Heart Murmur: What It Means, Causes, and When Testing Is Needed

A heart murmur is an extra or unusual sound heard during a heartbeat. Many murmurs are harmless, but some can point to a valve problem or another heart condition that needs evaluation.

Overview: What a heart murmur means

A heart murmur is an extra sound heard when a doctor listens to the heart with a stethoscope. Instead of only the usual “lub-dub” pattern, there may be a whooshing or swishing sound caused by blood flowing through the heart or nearby blood vessels. A murmur itself is not a disease. It is a clinical finding that may be completely harmless or may sometimes suggest an underlying heart problem.

Heart murmurs can occur in children, adults, and older people. Some are present from birth, while others develop later in life. Doctors often describe murmurs by when they happen during the heartbeat, how loud they are, where they are heard best, and whether they change with body position or activity. These details help guide whether further testing is needed.

Many people are reassured to learn that an innocent, also called functional or physiologic, murmur is common. This type happens when blood flows normally through a healthy heart but creates an audible sound. Innocent murmurs may be heard during childhood, pregnancy, fever, anemia, or exercise, and they usually do not damage the heart.

Symptoms and signs linked to a heart murmur

A heart murmur often causes no symptoms at all. In many cases, it is discovered during a routine checkup, sports physical, pregnancy visit, or evaluation for another issue. If the murmur is innocent, the person usually feels well and has no signs of heart disease.

When a murmur is related to a heart condition, symptoms depend on the underlying cause rather than the sound itself. Possible symptoms can include shortness of breath, reduced exercise tolerance, chest discomfort, dizziness, palpitations, fainting, swelling in the ankles or legs, or unusual tiredness. In infants, signs may include poor feeding, sweating with feeds, poor weight gain, or fast breathing.

Doctors also look for physical signs that may suggest a significant murmur. These can include bluish lips or fingertips, rapid breathing, abnormal pulses, or signs of fluid buildup. A person with a new murmur and symptoms should be assessed by a qualified doctor so that any valve problem, congenital heart issue, or heart failure can be identified early.

Causes and risk factors

Heart murmurs are usually grouped into innocent and abnormal murmurs. Innocent murmurs happen when blood moves quickly through a structurally normal heart. They can be heard during growth spurts in children, pregnancy, exercise, fever, anemia, or an overactive thyroid. These situations increase blood flow or change the way blood moves, creating a murmur even though the heart itself is healthy.

Abnormal murmurs are more likely when there is a problem with the heart valves or the structure of the heart. Common causes include valves that are narrowed, called stenosis, or valves that do not close properly, called regurgitation. Examples include aortic stenosis, mitral regurgitation, and other forms of heart valve disease. Some murmurs are due to congenital heart defects such as a hole between heart chambers or an abnormal valve present from birth.

Other causes can include infection of the heart valves, known as endocarditis, calcium buildup on valves with aging, rheumatic heart disease, high blood pressure, or enlargement of the heart. Risk tends to rise with age, a history of congenital heart disease, previous rheumatic fever, certain infections, and conditions that strain the heart over time. A family history of valve disease or inherited heart conditions may also play a role in some people.

How doctors diagnose a heart murmur

Diagnosis starts with a medical history and physical examination. The doctor asks about symptoms, exercise tolerance, past illnesses, medications, pregnancy, and family history of heart disease. During the exam, the heart is listened to carefully to assess the murmur’s timing, intensity, pitch, and location. The doctor also checks blood pressure, oxygen levels, pulses, lung sounds, and signs of swelling or poor circulation.

If the murmur appears innocent and the person has no concerning symptoms or exam findings, no further testing may be necessary. When there is any concern about a structural cause, the most useful test is an echocardiogram. This ultrasound scan shows the heart chambers, valves, blood flow, and pumping function in real time. It can confirm whether the murmur is harmless or related to a specific condition.

Other tests may be used depending on the situation. These can include an electrocardiogram to assess heart rhythm, a chest X-ray to look at heart size and the lungs, blood tests to check for anemia or infection, and sometimes exercise testing. If a murmur suggests a significant valve problem, doctors may arrange advanced imaging or detailed cardiology evaluation to plan the next steps.

Treatment options and follow-up

Treatment depends entirely on the cause. Innocent murmurs do not need treatment because the heart is normal. In these cases, the main approach is reassurance and routine medical follow-up as advised. People can usually continue normal daily activities, school, work, and exercise unless a doctor recommends otherwise for another reason.

When a murmur is caused by an underlying medical issue, treatment focuses on that condition. Anemia, fever, thyroid disease, or high blood pressure may improve once managed appropriately. If the cause is a valve disorder, treatment may range from monitoring with regular echocardiograms to medicines that help the heart work more efficiently, depending on the problem and symptoms.

Some people eventually need a procedure or surgery, especially if a valve becomes severely narrowed or leaky or if a congenital defect affects heart function. Depending on the diagnosis, care may involve heart valve surgery or a catheter-based treatment. If the murmur is due to a structural problem present from birth, a specialist may discuss options used in congenital heart surgery. Near the end of the care pathway, some international patients seek assessment at Acibadem International, where multidisciplinary specialists in JCI-accredited hospitals diagnose and treat heart conditions.

Prevention and self-care

It is not always possible to prevent a heart murmur because many are innocent or related to conditions present from birth. Still, protecting heart health can reduce the risk of some causes, especially acquired valve disease and heart strain. Managing blood pressure, cholesterol, diabetes, and body weight supports long-term cardiovascular health.

Good self-care also includes regular exercise suited to personal health, a balanced diet, not smoking, and limiting excess alcohol. People with known valve disease should attend follow-up appointments and imaging tests as recommended. Anyone with symptoms that change over time should report them rather than assuming the murmur is still harmless.

Preventing infections matters for some people, especially those at higher risk of valve complications. Good dental hygiene and routine dental care are important because certain infections can affect heart valves. A doctor can explain whether any special precautions are needed before dental or medical procedures, as this advice depends on the person’s specific heart condition.

When to see a doctor

A person should see a doctor if a heart murmur is newly discovered, especially if there are symptoms or a history of heart disease. Even though many murmurs are harmless, only a proper examination can tell whether testing is necessary. Medical review is also important if a previously known murmur seems to be associated with new fatigue, shortness of breath, swelling, dizziness, or reduced exercise capacity.

Urgent medical care is needed for warning signs such as chest pain, fainting, severe shortness of breath, blue lips, or signs of stroke. Parents should seek prompt assessment for infants with trouble feeding, sweating during feeds, fast breathing, or poor growth. These signs do not always mean a serious heart problem, but they should not be ignored.

After evaluation, many people are told their murmur is innocent and can be monitored routinely. Others may need specialist care and repeat imaging over time. A clear diagnosis helps guide safe activity, future checkups, and treatment decisions if they become necessary.

Frequently asked questions

Is a heart murmur always serious?

No. Many heart murmurs are innocent, meaning the heart is structurally normal and no treatment is needed. A doctor may still evaluate the murmur to make sure it is not linked to a valve or other heart problem.

Can adults develop a heart murmur later in life?

Yes. Adults can develop a new murmur because of valve changes, anemia, pregnancy, infection, or other conditions that affect blood flow. A new murmur in adulthood often deserves medical assessment, especially if symptoms are present.

What test is most commonly used to check a heart murmur?

The most common test is an echocardiogram, which is an ultrasound of the heart. It shows the heart valves, chambers, and blood flow, helping doctors tell whether the murmur is innocent or abnormal.

Can a heart murmur go away on its own?

Sometimes. Innocent murmurs in children may disappear as they grow, and murmurs related to fever, anemia, or pregnancy may improve when the underlying cause resolves. Murmurs caused by valve disease usually do not go away without treating the underlying problem.

Is exercise safe with a heart murmur?

In many cases, yes, especially if the murmur is innocent and there are no symptoms. However, if the cause is unknown or a structural heart problem is suspected, a doctor should advise on safe activity levels before intense exercise or competitive sports.

Can children have heart murmurs?

Yes. Heart murmurs are common in children, and many are innocent. Some murmurs in babies and children are due to congenital heart conditions, which is why a pediatric assessment may be recommended when the murmur has concerning features.

References

• American Heart Association
• National Heart, Lung, and Blood Institute
• Mayo Clinic
• NHS
• European Society of Cardiology

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.