S3 Heart Sound


S3 Heart Sound, S3 Gallop, S3 Gallup Rhythm, Third Heart Sound

  • Pathophysiology
  1. S3 sound represents rapid passive ventricular filling
    1. Occurs as ventricles start to expand during early diastole
  2. Outside of normal causes (see below), typically represents ventricular overfilling
    1. Associated with a dilated ventricle and Systolic Dysfunction
  • Signs
  1. S1, S2, S3 sound like "Ken-tuck-y" (lub-dub-dub)
  • Technique
  1. Best heard in left lateral decubitus position
  • Causes
  1. Normal
    1. Age under 40 years
    2. Third Trimester of pregnancy
  2. Left or Right Ventricle Volume Overload
    1. Mitral Regurgitation
    2. Tricuspid Regurgitation
    3. Congestive Heart Failure
  • Resources
  1. University of Michigan Heart Sound and Murmur Library
    1. http://www.med.umich.edu/lrc/psb/heartsounds/