S1 and S2 are the normal heart sounds you hear when the heart valves close. Heart murmurs are extra sounds that can be heard during systole, diastole, or as a continuous sound. S3 and S4 are abnormal ...

An abnormal heart rhythm, or arrhythmia (also referred to as an irregular heartbeat), is a condition in which your heart beats too fast (at more than 100 beats per minute, or BPM), too slowly (at less ...