What is a Heart Murmur?

A heart murmur is a sound that occurs when blood flows abnormally through the heart or heart valves. This condition is common and usually not a cause for concern.

When the heart beats, it makes two rhythmic sounds in a row with a noise that is described as “lub-dub.” If a heart murmur is present, the sound is different and often is described as a “swish” or “whoosh.” These “swish” and “whoosh” sounds can be heard with a stethoscope; heart murmurs are not audible to the human ear.

Most heart murmurs are not harmful and do not need treatment. These are called “innocent” murmurs, and they are common in babies and children. Sometimes, however, a murmur is a sign of a heart abnormality. If your doctor detects a murmur, they may recommend additional testing of your heart and valves.

Types of Heart Murmurs

Murmurs vary in terms of how loud they are, when they occur and how long they last. Health care providers assign a rating to heart murmurs, on a scale of 1 to 6. Murmurs with a rating of 1 are very quiet while those with a rating of 6 are loud.

Heart murmurs are divided into categories, depending on when they occur during the heartbeat cycle:

Systolic

A murmur heard when the heart muscle contracts and pushes blood out of the heart is called a systolic murmur. If the noise is heard when the blood flows through a faulty valve or vessel, it is an ejection murmur. If the noise is heard when the blood flows backwards through the valves or vessels, it is a regurgitant murmur.

Diastolic

A murmur heard when the heart muscle relaxes between beats is called a diastolic murmur.

Continuous

A continuous murmur can be heard when the heart muscle contracts and also when it relaxes. Continuous murmurs occur throughout the entire heartbeat cycle.

Systolic murmurs are often innocent murmurs. Diastolic or continuous murmurs are more likely to indicate a cardiac problem.

What are the Causes of Heart Murmurs?

Innocent murmurs are not caused by heart abnormalities. Instead, they result from changes in blood flow due to temporary situations, including infections or having a fever, iron deficiency, overactive thyroid, growth spurts in children, increased physical activity or pregnancy. These murmurs may come and go at different times without causing other health problems.

Murmurs related to other cardiac conditions that may need treatment can be caused by:

  • Structural problems in the heart, including holes in the heart or valve defects
  • Heart disease, including hypertrophic cardiomyopathy (thickening of the heart tissue)
  • Heart valve disease, including valve stenosis (narrowing of a valve) and valve regurgitation (blood moving in the wrong direction)
  • Heart infections, including endocarditis (bacterial infection that affects the heart lining and valves)

What are the Symptoms of Heart Murmurs?

Innocent murmurs generally do not cause symptoms and are often discovered during a routine exam by a health care provider.

Murmurs related to other cardiac conditions may cause symptoms. The symptoms vary, depending on the cause, and may include:

  • Chest tightness or chest pain
  • Shortness of breath
  • Persistent cough
  • Lightheadedness, dizziness or fainting
  • Heart palpitations
  • Increased perspiration
  • Sudden weight gain
  • Bluish fingernails, lips or skin

Heart Murmurs Risk Factors and Prevention

Babies born to mothers with uncontrolled diabetes or to mothers who use alcohol or drugs during pregnancy have an increased risk of heart murmurs.

In adults, certain cardiac conditions can increase the risk of developing heart murmurs. Heart infections, heart disease, high blood pressure, blood disorders or autoimmune disease may increase the risk for heart murmurs.

Heart murmurs cannot be prevented, but maintaining a heart-healthy lifestyle can reduce the risk of cardiac conditions related to murmurs. Children with heart murmurs often “outgrow” the condition as they get older.

How is a Heart Murmurs Diagnosed?

Many murmurs are diagnosed while a health care provider is listening to the heart with a stethoscope. If a murmur is detected, your provider may recommend testing to determine whether the murmur is innocent, or if it indicates a heart problem. Testing can include:

Echocardiogram

This test uses sound waves to see the blood flow through the heart and heart valves to detect heartbeat abnormalities.

Electrocardiogram

Also called an EKG or ECG, this test measures the heart’s electrical activity.

Chest X-ray

X-ray technology takes a picture of the heart to identify enlargement or other structural defects.

Treatment for Heart Murmurs

Innocent murmurs generally do not require any treatment. Sometimes they go away on their own, or they may persist but do not typically cause problems.

Murmurs caused by conditions like anemia (low iron levels) or hyperthyroidism (overactive thyroid) may disappear if the underlying condition is resolved.

If a murmur is caused by another heart problem, medication or surgical intervention may be necessary.

Medication

Treating underlying conditions that cause murmurs with medication can be beneficial. These medications can include blood thinners to prevent blood clots, ACE inhibitors, beta blockers or diuretics to lower blood pressure.

Surgery

Murmurs that are caused by structural heart problems can be resolved by surgical intervention to correct the underlying problem. Depending on the specific condition, procedures can include minimally invasive or open heart surgery to repair damaged heart valves or to patch holes in the heart.

Advanced Heart Care from Memorial Hermann

The experienced heart and vascular specialists affiliated with Memorial Hermann are dedicated to diagnosing, treating and managing a wide range of cardiac conditions with a patient-centered approach.

If your heart murmur is caused by an underlying cardiac condition, it is important to identify and control or correct the problem. From minimally invasive cardiac therapies to complex open heart surgical interventions, Memorial Hermann is at the forefront of innovative technology and the latest research to keep you heart-healthy.

Contact Us

If you’d like a referral to a heart and vascular specialist or want more information about our services, please fill out the form below or call us at (713) 219-3519. For other inquiries, such as obtaining medical records, imaging reports or test results, please call (713) 222-CARE (2273).

Thank
You!

Thank you for your inquiry and for connecting with Memorial Hermann Heart & Vascular. If you’re ready to be connected to a heart & vascular specialist now, you can move on to the referral request step by providing your insurance information. This, along with any provider and/or location preferences, will assist us in connecting you with the appropriate Memorial Hermann-affiliated specialist. If you’d like more time, our Nurse Navigator will reach out via email and provide a link to the form that you can submit at your convenience.

We are dedicating to providing you direct access to a comprehensive care team, including specialists who are committed to providing high-quality heart and vascular care.

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