S3 gallop


S3 gallop

Third heart sound Cardiology The heart sound that coincides with the onset of a low frequency diastolic wave generated by rapid filling; the SG is best heard at the apex of the left lateral decubitus position; the SG indicates ↓ ventricular compliance, and is characteristic of CHF; 'physiologic' SGs occur in children and young adults. See Congestive heart failure.