What Are Pacemakers?
Reviewed by: HU Medical Review Board | Last reviewed: June 2023
A pacemaker is a small battery-powered device designed to help the heartbeat in a regular rhythm.1-4 It is an effective tool in the management of heart rhythm disorders. A healthy heart has its own natural pacemaker. If heart failure, a heart attack, or other cardiac condition causes a change in the heart’s rhythm, resulting in a beat that is too fast (tachycardia) or too slow (bradycardia), or irregular (arrhythmia) - the electrical impulse from the pacemaker can restore a more normal heartbeat, helping it to beat more regularly.4
The purpose of a pacemaker is to monitor the heart rate and to send electrical impulses to the right atrium or right ventricle of the heart to start each heartbeat when it is needed.1 A pacemaker is made up of a computer and battery - usually called a generator, and coated wires called leads. You can have up to three flexible electrode leads.1,4 The pacemaker produces electrical impulses that regulate the heartbeat.4 The impulses flow through the wires to the heart. The pacemaker is programmed to provide pace your heart at regular intervals just like your normal heartbeat.4
Pacemaker inserted surgically
A pacemaker is commonly inserted surgically through a small incision just below the collarbone. A small pocket is created between the skin and the chest muscle.1,4 The cardiologist guides the attached wires to position them through the vein leading into the heart.1,3-4 It is a procedure that usually takes under an hour and is carried out under local anesthesia.1,4 Your doctor will set your pacing rate by determining the amount of electrical energy required to stimulate the heart.1
There may be some limited pain or discomfort after the procedure, but it should resolve within a few days. In order to ensure that the leads do not move after implant, there are restrictions on activities and exercise for about 5 weeks. You cannot lift your arm above your shoulder, lift anything heavy, or perform activities that would place a strain on or near the surgical site.1,3
How does the pacemaker work?
The heart has a natural pacemaker called the sinoatrial (SA) node. The SA node is a group of specialized cells at the top of the right atrium which produces the electrical impulses that stimulate each heartbeat.4 If there is damage to the natural pacemaker the normal heartbeat may be disrupted. An artificial pacemaker uses its generator to send electrical impulses to the heart. The attached wires placed alongside the heart wall send small electrical signals through the wire to the heart to help it pump effectively.4
As pacemakers typically monitor your heartbeat they can sense when the heartbeat is functioning at a sufficient level. It tells the pacemaker to send an impulse when the heartbeat is too slow.4
A pacemaker can be used temporarily or permanently. The determination is based on the damage to the heart’s electrical system.1 A temporary pacemaker may be required after a heart attack while you are hospitalized if the heart rhythm is too slow. A temporary pacemaker is external to the chest and is not surgically inserted. If the heart's electrical system can resume a normal rate and rhythm, the pacemaker may not be needed on an ongoing basis and is removed.2
What you need to know
Each pacemaker is evaluated to see how well it is working. This is done by using a wand that can transmit information that is stored in the device’s generator to an external computer. The information includes the battery life, the condition of the leads, and any abnormal rhythms that have occurred since the pacemaker was inserted.3
Always let your healthcare team know that you have a pacemaker. Some medical or dental procedures may require precautionary measures.1 You may even set off a metal detector alarm or two, even at the airport.
You should carry a pacemaker ID card in your wallet. It lists important personal information including the type of pacemaker, manufacturer, make, model and serial number. It also lists the date of implantation, your individual pacing rate, and emergency contact information. These ID cards are available in different forms including ones that can be downloaded for free from the internet.4