Systolic Heart Murmur


What is a systolic murmur?

A systolic (sis-TOL-ic) heart murmur is an unusual heart sound that occurs when your heart contracts (systole, pronounced SIS-tah-lee). This sound is a result of turbulent blood flow. Your heart beat is the sound of the valves in your heart closing. The first sound is closure of atrioventricular valves (mitral and tricuspid valves). The second sound is closure of semilunar valves (aortic and pulmonic valves). Systole is the first part of your heartbeat when the atrioventricular valves should be closed. The top number in a blood pressure measurement reflects the systolic pressure during your heart’s contraction.

A systolic murmur may sound like a “swish” or “whoosh” after the first heart sound. Blood moving in your heart across a valve is the most common cause of this sound.

Often, heart murmurs aren’t dangerous. But sometimes, they can point to an underlying heart condition. If you have a heart murmur, it’s important to see a healthcare provider for testing.

What are the types of systolic heart murmurs?

Providers may categorize systolic heart murmurs as:

  • Functional: People with functional murmurs don’t have any problems with their heart’s structure.
  • Organic: People with organic murmurs have the murmur because of an issue with their heart’s structure.

Systolic murmurs may also be one of two types:

  • Ejection murmurs typically start in the semilunar valves. These heart valves connect your aorta and pulmonary arteries to your heart. Ejection murmurs may be functional or organic.
  • Regurgitant murmurs occur when your heart valves don’t close properly, causing blood leakage backwards. These typically start in the atrioventricular valves. All regurgitant systolic murmurs are organic.

What is the difference between a systolic and diastolic heart murmur?

All heart murmurs are unusual sounds during your heartbeat.

In systolic heart murmurs, the sound occurs your heart muscle contracts at the beginning of or during a heartbeat. In diastolic heart murmurs, this sound occurs when your heart muscle relaxes between beats.

What is the difference between an innocent and abnormal heart murmur?

Sometimes, heart murmurs aren’t a sign of a heart problem. Healthcare providers call these innocent heart murmurs. Other times, heart murmurs are a symptom of an underlying condition. Providers classify these as abnormal heart murmurs.

An innocent heart murmur usually doesn’t need treatment. If you have an abnormal heart murmur, you likely need treatment targeted for the underlying cause.

Symptoms and Causes

What causes a systolic heart murmur?

Ejection murmurs may occur because of:

  • Aortic stenosis: Narrowing in the aortic valve, which lets blood pass from your heart to your aorta.
  • Atrial septal defect: A hole in the atrial septum which is the wall separating your heart’s two upper chambers (atria).
  • Hypertrophic obstructive cardiomyopathy: A genetic heart condition where the septum between your heart’s two lower chambers (ventricles) thickens.
  • Pulmonic stenosis: Narrowing in the pulmonary valve that connects your heart and lungs.

Regurgitant murmurs may occur because of:

  • Mitral valve regurgitation: Normally blood leaves the left atrium (left-sided upper chamber) during diastole (heart filling period) through the mitral valve before it enters the left ventricle (left-sided bottom heart chamber). During systole (heart contraction period), these valves close allowing the one-directional flow of blood. However, in mitral regurgitation, blood flow leaks backward into the left atrium during systole.
  • Tricuspid valve regurgitation: The tricuspid valve separates the right atrium (right upper chamber) from the right ventricle (right bottom chamber). During cardiac filling, the valve opens to allow blood to fill the ventricle and closes during diastole to allow one-way forward blood flow. However, in tricuspid regurgitation blood flow leaks backward into the right atrium during systole.
  • Ventricular septal defects: A hole in the wall between your heart’s ventricles.

What are the symptoms of a systolic murmur?

Some people who have heart murmurs don’t have any noticeable symptoms. Depending on the cause of the heart murmur, you may have:

Diagnosis and Tests

How is a systolic murmur diagnosed?

Typically, your provider detects a systolic murmur while listening to your heart with a stethoscope. Your doctor may evaluate the sound’s:

  • Length.
  • Location.
  • Pitch and volume.
  • Changes when you do things like shift your position.

What tests might I have to diagnose a systolic heart murmur?

If you need more tests, your provider may refer you to a cardiologist (a healthcare provider specializing in the heart). Heart tests give the cardiologist information about your heart’s structure and rhythm. You may have:

  • Cardiac catheterization involves placing a small tube (catheter) into your groin or arm. Using X-rays and contrast dye, your cardiologist looks at your arteries.
  • Chest X-rays use targeted radiation beams to show images of your bones, heart and lungs.
  • Echocardiograms use ultrasound waves to make an image of the movement of your heart.
  • Electrocardiograms (EKGs) record electrical activity in your heart.

What is the systolic murmur grading scale?

Your healthcare provider may assess a systolic murmur based on its intensity. A grading scale measures a murmur’s duration, volume and pitch.

Healthcare providers categorize heart murmurs on a scale of one through six. A score of one is the quietest murmur, and six is the strongest or most intense.

Management and Treatment

How is a systolic heart murmur treated?

If the murmur is innocent, it usually goes away without treatment. If you have an abnormal heart murmur, you may need treatment for the underlying heart condition.

Usually, heart murmur treatment involves medications, surgery or both. Medications may include:

  • Angiotensin-converting enzyme (ACE) inhibitors like captopril (Capoten®) or benazepril (Lotensin®) to lower your blood pressure.
  • Beta-blockers like metoprolol (Lopressor®) or bisoprolol (Cardicor®) to reduce your heart rate and blood pressure.
  • Blood thinners like warfarin (Coumadin®) or aspirin (Bayer®, Zorprin®) to prevent blood from clotting in your heart.
  • Diuretics, or water pills, like furosemide (Lasix®) or torsemide (Demadex®). These rid your body of excess fluid that can make certain heart conditions worse.

If your heart condition is severe, you may need heart valve surgery or another procedure. Surgery options may include:

  • Valve repair: You may need a procedure to open a narrowed valve or tighten a leaky one.
  • Valve replacement: If a valve has narrowed severely, your cardiologist may replace it with a tissue or mechanical valve.
  • Open heart surgery: You may need an operation to repair an atrial or ventricular septal defect.


How can I prevent a systolic heart murmur?

There’s not a guaranteed way to prevent a systolic heart murmur. But you can increase your overall heart health by living a healthy lifestyle by:

Outlook / Prognosis

What is the outlook for a systolic heart murmur?

An innocent systolic murmur probably doesn’t need treatment. If you have an abnormal heart murmur, you may need treatment for a heart condition.

Fortunately, multiple treatments can help you live a healthier life with a heart condition. Practicing healthy habits can also help you improve your heart health.

Living With

What else should I ask my healthcare provider?

You may also want to ask your healthcare provider:

  • What is the most likely cause of a systolic heart murmur?
  • What diagnostic tests do I need?
  • Do I need treatment for a systolic murmur?
  • What treatment do I need for an underlying heart condition?
  • Would I benefit from seeing a specialist?
  • What lifestyle changes can improve my heart health?

A note from Cleveland Clinic

A systolic heart murmur is an unusual sound made when your heart contracts. Often, systolic heart murmurs are innocent, meaning they don’t point to any underlying heart problems. But sometimes a heart murmur is a sign of a heart condition. If you have an abnormal heart murmur, your healthcare provider can offer heart treatment. Healthy lifestyle habits can also help you live a more active life with a systolic heart murmur.

Last reviewed by a Cleveland Clinic medical professional on 06/16/2022.


  • Alpert MA. Systolic Murmurs. In: Walker HK, Hall WD, Hurst JW, eds. Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd edition. Boston: Butterworths; 1990. Accessed 6/16/2022.
  • American Heart Association. Heart Murmurs. ( Accessed 6/16/2022.
  • National Heart Foundation of New Zealand. What is a heart murmur? ( Accessed 6/16/2022.
  • National Heart, Lung, and Blood Institute. Heart Murmur. ( Accessed 6/16/2022.

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