An Overview of Heart Murmurs

Stethoscope Checking Heart Beat
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A heart murmur is an extra or abnormal sound that is heard during cardiac auscultation (when your doctor listens to your heart with a stethoscope).

A murmur doesn't cause noticeable effects on its own. Often, heart murmurs are completely harmless and are not associated with any health problems at all. But some heart murmurs are caused by heart disease, and you may experience fatigue, shortness of breath, or other complications of your heart condition.

If a murmur is detected, the cause can usually be identified with a non-invasive test. Sometimes interventional diagnostic tests are necessary. If there is a serious cause of your heart murmur, surgical or medical treatment can often correct the problem and prevent complications.

Symptoms

Heart murmurs affect people of all ages, ranging from newborns to elderly adults. A heart murmur can begin at any age, and it may change throughout a person's life.

Many heart murmurs, called "innocent" murmurs, do not cause symptoms, so you would not be able to know if you have one unless you are diagnosed by a doctor. Other murmurs, called "abnormal" murmurs, can cause symptoms and may be a symptom of a heart disease that left untreated could cause serious health issues.

Nevertheless, there are some signs that can alert you to a heart murmur, including:

  • Fatigue, low energy
  • Occasional lightheadedness or dizziness
  • Shortness of breath, especially with physical exertion
  • Palpitations (a sense that you have a rapid or irregular heartbeat)

Congenital Heart Conditions

Sometimes, children are born with heart problems. These conditions may cause serious effects right at birth or during childhood. Babies who have a heart murmur may have bluish skin, especially on the fingers or lips. This is often a medical emergency.

Children who have mild heart conditions may have less than expected weight gain and can be shorter than their expected height. They may have exercise intolerance—or may simply complain that they don't like sports or gym class.

Complications

While it is rare, a heart condition can result in sudden health effects, such as a heart attack or a stroke—without any warning signs beyond a heart murmur. A heart attack can cause severe chest tightness, shortness of breath, and chest or arm pain. A stroke can cause weakness on one side of the body, vision changes, speech alterations, or confusion.

The effects associated with a heart murmur are vague and can be signs of other medical illnesses as well. Be sure to talk to your doctor promptly if you or your child experience symptoms such as shortness of breath, fatigue, or palpitations.

Causes

Heart murmurs are extra sounds that are made by the heart during a heartbeat. Normally, the heart contracts and expands following a regular rhythm that produces sounds described as "lub dub." These sounds can be heard with a stethoscope.

A murmur can also be heard with a stethoscope and it is caused by a change in the motion of the heart muscles or the heart valves. These changes can be caused by a variety of heart diseases.

The most common causes of heart murmurs differ depending on a person's age:

  • Older adults: Murmurs are most common among adults over the age of 60. They can be caused by a heart valve problem, such as prolapse, stenosis, or regurgitation. Other issues, such as endocarditis (a heart infection), arrhythmias (abnormal heart rhythm), or a previous heart attack can cause a murmur as well.
  • Babies and children: A murmur may be the result of a congenital heart defect, such as Tetralogy of Fallot and sepal defects.
  • Young adults: A murmur could be due to a structural problem that was not diagnosed in childhood, or it could develop due to a heart condition that was acquired later in life, such as the conditions that cause heart murmurs in older adults.
  • Pregnant women: While pregnant women can develop serious heart disease, it is not common. Pregnancy may cause a murmur that is often described as an "innocent murmur." This is believed to occur due to increased blood volume flowing through the blood vessels—which places extra work on a woman's heart.

Diagnosis

Your doctor, and possibly a cardiologist (a specialized heart doctor) may detect a heart murmur during your routine cardiac auscultation. It can be louder or last a bit longer than your other heart sounds. However, sometimes heart murmurs are quiet and may not be easy to hear, or they can come and go.

And while your doctor may be able to determine the cause of your heart murmur by listening to your heart sounds with a stethoscope, additional tests are usually necessary to better assess your heart structure and function.

Types of Heart Murmurs

The vast majority of murmurs do not indicate a serious problem. A heart murmur that is present in a normal and healthy heart is called an innocent murmur.

These murmurs are common in infants and children, who can outgrow their heart murmurs completely. Adults may also have innocent murmurs.

The other type of heart murmur, an abnormal murmur, is a sign of heart disease. If there is a chance that your murmur is not an innocent murmur, you may need further testing.

Diagnostic Tests

There are several tests that can be used to assess the structure and function of your heart. You may have one or more of these as your medical team evaluates the cause of your heart murmur.

  • Electrocardiogram (EKG): An EKG is a non-invasive test that is used to assess heart rhythm. You would have leads (flat metal plates attached to wires) placed on your chest to produce a tracing that reflects your heart rhythm.
  • Echocardiogram: An echocardiogram, often referred to as an echo, is a non-invasive ultrasound of the heart. You would have a small device placed on your chest, which produces a video of your heart in action. Your heart rhythm and its anatomical structure (including the valves) can be evaluated using this test.
  • Cardiac catheterization: This is an interventional diagnostic test that allows your medical team to look inside your heart. During this procedure, a wire (sometimes with a camera) is placed into a blood vessel (usually in the arm or groin) and threaded up into the heart. Detailed information about the valves, blood vessels, and blood pressure can be obtained using this test to assess the cause of your murmur.

Treatment

Some heart murmurs are caused by conditions that require surgical treatment and/or require medical management, while some do not require any intervention at all. If you have a heart condition that does not require immediate treatment, your medical team will periodically assess your heart function.

Surgery

In some situations, emergency surgery may be necessary. Babies born with severe congenital heart defects may require repair. And some anatomical defects have to be repaired in stages, with several surgeries. Some children may have to wait until they are physically bigger before having a heart defect repaired

Heart surgery for children and adults can involve open-heart surgery, in which the chest is opened for the procedure. In some instances, a minimally invasive procedure that uses a catheter is used to repair the heart.

Medical Management

There are some medical approaches for treating heart problems that cause murmurs.

An arrhythmia can often be treated with prescription medication. In some cases, this corrects the heart murmur.

Sometimes medications are used to prevent complications, but cannot treat the underlying problem. Often, people who have valve disease need to use antibiotics before dental procedures. This is because the valves are predisposed to becoming infected.

Some people who have valve disease, arrhythmias, or aortic disease (the aorta is a large blood vessel the sends blood from the heart to the body) may need to use a blood thinner to prevent blood clots.

A Word From Verywell

Heart sounds can change throughout the lifespan. A murmur that is present in childhood may resolve as the child grows into an adult. An adult may develop a murmur, which may be a sign of a problem with the heart.

It is important to remember that many people have heart murmurs and live long and healthy lives with no need for treatment at all.

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Article Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial policy to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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