The American Heart Association has prepared this booklet to answer your questions and help you lead a full, productive life. If you still have questions after reading this, ask your doctor to answer them.

Your artificial pacemaker is a modern marvel; it's medical science's solution to the electrical problems of a slow heartbeat. But before you can understand how your pacemaker works, you first need to know a little about your heart.

Basically, your heart is a pump made of special muscle. It pumps blood to all your body's cells. This is vital, because the blood carries oxygen and nourishment to keep your cells alive and healthy.

Your heart beats (pumps blood) because special cells in your heart (the heart's natural pacemaker, called the sinus node) produces electrical impulses. These cause your heart to contract and pump blood. The impulses travel from the pacemaker cells down certain electrical paths in the muscle walls, causing a contraction.

As long as the electrical impulses flow down your heart's walls at regular intervals, your heart pumps at a rhythmic pace. Sometimes, though, something happens to interfere with how the electrical impulses of the heart's natural pacemaker are made or flow down your heart. When this occurs, the natural pacemaker can't do its job as well as it needs to.

Problems that change the heart rhythm include…

1. A complete block of the heart's electrical pathway.

2. A slow beat.

3. An irregular rhythm.

If you have a slow and often irregular heartbeat, or if your heartbeat is sometimes normal and sometimes too fast or too slow, blood isn't pumped around your body well. In that case your doctor may recommend an artificial pacemaker. A pacemaker will make your heart beat more regularly. That will help ensure that enough oxygen and nourishment get to your body's cells.

An artificial pacemaker system has two parts: a generator and wires (leads). The pacemaker generator is a small battery-powered unit. It produces the electrical impulses that start your heartbeat. The generator is implanted under your skin through a small incision.

The generator is connected to your heart through tiny wires that are implanted at the same time. The impulses flow through these leads to your heart and are timed to flow at regular intervals just as impulses from your heart's natural pacemaker would.

Modern pacemakers last much longer than earlier models. As with any electronic device, your artificial pacemaker will require some care. The batteries, for example, will wear down over time and the pacemaker will need to be replaced. This is a minor surgical procedure. Your healthcare provider can explain it to you.

As the batteries wear down, your pacemaker will slow down, but it won't stop right away. Using a special analyzer, your doctor can detect the first warning that the batteries are running down. This can be done before you can detect any changes yourself. A sudden, major slowing down of your heart rate, which you may detect, probably indicates a more serious problem. If that occurs, call your doctor.

If you have a pacemaker, you'll have to learn to do certain things (or else have someone help you). A discussion of them follows.

Take your pulse and keep a record for your doctor.

Counting your pulse is a good way to check that your heart is pumping correctly. Every time your heat beats, it pumps blood through your blood vessels. By putting your fingertip on a point on the inside of your wrist or over an artery in your neck you can feel this beat (pulse). The number of pulsebeats per minute is the same as the number of heartbeats. Count your pulse for one full minute; note the number beats and see if it's below the acceptable range for your pacemaker. Your doctor can tell you how many times your heart should beat per minute. Write down this information. If your pulse is very slow or very fast, call your doctor.

Most pacemakers work only when they're needed. They're called demand pacemakers. Demand pacemakers have a sensing device that shuts them off if the heartbeat is above a certain rate. When the heart is beating slower than the pacemaker rate, the sensing device turns the pacemaker on again. In this way, a demand pacemaker works something like a thermostat. The difference is that instead of working according to temperature, it works according to your heart rate.

Here are some guidelines for pacemakers and pulse counts:

1. If your pacemaker is beating regularly and at or above its proper rate, it's OK. You can't tell which pulse is started by your heart's natural pacemaker or the artificial pacemaker.

2. If your heart is beating close to or within the accepted rate but has an occasional irregularity, don't worry. Every now and then your own heart's natural pacemaker competes with the man-made one. Some extra beats that the pacemaker can sense electrically won't result in a pulse that you can feel.

3. If your pulse rate suddenly drops below the accepted rate or increases dramatically, call your doctor immediately. Your doctor will tell you what to do. It may be possible to program your pacemaker so it resumes working normally, or there may be some other problem.

4. If your pulse is beating faster than you've noticed before - but below 100 - don't be alarmed. Before you leave the hospital, discuss with your doctor the specific maximum heart rate above your pacemaker rate that's acceptable. Discuss the programmed lower and upper rate for your pacemaker, too. Talking about this with your doctor early in your treatment will keep you from worrying unnecessarily.

Take medications as prescribed.

It's important to follow instructions and take prescribed medicine. The reason is that the medicine works with the pacemaker and helps your heart pump regularly. Your doctor may ask you to keep a record of when you take your medication by marking a calendar.

Follow all instructions regarding diet and physical activity.

Allow about eight weeks for your pacemaker to settle firmly in place. During this time, avoid sudden, jerky or violent actions that will cause your arm to pull away from your body.

Other warnings and Information

1. Avoid causing pressure over the area of your chest where your pacemaker was put in. Women may find it more comfortable to wear a small pad over the incision as protection from their bra strap. Feel free to take baths and showers. Your pacemaker is completely protected against contact with water.

2. Follow the program of activity outlined by your doctor. Car, train or airplane trips pose no danger. People with pacemakers also can continue their usual sexual activity.

3. Perform some kind of physical activity every day, whatever kind you enjoy. You might try taking a short walk, or moving your arms and legs to help your circulation. If you're not sure about exercising, ask your doctor for advice. You may be able to perform all normal activities for a person of your age.

4. Don't overdo it - quit before you get tired. The proper amount of activity should make you feel better, not worse.

Report to your doctor if…

1. You have difficulty breathing.

2. You begin to gain weight and your legs and ankles swell.

3. You faint, blackout or have dizzy spells.

Many doctors follow-up with patients by monitoring how well their pacemaker is working.

Tell physicians, dentists and other health professionals that you have a pacemaker.

Physicians or dentists that you visit need to know that you have a pacemaker. Tell them about it before you have any work done. Notify the doctor or nurse where you work. Modern pacemakers have built-in features to protect them from most types of interference produced by other electrical devices you might encounter in your daily routine. Household appliances such as microwave ovens, televisions, radios, stereos, vacuum cleaners, electric brooms, electric blankets, electric knives, hair dryers, shavers, gardening machinery, toasters, food processors, and can openers won't affect your pacemaker. Most office and light shop equipment such as computers, typewriters, copy machines, woodworking shop tools,, and metalworking tools also pose no risk to your pacemaker.

If you suspect interference with your pacemaker, simply move away or turn off the equipment. Your pacemaker won't be permanently damaged and will resume its normal activity. Consult your doctor about special situations (such as working with high-current industrial equipment and powerful magnets). Surgical procedures also count as special situations. Certain types of medical equipment, such as magnetic resonance imaging (MRI) equipment, may also affect how a pacemaker works.

Always carry your identification card.

In any kind of accident, your I.D. card will tell people helping you that you have a pacemaker. Your card can be particularly handy if you travel by air. The metal-detection devices in airports may detect the metal in your pacemaker, although they won't damage it. Showing your card may save you some inconvenience.

Your identification card won't last forever. When you need a new one, ask your doctor for one.

Keep all medical appointments.

For your pacemaker to work properly, it should be checked periodically to find out how the leads are working and how the battery is doing.

Today many thousands of people have pacemakers and lead full, productive lives. Pacemakers are usually safe and reliable, but they do need to be checked regularly. The easiest way to check your pacemaker is to take your pulse. Taking medicine as prescribed and seeing your doctor regularly also will be beneficial. Your doctor can explain things you don't understand.