Heart murmurs in babies and children are very common but most of them are harmless. Unfortunately for some children they are the sign of a more serious heart condition.

Innocent heart murmurs

A heart murmur is an added noise to the normal ‘lub-dub’ sound of the heart. Most heart murmurs in babies and children are what doctors call innocent or functional. This means they are the sound of blood flowing through the heart in a normal way and not the sign of anything wrong with the heart.

Dr Shankar Sridharan, Paediatric Cardiologist, explains, “These murmurs are usually generated by the blood flowing at a speed around tight corners and bends in a relatively smaller heart. Children with innocent murmurs are perfectly healthy.”

Innocent murmurs are very common in babies and children, and often come and go throughout childhood. Most disappear by adolescence and require no treatment.

Congenital heart disease 

Some murmurs indicate a problem with the heart. About six out of every 1,000 babies born in England have congenital heart disease. Congenital simply means present at birth. These can be very mild or very serious depending on the type of defect.

If your GP is unsure whether your child’s murmur is innocent, or is displaying any of the symptoms below, they are likely to refer you to a cardiologist.

“An experienced paediatric cardiologist can usually distinguish an innocent from an abnormal murmur just by listening for specific acoustic characteristics,” says Dr Sridharan.

Signs that your child may have a more significant heart defect include:  

  • shortness of breath
  • a bluish tint to the skin, especially on the fingers, toes, and lips
  • getting tired easily
  • dizziness or fainting

Getting the most accurate diagnosis

If the murmur is abnormal, or your child has other symptoms, the cardiologist will likely run a detailed echocardiogram, or ultrasound, to assess the structure and function of your child’s heart. Depending on what your paediatric cardiologist finds, they may also run a number of other tests including a chest X-ray, MRI scan, or EKG (an electrocardiogram). Cromwell Hospital offers some of the most advanced diagnostic imaging equipment available, enabling our cardiologists to make the most accurate diagnosis.

“Having the benefit of technologies such as the new MRI scanner and digital X-ray machines at Cromwell Hospital means I’m able to do my best in diagnosing children’s heart conditions,” said Dr Sridharan. 

Dr Sridharan offers reassurance to parents whose children have been diagnosed with a heart condition: “Confirming that your child has a heart problem is upsetting for any parent, but it is important to remember that there is huge variation in the severity, impact, and management of the condition.”

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