second heart sound


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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 sound

second 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.
References in periodicals archive ?
ASDs are typically uncovered on exam via auscultation of heart sounds, which might reveal a split of the second heart sound (S2) and diastolic murmurs.
On auscultation second heart sound was loud in pulmonary area with narrow split, ejection systolic murmur heard in the pulmonary area.
Auscultation revealed a first and second heart sound with no added sounds or murmurs and normal breath sounds.
Heart sounds comprise two main components: the first heart sound (S1), and the second heart sound (S2).
A crunching sound together with the second heart sound was heard predominantly in the mesocardiac area.
His second heart sound (S2) occurred with physiological split.
Children are likely to be hypoxemic and tachypneic, run a fever, and have abnormal breath sounds and increased second heart sound.
The paradoxically split second heart sound predicts left bundle branch block (LBBB).
In cardiac auscultation, the heart sounds were heard at the right of sternum and there was splitting in second heart sound (S2).
A loud, single second heart sound was audible and no murmur was present.
Precordial examination demonstrated a parasternal heave and a loud second heart sound.