Authors: Grace Wu and Jasmine Wang
Date Published: October 2, 2025
If you have ever taken a first aid course before, you have probably heard of a pacemaker. It is a device that is transplanted into the body of a person whose heart beats at a different speed or rhythm compared to an average human heart. This article will delve into the basics of what a pacemaker is, why they are used, and different types of pacemakers.
What is a pacemaker and why is it needed?
A pacemaker, or cardiac pacing device, is a small battery-powered device used to manually regulate heart beat. It is surgically implanted under the skin near the collarbone and sends electric impulses to the heart.
A pacemaker usually has two components: a pulse generator and leads. The pulse generator is a small metal box with a battery and electrical parts that creates the electrical impulses and controls the rate at which they are sent to the heart. The leads are flexible wires that run from the pulse generator to the heart’s chambers. They are what send the electrical impulses into the heart.
Currently, there are also pacemakers without leads, or leadless pacemakers, where the pulse generator and electrodes are combined into one device which is implanted directly into the heart.
Pacemakers are used to treat heart conditions such as…
Bradycardia, when the heart beats to slowly
Tachycardia, when the heart beats too fast
Arrhythmias, when the heart beats abnormally, such as in blocks or with skipped beats
Cardiomyopathy, when the heart is weak, and its beats are not strong enough to efficiently push blood around the body
Different types of pacemakers:
There are three main types of pacemakers:
Single-chamber pacemaker: This type of pacemaker affects a single chamber of the heart. Usually, it is connected to the lower right chamber, or the right ventricle, though it may also be connected to the upper right chamber, known as the right atrium, depending on the person’s symptoms and needs.
Dual-chamber pacemaker: This type sends electrical impulses to two chambers of the heart, both the upper and lower right heart chambers. This allows for the contractions between the heart chambers to be controlled, allowing blood to properly flow from the lower to the upper chamber. The need for this type is dependant on the specific pacing needs of the person.
Biventricular pacemaker: Also called a cardiac resynchronization pacemaker, this type sends electrical impulses to both of the lower left and right heart chambers. It is used by people who have a slow heartbeat, usually as a result of heart failure. The device stimulates both lower heart chambers. It helps make the heart muscle stronger.
Works Cited:
Foundation, B. H. (2024, June 19). Pacemakers. British Heart Foundation. https://www.bhf.org.uk/informationsupport/treatments/pacemakers
Health Care, S. (2025). Pacemaker. Stanford Medicine Health Care. https://stanfordhealthcare.org/medical-treatments/p/pacemaker.html
Staff, M. C. (2025, June 4). Pacemaker. Mayo Clinic. https://www.mayoclinic.org/tests-procedures/pacemaker/about/pac-20384689
Sy, P. (2025, July 9). Pacemakers: Surgery, types and how they work for heart health | U.S. news. U.S. News & World Report. https://health.usnews.com/health-care/conditions/articles/pacemakers-surgery-types-and-how-they-work-for-heart-health