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 ...

A third heart sound, or S3, is a low-frequency, extra heart sound that may be heard with a stethoscope right after the normal S1 and S2 heart sounds. S1 and S2 are the "lub-dub" sounds of a ...

Many people have experienced the strange sensation of hearing their heartbeat while lying in bed. For some, this rhythmic ...

A S4 heart sound can be an important sign of diastolic heart failure or active ischemia and is rarely a normal finding. Diastolic heart failure frequently results from severe left ventricular ...