A pacemaker is a small device that’s placed under the skin in your chest to help control your heartbeat. It’s used to help your heart beat more regularly if you have an irregular heartbeat (arrhythmia), particularly a slow one. Implanting a pacemaker in your chest requires a surgical procedure.

A pacemaker may be inserted in order to stimulate a faster heart rate when the heart is beating too slowly, and causing problems that cannot otherwise be corrected.

Types of pacemakers

Depending on your condition, you might have one of the following types of pacemakers.

  • Single chamber pacemaker.This type usually carries electrical impulses to the right ventricle of your heart.
  • Dual chamber pacemaker.This type carries electrical impulses to the right ventricle and the right atrium of your heart to help control the timing of contractions between the two chambers.
  • Biventricular pacemaker.Biventricular pacing, also called cardiac resynchronization therapy, is for people with heart failure with abnormal electrical systems. This type of pacemaker stimulates the lower chambers of the heart (the right and left ventricles) to make the heart beat more efficiently.

Pacemakers work only when needed. If your heartbeat is too slow (bradycardia), the pacemaker sends electrical signals to your heart to correct the beat.

Also, newer pacemakers have sensors that detect body motion or breathing rate, which signal the pacemakers to increase heart rate during exercise, as needed.