Causes of heart murmur in children

Blood flowing through the heart usually makes a lub-dub noise. A heart murmur is an extra noise in the heart – a whoosh, swish or hum. It happens when the blood isn’t flowing smoothly through the heart.

Some heart murmurs are innocent heart murmurs. This means there’s nothing wrong with your child’s heart, and the murmur usually goes away with time. Innocent heart murmurs can happen when your child has a fever.

It’s thought that at least half of all children have innocent heart murmurs. They’re the most common kind of heart murmurs in children and teenagers.

Abnormal heart murmurs are from heart disease or other heart problems like faulty heart valves or a hole in the heart wall. These problems can be either present from birth or happen later in life.

Symptoms of heart murmur in children

If your child has an innocent heart murmur, she’ll have absolutely no symptoms of heart disease.

If your child has an abnormal heart murmur, he’ll usually have symptoms related to heart disease. These might include breathlessness and blueness of the lips, fingers and toes. If the murmur is present from birth, these symptoms might appear immediately or soon after the birth.

You can’t hear a heart murmur without a doctor’s stethoscope.

When to see a doctor about heart murmur symptoms

Any problems with a baby’s heart are likely to be picked up at birth, when the midwife or paediatrician checks over your newborn. If problems aren’t spotted then, they’ll probably be picked up in checks during your baby’s first few weeks.

If you have any concerns about your child’s breathing or colour, you should see your doctor as soon as possible.

Tests for heart murmur

If your doctor has any concerns about your child’s heart murmur, the doctor might order an ECG and a chest X-ray.

The doctor might also refer your child to a paediatric cardiologist, who might do an echocardiogram.

Heart murmur treatment

An innocent heart murmur doesn’t need any treatment, because there’s nothing wrong with your child’s heart. It’ll probably sort itself out in time.

If your child has heart disease, she’ll probably need some form of treatment. This can range from medication to surgery, depending on what kind of disease it is and how bad it is.

If your child has heart disease, it might help you to know that there are specialists who are highly trained in looking after heart problems in children and teenagers. Your child will probably have many options, and your GP can give you more information about them.