby becomes unwell?

If your baby develops any of the above symptoms, please telephone your GP or out of hours service, explain your concerns and inform them that your baby has a heart murmur.

If you are seriously worried about your baby, ring 999 for an ambulance straight away.

Useful numbers

NHS 111
Dorchester Maternity Unit: 01305 254245

About this leaflet

Author: Dr Abby Deketelaere, Paediatric Consultant
Written: January 2015
Updated by: Kate Hopkins, Advanced Neonatal Nurse Practitioner, March 2023
Approved: March 2023
Review Date: March 2026
Edition: v3

If you have feedback regarding the accuracy of the information contained in this leaflet, or if you would like a list of references used to develop this leaflet, please email patientinformation.leaflets@dchft.nhs.uk