Heart Murmurs

When your heart beats, valves open and close, allowing blood to flow. When the valves close, they produce two sounds: a “lub” and a “dub.”

If your heart makes a whooshing or swishing sound instead, that’s called a heart murmur. A murmur means blood is flowing abnormally across your heart valves.

A murmur may mean there’s a problem with your heart. But heart murmurs are also present in healthy people who don’t have a heart problem (called “innocent” heart murmurs).

How common are heart murmurs?

Heart murmurs are quite common. In fact, most people had an innocent heart murmur at some point during childhood.

Are there different types of heart murmur?

Heart murmurs are classified based on when they happen in a heartbeat:

• Systolic: This type of murmur occurs when your heart muscle contracts (tightens).
• Diastolic: This type of murmur occurs when your heart muscle relaxes.
• Continuous: A continuous heart murmur happens during both contraction and relaxation of your heart muscle.

Diastolic and continuous murmurs are more likely related to heart disease. But every heart murmur should be evaluated.

How loud is a heart murmur?

You can’t hear a heart murmur with your ear. You need a stethoscope, which makes the sounds loud enough to hear.

Healthcare providers classify murmurs by how intense or loud they are. They use a scale of 1 (the murmur can barely be heard, even with a stethoscope) to 6 (it can be heard clearly, even when the stethoscope isn’t pressing on your skin).