Heart murmurs - Causes, Symptoms & Treatment

Physical exam

A heart murmur is an unexpected or unusual sound which can be heard in your heart through a stethoscope.

They are mostly harmless, but sometimes they can relate to a problem with your heart.

What is a heart murmur?

When a doctor listens to your heart with a stethoscope, they can hear the sounds made by the blood flowing through the heart, and by the valves in your heart opening and closing. These are normal sounds that the doctor would expect to hear.

A heart murmur is an extra or unusual sound which may be heard. It may be caused by a related heart problem, but often there is no cause at all.

‘Innocent’ heart murmurs in children

Heart murmurs are quite common in children. They are sometimes described as ‘innocent’ heart murmurs. This is because they are usually harmless and not caused by a problem with the heart. 

Innocent murmurs may come and go, or they may vary depending on the child’s physical position, breathing and heart rate. They usually disappear by the time the child reaches puberty.

What can cause a heart murmur?

Murmurs can be heard when the heart contracts (a systolic murmur) or when the heart relaxes (a diastolic murmur). People who have a healthy heart can sometimes have murmurs.

Doctors can often tell the difference between different types of murmurs by the sound they make, and can identify murmurs that might be linked to a problem with your heart.

Sometimes heart murmurs are heard because of a problem with one of the heart’s valves. Heart valve defects can be minor and cause no wider health problems. But there can be more serious problems that may need treatment – for example if the heart valve is narrowed, prolapsed (weak or floppy) or leaking.

Other causes of heart murmurs include congenital heart defects, such as a hole in the heart. A congenital heart condition is a condition that develops when a baby is in the womb.

People with anaemia can have heart murmurs. They are also often heard in pregnant women, because of the unusually large amount of blood flowing through a pregnant woman’s heart.

Will I need to have treatment?

A heart murmur itself doesn’t need treatment, but sometimes if the murmur is caused by a problem with your heart, then the cause of the murmur may need treatment. Your doctor will be able to tell you if you need to have treatment, depending on what the cause of the murmur is and any other symptoms you may have.

If your doctor thinks your murmur may be caused by a heart problem, they will usually arrange for you to have an echocardiogram (an ultrasound of your heart). This test will show if there are any problems with the structure of your heart, or with your heart’s valves.

If you do need treatment, your options may include taking medicines to control your symptoms, or having heart surgery to fix more serious problems. For example, if there is a severe problem with one of your heart valves, you may need surgery to repair or replace the valve. Your doctor can speak to you about this.

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