A pacemaker is an implantable electronic device that prevents the heart from beating too slowly, below a preset baseline frequency. It draws energy from a small, hermetically sealed battery inside and remains inactive until the heart rate falls below the defined threshold. When this occurs, it activates and delivers small electrical impulses to the heart, forcing it to “beat.”
The pacemaker may have one, two, or in some cases, three leads (electrodes) that send and receive impulses to and from the heart.
The pacemaker will be programmed, monitored, and periodically reprogrammed (if necessary) to meet your needs. This is usually done during appointments at the outpatient cardiology clinic, where your doctor, using an external device-computer, will check and adjust your device. The pacemaker’s battery status will be checked at every appointment, and the remaining battery life will be calculated. The battery does not recharge and typically lasts 6-8 years. When it needs to be replaced, the entire pacemaker is swapped out, using a procedure similar to the initial implantation.
Types of Pacemakers:
- Single-chamber: Has one electrode placed in the right upper (right atrium) or right lower (right ventricle) heart chamber.
- Dual-chamber: Has two electrodes, one in the right upper (right atrium) heart chamber and one in the right lower (right ventricle) heart chamber.
- Biventricular: Has three electrodes, one in the right upper heart chamber (right atrium), one in the right lower heart chamber (right ventricle), and one in a coronary vein (usually the lateral vein), to pace the left ventricle. This type is used in special cases with severe heart failure and specific conduction disturbances within the ventricles.
Your doctor will decide which type of pacemaker is best suited for your condition and health needs.