Exam

S3 Heart Sound

search

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

  • See Also
  1. Heart Auscultation
  2. S1 Heart Sound
  3. S2 Heart Sound
  4. S4 Heart Sound
  5. Heart Murmur
  6. Pediatric Murmur
  • 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)
  2. Left Ventricular S3
    1. Heard best at apex, with patient in left lateral decubitus position, during expiration (breath held)
    2. Accentuated with isometric hand grip
  3. Right Ventricular S3
    1. Heard best at the left sternal border, with patient supine, during inspiration
    2. Accentuated with passive leg raise
    3. May be associated with Jugular Venous Distention
  • Causes
  1. Normal
    1. Age under 40 years (esp. children and young adults)
    2. Third Trimester of pregnancy
  2. Left or Right Ventricle Volume Overload
    1. Mitral Regurgitation
    2. Tricuspid Regurgitation
    3. Congestive Heart Failure
    4. Ventricular Septal Defect
    5. Patent Ductus Arteriosus
    6. Constrictive Pericarditis
  3. Hyperkinetic cardiac activity
    1. Thyrotoxicosis
    2. Anemia
    3. Chronic Thiamine deficiency (Beriberi)
  • Resources
  1. University of Michigan Heart Sound and Murmur Library
    1. http://www.med.umich.edu/lrc/psb/heartsounds/
  2. Silverman in Walker (1990) The Third Heart Sound, Clinical Methods, 3rd ed
    1. https://www.ncbi.nlm.nih.gov/books/NBK342/