S3 Heart Sound Page

Welcome to our S3 heart sound page. On this page we provide a definition and then we compare heart sounds with s3 to heart sounds with s4, using audio recordings and text. Finally, there is a link to the training lessons available on this site.

What is an S3 Heart Sound?

The third heart sound is a short, low frequency sound heard best with the stethoscope's bell. It occurs early in diastole and is dull in quality. As an extra heart sound, it creates a galloping rhythm with a cadence like word 'Kentucky'.

Normal vs S3 Heart Sound

Here we offer a comparison of a normal heart sound vs an S3 heart sound.

Compare normal to S3.

Normal

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Listen to this normal heart sound recording.

S3 Heart Sound

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Listen for a short, low frequency sound early in diastole. Try to match the cadence to 'Kentucky'.

S3 vs S4 Heart Sound

Compare S3 to S4 heart sounds using the audio tracks below.

S3 Heart Sound

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Listen for a short, low frequency sound early in diastole. Try to match the cadence to 'Kentucky'.

S4 Heart Sound

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Listen for a cadence like the word 'Tennessee' where the syllable 'Ten' is S4. S4 is usually short and low frequency.

Third Heart Sound Guide

Our auscultation guide provides information and examples of hearts sounds. For S3, the guide pages provide waveforms with a moving cursor that is synchronized to the audio recording. In addition, listening tips are available.
S3 Heart Sound

S3 Heart Sound Lesson

This is a link to our short course on extra heart sounds.
Extra Heart Sounds (S3 and S4)