Having a defibrillator fitted
In this section
What is a defibrillator?
What happens during the operation?
How can a defibrillator help me?
How often will the defibrillator shock my heart?
What are the risks of having a defibrillator fitted?
What other treatments are there?
What will happen if I don't have a defibrillator fitted?
What can I expect after surgery to fit a defibrillator?
This information tells you about an operation to put a device in your chest that helps your heart beat normally. It explains how the operation is done, how the device can help you, what the risks are and what to expect afterwards.
The benefits and risks described here are based on research studies and may be different in your hospital. You may want to talk about this with the do ctors and nurses treating you.
What is a defibrillator?
An implantable defibrillator is a device that's put in your chest to stop an abnormal heart rhythm, particularly one where the lower part of your heart beats too quickly. You may hear these devices called implantable cardiac defibrillators or implantabl e cardioverter defibrillators. Either way, they're often called ICDs for short.
Your heart usually beats at 60 to 100 beats per minute. An abnormal heart rhythm can mean your heart beats at 120 to 200 beats per minute, or even faster. Your heart muscle may flutter instead of beating strongly. If this happens, your heart can stop pumping blood around your body. If your heart isn't made to beat normally again, you will die.
An electric shock can get your heart beating normally again. You may have seen this in medical dramas on television, with actors using electric paddles to shock someone's heart into beating.
An ICD works in the same way as the paddles. It shocks your heart into beating steadily if your heart suddenly beats too fast. The idea is that a small shock given early will slow your heartbeat and save your life.
An ICD is about the size of a pack of cards. It's put under the skin just below your collarbone on the left side of your chest. The device is powered by a battery and has an electric circuit that checks your heartbeat. A lead connects the device to your heart.
If your heart starts to beat very quickly, the ICD sends an electric signal to shock it back into a normal rhythm.
A fast heartbeat is linked to several heart conditions. The information here is only about people who have a heart condition called heart failure.
Heart failure is when your heart stops pumping properly because it's been damaged. About a third of people with heart failure get a dangerously fast heartbeat.1 A fast heartbeat increases the risk that someone with heart failure will die suddenly.
Is a defibrillator suitable for me?
Not everyone with heart failure will need an ICD. Your doctor may suggest one if he or she thinks you have a high risk of dying from your abnormal heart rhythm.
Guidelines from the National Institute for Health and Clinical Excellence (NICE), the government body that advises doctors about treatments, say that you should be offered an ICD if you have heart failure and:1
Your heart stopped pumping because of a fast rhythm and was restarted
Your heart beats too fast for long periods (more than 30 seconds). You may also have blackouts, but not everyone gets this symptom
Your heart beats fast for long periods and struggles to pump out enough blood each time it beats, but you don't have very severe heart failure.
For people who've already had a heart attack, a doctor may recommend an ICD if:1
A test that monitors the electrical activity in your heart shows you could get a dangerously fast heartbeat
You've inherited a heart condition from your parents that increases your risk of dying because of heart problems.
In future, more people with heart failure could be given an ICD. This is because new research suggests that people live longer with an ICD even if they don't have signs of a fast heartbeat and haven't had a heart attack.2 3
If you have very severe heart failure, your heart will be very weak and unable to pump properly. Doctors don't usually recommend ICDs for people with very bad heart failure.
An ICD is slightly different to a pacemaker. The sort of pacemaker used in heart failure helps people if the right side of their heart doesn't beat in time with the left side.4 5 It gives out a constant, regular electric pulse to keep your heart beating regularly. This helps with symptoms such as shortness of breath and swollen feet and ankles.
Some people have a pacemaker combined with an ICD.
What happens during the operation?
An operation to put an ICD in your chest usually takes between 45 minutes and an hour. You'll need to stay in hospital overnight. Most people are in hospital for two to four days.6
Preparing for the operation
You'll have tests, including a blood test and an electrocardiogram (ECG). An ECG records the electrical activity of your heart as a tracing on a graph. Your ICD is specially programmed to spot your abnormal heart rhythm. Your doctor uses your test results to do this.
If you're a man, you may have to cut or shave your chest hair.
If you take a drug called warfarin, you may need to stop taking it a few days before the operation. That's because warfarin increases your risk of bleeding during surgery. Check this with your doctor.
You'll probably only need a local anaesthetic. This will numb your chest. You'll also be given a drug called a sedative through a vein in the back of your hand to make you calm and sleepy. You won't see anything or feel any pain during surgery, but you might be aware of what's going on around you. Operating theatres can be noisy, and you may hear the sound of monitors checking your heart rate and blood pressure. A nurse or the anaesthetist will talk to you to make sure you're OK.
The operation
Here's what happens during the operation.
Your doctor will make a cut across your chest just below your collarbone. The cut will be about 8 centimetres (3 inches) long.
The ICD lead is threaded down through a vein into the lower right chamber of your heart. Some ICDs have two or more leads. These go into other parts of your heart.
The doctor takes X-rays of your chest to make sure the leads go in the right place.
Your doctor then makes a small pocket in the fat underneath the skin of your chest. The ICD is placed in this pocket.
Next, your doctor will connect the leads to the ICD and test it to make sure it works. The ICD will gently shock your heart, but it shouldn't hurt.
The cut on your skin is usually sewn up with one long stitch that dissolves later. You may have a dressing over the wound.
Will it be painful?
You shouldn't feel any pain during the operation. Your cut may feel sore afterwards, but you'll be given painkillers to help. If your painkillers don't work, you should tell the nurse or doctor, who'll be able to give you a higher dose or a different type of painkiller.
How can a defibrillator help me?
An ICD can help you live longer if you have heart failure and an abnormal heart rhythm where the lower part of your heart beats too fast or irregularly.7 8
In studies, an ICD reduced people's chances of dying within two years by between a quarter and a third.7 8 The people in these studies had an abnormal heart rhythm and some had already had a heart attack.
For example, in one big study, 14 in 100 people died within two years of having an ICD. This compared with 20 in 100 people who had drugs instead of an ICD.9
Some research suggests that an ICD may help people with heart failure live longer even if they don't have signs of an abnormal heart rhythm and haven't had a heart attack.2 And people who have an ICD combined with a pacemaker live longer than people who only have a pacemaker.3
How often will the defibrillator shock my heart?
An ICD will only shock your heart if your heartbeat gets dangerously fast.
About 4 in 10 people get a shock from their ICD during the first year. About 7 in 10 people have a shock within two years.10 The shock makes their heart start pumping normally again.
A shock can be very painful. It feels like a big thump in your chest, and you might stumble. If anyone is touching you when the shock happens, it won't harm them but they may feel a tingle.
You may feel afraid and upset after a shock. Some people say they feel relieved that the ICD saved their life. You need to go to hospital to have your ICD checked and reset after each shock.
The battery in your ICD lasts for up to seven years.6 11 After this, you'll need a small operation to replace the battery.
What are the risks of having a defibrillator fitted?
All operations have risks, and your doctor should talk to you about the risks of surgery to put in an ICD.
Anaesthetics can have side effects. These are more likely with a general anaesthetic. You may have an allergic reaction to the anaesthetic or get breathing or heart problems. These problems are serious but rare. If you have any allergies, you must tell your doctor.
About 1 in 15 people have problems during or after their operation.2 12 The statistics we give below are from research studies. You can use these statistics as a guide, but it's important to discuss with your doctor how often problems happen in your hospital.
Problems from the operation
You may get bleeding under the cut in your skin after the operation. If the blood builds up and clots, you will get a big bruise called a haematoma. The area will be swollen and feel tender. If this happens, you may need surgery to remove the blood clot or stop any bleeding. Between 1 in 100 and 6 in 100 people get severe bleeding.7
An infection can make your wound hurt, and the surrounding skin may be hot and red. Between 1 in 100 and 12 in 100 people get infections from having an ICD put in.7 You may need to take antibiotics. Some people need to have their ICD removed. If this happens, you can have another ICD fitted when the infection clears up.
Your lung can be punctured during the operation. If this happens, air can leak out of your lungs and get trapped inside your chest. You may feel breathless and have a sharp pain when you breathe in. This happens to less than 1 in 100 people.7 You may need a tube in your chest to drain the air.
Your chest might be bruised after the operation. About 3 in 100 people have severe bruising.9
Your doctor may accidentally tear a small hole in the vein used to pass the leads into your heart. This tear may need to be repaired.
It's possible, but very unlikely, that you will die from this operation. Less than 1 in 1,000 people die because of surgery to put in an ICD.9 12 13
Problems with the ICD
The leads can break or slip out of place. About 7 in 100 people have problems with the leads.12 Problems are most likely to happen in the first six weeks. You may need a small operation to move or replace the leads. Occasionally, the ICD can slip out of place.
Your ICD may not work properly. This happens to between 1 in 100 and 14 in 100 people.7 The most common problem is for something to go wrong with the battery.14 Your doctor will regularly check your ICD once it's fitted. We do know that ICDs are getting more reliable all the time.14 There aren't as many problems with them breaking down as there were 20 years ago.
Your ICD may shock your heart when it's not beating dangerously. This can happen because the ICD mistakes harmless rhythms for dangerous ones. Or it could be that the ICD is faulty or set off accidentally by electrical equipment. In some studies this happened to about 20 percent to 25 percent of people.10 15 16 It happens less often with newer ICDs. New ICDs can also be programmed to sense a quick beat and then re-check it. This means they don't give you a shock if your heart briefly beats too fast and then goes back to normal.
Very occasionally, ICDs cause other heart problems, such as an irregular heart beat (called atrial fibrillation). However, not all studies agree that ICDs cause this problem.17 18 Your doctor should be able to reprogram your ICD to stop this happening.
Security systems that use a magnetic force can interfere with or even damage your ICD. And you may set the alarm off at airports and in shops.
What other treatments are there?
Most people who have heart failure take medicines called diuretics, beta-blockers and ACE inh ibitors. These help your heart to pump properly and help with symptoms such as breathlessness and swollen feet and ankles. You will still need to take these drugs if you have an ICD.
A kind of abnormal heartbeat where the lower part of your heart beats too quickly can be treated with a drug called amiodarone (brand name Cordarone). There are other drugs similar to amiodarone, but they don't seem to help people with heart failure. These drugs are called antiarrhythmic drugs.
Amiodarone can slow down your heart. Some studies show that people who take amiodarone live longer than people who don't. But other studies show that it doesn't help.19 20
Research does show that people who have an ICD are less likely to die suddenly than people who take amiodarone.11
If you have an ICD, your doctor may suggest you also take amiodarone. This makes it less likely that the ICD will need to give you a shock.
Amiodarone has side effects. The most common side effect is feeling sick. And because amiodarone makes your heart beat more slowly, you might feel faint. This happens to about 1 in 50 people.20 Amiodarone could also make your skin sensitive to sunlight. And most people who take this drug get small spots in their eyes. If you drive a car, these spots can mean that you're dazzled by headlights at night.
What will happen if I don't have a defibrillator fitted?
Some people choose not to have an ICD. They may not want to have an operation or not want their heart to be shocked.
If you decide against an ICD, it's hard to say how likely it is that your heart will beat dangerously fast. But we know from studies that people with heart failure and a fast heartbeat who have an ICD fitted tend to live longer than people who don't have an ICD.7 8
What can I expect after surgery to fit a defibrillator?
Immediately after your operation
When you leave the operating theatre, you'll go to the recovery area until you're fully awake. The area of your chest where the cut was made will feel numb for several hours. You'll probably feel sleepy at first, but you'll be able to get up and walk around as soon as the sedative has worn off.
Someone will re-check your ICD before you leave hospital. He or she may put a sensor above your chest to see if the ICD responds. This doesn't hurt, but you may feel your heart beat a bit faster.
Going home
You should be able to go home the next day. You're likely to feel more tired than usual for a day or two after surgery.
Your chest may feel sore for a few days and it might look bruised and swollen. Painkillers can help. It's a good idea to wear a loose top that doesn't rub your wound.
Your doctor or nurse will tell you when and how to remove any dressings over your cut. You'll also get advice on when you can go back to work.
It's best to avoid moving your shoulder and arm too much for a few days, and you should avoid lifting anything heavy. You'll probably need a week or two to recover.
You may be able to feel the ICD under your skin. This can feel strange at first, but most people quickly get used to it. It can be harder to get used to the idea that a machine in your body can shock your heart. Some people feel vulnerable and worry that the ICD may not work. But other people feel reassured knowing that the ICD could save their life. Ask your hospital if there's a support group in your area for people with heart failure or ICDs.
Some hospitals give people a card with technical information about their ICD. It is important that you carry this with you when you go out in case you need medical treatment in an emergency.
An ICD can't stop your heart failure getting worse. Some people have their ICD taken out when they become very ill because they don't want it to restart their weak heart.
There are some areas of your life that will be affected by your ICD.
Driving
If you drive, you'll need to tell the Driver and Vehicle Licensing Agency (DVLA) and your insurance company that you have an ICD. If you've had a fast heart beat before, you won't be able to drive for six months after your ICD is fitted. After this, you can only drive if your ICD has not shocked your heart for six months and your doctor regularly checks that your ICD still works.
You must stop driving for a month if your doctor reprograms your ICD. It's important to talk to the DVLA or your doctor about these rules. You can find out more at the DVLA website (http://ww.dvla.co.uk).
Security systems
Security systems such as metal detectors at airports can trigger your ICD. It's safe to go through them, but don't linger. It's best to tell security staff that you have an ICD as the security system will detect it.
Electrical equipment
Electrical equipment with magnets can affect your ICD. Large stereo systems and power generators contain magnets. Talk to your doctor about what to avoid. Household appliances such as televisions, washing machines, microwaves, radios and electric blankets won't interfere with your ICD.
It's safe to use a mobile phone, but it will affect your ICD if you put it too close (under 15 centimetres, or 6 inches). It's best to hold it to the opposite ear from your ICD.
Other treatment
Some medical treatment (such as radiotherapy) can damage your ICD. Whenever you have medical treatment, tell the doctor treating you that you have an ICD. The ICD may need to be turned off during some operations.
You won't be able to have a scan called an MRI. This uses strong magnets that will damage your ICD.
Flying
You can travel by plane if you have an ICD. Check your travel insurance though, as it may not cover your heart failure.
Activities and hobbies
It's safe to do things that increase your heart rate and make you out of breath, but you need to warm up slowly so that your heart rate has time to adjust. Your hospital should advise you about how much you can do.
You may want to avoid activities that could be dangerous if your ICD shocks your heart, such as cliff walking or swimming alone.
You can have sex as soon as you feel able to. But avoid putting pressure on your arm or chest for the first few weeks.
It's important that you know what to expect from your ICD and understand the risks and benefits of having one. If you have any questions, ask your doctor or nurse.
Sources for the information on this page:
National Collaborating Centre for Chronic Conditions. Chronic heart failure: national clinical guideline for diagnosis and management in primary and secondary care. July 2003. NICE clinical guideline 5. Available at http://www.nice.org.uk/cg005 (accessed on 15 September 2006).
Bristow MR, Saxon LA, Boehmer J, et al. Cardiac-resynchronization therapy with or without an implantable defibrillator in advanced chronic heart failure. New England Journal of Medicine. 2004; 350: 2140-2150.
Cleland JG, Ghosh J, Freemantle N, et al. Clinical trials update and cumulative meta-analyses from the American College of Cardiology: WATCH, SCD-HeFT, DINAMIT, CASINO, INSPIRE, STRATUS-US, RIO-Lipids and cardiac resynchronisation therapy in heart failure. European Journal of Heart Failure. 2004; 6: 501-508.
Bradley DJ, Bradley EA, Baughman KL, et al. Cardiac resynchronisation and death from progressive heart failure: a meta-analysis of randomised controlled trials. Journal of the American Medical Association. 2003; 289: 730-740.
Linde C, Braunschweig F, Gadler F, et al. Long-term improvements in quality of life by biventricular pacing in patients with chronic heart failure: results from the Multi-site Stimulation in Cardiomyopathy Study (MUSTIC). American Journal of Cardiology. 2003; 91: 1090-1095.
National Institute for Health and Clinical Excellence. Implantable cardioverter defibrillators for arrhythmias: review of technology appraisal 11. January 2006. NICE technology appraisal 95. Available at http://www.nice.org.uk/page.aspx?o=TA95 (accessed on 24 July 2006).
Ezekowitz JA, Armstrong PW, McAlister FA. Implantable cardioverter defibrillators in primary and secondary prevention: a systematic review of randomised, controlled trials. Annals of Internal Medicine. 2003; 138: 445-452.
Desai AS, Fang JC, Maisel WH, et al. Implantable defibrillators for the prevention of mortality in patients with nonischemic cardiomyopathy: a meta-analysis of randomised controlled trials. Journal of the American Medical Association. 2004; 292: 2874-2879.
Moss AJ, Zareba W, Hall WJ, et al. Prophylactic implantation of a defibrillator in patients with myocardial infarction and reduced ejection fraction. New England Journal of Medicine. 2002; 346: 877-883.
Klein RC, Raitt MH, Wilkoff BL, et al. Analysis of implantable cardioverter defibrillator therapy in the Antiarrhythmics Versus Implantable Defibrillators (AVID) Trial. Journal of Cardiovascular Electrophysiology. 2003; 14: 940-948.
The Antiarrhythmic Versus Implantable Defibrillators (AVID) Investigators. A comparison of antiarrhythmic drug therapy with implantable defibrillators in patients resuscitated from near-fatal ventricular arrhythmias. New England Journal of Medicine. 1997; 337: 1576-1583.
Kron J, Herre J, Renfroe EG, et al. Lead- and device-related complications in the Antiarrhythmics Versus Implantable Defibrillators Trial. American Heart Journal. 2001; 141: 92-98.
Rosenqvist, M, Beyer, T, Block, M, et al. Adverse events with transvenous implantable cardioverter defibrillators: a prospective multicenter study. Circulation. 1998; 98: 663-670.
Maisel WH. Pacemaker and ICD generator reliability: meta-analysis of device registries. Journal of the American Medical Association. 2006; 295: 1929-1934.
Wood MA, Stambler B, Damiano RJ, et al. Lessons learned from data logging in a multicenter clinical trial using a late-generation implantable cardioverter defibrillator. Journal of the American College of Cardiology. 1994; 24: 1692-1699.
Grimm W, Flores BF, Marchlinski FE. Electrocardiographically documented unnecessary spontaneous shocks in 241 patients with implantable cardioverter defibrillator. Pacing and Clinical Electrophysiology. 1992; 15: 1667-1673.
Curtis AB, Bigger JT, DiMarco JP, et al. Epicardial cardioverter defibrillators do not cause postoperative arrhythmias. American Journal of Cardiology. 1998; 82: 1114-1117.
Florin TJ, Weiss DN, Peters RW, et al. Induction of atrial fibrillation with low-energy defibrillator shocks in patients with implantable cardioverter defibrillators. American Journal of Cardiology. 1997; 80: 960-962.
Piepoli M, Villani GQ, Ponikowski P, et al. Overview and meta-analysis of randomised trials of amiodarone in chronic heart failure. International Journal of Cardiology. 1998; 66: 1-10.
Amiodarone Trials Meta-analysis Investigators Effect of prophylactic amiodarone on mortality after acute myocardial infarction and in congestive heart failure: meta-analysis of individual data from 6,500 patients in randomised trials Lancet. 1997;350:1417-1424.
2007-04-05 10:35:59
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answer #8
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answered by jwjkrjstorm 4
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