What Is a Heart Murmur?

Heart murmurs are common and often go unnoticed. In many cases, you may have a heart murmur and feel fine, with no noticeable heart-related symptoms at all. That’s why so many heart murmurs are discovered unexpectedly, during a routine physical, a pre-surgery examination or a visit for an unrelated concern.

While some murmurs are harmless and don’t affect heart health, others can signal a condition that deserves closer attention. Understanding what they are — and aren’t — can help you feel more informed and confident about next steps.

Defining Heart Murmurs

A heart murmur is an extra or unusual sound heard during a heartbeat. Instead of the typical “lub-dub” rhythm, a murmur may sound like a whooshing or swishing noise. Doctors usually hear murmurs through a stethoscope during a physical exam. A murmur itself isn’t a diagnosis, though. It’s simply a sound that signals how blood is flowing through the heart.

How the Heart Normally Works

Your heart has four chambers and four valves that work together to keep blood moving in the right direction. Each time your heart beats, the valves open and close to control blood flow.

When blood flows smoothly, your heartbeat sounds regular. But if it becomes turbulent — moving faster than normal or passing through a narrowed or leaky valve — a murmur may be heard.

Types of Heart Murmurs

Typically, doctors classify murmurs into two categories:

Innocent (Harmless) Heart Murmurs

An innocent heart murmur happens when the heart is healthy, but blood is flowing through it faster than usual. These types of murmurs are common and don’t require treatment.

Innocent murmurs are often heard in:

• Athletes with strong, efficient hearts
• Children and teens
• People who have a fever, anemia or thyroid conditions
• Pregnant women

Innocent murmurs can come and go, and they often disappear on their own. Innocent heart murmurs are so common in children and teenagers, in fact, that around one-third to three-quarters will have one at some point between the ages of 1 and 14, according to the American Heart Association.

Abnormal Heart Murmurs

An abnormal heart murmur may be linked to a heart problem — most often one involving the heart valves. You can have this type of murmur from birth, or you can develop it later in life.

If you have an abnormal heart murmur, your doctor will likely order more tests to determine the cause and whether you need treatment.

What Causes a Heart Murmur?

There are many possible causes of a heart murmur. Some are temporary, while others involve changes to the heart’s structure.

Common causes include:

• Age-related valve changes
• Conditions that increase blood flow, such as anemia or pregnancy
• Congenital heart conditions
• Heart valve problems, such as valves that are narrowed (called stenosis) or leaky (called regurgitation)
• Infections that affect the heart valves

In adults, murmurs are often related to heart valve disease, which becomes more common with age.

Heart Murmur Symptoms

Many people with heart murmurs have no symptoms at all, especially if the murmur is innocent.

When symptoms do occur, they may include:

• A bluish tint to the lips or fingertips (in infants and children)
• Chest discomfort
• Dizziness or fainting
• Fatigue or weakness
• Shortness of breath
• Swelling in the legs, ankles or feet

These symptoms don’t always mean you have a heart murmur, but you should always ask your doctor about them.

Diagnosing a Heart Murmur

Most often, doctors discover a heart murmur during a routine exam. If you learn you have a heart murmur, your doctor will likely schedule additional testing to understand what’s causing it.

Common diagnostic tests for a heart murmur may include:

• Blood tests
• Chest X-ray
• Echocardiogram (an ultrasound of the heart)
• Electrocardiogram (ECG, or sometimes referred to as an EKG)

These tests help determine whether a murmur is innocent or abnormal.

When to See a Doctor About a Heart Murmur

If you have a heart murmur with new or worsening symptoms, it’s important to seek care. But even if you have a heart murmur without symptoms, you should keep up with regular checkups, which can provide you with peace of mind and help protect your heart health.

Caring for Your Heart With Confidence

The initial discovery of a heart murmur always brings uncertainty, but it doesn’t have to bring fear. With proper evaluation and ongoing care, you can live a full, active life — even with a heart valve condition.

At AdventHealth, our heart and vascular specialists take a whole-person approach to care, supporting your body, mind and spirit at every step.

If you have a heart murmur that’s related to valve disease, our experts offer advanced diagnostics, monitoring and treatment options tailored to your needs. Learn more about heart valve disease care at AdventHealth.