third heart sound


third heart sound (S3),

occurs in early diastole and corresponds with the end of the first phase of rapid ventricular filling; normal in children and younger people but abnormal in others. Synonym(s): third sound

third heart sound

S3 gallop, ventricular gallop Cardiology An extra heart sound traditionally regarded as a sign of left ventricular systolic dysfunction–heart failure; its significance differs according to the valve involved and the type of underlying defect; it is caused by rapid ventricular filling, and best heard over the apex with the Pt in supine or left lateral position; it ↑ with inspiration, exercise, elevation of legs, ↑ venous return. Cf Fourth heart sound.

third heart sound

(S3) (thĭrd hahrt sownd) Occurs in early diastole and corresponds with the end of the first phase of rapid ventricular filling; normal in children and younger people but abnormal in others.