The first heart sound (S1) results from the closing of the mitral and tricuspid valves. The sound produced by the closure of the mitral valve is termed M1, and the sound produced by closure of the ...

Heart sounds are the noises made when heart valves close as blood moves through the heart. S1 and S2 are normal heart sounds. Other heart sounds, such as S3 and S4, are abnormal. The heart has ...

The main normal heart sounds are the S1 and the S2 heart sound. The S3 can be normal, at times, but may be pathologic. A S4 heart sound is almost always pathologic. Heart sounds can be described ...