WHAT IS HEART MURMUR

This is an unexpected sound that a doctor hears when they listen to the beating of someone’s heart through a stethoscope. They can hear the normal sounds made by the blood flowing through the heart, and of the heart valves opening and closing. If there is alteration to the smooth flow of blood through the heart this can be heard as a ‘murmur’. These can be heard when the heart relaxes – knownas a ‘diastolic’ murmur – or when it contracts, calleda ‘systolic’ murmur.

¤ CAUSES
Many murmurs are completely harmless – pregnant women often have them because of the increased amount of blood in their circulation for example – and the heart can be totally healthy and still have a murmur, such as sometimes occurs in people with anaemia. This means it is quite possible to have a heart murmur and require no treatment.

Sometimes murmurs are caused by congenital conditions such as a hole in the heart, or if there are problems with the heart valves such as prolapsed, leaking or narrowed valves.

About 30% of children will have a heart murmur at some time, but the vast majority of these are harmless (or ‘innocent’), disappearing as the child gets older or by the time they reach puberty.

Common conditions can make your heart beat faster and lead to heart murmurs. It can happen if you're pregnant or if you have:

• Anemia
• High blood pressure
• Overactive thyroid
• Fever

It could also be a problem with a heart valve. The valves close and open to let blood flow through the heart's two upper chambers (the atria) and two lower chambers (the ventricles). Valve problems include:

Mitral valve prolapse: Normally, your mitral valve closes completely when the lower left chamber of your heart contracts. It stops blood from flowing back into the upper left chamber. If part of that valve balloons out so that it doesn't close properly, you have mitral valve prolapse. This causes a clicking sound as your heart beats. It's fairly common and it's often not serious. But it can lead to the blood flowing backward through the valve, also called regurgitation.

Mitral valve or aortic stenosis: Your mitral or aortic valves are on the left side of your heart. If they narrow, which doctors call stenosis, your heart must work harder to pump blood out to the rest of your body. If untreated, it can wear out your heart and can lead to heart failure. You might be born with this condition. It can also happen as part of aging, or as a result of scarring from infections, such as rheumatic fever.

Aortic sclerosis and stenosis: One in three elderly people have a heart murmur due to the scarring, thickening, or stiffening (which doctors call sclerosis) of the aortic valve, although it hasn't narrowed. It's usually not dangerous, since the valve can work for years after the murmur starts. Aortic sclerosis is usually seen in people who have heart disease. But over time, the valve can narrow, also called stenosis. This can lead to chest pain, shortness of breath, or passing out. In some cases, the valve may need to be replaced.

Mitral or aortic regurgitation: In this case, regurgitation means the blood is going the wrong way through the mitral valve or the aortic valve. To counteract this backflow, the heart must work harder to force blood through the damaged valve. Over time, this can weaken or enlarge the heart and can lead to heart failure.

Congenital heart defects: About 25,000 babies are born each year with heart defects, such as holes in heart walls or abnormal heart valves. Surgery can correct many of these problems.

Treatment

Many children and adults have harmless heart murmurs, which don't need treatment.

If another condition, such as high blood pressure, is causing your heart murmurs, your doctor will treat the underlying cause.

Some types of heart valve disease may require medication or surgery:

• Medicines to prevent blood clots, control irregular heartbeat or palpitations, and lower blood pressure
• Diuretics to remove excess salt and water from the body, making it easier for your heart to pump
• Surgery to correct heart defects someone is born with
• Surgery to correct certain types of heart valve disease
• It's not common, but doctors sometimes ask people to takeantibiotics to help prevent heart infection before dental work or some kinds of surgery.

Diagnosis

Usually, doctors find heart murmurs during a physical exam. Your doctor will be able to hear your heart murmur when listening to your heart with a stethoscope.

Your doctor may order one or more of the following tests to see whether your heart murmur is innocent or whether it is caused by acquired valve disease or a defect you were born with:

• Electrocardiogram (ECG), which measures the electrical activity of the heart
• Chest X-rays to see if the heart is enlarged due to heart or valve disease
• Echocardiography, which uses sound waves to map the heart's structure

What About Prevention?

In most cases, you can't prevent heart murmurs. The exception: Treating an underlying condition, such as high blood pressure, or avoiding heart valve infection, can stop heart murmurs before they start.

When to Call Your Doctor

Call your doctor about a heart murmur if you feel:

• Chest pain
• Breathlessness, fatigue, or fainting for no obvious reason
• Heart palpitations

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