A site for medical students - Practical,Theory,Osce Notes

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.