How Does a Pacemaker Work?

The body generates electrical impulses that cause the heart to beat. In some people, those electrical impulses don't happen in a normal pattern, which can cause the heart to beat too slowly, too fast or irregularly. A very slow heartbeat can lead to fatigue, lightheadedness, dizziness and fainting. In patients who are at risk for a very slow heart rate, doctors often recommend a pacemaker.

Disorders in the heart's electrical system can lead to arrhythmias, or an abnormal heart rhythm. Some patients who have been diagnosed with a slow heart rate, known as bradycardia, may require a pacemaker. A pacemaker is a device that is implanted in the chest and can correct a slow heartbeat.