HealthInfo West Coast-Te Tai Poutini
A heart murmur is a sound made by blood flowing in or near the heart. Your general practice team can hear these sounds when listening to your child’s chest with a stethoscope.
Heart murmurs can be present at birth (congenital) or develop later in life.
Most heart murmurs are innocent (harmless) and caused by blood flowing through different parts of the heart. These are common and do not need any treatment.
Sometimes a heart murmur can be a sign of a problem with the heart. In tamariki (children), this is usually a problem with the valves in the heart or structure of the heart (congenital heart disease). If a tamaiti (child) has a heart problem, they may have symptoms such as cyanosis (a bluish tint to the skin, fingernails or lips). They may have fast breathing, poor feeding and poor weight gain. They may be unable to exercise, and they may sweat excessively.
If your tamaiti has symptoms of a heart problem or if your general practice team is concerned about a heart murmur, they will arrange further tests. These will include an echocardiogram which uses ultrasound to get a picture of the heart.
If health professionals listen to children's hearts in quiet conditions, they often hear innocent murmurs. These murmurs come and go and vary with breathing, heart rate and the position of the tamaiti. Innocent murmurs are louder when the heart is beating faster than usual. This can be when your tamaiti is anxious or has a temperature.
These murmurs are caused by the sound of blood flowing through different parts of the heart. Children's hearts are smaller and beat faster than adults' hearts. So, these noises are more likely to be heard. The murmurs usually disappear later in childhood.
An experienced health professional will recognise the noise of an innocent heart murmur as being different to one caused by a heart defect. Further testing is not needed. Sometimes the health professional will ask to listen to the child's heart again when they are well or older.
HealthInfo recommends the following pages
More detailed information about heart murmurs.
Information about the symptoms and causes of innocent heart murmurs in tamariki.
Written by HealthInfo clinical advisers. Last reviewed January 2025.
Review key: HIHMC-120671