| 释义 |
EncyclopediaSeeSecond Soundsecond heart sound
sec·ond heart sound (S2), the second sound heard on auscultation of the heart; signifies the beginning of diastole and is due to closure of the semilunar valves. Synonym(s): second soundsecond heart sound Cardiology A heart sound that corresponds to closure of the semilunar–pulmonary and aortic valves, which is a short, higher pitched “dubb”. See First heart sound, Fourth heart sound, Third heart sound. sec·ond heart sound (S2) (sek'ŏnd hahrt sownd) The second sound heard on auscultation of the heart; signifies the beginning of diastole and is due to closure of the semilunar valves; auscultated at base of heart. |