What is a pacemaker? — A pacemaker is a device that sits under the skin near a person’s heart. A pacemaker can treat an abnormal heart rate. “Heart rate” is the term doctors use to describe how fast a person’s heart is beating.
Normally, each person has a built-in electrical system in the heart that controls his or her heart rate. A person’s heart needs to beat at a normal rate in order to pump blood to all parts of the body. Sometimes, a person’s built-in electrical system does not work the right way. This can cause a person’s heart to beat too slowly or too fast.
Different conditions, such as certain heart problems, can cause a person’s heart rate to be abnormal.
How does a pacemaker work? — A pacemaker sends electrical signals to the heart. These signals cause the heart to beat at a normal rate. Most of the time, pacemakers are used to treat a heart rate that is too slow. But pacemakers can also prevent or control a heart rate that is too fast.
Who might need a pacemaker? — A person might need a pacemaker if he or she has an abnormal heart rate and has symptoms. These symptoms can include:
- Feeling dizzy or light-headed
- Feeling your heart pounding
- Feeling confused or more tired than usual
- Trouble breathing
What does a pacemaker look like? — Most pacemakers have 2 parts:
- A “pulse generator” (picture 1) – This is a thin metal case with a battery and tiny computer in it. The pulse generator creates and sends electrical signals. A doctor can pre-set the computer to tell the pulse generator when to send electrical signals.
- Wires, also called “leads” – The wires connect the pulse generator to the heart. Electrical signals can travel from the pulse generator through the wires to the heart. Information about how the heart is working can also travel from the heart back to the pulse generator. There is one available pacemaker that works without any wires.
Do all pacemakers work the same way? — No. Pacemakers can work in different ways. A pacemaker can:
- Send electrical signals all of the time or some of the time – Some pacemakers send electrical signals at a steady rate all of the time. Others send electrical signals only when a person’s heart rate is too slow or too fast.
- Send electrical signals to one or more parts of the heart
What is a “temporary pacemaker”? — A temporary pacemaker is a pacemaker that is used for a short time, usually when a person is in the hospital. The pulse generator of a temporary pacemaker is not put inside the body. People might have a temporary pacemaker if they have a condition that will get better soon. They might also have a temporary pacemaker as a short-term treatment until they get a pacemaker put in their body.
What happens after I get a pacemaker? — After you get a pacemaker, you will need to follow up with your doctor on a regular basis. He or she might do a test called an “electrocardiogram” (ECG). An ECG measures the electrical activity in the heart. Your doctor will also check to make sure that your pacemaker is working the right way.
Some people might need to have the pulse generator part of their pacemaker replaced in the future. This is because the battery in the pulse generator usually lasts 5 to 8 years. Wires do not usually need to be replaced.
What else should I do if I have a pacemaker? — If you have a pacemaker, you will need to:
- Avoid certain electric or magnetic sources or equipment – Your doctor will tell you which electric or magnetic sources or equipment you can be near, and which ones you should avoid. For example, people with a pacemaker can be near televisions and radios. But some people with a pacemaker should not walk through a metal detector at the airport. (People who cannot walk through a metal detector can have a security search by hand instead.)
- Let all of your doctors and nurses know that you have a pacemaker – Some procedures and tests are safe for people with a pacemaker, but others are not. For example, people with a pacemaker should not have a type of imaging test called an MRI scan. Many people with a pacemaker carry an emergency medical card that tells people they have a pacemaker.
What is an implantable cardioverter-defibrillator? — An implantable cardioverter-defibrillator, also called an “ICD,” is a device that goes under a person’s skin near his or her heart (figure 1). An ICD can sense and treat certain abnormal heartbeats.
A person’s heart needs to beat normally in order to pump blood to the brain and rest of the body. But sometimes, a person’s heartbeat can suddenly become abnormal. The heartbeat could be too slow, too fast, or out of rhythm.
Some abnormal heartbeats are dangerous, because they can prevent the heart from pumping blood to the brain and rest of the body. A “cardiac arrest” is when an abnormal heartbeat prevents the heart from pumping blood normally. A cardiac arrest can happen without warning, and can cause death if it is not treated right away.
An ICD can treat the abnormal heartbeats that can lead to a cardiac arrest. People who have an ICD have a greater chance of surviving a cardiac arrest.
Who might need an ICD? — You might need an ICD if you:
- Have a condition that can cause abnormal heartbeats
- Have had one or more episodes of abnormal heartbeats
How does an ICD work? — An ICD works to:
- Sense abnormal heartbeats
- Give the heart one or more electrical shocks if the heartbeat becomes abnormal. This can get the heart to beat normally again.
- Record abnormal heartbeats so that a doctor can see how a person’s heart has been beating
What does an ICD look like? — An ICD has 2 parts:
- Battery (picture 1) – This sits under the skin. Depending on the type of ICD, it goes either in the upper chest or on the side, near the armpit. When the ICD senses an abnormal heartbeat, the battery creates an electrical shock or shocks that travel through wires to the heart.
- Wires, also called “leads” – In many ICDs, these go from the battery through a vein (blood vessel) and into the heart. There is also a newer type of ICD, which has wires that go near the heart but not actually inside it.
Can there be side effects to having an ICD? — Yes. Your doctor will talk with you about the different side effects that can occur. Side effects can occur when a doctor puts in an ICD. People who have had an ICD for a long time can also have side effects. But most people do not have any side effects from having an ICD.
What should I do after my ICD treats an abnormal heartbeat? — If your ICD gives you a shock (you will probably feel it), let your doctor know. He or she will look at the record of your heartbeats and might decide to make changes to the way your ICD works.
Do people with an ICD need other treatment? — Sometimes, people with an ICD will need other treatment. This can include medicines or procedures.
What if I want to get pregnant? — If you want to get pregnant, talk with your doctor or nurse. Many women with an ICD are able to have a baby.
What will my life be like? — Most people with an ICD have a normal life. But you will need to:
- Check your ICD on a regular basis to make sure that it works – Many people can check their ICD from their home, using either their phone or computer.
- Talk to your doctor about driving – Many states do not allow people to drive for some amount of time after they have an ICD put in or after they get a shock from their ICD. Your doctor will tell you how long you need to wait before you drive again.
- Avoid certain electric or magnetic sources – People who have an ICD need to avoid certain electric or magnetic sources or equipment. Your doctor will tell you which ones are safe for you to be near, and which ones you should avoid. For example, some people with an ICD should not walk through a metal detector at the airport. (People who cannot walk through a metal detector can have a security search by hand instead.)
- Let all of your doctors and nurses know that you have an ICD – Some procedures and tests are safe for people with an ICD, but others are not. For example, people with an ICD should not have a type of imaging test called an MRI scan. Most doctors recommend that people wear a medical bracelet letting others know that they have an ICD.
Some people who have an ICD feel worried or sad. If you feel worried or sad, let your doctor or nurse know so that he or she can help.