S1

  closure of mitral and tricuspid valves

  soft if long PR or mitral regurgitation

  loud in mitral stenosis

Wide splitting of S1 that is accentuated by inspiration is a sign of delayed closure of the tricuspid valve. This condition can occur in patients with complete RBBB or tricuspid stenosis.

S2

 closure of aortic and pulmonary valves

 soft in aortic stenosis

 splitting during inspiration is normal

Gallop Heart Sounds

S3 (splash) - ventricular gallop sound (after S2)

  caused by diastolic filling of the ventricle with tense papillary chordal apparatus (reduced intrinsic ventricular wall compliance)

It can occur in the following conditions:

• forceful, rapid filling of a ventricle that has normal or elevated compliance during diastole
• Normal or even decreased filling rates when ventricular compliance is low
• Blood flowing into an overfilled ventricle with high end-systolic volume

In short, suspect DILATED LEFT VENTRICLE

(best heard with the bell [low pitch] at the apex area while the patient is in the left lateral decubitus position at the end of expiration)

heard in left ventricular failure, restrictive cardiomyopathy and MR (high output states)

N.B.