How to auscultate for S3 or S4 ?
- S3 or S4 is best heard at the cardiac apex with the bell of stethoscope placed lightly.
- Sometimes, they are best heard with the patient turned to left lateral position
- Often they are better felt than heard.
- They are low-pitched sounds.
- Left-sided S3 (LVF) is best audible at the apex during expiration while the right-sided S3 (RVF) is best heard at the lower left sternal border during inspiration.
- Handshould be placed very lightly over the skin. More pressure will tighten the skin and smother the low-frequency sounds.
It is made for listening low-pitched sounds like.
- Murmur of MS and TS.
- S3 or S4.
- Foetal heart sounds.
- Venous hum.
