About Pacemakers

You have been recommended to have a pacemaker implant to treat your heart rhythm problem. The purpose of this guide is t o help you and your family prepare for this procedure and for your recovery at home.

The Heart's Electrical System

Your heart is a muscle that works like a pump. The main job of your heart is to pump blood throughout your body. The heart is divided into a right and left side. Each side has an upper chamber, or atrium, that collects blood returning to the heart and a muscular lower chamber, or ventricle, that pumps the blood away from the heart.

The pumping of your heart is regulated by an electrical current, or impulse, much like a spark plug in a car. The electrical impulse starts in the sinoatrial (SA) node, often called the body’s natural pacemaker, and then spreads throughout both atria, like ripples in a pond. This c auses both atria to contract, squeezing blood into the ventricles.

The impulse then travels down to the atrioventricular (AV) node, which is like a wire that connects to the ventricles. The AV node splits into two branches, allowing the even spread of the electrical signal to both ventricles at the same time. This lets your heart beat effectively.

Medical illustration of a heart showing the left and right atria, which collect blood returning to the heart, and the left and right ventricles, which pump the blood away from the heart.

Heart Arrhythmias

Medical illustration of a heart showing the sinoatrial node, the atrioventricular node, and the His-Purkinjie fibres, which control the electrical impulse that causes your heart to pump.

Arrhythmias are an abnormality of the heart’s electrical system. Tachyarrhythmia occurs when the heart beats too fast. Bradyarrhythmia occurs when the heart beats too slowly.

Arrhythmias are very common and usually do not cause problems; however, in rare cases, they can cause you to have symptoms such as dizziness or extreme tiredness.

Why a Pacemaker Is Necessary

Most patients need a pacemaker because their hearts beat too slowly to meet the needs of their bodies. This is known as bradycardia. A slow heart rate can cause symptoms such as dizziness, fatigue or fainting spells that can put you at risk of injury or harm.

Parts of a Pacemaker

There are several different types of pacemakers, each of which has different capabilities. The decision about which pacemaker to implant is based on your particular situation.

In general, pacemakers are made up of two basic parts: the pacemaker generator (sometimes called the battery) and one or more wires called leads.

The generator contains the battery, important wiring and computer components that make the pacemaker work properly. The leads are special wires that are connected on one end to the generator, with the other end attached to a spot inside your heart.

To help your heart beat properly, a very small pulse of electricity is transmitted from the generator and travels along the leads directly into the heart muscle. This electrical current makes the heart beat and can be delivered as needed to keep your heart beating at a healthy rate.

Illustration of a heart and a cardiac resynchronization device, showing the generator and the electrical leads inserted into the heart.

In general, pacemakers are implanted on the left side of the chest, just beneath the collarbone.

Depending on which pacemaker is implanted, expect to receive an information booklet in the mail from the company that made your device. This booklet will have extra information about your specific pacemaker.

Cardiac Resynchronization Therapy

A cardiac resynchronization (CRT) device is a specialized pacemaker designed for people with heart failure. It is designed to coordinate both sides of the heart to help it beat more efficiently. CRT devices are usually only used for people with certain types of heart failure.