Heartbeat Sound Lub Dub | 2025 |

The "lub-dub" sound is the sound of the heartbeat, which is produced by the closing of the heart valves. The sound is created by two distinct sounds:

A sharper, higher-pitched, shorter snap. Think Dub . What is happening: The Semilunar valves are closing. heartbeat sound lub dub

That longer pause after the "Dub" is when your heart muscle is resting and refilling with blood. It is the most important rest in the body. The "lub-dub" sound is the sound of the

Shorter, higher, softer, at the start of diastole (relaxation). Clinical Significance heartbeat sound lub dub

A low, slightly prolonged sound. Think Luuub . What is happening: The atrioventricular (AV) valves are closing.

A higher-pitched, shorter sound marking the start of diastole. It is produced when the semilunar valves (aortic and pulmonary) close. Summary of Differences