Heart Murmurs

1 What are Heart Murmurs?

Heart murmurs are sounds during your heartbeat cycle such as whooshing or swishing that is made by turbulent blood in or near the heart.

These sounds can be heard with a stethoscope. A normal heartbeat makes two sounds like "lubb-dupp" (sometimes described as "lub-DUP"), which are the sounds of heart valves closing.

Heart murmurs can be present at birth (congenital) or develop later in life. A heart murmur isn't a disease — but murmurs may indicate an underlying heart problem.

Often, heart murmurs are harmless (innocent) and don't need treatment. Some heart murmurs may require follow-up tests to be sure the murmur isn't caused by a serious underlying heart condition.

Treatment, if needed, is directed at the cause of the heart murmur.

2 Symptoms

If anyone has a harmless heart murmur, more commonly known as an innocent heart murmur, they likely won't have any other signs or symptoms.

An abnormal heart murmur may cause no obvious other signs or symptoms, aside from the unusual sound the doctor hears when listening to the heart with a stethoscope.

But if you have these signs or symptoms, they may indicate a heart problem:

Most heart murmurs aren't serious, but if an individual thinks they or their child has heart murmur, an appointment must be made to see the family doctor.  

3 Causes

The causes of heart murmurs vary depending on its type.

There are basically two types of heart murmur. These are innocent murmurs and abnormal murmurs.

A person with an innocent murmur has a normal heart. This type of heart murmur is common in new-borns and children.

An abnormal heart murmur is more serious. In children, abnormal murmurs are usually caused by congenital heart disease. In adults, abnormal murmurs are most often due to acquired heart valve problems.

An innocent murmur can occur when blood flows faster than normal through the heart. Conditions that may cause rapid blood flow through your heart, resulting in an innocent heart murmur, include:

  • Physical activity or exercise,
  • pregnancy,
  • fever,
  • lack of enough healthy red blood cells to carry adequate oxygen to your body tissues (anaemia),
  • an excessive amount of thyroid hormone in the body (hyperthyroidism)
  • and phases of rapid growth, such as adolescence.

The most common cause of abnormal murmurs in children is when babies are born with structural problems of the heart (congenital heart defects).

Common congenital defects that cause heart murmurs include:

  • Holes in the heart or cardiac shunts which are also known as septal defects,
  • holes in the heart may or may not be serious, depending on the size of the hole and its location.

Cardiac shunts occur when there's an abnormal blood flow between the heart chambers or blood vessels, which may lead to a heart murmurs.

Congenital heart valve abnormalities are present at birth, but sometimes aren't discovered until much later in life. Examples include valves that don't allow enough blood through them (stenosis) or those that don't close properly and leak (regurgitation), such as mitral valve prolapse.

Other causes of abnormal heart murmurs include infections and conditions that damage the structures of the heart and are more common in older children or adults.

For example: Valve calcification. This hardening or thickening of valves, as in mitral stenosis or aortic valve stenosis, can occur as you age. Valves may become narrowed (stenotic), making it harder for blood to flow through the heart, resulting in murmurs.

Endocarditis is an infection of the inner lining of the heart and valves typically occurs when bacteria or other germs from another part of your body, such as your mouth, spread through your bloodstream and lodge in the heart. Left untreated, endocarditis can damage or destroy the heart valves. This condition usually occurs in people who already have heart valve abnormalities.

Although now rare in places like the United States, rheumatic fever is a serious condition that can occur when one does not receive prompt or complete treatment for a strep throat infection. It can permanently affect the heart valves and interfere with normal blood flow through the heart.

4 Making a Diagnosis

Making a diagnosis of heart murmurs is usually done during physical exam.

If any parents suspects their child is having heart murmurs, it is important to take immediate action and make a doctors appointment.

Although many heart murmurs are harmless, it is always advantageous to rule out any underlying conditions that may develop. Because appointments can be brief, it is advisable to be prepared before hand.

The following information can prepare any individual for their appointment with the doctor:

  • Knowing what to expect from the doctor.
  • What you can doand be aware of any appointment restrictions.

At the time one makes the appointment, it is vital to be sure to ask if therw are any advance preparations. For instance, if one is having a certain typ of eectrocardiogram, they may need to fast for several hours before the appointment.

Writing down any symptoms experienced, including any that mayseem unrelated to the heart murmurs.

Writing down any other key information, including

  • a family history of murmurs including a family history of heart murmurs,
  • heart rhythm problems,
  • heart defects,
  • coronary artery disease,
  • genetic disorders,
  • stroke,
  • high blood pressure
  • or diabetes,

and any major stresses or recent life changes. Making a list of all medications, vitamins or supplements that are being taken.

Write down questions to ask the doctor

For heart murmurs, some basic questions to ask the doctor include:

  • What's the most likely cause of the heart murmur?
  • What are other possible causes for the heart murmur?
  • What kinds of tests are necessary?
  • What's the best treatment or follow-up care?
  • What are the alternatives to the primary approach that you're suggesting?
  • How should health conditions other than the heart murmur be managed?
  • Are there any dietary or exercise restrictions that I need to follow?
  • Should I see a specialist?
  • If surgery is necessary, which surgeon do you recommend?
  • Is there a generic alternative to the medicine you're prescribing?
  • Are there any brochures or other printed material that I can take home with me?
  • What websites do you recommend visiting?

The doctor may also ask the following questions

  • When did you or your child first have symptoms?
  • Have the symptoms been continuous or occasional?
  • How severe are the symptoms?
  • What, if anything, seems to make your symptoms better?
  • Does anything make the symptoms worse?
  • Have you ever noticed a bluish discoloration of the skin?
  • Do you have shortness of breath?
  • When does this happen?
  • Have you ever fainted?
  • Have you had chest pain?
  • Have you had swelling in your legs?
  • How do you feel when you exercise?
  • Have you ever used illicit drugs?
  • Have you ever had rheumatic fever?
  • Does anyone else in the family have a heart murmur or a heart valve problem?

Heart murmurs are usually detected when a doctor listens to the heart using a stethoscope during a physical exam.

To check whether the murmur is innocent or abnormal, doctors usually consider:

  • How loud is it? This is rated on a scale from 1 to 6, with 6 being the loudest.
  • Where in the heart is it? And can it be heard in your neck or back? What pitch is it?
  • Is it high-, medium- or low-pitched?
  • What affects the sound? If body position is changed, does it affect the sound?
  • When does it occur, and for how long?

If your murmur happens when the heart is filling with blood (diastolic murmur) or throughout the heartbeat (continuous murmur), that may mean one has a heart problem.

The following tests can also help in the diagnostic process: Chest X-ray, Electrocardiogram (ECG) and Cardiac catheterization

5 Treatment

An innocent heart murmur generally doesn't require treatment because the heart is normal.

If treatment is necessary (in the case of abnormal murmurs), it depends on what heart problem is causing the murmur and may include medications or surgery.

The medication prescribed depends on the specific heart problem that one may have.

Some medications prescribed by the doctor include: Medications that prevent blood clots (anticoagulants) such as aspirin, warfarin (Coumadin, Jantoven) or clopidogrel (Plavix).

Diuretics remove excess fluid from the body, which can help treat other conditions that might worsen a heart murmur, such as high blood pressure.

ACE inhibitors lower blood pressure. High blood pressure can worsen underlying conditions that cause heart murmurs.

Statins help lower  cholesterol. Having high cholesterol seems to worsen some heart valve problems, including some heart murmurs.

Beta blockers can also be used lower your heart rate and blood pressure. They're used for some types of heart valve problems.

Many valve conditions can't be treated with medications alone. Depending on heart condition, a doctor may recommend one of these options to treat a damaged or leaky valve: Valve repair using the following procedures: Balloon valvuloplasty. During a balloon valvuloplasty, a small catheter containing an expandable balloon is threaded into the heart, placed into the valve and then expanded to help widen the narrowed valve.


In this procedure, a surgeon tightens the tissue around the valve by implanting an artificial ring. This allows the leaflets to come together and close the abnormal opening through the valve. Repair of structural support. In this procedure, your surgeon replaces or shortens the cords that support the valves (chordae tendineae and papillary muscles) to repair the structural support. When the cords and muscles are the right length, the valve leaflet edges meet and eliminate the leak.

Valve leaflet repair

In valve leaflet repair, a surgeon surgically separates, cuts or pleats a valve flap (leaflet). In many cases, the valve has to be replaced.

Options include: Open-heart surgery, mechanical valves, made from metal, are durable, but carry the risk of blood clots forming.

Anyone receiving a mechanical valve, needs to take an anticoagulant medication, such as warfarin (Coumadin, Jantoven), for life to prevent blood clots. Tissue valves — which may come from a pig, cow or human deceased donor — often eventually need replacement.

Another type of tissue valve replacement that uses your own pulmonary valve (autograft) is sometimes possible.

6 Prevention

There's not much one can do to prevent a heart murmur, it is reassuring to know that heart murmurs are not a disease and are often harmless.

For children, many murmurs go away on their own as children grow.

For adults, murmurs may disappear as the underlying condition causing them improves.

7 Risks and Complications

There are several risk factors that increase one’s chances of developing a heart murmur. These risk factors include family history of a heart defect.

If blood relatives have had a heart defect, the possibility of anyone related to them having heart murmurs increases.

Certain medical conditions, including:

Factors that increase a baby's risk of developing a heart murmur include:

  • Illnesses during pregnancy such as uncontrolled diabetes or a rubella infection,
  • increases a baby's risk of developing heart defects and a heart murmur.

Another way is by taking certain medications or illegal drugs during pregnancy. Use of certain medications, alcohol or drugs can harm a developing baby, leading to heart defects.