What is a cardiac pacemaker?

A pacemaker is a small device that sits under the skin near a person's heart. It contains a generator and wires that help to control your heartbeat.

How does a cardiac pacemaker work?

A pacemaker sends electrical signals to your heart. These signals cause the heart to beat at a normal rate. There are two main parts to the pacemaker:

  • Pulse generator — this small metal case contains a battery and tiny computer inside which send electrical signals to regulate your heart.
  • Wires, also called “leads” — the wires connect the pulse generator to the heart, electrical signals travel from the pulse generator through the wires and to your heart to adjust your heartrate.

Common conditions that could require a cardiac pacemaker

Most of the time, pacemakers are used to treat a heart rate that is too slow (bradycardia). But pacemakers can also prevent or control a heart rate that is too fast. Symptoms along with irregular heartbeat that can cause the need for a pacemaker are:

  • Fainting
  • Feeling dizzy or light-headed
  • Trouble breathing
  • Feeling more confused or tried than normal

Are all pacemakers the same?

No. Pacemakers can work in different ways depending on the person. Three most common types of pacemakers are:

  • Single chamber pacemaker — this type of pacemaker usually carries electrical impulses from the pulse generator to the right ventricle of your heart.
  • Dual chamber pacemaker — dual chamber pacemakers carry electrical impulses to both the right ventricle and right atrium of your heart.
  • Biventricular pacemaker — unlike a regular pacemaker, this type of pacemaker stimulates both the left and right ventricles of the heart to make the heart beat more efficiently.

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