A pacemaker is a small device that’s placed (implanted) in the chest to help control the heartbeat. It’s used to prevent the heart from beating too slowly. Implanting a pacemaker in the chest requires a surgical procedure. A pacemaker is also called a cardiac pacing device.

During an arrhythmia, the heart can beat too fast, too slow, or with an irregular rhythm. Pacemakers send electrical pulses to help your heart beat at a normal rate and rhythm. Pacemakers can also be used to help your heart chambers beat in sync so your heart can pump blood more efficiently to your body.