Arrhythmias are deviations from the normal rhythm or pattern of heartbeats which cause the heart to pump improperly. The heartbeat can be too slow, too fast, have extra beats, skip a beat, or otherwise beat irregularly.

The heart has four chambers or sections. Blood from the body enters the right auricle. It flows to the right ventricle. From there it is pumped out to the lungs where it picks up oxygen. The blood returns to the heart where it enters the left auricle, flows into the left ventricle, and is pumped out to the body where it gives up its oxygen to the cells. The blood then returns to the right auricle where it starts its travels over again. The sequence of contractions of the four chambers (the heartbeat) must be exact, otherwise the effectiveness of the pumping mechanism is decreased.

A normal heartbeat starts in the right...