What are pacemakers?
Pacemakers are small medical devices that are implanted into the chest to regulate abnormal heart rhythms (arrhythmias) using electrical impulses.
The parts of a pacemaker
A pacemaker consists of a pulse generator, leads, and electrodes.
Pulse generator
The pulse generator is the battery-powered device that generates electrical impulses. It is typically implanted under the skin near the collarbone and contains the battery and electronic circuitry.
Leads
The leads are insulated wires that carry electrical impulses from the pulse generator to the heart. They are placed in specific chambers of the heart (atrium, ventricle, or both).
Electrodes
The electrodes are located at the end of the leads and make contact with the heart tissue.
Types of pacemakers
Single-chamber pacemaker
In single-chamber pacemakers, one lead is placed in either the right atrium or the right ventricle. This type is used when only one chamber of the heart needs pacing.
Dual-chamber pacemaker
Dual-chamber pacemakers have one lead placed in the right atrium and a second lead placed in the right ventricle. This helps coordinate the timing between the atrium and ventricle, mimicking natural heart rhythm.
Biventricular pacemaker
Biventricular pacemakers are used for cardiac resynchronization therapy. Leads are placed in the right atrium, right ventricle, and left ventricle.
This is indicated for clients with heart failure to improve the coordination of the heart’s contractions.
Leadless pacemaker
Other than traditional pacemakers, leadless pacemakers are contained within a single capsule directly in the right ventricle.
How do pacemakers work?
After a pacemaker is implanted, it monitors the heart’s electrical activity continuously. When it detects arrhythmia or a pause, the device sends electrical impulses to stimulate the heart and prompt it to beat at a normal rate.
Restoring the normal heart rhythm can alleviate symptoms (such as fatigue, dizziness, fainting), reduces the risk of complications, and improves quality of life and exercise capability.
Here’s a summary of the functions of pacemakers:
- Regulate heart rate: stimulates heart to beat at normal rate and rhythm and keeps the heart rate from dropping too low
- Coordinate heart chambers: ensures proper timing between the contractions of the atria and ventricles and improves the heart’s efficiency
- Treat heart failure: synchronized the contractions of the left and right ventricles to improve cardiac output (cardiac resynchronization therapy)
Indications
- Bradycardia
- Heart block
- Atrial fibrillation
- Heart failure (sometimes)
Risks
Immediate complications:
- Infection at implantation site
- Allergic reaction to device material
- Bleeding or hematoma
- Lead dislodgement or malfunction
- Pneumothorax
Long-term complications:
- Lead failure
- Battery depletion
- Device malfunction (suboptimal pacing)
- Thromboembolism
Common questions
Why do AED pads need to be placed one inch away from jewelry or pacemakers?
When using automated external defibrillators (AEDs), the pads delivering the shocks need to be placed away from jewelry or pacemakers to prevent electrical interference that could happen when the pads are too close to metal objects and implanted devices.
How long do pacemakers last?
Pacemakers can typically last between 5 and 15 years. Battery life and device function are monitored in regular check-ups.
How much do pacemakers cost?
While highly variable, the average cost for getting a pacemaker can range from $20,000 to $50,000 in the US.
How many people have pacemakers?
Each year, about 600,000 new pacemakers are implanted. As the average population age worldwide is increasing and the technology is improving, pacemakers are becoming more prevalent.
How do pacemakers charge?
Pacemakers do not need to be charged. Pacemakers have internal batteries that typically last several years, and when they are depleted, the pacemaker needs to be replaced. Newer technologies that address this are still in development.
