Introduction
This information will help you understand your choices, whether you share in the decision-making process or rely on your doctor's recommendation.
Key points in making your decision
People who have heart failure sometimes have an abnormal heart rhythm that can cause sudden cardiac arrest and death. This means that their heart stops and they will die unless the abnormal rhythm is fixed right away. An implantable cardioverter-defibrillator (also called an ICD) is a device that gives the heart a shock to stop a deadly rhythm and return the heart to a normal rhythm.
An ICD is often placed in people who have survived an abnormal rhythm that could cause sudden death. This decision aid focuses on whether to get an ICD if you have not had a heart rhythm that could be deadly but are at risk for one.
Consider the following when making your decision:
- Your doctor may suggest an ICD if you are at risk of having an abnormal heart rhythm that could cause sudden death. Tests can show if you are at risk.
- Many medical facts play a role in whether you should get an ICD. For example, the amount of blood your heart pumps (ejection fraction) helps your doctor decide if an ICD is right for you. Your doctor also will consider other health problems you may have.
- The shock from an ICD hurts briefly. It’s been described as feeling like a punch in the chest. But the shock is a sign that the ICD is doing its job to keep your heart beating. The ICD also can use painless electrical pulses to fix a heart rate that is too slow or too fast.
- Your doctor may also recommend that you take medicine to reduce your chance of having a deadly abnormal heart rhythm. Also, some abnormal heart rhythms may be fixed with a procedure called catheter ablation. It destroys some of the heart tissue where the abnormal rhythm starts.
Medical Information
How can heart failure affect heart rhythm?
When you have heart failure, the lower chambers of your heart (the ventricles) aren't able to pump as much oxygen-rich blood as the body needs. Some people who have heart failure also may have abnormal heart rhythms that can cause sudden death.
The heart may beat so fast that the ventricles don't have time to fill with blood. This type of abnormal rhythm is called ventricular tachycardia (say "ven-TRICK-yuh-ler tack-ih-KAR-dee-uh"). Sometimes the heart quivers, or flutters, and stops pumping blood. This is called ventricular fibrillation (say "ven-TRICK-yuh-ler fib-ruh-LAY-shun"). If these abnormal rhythms are not fixed right away, the person may die.
How can an ICD help?
An implantable cardioverter-defibrillator (ICD) is a battery-powered device that can fix an abnormal heart rhythm and prevent sudden death. The ICD is placed inside the chest. It's attached to one or two wires (called leads) that go into the heart through a vein. The ICD is always checking your heartbeat for an abnormal rhythm. If the ICD senses a dangerous rhythm, it gives the heart an electrical shock to return the heart to a normal rhythm.
An ICD also can fix a heart rate that is too slow or too fast without using a shock. It can send out electrical pulses to speed up a heart rate that is too slow. Or it can slow down a fast heart rate by matching the pace and bringing the heart rate back to normal.
Before putting the ICD in your chest, your doctor will program it to send electrical pulses or a shock when needed. Whether you get pulses or a shock depends on the type of problem that you have and how the doctor programs the ICD to respond to it.
In some people who have heart failure, the ventricles don't beat at the same time. If these people also have a risk for abnormal heart rhythms, they may get a device that combines an ICD and a biventricular (say "by-ven-TRICK-yuh-ler") pacemaker. This type of pacemaker uses electrical pulses to make the ventricles pump at the same time. The ICD part of the device can give a shock to fix an abnormal heart rhythm. For more information, see:
How is the ICD placed?
Your doctor will put the ICD in your chest during minor surgery. You will not have open-chest surgery. You probably will have local anesthesia. This means that you will be awake but feel no pain. You also will likely have medicine to make you feel relaxed and sleepy.
Your doctor makes a small cut (incision) in your upper chest. He or she puts one or two leads (wires) in a vein and threads them to the heart. Then your doctor connects the leads to the ICD. Your doctor programs the ICD and then puts it in your chest and closes the incision.
In some cases, the doctor may be able to put the ICD in another place in the chest so that you don't have a scar on your upper chest. This would allow you to wear clothing with a lower neckline and still keep the scar covered.
Most people spend the night in the hospital, just to make sure that the device is working and that there are no problems from the surgery.
You may be able to see a little bump under the skin where the ICD is placed.
How does it feel to get a shock from an ICD?
The shock from an ICD hurts briefly. It’s been described as feeling like a punch in the chest. But the shock is a sign that the ICD is doing its job to keep your heart beating. You won't feel any pain if the ICD uses electrical pulses to fix a heart rate that is too fast or too slow.
There’s no way to know how often a shock might occur. It might never happen.
It's possible that the ICD could shock your heart when it shouldn't. If that were to happen, you would have pain. The shock could make you fall out of bed, and that could injure you. You also might be afraid or worried about when the ICD might shock you again.
In rare cases, the shock could cause ventricular fibrillation. If this happened, the ICD would shock your heart again to stop the abnormal rhythm.
Many people say that they have a good quality of life with an ICD. But shocks—and the fear of shocks—can make some people worry too much. They may be afraid all the time that the ICD might shock them. This worry can reduce a person's quality of life.
Who might want an ICD?
An ICD often is placed in people with heart failure who have survived a dangerous abnormal rhythm. The ICD would protect them if they get another abnormal heart rhythm.
But it also may be offered to people with heart failure who haven't had an abnormal heart rhythm but are at risk for one.
You will have tests to see whether you are at risk for abnormal heart rhythms. These may include an electrocardiogram (EKG), an echocardiogram, or an electrophysiology study.
Your doctor will use these test results and your medical history to figure out whether an ICD could help you. He or she also will rely on guidelines that help doctors find out who might benefit from an ICD.1 These guidelines will likely change often because experts are doing new research and creating new technology. You and your doctor can work together to decide whether you want to get an ICD.
Many medical facts play a role in whether you should get an ICD. Your doctor will look at whether:
- You're taking medicine to treat heart failure and to prevent abnormal heart rhythms.
- You're expected to live more than 1 year.
- Your ejection fraction is lower than normal.
- You have passed out from previous abnormal heart rhythms.
- You have had a heart attack.
- You have class II or III heart failure.
Who might not want an ICD?
Sometimes an ICD is not recommended. You and your doctor may decide against an ICD if any of the following apply to you:
- You're expected to live less than 1 year.
- You have constant abnormal heart rhythms (ventricular tachycardia or ventricular fibrillation) that can't be controlled with medicines. An ICD would shock you repeatedly.
- You have class IV heart failure and heart transplant surgery is not an option. People who have class IV heart failure can't do any physical activity without symptoms. An ICD probably wouldn't help you live longer.
- You have an abnormal heart rhythm that can be fixed with catheter ablation. This is a procedure that destroys some heart tissue where the abnormal rhythm starts.
- You have a mental illness that would be made worse by an ICD or that may keep you from having follow-up checkups.
What are the benefits of an ICD?
An ICD can prevent sudden death from an abnormal heart rhythm. Studies also show that an ICD works better than medicine to help people with an abnormal heart rhythm and heart failure live longer.
- Research has shown that ICDs lower the risk of sudden death in people who have heart failure but don't have heart disease (coronary artery disease). Over a 2-year period, 1 death was prevented for every 25 people who got an ICD.2
- Another study found that ICDs worked even better to lower the risk of sudden death in people who have both heart failure and heart disease. It found that, over a 2-year period, 1 death was prevented for every 18 people who got an ICD.3
- Another study found that medicine (amiodarone) wasn't much better than no treatment in lowering the risk of death from a heart rhythm problem.4
What are the risks of an ICD?
There are several risks to getting an ICD. But the risks are different for each person. The chance of having some problems is very low.
- You could get an infection where the ICD is placed. This happens less than 1 time out of 100 to just over 12 times out of 100. So there is no infection about 88 to 99 times out of 100.5
- The leads that attach to the heart may break or stop working right. This can happen between 2 and 15 times out of 100 after 5 years of having the ICD. So it does not happen about 85 to 98 times out of 100.5, 6 But the risk of a lead breaking or not working right appears to increase over time. One long-term study found that, after 10 years, 20 out of 100 leads had problems. This also means that 80 out of 100 leads didn't have problems.7 If a lead does break or does not work anymore, you would need surgery. The surgery would be more complex than that needed to replace an ICD battery.
- Serious bleeding could occur after placement of the ICD. This happens from 1 to 6 times out of 100. Serious bleeding doesn't happen 94 to 99 times out of 100.5
- A lung could collapse (pneumothorax) from a buildup of air in the space between the lung and the chest wall. This happens less than 1 time in 100. This doesn't happen 99 times out of 100.5
The ICD could shock the heart when it shouldn't. There is no way to know if or when this could happen. It might never happen.
There also is a chance that a manufacturer may recall an ICD for a problem. If this were to happen, you might need surgery to take out the ICD and leads.
What follow-up do you need after getting an ICD?
You will need regular checkups with your doctor to make sure that the ICD is working.
It's important to keep taking your medicines for heart failure. You'll also need to follow a healthy lifestyle to treat heart failure. This may include watching how much fluid you drink, eating healthy foods that are low in salt, and not smoking.
If the ICD gives you a lot of shocks, your doctor may prescribe amiodarone. This medicine helps prevent abnormal heart rhythms and may keep the ICD from sending shocks too often. Your doctor also could suggest catheter ablation to lower the number of times the ICD shocks you. Catheter ablation can lower the chance of some abnormal heart rhythms, such as atrial fibrillation, which could cause the ICD to shock you.
ICDs run on a battery that lasts from 5 to 8 years. To replace the battery, you will need minor surgery.
If you get an ICD, you have to be careful not to get too close to some devices with strong magnetic or electrical fields. These include MRI machines, battery-powered cordless power tools, and CB or ham radios. But most everyday appliances are safe. For more information, see:
If you need more information, see the topic Heart Failure.
Your Information
Your choices are:
- Get an ICD.
- Don't get an ICD.
The decision whether to get an ICD takes into account your personal feelings and the medical facts.
Reasons to get an ICD |
Reasons to not get an ICD |
Are there other reasons you might want to get an ICD? |
Are there other reasons you might not want to get an ICD? |
These personal stories may help you make your decision.
Wise Health Decision
Use this worksheet to help you make your decision. After completing it, you should have a better idea of how you feel about getting an ICD. Discuss the worksheet with your doctor.
Circle the answer that best applies to you.
| I want to do everything I can to prevent sudden death from an abnormal heart rhythm. | Yes | No | Unsure |
| My level of heart failure makes an ICD a good choice for me. | Yes | No | Unsure |
| I am not concerned about an ICD giving me a shock if it could save my life. | Yes | No | Unsure |
| I would be too scared about when the ICD would give me a shock. | Yes | No | Unsure |
| My doctor says I may live 1 year or more. | Yes | No | Unsure |
| I could have catheter ablation instead of an ICD to stop bad heart rhythms. | Yes | No | Unsure |
I would rather try using only medicine to lower my chance of a deadly heart rhythm. |
Yes | No | Unsure |
Use the following space to list any other important concerns you have about this decision.
|
|
What is your overall impression?
Your answers in the above worksheet are meant to give you a general idea of where you stand on this decision. You may have one overriding reason to get or not get an ICD.
Check the box below that represents your overall impression about your decision.
Leaning toward getting an ICD |
Leaning toward NOT getting an ICD |
Return to the topic Heart Failure.
References
Citations
Epstein AE, et al. (2008). ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices): Developed in Collaboration With the American Association for Thoracic Surgery and Society of Thoracic Surgeons. Circulation, 117(21): e350–e408.
Desai AS, et al. (2004). Implantable defibrillators for the prevention of mortality in patients with nonischemic cardiomyopathy: A meta-analysis of randomized controlled trials. JAMA, 292(23): 2874–2879.
Moss AJ, et al. (2002). Prophylactic implantation of a defibrillator in patients with myocardial infarction and a reduced ejection fraction. New England Journal of Medicine, 346: 877–883.
Bardy GH, et al. (2005). Amiodarone or an implantable cardioverter-defibrillator for congestive heart failure. New England Journal of Medicine, 352(3): 225–237.
McKelvie R (2008). Heart failure, search date January 2007. Online version of BMJ Clinical Evidence. Also available online: http://www.clinicalevidence.com.
Eckstein JE, et al. (2008). Necessity for surgical revision of defibrillator leads implanted long-term. Circulation, 117(21): 2727–2733.
Kleemann T, et al. (2007). Annual rate of transvenous defibrillation lead defects in implantable cardioverter-defibrillators over a period of >10 years. Circulation, 115(19): 2474–2480.
Credits
| Author | Marianne Flagg |
| Editor | Katy E. Magee, MA |
| Associate Editor | Michele Cronen |
| Primary Medical Reviewer | E. Gregory Thompson, MD - Internal Medicine |
| Specialist Medical Reviewer | George Philippides, MD - Cardiology |
| Last Updated | August 13, 2008 |
