Patient education: Heart murmurs (The Basics)

What is a heart murmur? — A heart murmur is an extra sound that doctors or nurses hear when they listen to the heart with a stethoscope. A heart murmur usually sounds like an extra "whoosh" or "swish" in the heartbeat.

Normal heart sounds are made as the heart valves close and blood flows through the heart (figure 1). The heart valves are structures that keep blood flowing in only 1 direction. They work like swinging doors that open only 1 way – letting blood out, but not back in.

A heart murmur happens when the sound of blood flowing through the heart or blood vessels is loud enough to be heard. This can happen when the heart is normal. It can also happen when there is a heart condition that changes the way the heart valves work or the way blood flows through the heart or blood vessels.

How do I know if I have a heart murmur? — Most people learn that they have a heart murmur during a routine exam. If your doctor or nurse hears a heart murmur, they might have you hold your breath or change your position while they listen to your heart. This will tell the doctor or nurse more about your heart murmur.

Does having a heart murmur mean that I have a heart problem? — Not always. People with normal hearts and blood vessels can have heart murmurs. Doctors call these "innocent" heart murmurs. Innocent heart murmurs are not caused by a heart problem.

People of any age can have an innocent heart murmur. But innocent heart murmurs are especially easy to hear in people who are young, thin, or pregnant.

Other heart murmurs are abnormal. These are caused by a heart condition. Common causes of abnormal heart murmurs are:

●Problems with the heart valves – The heart valves can leak too much and let blood flow backward. Or they can get stuck and not open well.

●Other heart problems, such as a hole in one of the walls inside the heart

Will I need tests? — Maybe. When your doctor or nurse first hears a heart murmur, they will want to know if it is innocent or abnormal. They will ask you questions and do an exam.

If your heart murmur is innocent, you will not need any tests.

If your doctor or nurse thinks your heart murmur might be abnormal or isn't sure, they might order a test to find out what is causing the murmur. The test most commonly used is an echocardiogram (also called an "echo"). This test uses sound waves to create a picture of your heart as it beats. It shows the size of the heart chambers, how well the heart is pumping, and how well the heart valves are working (figure 2).

How is an abnormal heart murmur treated? — The treatment depends on the heart condition that is causing the abnormal murmur. It also depends on how serious the condition is. If your heart condition is not serious, you might not need any treatment. But your doctor will follow your condition to see if it changes or gets worse.

If your heart condition is serious, you might need treatment. Treatment might involve surgery or a procedure that uses a thin tube called a "catheter" to reach the heart.

Do I need to take antibiotics before I go to the dentist? — Ask your doctor. In the past, doctors recommended that many people with a heart murmur take antibiotics before having certain dental or medical procedures. But now, only people with certain heart conditions need antibiotics before dental or medical procedures. Ask your doctor if you need antibiotics for those times.

More on this topic

Patient education: Echocardiogram (The Basics)
Patient education: Mitral regurgitation (The Basics)
Patient education: Aortic stenosis (The Basics)
Patient education: Mitral stenosis in adults (The Basics)
Patient education: Mitral valve prolapse (The Basics)
Patient education: Tricuspid regurgitation (The Basics)
Patient education: Tricuspid stenosis (The Basics)
Patient education: Vagal maneuvers (The Basics)
Patient education: Aortic regurgitation in adults (The Basics)

Patient education: Mitral regurgitation (Beyond the Basics)