Heart Sounds

15.3.3 Heart Sounds

The 4 heart sounds and 4 components are commonly abbreviated in discussions of cardiac auscultatory findings; numerical subscripts are used.

S₁ first heart sound

 M₁ mitral valve component

 T₁ tricuspid valve component

S₂ second heart sound

 A₂ aortic valve component

 P₂ pulmonic valve component

S₃ third heart sound

S₄ fourth heart sound

Examples:

The presence of an audible S₃was consistent with the patient’s ventricular aneurysm.

An audible S₄ may be due to a variety of cardiac and systemic conditions.

Sound names may be written out in full when discussed generically.

Third heart sounds are suggestive of congestive heart failure, but an S₃gallop may be a normal finding in children and young adults.

or:

The S₃ is suggestive of congestive heart failure, but an S₃ gallop may be a normal finding in children and young adults.

For plurals, follow the term with “sounds” or another noun.

S₃ sounds [not S₃s] may be normal or pathologic.

S₃ gallops may be a normal finding in children and young adults.