Pacemakers are commonly used to treat several forms of arrhythmia. A pacemaker is a battery-powered device that is inserted under the skin (or sometimes under the muscle), usually near the collarbone. It is attached to the heart via one or more wires (leads) that extend from the pacemaker through the veins to the right side of the heart.
The pacemaker monitors the heartbeat. If the heart rate is normal it stays off; however, if the beat is too slow, fast or erratic, the pacemaker sends a mild electrical signal to the heart that causes it to beat at a more beneficial pace. For patients who have had an AV node ablation, the pacemaker is required to keep the heart beating.
A similar device called a biventricular pacemaker can be used to treat some arrhythmia issues caused by heart failure.