A pacemaker is a small device that's placed under the skin in your chest to help control your heartbeat. It's used to help your heart beat more regularly if you have an irregular heartbeat (arrhythmia), particularly a slow one. Implanting a pacemaker in your chest requires a surgical procedure.
Types of pacemakers
Depending on your condition, you might have one of the following types of pacemakers.
- Single chamber pacemaker. This type usually carries electrical impulses to the right ventricle of your heart.
- Dual chamber pacemaker. This type carries electrical impulses to the right ventricle and the right atrium of your heart to help control the timing of contractions between the two chambers.
- Biventricular pacemaker. Biventricular pacing, also called cardiac resynchronization therapy, is for people with heart failure with abnormal electrical systems. This type of pacemaker stimulates the lower chambers of the heart (the right and left ventricles) to make the heart beat more efficiently.
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Why it's done
Chambers and valves of the heart
A normal heart has two upper (receiving) and two lower (pumping) chambers. The upper chambers, the right and left atria, receive incoming blood. The lower chambers, the more muscular right and left ventricles, pump blood out of your heart. The heart valves, which keep blood flowing in the correct direction, are gates at the chamber openings (for the tricuspid and mitral valves) and exits (for the pulmonary and aortic valves).
The conduction system
Your heart's natural pacemaker — the sinus node — produces electrical impulses that prompt your heart to beat.
Your heart's natural pacemaker — the sinus node — produces electrical impulses to stimulate your heart to beat. If these impulses are disrupted, you may need an artificial pacemaker. Depending on your condition, you may have a pacemaker with one to three flexible, insulated wires (leads) placed in a chamber, or chambers, of your heart. These wires deliver the electrical pulses to adjust your heart rate.
Pacemakers are implanted to help control your heartbeat. They can be implanted temporarily to treat a slow heartbeat after a heart attack, surgery or medication overdose. Or they can be implanted permanently to correct a slow or irregular heartbeat or, in some people, to help treat heart failure.
How your heart beats
The heart is a muscular, fist-sized pump with four chambers, two on the left side and two on the right. The upper chambers (right and left atria) and the lower chambers (right and left ventricles) work with your heart's electrical system to keep your heart beating at an appropriate rate — usually 60 to 100 beats a minute for adults at rest.
Your heart's electrical system controls your heartbeat, beginning in a group of cells at the top of the heart (sinus node) and spreading to the bottom, causing it to contract and pump blood. Aging, heart muscle damage from a heart attack, some medications and certain genetic defects can cause an abnormal heart rhythm.
What a pacemaker does
An implanted electronic pacemaker mimics the action of your natural electrical system. A pacemaker comprises two parts:
- Pulse generator. This small metal container houses a battery and the electrical circuitry that regulates the rate of electrical pulses sent to your heart.
- Leads (electrodes). One to three flexible, insulated wires are each placed in a chamber, or chambers, of your heart and deliver the electrical pulses to adjust your heart rate.
Pacemakers work only when needed. If your heartbeat is too slow (bradycardia), the pacemaker sends electrical signals to your heart to correct the beat.
Also, newer pacemakers have sensors that detect body motion or breathing rate, which signal the pacemakers to increase heart rate during exercise, as needed.
Two smaller, leadless pacemakers, which can be implanted directly into the heart, have been approved for use in the United States. Because a lead isn't required, this device can minimize certain risks and speed recovery. Although this type of pacemaker appears to work well and safely, longer term study is needed.
Complications from surgery to implant your pacemaker are uncommon, but could include:
- Infection where the pacemaker was implanted
- Allergic reaction to the dye or anesthesia used during your procedure
- Swelling, bruising or bleeding at the generator site, especially if you take blood thinners
- Damage to your blood vessels or nerves near the pacemaker
- Collapsed lung
How you prepare
Before your doctor decides if you need a pacemaker, you'll have several tests done to find the cause of your irregular heartbeat. These could include:
- Electrocardiogram (ECG). In this noninvasive test, sensor pads with wires attached, called electrodes, are placed on your chest and sometimes your limbs to measure your heart's electrical impulses.
Holter monitoring. This is a portable version of an ECG. It's especially useful in diagnosing rhythm disturbances that occur at unpredictable times. You wear the monitor, and it records information about the electrical activity of your heart as you go about your normal activities for a day or two.
Some personal devices, such as smartwatches, offer electrocardiogram monitoring. Ask your doctor if this is an option for you.
- Echocardiogram. This noninvasive test uses harmless sound waves that allow your doctor to see the action of your heart. A small instrument called a transducer is placed on your chest. It transmits the collected sound waves (echoes) from your heart to a machine that uses the sound wave patterns to compose images of your beating heart on a monitor.
- Stress test. Some heart problems occur only during exercise. For a stress test, an electrocardiogram is taken before and immediately after walking on a treadmill or riding a stationary bike. In some cases, an echocardiogram or nuclear imaging are done.
What you can expect
Before the procedure
You'll likely be awake during the surgery to implant the pacemaker, which typically takes a few hours. You'll have an intravenous line placed, through which you might receive medication to help you relax.
Most pacemaker implantations are done using local anesthesia to numb the area of incisions. Your chest is cleaned with special soap.
During the procedure
One or more flexible, insulated wires are inserted into a major vein under or near your collarbone and guided to your heart using X-ray images. One end of each wire is secured to the appropriate position in your heart, while the other end is attached to the pulse generator, which is usually implanted under the skin beneath your collarbone.
After the procedure
You'll likely stay in the hospital for a day after having a pacemaker implanted. Your pacemaker will be programmed to fit your pacing needs. Arrange to have someone drive you home when you're discharged.
Most pacemakers can be checked remotely. Your pacemaker transmits to and receives information from your doctor's office, including your heart rate and rhythm, how your pacemaker is functioning, and its remaining battery life.
Your doctor might recommend that you avoid vigorous exercise or heavy lifting for about a month. Avoid putting pressure on the area where the pacemaker was implanted. If you have pain in that area, ask your doctor about taking over-the-counter medicines, such as acetaminophen (Tylenol, others) or ibuprofen (Advil, Motrin IB, others).
It's unlikely that your pacemaker would stop working properly because of electrical interference. Still, you'll need to take a few precautions:
- Cellphones. It's safe to talk on a cellphone, but keep your cellphone at least 6 inches (15 centimeters) away from your pacemaker. Don't keep your phone in a shirt pocket. When talking on your phone, hold it to the ear opposite the side where your pacemaker was implanted.
Security systems. Passing through an airport metal detector won't interfere with your pacemaker, although the metal in it could sound the alarm. But avoid lingering near or leaning against a metal-detection system.
To avoid potential problems, carry an ID card stating that you have a pacemaker.
- Medical equipment. Make sure all your doctors and dentists know you have a pacemaker. Certain medical procedures, such as magnetic resonance imaging, CT scans, cancer radiation treatment, electrocautery to control bleeding during surgery, and shock wave lithotripsy to break up large kidney stones or gallstones could interfere with your pacemaker.
- Power-generating equipment. Stand at least 2 feet (61 centimeters) from welding equipment, high-voltage transformers or motor-generator systems. If you work around such equipment, ask your doctor about arranging a test in your workplace to determine whether the equipment affects your pacemaker.
Devices that are unlikely to interfere with your pacemaker include microwave ovens, televisions and remote controls, radios, toasters, electric blankets, electric shavers, and electric drills.
Having a pacemaker should improve symptoms caused by slow heartbeat, such as fatigue, lightheadedness and fainting.
Your doctor should check your pacemaker every three to six months. Tell your doctor if you gain weight, if your legs or ankles get puffy, or if you faint or get dizzy.
Your pacemaker's battery should last five to 15 years. When the battery wears out, you'll need surgery to replace it. The procedure to change your pacemaker's battery is often quicker and requires less recovery time than the procedure to implant your pacemaker.
Because most of today's pacemakers automatically adjust your heart rate to match your level of physical activity, they can allow you to resume a more active lifestyle.
Pacemakers and end-of-life issues
If you have a pacemaker and become terminally ill with a condition unrelated to your heart, such as cancer, it's possible that your pacemaker could prolong your life. Doctors and researchers vary in their opinions about turning off a pacemaker in end-of-life situations.
Talk to your doctor if you have a pacemaker and are concerned about turning it off. You may also want to talk to family members or another person designated to make medical decisions for you about what you'd like to do in end-of-life care situations.
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