S1 is the first heart sound that doctors can hear using a stethoscope. The vibrations that occur when the mitral and tricuspid valves in the heart close produce the S1 sound. There are two common ...

An S4 heart sound is a low-pitched sound that occurs toward the end of the diastole. In some cases, an underlying health condition, often one affecting the left ventricle, may cause the S4 heart sound ...

Heart sounds are produced from a specific cardiac event such as closure of a valve or tensing of a chordae tendineae. Many pathologic cardiac conditions can be diagnosed by auscultation of the heart ...

The second heart sound (S2) is produced by the closure of the aortic and pulmonic valves. The sound produced by the closure of the aortic valve is termed A2, and the sound produced by the closure of ...

IT IS possible that the existence of the heart sounds was known to Hippocrates 1 and even that he made use of his knowledge for diagnostic purposes, but William Harvey 2 seems to have been the first ...