If your child has a heart murmur, it is natural to wonder whether it will disappear as they grow. Many innocent murmurs become quieter or are no longer heard over time, while others remain audible without affecting your child’s heart, development or normal activities.
What matters most is why the murmur is present rather than whether the sound eventually disappears. The clinician will consider your child’s symptoms, examination findings and family history. If further assessment is needed, they may recommend referral to a paediatric cardiologist, an echocardiogram or other appropriate tests to assess your child’s heart and decide whether follow-up is required.
What Does It Mean When a Heart Murmur Goes Away?
When a clinician says that your child’s murmur has gone away, it usually means that the additional sound is no longer audible through a stethoscope. An innocent murmur may become quieter as your child grows or may not be heard at every appointment because heart rate, breathing, body position and examination conditions affect the sound.
If the murmur was associated with a diagnosed structural heart condition, the sound disappearing does not by itself prove that the condition has resolved. The cardiology team will rely on the diagnosis, examination and, when appropriate, an echocardiogram rather than the sound alone.
Which Heart Murmurs Are Most Likely to Disappear?
Innocent murmurs are the most likely to become quieter or stop being heard as your child grows. They are sounds produced by normal blood flow through a healthy heart and may also be described as functional, physiological or flow murmurs.
Some innocent murmurs disappear during childhood, while others remain audible into adolescence without causing problems. Once a clinician has confirmed that the murmur is innocent, it does not usually need treatment, whether the sound remains or eventually disappears.
Why Do Innocent Murmurs Change as Children Grow?
The sound of an innocent murmur may change as your child grows because their heart rate, body size, chest shape and pattern of blood flow change naturally with age. A murmur that is easy to hear in early childhood may therefore become quieter or no longer be detected during later examinations.
You may also notice that an innocent murmur comes and goes depending on your child’s breathing, body position or heart rate. There is no set age at which every innocent murmur disappears, so it is perfectly normal for some to remain audible for longer than others.
Why Can a Murmur Become Louder During Illness?
A heart murmur can sound louder when your child is unwell because a fever, crying, anxiety or physical activity makes the heart beat faster. The quicker blood flow makes an innocent murmur easier to hear, which is why it may first be noticed during an illness.
As your child recovers and their heart rate returns to normal, the murmur may become quieter or may no longer be heard. Even so, any newly detected murmur should be assessed properly, as your doctor will consider its characteristics alongside your child’s symptoms and examination findings rather than assuming it is innocent.
Can a Murmur Come and Go Between Appointments?
Yes, an innocent heart murmur can come and go between appointments, so it may be heard during one examination but not another. Changes in your child’s body position, heart rate, breathing or how calm they are can all affect how easily the murmur is heard.
Although this pattern is common with innocent murmurs, it does not automatically mean that every intermittent murmur has innocent characteristics. Your doctor will base their assessment on your child’s complete examination, symptoms and medical history rather than on whether the murmur is heard on one particular day.
Does a Murmur That Remains Always Need Treatment?
A heart murmur that continues to be heard does not always need treatment. Your doctor will base any treatment decisions on the underlying cause of the murmur rather than whether the sound is still present, and a persistent innocent murmur does not require medicine or surgery because your child’s heart is healthy.
Some structural heart differences may also cause a murmur for many years without affecting your child’s health, while others may need treatment if they interfere with normal heart function. Your doctor will use the examination, an echocardiogram and any other test results to decide what, if any, treatment is needed.
Can a Murmur Linked to a Heart Condition Disappear?
A murmur linked to a structural heart condition may become quieter or disappear if the underlying blood flow changes. For example, a murmur caused by some small ventricular septal defects may no longer be heard when the opening becomes smaller or closes.
However, the absence of a murmur does not always prove that the heart condition has resolved. Your child’s cardiologist may use an examination and echocardiogram to confirm what has changed and whether further monitoring is required.
Can a Ventricular Septal Defect Close Naturally?
A ventricular septal defect, or VSD, is an opening in the wall between the heart’s two lower pumping chambers. Many small muscular VSDs become smaller or close naturally during childhood, although the timescale varies considerably and some remain open.
A small VSD may require monitoring but no active treatment when it is not placing additional strain on the heart or lungs. The follow-up plan depends on the defect’s size and location, its relationship to nearby valves and its effect on blood flow and heart function. An echocardiogram provides more reliable information than the murmur’s loudness alone.
What Happens to Murmurs Linked to Newborn Circulation?
Some heart murmurs in newborns are temporary and occur as the baby’s circulation adapts after birth. However, every murmur should be assessed alongside your baby’s overall health to determine whether observation, further tests or specialist review is needed.
Assessment of Newborn Heart Murmurs
| Aspect | What It Means | Why It Matters | Next Step |
| Normal circulation changes | Blood flow changes naturally after birth | Temporary murmurs often disappear as circulation adapts | May require observation only after clinical assessment |
| Possible heart differences | A small opening, valve variation or blood vessel condition may cause a murmur | Some conditions need further assessment | An echocardiogram or specialist review may be recommended |
| Oxygen saturation | Measures the baby’s blood oxygen levels | Low oxygen levels may indicate an underlying heart problem | Further investigation may be required |
| Clinical examination | Includes checking pulses, breathing, feeding, colour and general wellbeing | Provides important clues about heart function | Helps determine the urgency of assessment |
| Specialist investigations | Echocardiogram and paediatric cardiology review if needed | Helps identify whether a structural heart condition is present | Guides diagnosis and treatment |
| Follow-up care | Based on examination findings and test results | Ensures any ongoing concerns are monitored | May involve observation or planned review |
Can Murmurs Caused by Valve Conditions Go Away?
A murmur caused by a heart-valve condition may remain, become louder or quieter, or change after treatment. A change in the sound does not necessarily show whether the valve condition has improved or worsened.
If your child has a diagnosed valve condition, the cardiologist will monitor the valve and the heart’s function using examinations and, when required, echocardiograms. Follow-up may still be needed even if the murmur becomes quieter or is no longer heard.
How Do Doctors Assess Whether a Murmur May Change?
Your doctor cannot always predict exactly when a murmur will become quieter or stop being heard. Instead, the assessment focuses on identifying why the murmur is present and whether it has innocent characteristics or is associated with a structural heart condition.
The doctor will ask about your child’s symptoms, growth, activity levels, medical history and family history. They will assess the murmur’s characteristics and may check your child’s pulses, blood pressure and oxygen saturation.
If a structural condition is suspected, an echocardiogram may be recommended to examine the heart’s chambers, valves, movement and blood flow. The diagnosis and test findings help the cardiologist explain the likely course and determine whether follow-up is needed.
Clinical Tip
Ask whether the murmur has been confirmed as innocent or linked to a diagnosed heart condition. Also ask whether follow-up is needed, whether the examination or any tests identified a structural heart problem, and which symptoms should prompt another assessment.
Will Your Child Need Regular Follow-Up?
A child with a confidently confirmed innocent murmur does not usually need regular paediatric cardiology follow-up and can continue routine healthcare. The sound does not need to disappear before your child can be discharged from specialist care.
If a structural heart condition has been identified, the type and timing of follow-up will depend on the diagnosis, its effect on the heart and whether it is changing. Attend planned reviews even when your child feels well, and contact the cardiology team if you are unsure about the next appointment or notice new symptoms (Norfolk and Norwich University Hospitals NHS Foundation Trust, 2024; Royal Brompton and Harefield Hospitals, no date).
Which Symptoms Should You Watch for Over Time?
An innocent murmur does not itself cause symptoms. Request medical assessment if a baby develops poor feeding, breathlessness or sweating during feeds, reduced activity or poor weight gain. Older children should be assessed for new unexplained breathlessness, reduced exercise tolerance, persistent palpitations, chest discomfort during activity or fainting.
These symptoms do not always mean your child has a heart condition, as they can have many different causes. However, if the symptoms are new, becoming more frequent or getting worse, let your doctor know that your child has previously been found to have a heart murmur and arrange an assessment without waiting for a routine follow-up appointment.
When Does Your Child Need Urgent Medical Help?
Call 999 if your child is not breathing, is unresponsive, cannot be woken within one minute after fainting, has not fully recovered, has difficulty speaking or moving, is shaking or jerking as if having a seizure, has been seriously injured, faints during exercise or while lying down, or faints with chest pain or a pounding, fluttering or irregular heartbeat.
Call 999 if your child has severe difficulty breathing or suddenly develops blue or grey lips, tongue, face or skin. On brown or black skin, this colour change may be easier to see on the lips, gums, inside the eyelids, palms of the hands or soles of the feet.
If your child is unresponsive, call 999 and check whether they are breathing normally. If they are breathing normally and you do not suspect a spinal injury, place them on their side with their head slightly tilted back to help keep their airway open, and continue checking their breathing until help arrives. If you suspect a spinal injury, avoid moving them unless the emergency call handler advises you to do so. If they are not breathing normally, start CPR straight away. The emergency call handler can provide instructions while help is on the way.
For worsening feeding difficulties, breathlessness, poor weight gain, persistent palpitations, chest discomfort or reduced exercise tolerance without emergency features, contact your GP, cardiology team or NHS 111. Tell the healthcare professional that your child has previously been found to have a murmur or diagnosed heart condition.
NHS Practice Note
Local NHS neonatal and paediatric pathways assess a newborn murmur alongside the baby’s oxygen saturation, femoral pulses, breathing, feeding, colour and general wellbeing. Abnormal oxygen levels, weak or absent pulses, feeding or breathing difficulties, or signs of heart failure or shock require urgent paediatric assessment rather than waiting to see whether the murmur disappears.
The urgency and timing of echocardiography depend on the baby’s clinical findings and the local neonatal pathway (Norfolk and Norwich University Hospitals NHS Foundation Trust, 2024; Leeds Teaching Hospitals NHS Trust, 2025).
Can Treatment Make a Murmur Quieter or Disappear?
A catheter procedure or heart operation may make a murmur quieter or cause it to become no longer audible by correcting the abnormal blood flow that produced the sound. However, the effect on the murmur depends on the underlying condition and the treatment performed.
Medicine is generally used to manage symptoms or reduce the workload on the heart rather than specifically to make a murmur disappear. Some structural differences require observation only. Even when the murmur is no longer heard after treatment, follow-up may remain necessary to monitor the heart, valves or repaired area.
Can Your Child Exercise While the Murmur Is Still Present?
A child with a confirmed innocent murmur can usually take part in play, physical education, swimming and sport without restrictions. The murmur may become easier to hear when the heart beats faster, but this does not mean that exercise is damaging a healthy heart.
When a structural heart condition is present, follow the activity guidance provided by the cardiologist rather than restricting exercise without advice. Stop the activity and seek assessment for chest discomfort, unusual breathlessness, palpitations or dizziness, and call 999 if your child faints during exercise.
Myth vs Fact
| Myth | Fact |
| Every heart murmur should disappear during childhood. | Many innocent murmurs become quieter or disappear, but some remain audible without affecting heart health, growth or normal activities. |
| A murmur that can still be heard must be getting worse. | A persistent murmur can remain unchanged for years. Its importance depends on the underlying cause, symptoms and test results. |
| If a murmur disappears, a structural heart condition has definitely closed. | The sound can change for several reasons. When a structural heart condition has been diagnosed, examination and echocardiography may be needed to confirm whether it has improved or resolved. |
| A murmur that becomes louder during a fever is becoming more serious. | Fever increases the heart rate and can make an innocent blood-flow sound easier to hear. |
| Every hole in the heart requires an operation. | Many small muscular ventricular septal defects become smaller or close naturally. Others remain open without causing significant problems, but the follow-up plan depends on the defect’s type, size and location. |
| Children should avoid exercise until an innocent murmur disappears. | A confirmed innocent murmur does not normally require activity restrictions, even when it remains audible. |
| Once an innocent murmur disappears, new symptoms can be ignored. | New breathlessness, fainting, palpitations or reduced exercise tolerance should still be medically assessed. |
Key Takeaways
- Many innocent heart murmurs become quieter or stop being heard as children grow.
- Some innocent murmurs remain audible for years without affecting heart health or normal activities.
- A disappearing murmur does not always prove that a diagnosed structural heart condition has resolved.
- Many small muscular VSDs become smaller or close naturally, but others remain open and require individual follow-up.
- Treatment decisions depend on the underlying diagnosis, not simply on whether the murmur is still audible.
- A confirmed innocent murmur does not normally require medicine, cardiology follow-up or activity restrictions.
- Call 999 if your child is not breathing, has severe breathing difficulty, suddenly develops blue or grey lips, tongue, face or skin, becomes unresponsive, cannot be woken within one minute after fainting, faints during exercise or while lying down, or does not recover normally after fainting.
FAQs
1. Can heart murmurs in children disappear on their own?
Many innocent heart murmurs become quieter or stop being heard as a child grows, although some remain audible without affecting heart health or normal activities. A murmur associated with a structural condition may also change, but the sound alone cannot confirm whether the underlying condition has improved.
2. Does a heart murmur disappearing mean the heart problem has gone?
Not always. An innocent murmur may no longer be heard because blood flow has changed as your child grows. If the murmur was linked to a structural heart condition, a medical assessment, which may include an echocardiogram, is needed to confirm whether the condition has improved or resolved.
3. At what age do innocent heart murmurs usually disappear?
There is no fixed age. Some innocent murmurs disappear during infancy or early childhood, while others remain audible into adolescence without causing health problems.
4. Can a heart murmur come and go?
Yes. Innocent murmurs can vary from one examination to another. They may be easier to hear when your child has a fever, has been exercising, is anxious or is lying in a particular position.
5. If my child’s heart murmur is still present, does it need treatment?
Not necessarily. A persistent innocent murmur does not require treatment. Whether treatment is needed depends on the underlying cause rather than whether the murmur can still be heard.
6. Can a hole in the heart close naturally?
Many small muscular VSDs become smaller or close naturally as a child grows, although the timing varies and some remain open. Larger defects, or those affecting heart function or a nearby valve, may require continued monitoring or treatment.
7. Will my child need regular follow-up for a heart murmur?
Children with a confirmed innocent murmur usually do not need long-term cardiology follow-up. If a structural heart condition is identified, your paediatric cardiologist will recommend an appropriate review schedule.
8. Can my child play sports if the heart murmur has not gone away?
If the murmur has been confirmed as innocent, your child can usually participate in normal physical activities and sports without restrictions. Activity advice may differ if an underlying heart condition is present.
9. When should I seek urgent medical advice about a heart murmur?
Call 999 if your child is not breathing, is unresponsive, has severe breathing difficulty, suddenly develops blue or grey lips, tongue, face or skin, cannot be woken within one minute after fainting, has not fully recovered, has difficulty speaking or moving, is shaking or jerking as if having a seizure, has been seriously injured, faints during exercise or while lying down, or faints with chest pain or palpitations. For worsening feeding difficulties, poor weight gain, persistent palpitations, chest discomfort or reduced exercise tolerance without emergency features, contact your GP, cardiology team or NHS 111.
10. How do doctors determine whether a heart murmur will go away?
Doctors assess your child’s symptoms, medical and family history and cardiovascular examination. If a structural condition is suspected or already diagnosed, an echocardiogram may show whether it is changing. Clinicians do not predict the outcome from the murmur’s loudness or persistence alone.
Final Thoughts: Can Heart Murmurs in Children Go Away?
Many heart murmurs in children are innocent and naturally become quieter or disappear as a child grows, while others may remain audible for years without affecting heart health. What matters most is identifying the underlying cause rather than focusing on whether the murmur can still be heard. A thorough medical assessment helps determine whether the murmur is simply a normal blood-flow sound or whether it reflects a structural heart condition that requires monitoring or treatment.
If you’re looking for expert assessment and guidance about heart murmurs in children, you can get in touch with us at London Paediatric Clinic. Our experienced team provides comprehensive evaluations, appropriate investigations where needed, and personalised advice to help you understand your child’s heart health with confidence.
References:
- Norfolk and Norwich University Hospitals NHS Foundation Trust (2024) Cardiology Advice and Referral Pathways – Paediatrics CA4073 v7. Available at: https://www.nnuh.nhs.uk/publication/download/cardiology-advice-and-referral-pathways-paediatrics-ca4073-v7/
- Royal Brompton and Harefield hospitals (no date) Innocent heart murmur in children. Available at: https://www.rbht.nhs.uk/our-services/innocent-heart-murmur-children
- Leeds Teaching Hospitals NHS Trust (2025) Heart murmur in newborn babies – What it means, what to look out for and what happens next. Available at: https://www.leedsth.nhs.uk/patients/resources/heart-murmur-in-newborn-babies-2/
- Royal Brompton and Harefield hospitals (no date) Small ventricular septal defect (VSD). Available at: https://www.rbht.nhs.uk/our-services/small-ventricular-septal-defect-vsd
- Kingston and Richmond NHS Foundation Trust (2024) Syncope (fainting) in children and young people. Available at: https://www.kingstonandrichmond.nhs.uk/patients-and-families/patient-leaflets/syncope-fainting-children-and-young-people
- NHS (2023) Blue or grey skin or lips (cyanosis). Available at: https://www.nhs.uk/symptoms/blue-skin-or-lips-cyanosis/
- NHS (2023) Fainting. Available at: https://www.nhs.uk/symptoms/fainting/
- Ford, B., Lara, S. and Park, J. (2022) Heart murmurs in children: evaluation and management. American Family Physician, 105(3), pp. 250–261. Available at: https://pubmed.ncbi.nlm.nih.gov/35289571/