Heart murmur in a child

A heart murmur is an extra sound heard when listening to the heart with a stethoscope, caused by turbulent blood flow through the heart or nearby blood vessels. Many heart murmurs in children are "innocent" (harmless) and relate to normal blood flow patterns rather than any structural heart problem. A smaller proportion relate to an underlying structural heart condition needing further assessment.

Innocent murmurs are common in childhood and relate to normal variations in blood flow, often becoming more noticeable during fever, exercise, or anxiety when the heart is beating faster. Murmurs caused by structural heart conditions, such as a hole in the heart or a valve abnormality, are less common but need to be identified through proper assessment. A doctor listening carefully to the specific characteristics of the murmur, alongside the child’s overall health, helps distinguish between these possibilities.

Signs suggesting the need for further assessment include a murmur associated with poor growth, breathlessness, blue-tinged lips or skin, fatigue with feeding or exercise, or a murmur that is unusually loud or has certain specific characteristics on examination. Innocent murmurs, by contrast, typically occur in a well child with normal growth and no other symptoms. A paediatrician or paediatric cardiologist can assess these features to guide whether further testing, such as an echocardiogram, is needed.

Most heart murmurs in children are innocent and not dangerous, resolving on their own or persisting harmlessly without ever causing problems. A minority relate to structural heart conditions that, once identified, can usually be well managed with monitoring or, if needed, treatment. Getting an accurate assessment gives reassurance in the many cases where the murmur is innocent, and ensures prompt appropriate care in the few where it is not.

Assessment typically starts with a thorough clinical examination, including listening carefully to the specific characteristics and location of the murmur, alongside checking growth and general health. If any features suggest a possible structural cause, an echocardiogram (heart ultrasound) is used to look directly at the heart’s structure and function. This assessment is usually straightforward and well tolerated by children.

No, innocent murmurs do not need any specific treatment, since they reflect normal blood flow patterns rather than an underlying problem. Many children’s innocent murmurs become less noticeable or disappear as they grow older. Regular follow-up is not typically needed once a murmur has been confirmed as innocent by appropriate assessment.

An innocent murmur typically occurs in a well child with normal growth, is often softer and varies with position or breathing, and is not associated with other symptoms. A pathological murmur, related to an underlying structural heart problem, may be louder, have specific characteristics on examination, and can be associated with symptoms such as poor growth, breathlessness, or bluish skin colour. A paediatrician or paediatric cardiologist’s careful examination, sometimes supported by an echocardiogram, distinguishes reliably between the two.

If a murmur is picked up during a routine examination without other symptoms, follow-up as advised by your GP or paediatrician is usually appropriate rather than urgent action. See a doctor promptly if your child has a murmur alongside poor growth, breathlessness, fatigue, or bluish discolouration of the lips or skin. A private paediatric cardiology assessment, including an echocardiogram if needed, can typically be arranged within about one to two weeks for reassurance or further evaluation.