How does a pacemaker work?

A pacemaker system has two main parts: the generator and the lead (wire). The generator contains a computer that monitors your heart rhythm and controls when an electrical impulse is delivered to the heart. The battery of the pacemaker is contained in the generator. The lead is a long, thin wire that is connected to the generator at one end and is attached to the heart muscle on the other end.  The electrical impulse from the generator travels through this wire directly to the heart tissue.

The pacemaker is able to monitor your heart rhythm. When the heart’s own electrical system sends a signal and the heart beats, the pacemaker waits and does nothing. When the heart’s electrical system misses a beat, the pacemaker sends an electrical impulse to replace it.

The battery in a pacemaker can last between 8-12 years, depending on how much of the time your heart needs pacing.

Implanted pacemaker on x-ray



Single-chamber or dual-chamber pacing

Depending on the condition the pacemaker needs to fix, the doctor will either implant one (single –chamber) or two leads (dual – chamber) in the heart.  Leads will either be placed in the right atrium, right ventricle, or both.


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Implant Procedure