Pacemakers and defibrillators: Frequently asked questions

What information should I know about pacemakers and defibrillators?

It is always good to get as much information as possible about the need for the device because there are risks and benefits for any device. There are specific conditions in which a device needs to be placed. In some cases, a second or third opinion may be necessary.

There are places to get more information. One place is the American Heart Association and the American College of Cardiology guidelines.

There are conditions where most doctors agree that a pacemaker should be placed. These would be called a Class I condition. For a Class I condition, the device is clearly indicated no matter what. These are generally agreed-upon criteria.

There are Class II indications. In this classification some doctors would go ahead and place the device and others would not.

Are there lifestyle limitations when pacemakers and defibrillators are implanted?

Yes, there are limitations, though most people don't find that there are serious limitations with either type of device. There are some limitations in the first couple of weeks or months after the devices are placed until everything is healed.

How magnetic fields affect pacemakers and defibrillators 

At any time, electrical fields or strong magnetic fields can influence the devices. People who work in power plants, or near alternators of cars, can be affected because they are exposed to heavy magnetic fields. People with pacemakers and defibrillators who use arc welding devices and other kinds of heavy energy that involve magnetism or electricity tend to have problems.

Being an athlete with a pacemaker or defibrillator

If you are an athlete, there can be some limitations regarding what you are allowed to do with a device. Implantable defibrillators, in particular, are placed to prevent death from a heart rhythm abnormality. Still, you could have an episode of a serious cardiac arrhythmia. Before the device corrects that episode, you could get dizzy, light headed, or pass out.

People who have serious or recurrent problems with heart rhythm disturbances may have restrictions and may have activities such as driving curtailed. Usually, when a pacemaker is placed and it is working well, the problem has been corrected and driving is allowed. For implantable defibrillators, the issue is not so simple.

Some things are not recommended, like heavy weight lifting, because that could crack or damage a lead (an electrical connection from the device to the heart). Very extreme upper extremity motion over a long period of time could do the same thing. People who do a lot of exercise and have defibrillators could get a shock from their defibrillators when they don't need a shock because their heart is beating too fast, but it is not due to an abnormal or life-threatening problem.

What is the difference between a pacemaker and a defibrillator?

In electrophysiology we treat heart rhythm problems, such as when the heart becomes irregular, when it gets fast or when it gets slow. There are various ways to treat heart rhythm problems. If the heart rhythm gets very slow and it is not treatable with changes in medications then a pacemaker is needed.

What a pacemaker does is keep the heart beating at the proper rate and from beating too slow. It also will only activate if it is needed, it is not shocking people all the time.

An implanted defibrillator is a bigger device. It is there to prevent death from a cardiac arrest. The device shocks the heart if it needs to be shocked, because of a life-threatening rhythm disturbance from the lower chambers of the heart. It can correct this rhythm. Because it has a pacemaker built into it, a defibrillator also has the capability of stimulating the heart like a pacemaker, to help stop fast rhythms, at times, and to prevent the heart from getting too slow.

How reliable are pacemakers and defibrillators?

These devices are highly reliable. The device often has to be programmed to the patient's needs, the medical condition and the situation.

Are pacemakers and defibrillators covered by insurance?

Cost is an issue. Some people must have a device implanted at any cost, as they most certainly would not survive without that device. In those cases, devices are placed without question. There are other situations where a device implantation may not be completely clear, necessary, or allowed by the present billing structure.

What powers pacemakers and defibrillators?

Currently a high quality of battery – a lithium battery – that wears out slowly is used. There is a point before the battery fails when we have several months to decide what to do. The battery's energy supply does wear out, and it can vary depending on the kind of device--some devices will last maybe five years, maybe ten years, and some people get more life out of it and some get less, depending on the situation and how much they use it.

What we do when the battery reaches its end of life is we open up the pocket where the device is located, which is under the skin, and we unscrew the leads. Then we plug in a new device and close up the skin. We put in a brand new device, often a higher quality, more technologically advanced device.

Are you under sedation during the implant procedure?

It depends on the patient's condition and type of device.

Pacemaker implantation

A pacemaker implant can be done under local anesthesia, but most patients prefer to have sedation, so we use conscious sedation, where the patient can respond to us. We do not generally place a tube down the throat for most people unless we use general anesthesia.

Defibrillator implantation

For defibrillator implants we have to use larger amounts of conscious sedation because we need to test the device. We put the patient into a cardiac arrest and use the defibrillator to shock the patient to normal rhythm. That may sound scary, but in fact that is a very safe procedure. We are prepared for all consequences, and it is something necessary. It requires a deeper sedation during the time of the testing of the device.

For biventricular devices, in which we place leads into the left side of the heart through a vein, the devices and the leads are more complicated to put in. The implants are more challenging and they take longer.

Will a patient ever outgrow the need for a pacemaker or defibrillator?

For most people, the device will be needed for the rest of their life. There are specific individuals who may get a device for prophylactic purposes, or for some reason the condition resolves. That does not happen very often. If it can be determined for a fact that the problem has resolved, then occasionally we remove devices.

Do pacemakers and defibrillators replace heart medications?

We often use devices in conjunction with medications. We do not look at devices in general as a substitute for medication. On the other hand, no medication can substitute completely for an implanted defibrillator. What some people are hoping for is when they get a device put in they can come off all of their medications--this is not the case. In fact, devices usually work with medications much better than they work by themselves. For some people we try to treat life-threatening rhythm disturbances with medication first before we place a defibrillator in.

As time has gone by, we have learned more and more about the safety and effectiveness of implanted defibrillators. We have moved toward using devices more than anti-arrhythmic drugs, specifically, to try to lower the risk of an arrhythmia and its consequences. This is because many of the anti-arrhythmic drugs have side effects and some toxicity. But that does not mean that we stop the other drugs used--such as drugs used to lower cholesterol, or drugs to help the heart condition.

For pacemakers, occasionally we do use medication to keep the heart going faster, but that generally is not the best approach. There are some cases when we use medications to prevent fast rhythms in conjunction with a pacemaker or a defibrillator. For biventricular pacemakers, if the heart function improves enough, we can stop some of the medications that appeared to be necessary before.

For each person there often is some judgment as to what the right thing is to do. Based on those guidelines then there is no way you can tell everyone what the right thing is, it requires some judgment. If there is any concern, consider getting another opinion.

How do I know my doctor is qualified for pacemaker or defibrillator surgery?

There are various types of doctors who put in different devices, and there are different kinds of devices requiring different kinds of expertise.

Cardiac electrophysiologists who are board certified through the American Board of Internal Medicine would be considered in most cases qualified to implant most heart rhythm devices. There are other doctors who are not board certified cardiac electrophysiologists but are cardiologists who have a wide range of experience with device implants. Some of them have more experience with one type than another.

Most cardiologists do not have much experience with implantable defibrillators or biventricular pacemaker defibrillators. Nevertheless, for a straight-forward pacemaker implant, they might be very good. On the other hand one has to recognize that a doctor who is not attuned to the needs of the patient based on their education might be able to place the device but might not understand which would be the right device for the patient.

Other types of doctors implant cardiac devices including, nephrologists, pulmonologists, and others who may be less well trained in the procedure.

With respect to experience, certainly experience would help the doctor better understand the risks and benefits and help to minimize the risks of implanting a device. For a doctor to implant devices safely and effectively, continuous practice doing so is needed. The person who places more devices generally does a better, safer job than the person who replaces an occasional device. There are limits to what is necessary. In other words, if a doctor were to place 2,000 devices in a year, that doctor would be unlikely to be any better than the doctor who implants perhaps 100 pacemakers in a year. However, if the doctor only implants two pacemakers in a year, chances are that doctor would not have the type of expertise that you would want to be assured that you are getting the best service.

The American Heart Association and the American College of Cardiology have specific recommendations for the number of devices a doctor needs to place to be considered competent. This also goes for specific types of devices. If a doctor is very good at implanting pacemakers and might implant several hundred pacemakers in a year, they might never implant a biventricular pacemaker or a defibrillator, so they should not be considered qualified to implant every single type of device.

What change will I see with a pacemaker or defibrillator?

We had one patient who had no chance otherwise to leave the hospital alive. There was no hope for him. We placed the biventricular device, and now he has been fine for over two years. He travels all over the country with his children and grandchildren with no problem whatsoever. This excellent improvement can and does happen. Generally you do see a marked improvement with the biventricular devices.

Defibrillator implantation

With the implanted defibrillators alone (without the capability of bi-ventricular pacing) we don't normally see a marked improvement in the quality of life because these devices act only as protection. They are not necessarily designed to improve the way the heart works. Some people actually get worse with these devices because they do not like to get a shock. The shock may be painful, and it may limit the patient's amount and type of activity. There are some quality-of-life issues of concern for these patients. It has been my experience that an implanted defibrillator alone has a minor effect on quality of life, but it has general lifesaving benefits.

Pacemaker and defibrillator implantation risk

The risks associated with getting a pacemaker or defibrillator implanted is high because of the importance of the device. The device could fail, it could cause infections, there may be implant complications and the implantation process may even lead to death. After a device has been implanted and overworked, it is even possible that the shocks will no longer be effective. These, however, are side-effects that do not occur often enough to justify not getting a device that could greatly improve quality of life in the patient.

Last reviewed: 
January 2016

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