Living with an Implantable Cardioverter Defibrillator

The ICD is the size of a small, about the size of a match box, containing a small
generator, battery and small computer. There are leads that come out if the ICD
box which attach to your heart. Both the generator and leads are inside your body
so you can’t see them. The ICD checks how your heart is beating and corrects any
abnormal heart rhythms automatically through the thin leads.

Young people who may require an ICD might have different conditions. However,
no matter what the underlying condition is, if your doctor has discussed an ICD it will
mean that due to your condition there is a risk of dangerous arrhythmias developing
that will need immediate treatment.

How your heart works:

The heart is a special kind of muscle which acts as a pump to keep blood moving
around the body. The pumping action of the heart muscle is initiated by an
electrical impulse which passes through the walls of the heart, causing them to
contract. This electrical impulse starts in a specialised area of heart tissue in the right
atrium called the sinoatrial (SA) node. It then passes from the right atrium through to
the ventricles via the atrioventricular (AV) node. As the impulse passes through the
right atrium and left atrium, it makes these chambers contract and pump blood into
the ventricles below. As the impulse passes through the ventricles, it has the same
effect. As the ventricles contract, blood is forced out of the heart. Blood in the right
side of the heart is forced to the lungs to pick up oxygen and blood in the left side of
the heart travels to the body to deliver oxygen and nutrients. The electrical impulse inside the heart is something that happens naturally and it travels through the heart each time it beats.

Depending on your condition, this electrical conduction can become disrupted
causing the heart to beat abnormally.
If you have questions about your condition, you can call and speak to your clinical nurse specialist or speak to them or your doctor in clinic appointments.

Two abnormal heart rhythms that may be discussed with you:
- Ventricular Tachycardia (VT) – this is an abnormal rhythm that can originate in the bottom chambers of the heart instead of the top chambers at the SA node. It can cause the heart to beat extremely fast, meaning it does not have time to fully fill with blood between each beat. This makes it hard for the heart to pump blood to the body, which can cause a drop in blood pressure causing a person to faint, or can lead to a cardiac arrest.
- Ventricular Fibrillation (VF) – this is when all the heart muscles cells are firing at the same time meaning the heart is not able to make a co-ordinated movement to contract and pump blood out of the heart to rest of the body. This is known as a cardiac arrest.
Both of these types of rhythm can be very dangerous and if left untreated can
cause sudden death. Fortunately, there are treatments to help manage these
rhythms including medications and also the implantation of an ICD

The ICD works by continually monitoring the heart’s rhythm. If the ICD detects that there is an abnormal heart rhythm it will charge and quickly deliver a shock. The shock is a small amount of electricity that is sent down the leads and spreads across the heart. This electricity stuns the heart, stopping the arrhythmia, and resetting the heart to its normal rhythm. This is known as a defibrillation.

Another treatment that the ICD can give is pacing. Pacing is not required for everyone who has an ICD, but it is available on some ICD’s, should someone need it. Pacing is when the ICD provides some electrical stimuli to cause the heart muscle to contract to trigger a normal heartbeat. This is very different to the shock. This is needed for some people who have very slow heart rates or those that experience pauses.

In some circumstances, a slightly different form of pacing can be used to help treat arrhythmias. This is called anti-tachy pacing (ATP), you may hear your doctor talk about this. This is a type of pacing where the ICD will start to pace the heart during an arrhythmia, this pacing is faster than the arrhythmia and is used to interrupt and slow down the arrhythmia to bring it under control. This pacing is not always successful and does not work on all of the dangerous heart rhythm such as VF. The ICD will always have a failsafe option to shock if the ATP doesn’t work.
All ICD’s continuously monitor the heart’s rhythm and will record abnormal heart rhythms and treatments. If it detects a short abnormal rhythm, that does not need treatment it can record that episode and send it via your home monitor device (explained later in the leaflet) to the team to review. This can be very useful and reassuring if you have symptoms, as you can send us a ‘download’ (which is another word for how the team reads the ICD) from home and we can see if the symptom you experienced is due to an abnormal rhythm or no

It can vary person to person, but the shock has been described by other young people as a very forceful punch to the chest. Some younger children may not know how to describe the shock, and may talk about a pain in their tummy.

If your heart has developed an arrhythmia, it is likely that you will experience symptoms such as; heart palpitations, dizziness or light-headedness and fainting. In most cases, we would expect you to faint before you receive the ICD shock. This means you may not even feel the shock.

However, some people may not feel symptoms as all, but you device will be able to pick up any irregularity and keep you safe.

If your ICD is pacing, it is very unlikely you would feel this.

It’s important to know, that we do not expect you to have shocks regularly. In fact, you may not ever have a shock from your ICD. The ICD is a way you can be kept safe and to protect you from collapse and sudden death.

If you feel faint or dizzy, find somewhere safe and sit or lie down immediately. This
could be an early sign that your heart rhythm is turning into an abnormal rhythm. The
ICD may be ready to give you a shock, and it is safer that you’re sitting or lying down
when this happens.

If you have a shock we recommend that you attend A andvE to be reviewed, even if you feel well. If you are home and it does not delay attending hospital you can send a download.

If you have more than one shock or still feel unwell afterward the shock, stay where you are and ask someone to ring 999 for an ambulance. It will help if they can tell the operator that you have an ICD. You will need a check-up in hospital to make sure your heart rhythm is back to normal.

Whenever the ICD has given a shock, it is likely we will organise to see you soon after in an appointment just to make sure the ICD setting are working well and medications (if you are taking any) are right for you.

There are three types of ICD’s that your doctor might talk about. Below is some information about each of the types of ICD’s that you may hear about.

Transvenous ICD

This ICD is about the size of a matchbox; it contains a small generator, battery and small computer. This is placed under the skin, below the collarbone, typically on the left side. There are leads which come out from the top of the ICD, these are threaded through the veins that travel towards your heart. The lead is then threaded further down into the bottom the right ventricle. Once the lead is placed they are attached to the ICD box.

The benefits of the transvenous device are it can pace the heart if required. Some people may require pacing more regularly, in these instances a second lead will be added, which is threaded through the vein to the top chamber of the heart, in the right atrium. Not everyone who has a transvenous ICD will need pacing or a second lead.

Subcutaneous ICD

The subcutaneous ICD is slightly bigger than the transvenous device, it is wider, although slightly flatter. It also contains a small generator, battery and small computer. However, the placement of the ICD box and the leads is slightly different.

The subcutaneous ICD box is placed under the skin, on the left side of the chest wall, outside the ribcage, under the left arm. It too has a lead which comes out of the top, however in this case instead of the lead being placed inside the heart, the lead is placed on the front of the chest on top of the breast bone. The subcutaneous device is not suitable for all patients

1. It is unable to provide pacing at the moment therefore not suitable for anyone who may need pacing. (New developments in wireless technology may mean this could change in the future).

2. Because the leads are not directly in the heart, for some people it may not be able to pick up the heart signals accurately.

All patients will need to undergo screening beforehand to assess their suitability for this device. This is to check that the subcutaneous ICD will correctly monitor your rhythm

Subcutaneous ICD screening is a way for the team to understand how the ICD will read your heart signals. It involves having an ECG whilst lying down, standing up and whilst exercising (usually on a treadmill).

Epicardial ICD

The epicardial ICD, is similar in size the transvenous, so about the size of a matchbox. It sits in a pocket made in the abdomen and the leads are placed to sit on the outside of the heart.

This device is more likely to be used in very young patient; babies or infants or those who have had complications from another device or if they are undergoing cardiac surgery.

The incision sites for this ICD are generally larger, patients also may need to have a small drain inserted afterwards and recovery can take a little longer.

The decision as to which ICD you will have will depend on a number of things including; if pacing is required, results of the subcutaneous ICD, age, size, and underlying cardiac condition.

The decision will be discussed with you, your cardiologist and the electrophysiologist (this is the doctor whose job it is to implant and looks after your ICD)

You will have your ICD fitted in an operation while you are under general anaesthetic (medication that makes you sleep). Your doctor will explain all about the operation.

The procedure involves a five to 10cm incision on your chest wall either on the side or under the collarbone or on your abdomen, depending on which ICD you have, to put the ICD in. While you are under anaesthesia the team will use both local anaesthetic and pain medication. So immediately after waking up you we wouldn’t expect you to experience any pain.

Once you wake up, you will have a dressing over the top of the ICD site. After the operation we will continue to give you regular pain medication, so you are comfortable, if you have any discomfort you can tell your nurse who can give you more pain relief medication.

Some patients may feel a little sick after having a general anaesthetic, if you wake feeling sick the nurse can always give you some anti-sickness medication

Once the ICD has been in for some time, the wound where the ICD is fitted will heal and will leave a small scar, about the width of the ICD. It is important to start with, to keep the wound clean and dry.

In time, once the wound has healed and the scab has come away, you may use some creams to help with the appearance of the scar. The clinical nurse specialists will be able to help advice when the right time is for this is.

At discharge we also might recommend using some tape to use over the scar, this can aid the healing and help to improve the appearance of the scar.

More information will be given to you at the time by the nurse specialists.

We recommend that you refrain from exercise and sports for the first six weeks, usually waiting until after your first follow-up appointment. This is important to help the ICD scar heal and for the ICD leads themselves to heal properly in or around your heart.

Whilst ICD’s are extremely beneficial and life saving devices, as with many things there are ‘pros and cons’. Although the ‘cons’ or complications that might arise with ICD’s are rare, it is important that you are aware of them. Some of the risks of ICD’s are discussed below, it is important to remember that we do not expect them to happen and we would not recommend the ICD if we felt the risks of the ICD outweighed the risk of the arrhythmia.

Infection

Infection is caused when bacteria gets into your ICD wound where the ICD sits or onto the leads. There are a number of ways in which this can happen, either through the wound site itself (in the initial recovery period) or through other areas on your body where you might have an infection that could enter the blood stream. For instance, it is important to look after your teeth as your gums have lots of small blood capillaries and an infection in your mouth/ gums could be a way that bacteria can enter the blood stream. Tattoos and piercings are also another way that bacteria can enter the body.

Endocarditis

Endocarditis is a serious infection that affects the inner lining of the heart. It is also caused by bacteria entering the blood stream. Endocarditis can make someone become extremely unwell and left untreated can be dangerous. Treatment involves a course of IV antibiotics, via a cannula, over a number of weeks in hospital and replacement of the ICD.

How to reduce the risk of infection:

- It is extremely important that the skin is cleaned well the night and the morning of the procedure to reduce the risk of infection with soap and water!

- Skin wipes will be offered

- Antibiotics are given when you come in for you procedure

- Monitoring of the wound after your ICD implant – the nurse practitioner will discuss this with you in more detail when you come for your ICD

- Reduce the risk of infection by having good oral hygiene and regular teeth brushing

- Avoid piercings or tattoos

Inappropriate shocks are when the ICD delivers treatment ‘or a shock’, when it wasn’t supposed to. Again this is a rare complication, but occurs when the ICD misreads your underlying normal rhythm, and thinks it is abnormal/ dangerous so therefore treats it with a shock. This can also occur if there is a fault with the device or lead.

The only way to know for sure if a shock is appropriate or inappropriate is for the ICD to be ‘interrogated’ (downloaded). Again, inappropriate shocks is not something we expect to happen. If however, you think you have had an inappropriate shock it is important to let us know.

Call the clinical team and let them know and they will advise you what to do. If you have had a shock we recommend you attend A&E for review, even if you feel fine.

If you have had a shock and feel unwell you should call an ambulance.

Inform the paramedics that you have an ICD inserted. They will be able to assess your rhythm and manage the ICD if needed.

In the first 24 hours after having the ICD inserted, there is a small risk that the ICD lead may move. We will perform X-Rays when you return to the ward and the following morning to check the ICD lead.

If there is movement of the lead it will involve a repeat procedure to re- attach the lead before you go home.

Once the initial six week recovery period has passed it is extremely rare for the lead to move, however if there is a concern that the lead has moved when you are at home, we will bring you into hospital to check. If this is the case, we may have to admit you to reposition the lead.

Lead fractures and complications

Lead fractures and complications with leads are also rare. They can occur due to wear and tear. The ICD is able to detect problems with leads and send information to the team via the home monitoring device. There is a particular issue relating to leads as they cross from the outside of the chest under the collarbone. It is important to be aware that arm/shoulder movement have been raised as contributing to this. However we encourage our young patients to have a healthy lifestyle (within the constraints of their condition) and we do not discourage patients to take part in hobbies and activities they enjoy on account of the ICD. However we encourage our patients to speak to their cardiology team about exercise and activity limitations and guidance.

When you go home, we will give you a home monitor. This is a little computer monitoring box that plugs into your bedroom. This monitor is designed to keep an eye on the health of your ICD (including the leads) if there is any problems it will alert the team here at GOSH via the device manufacturer, so we can contact you if any intervention is needed.

You will also be given an ID card once the ICD has been inserted. This has information about your ICD and programming. You should keep this card on you at all times, it contains information about you that may be needed my medical professionals and can also be useful in places like airports

The battery of the ICD will last roughly eight to 10 years. It is dependent on how
much it used, shocks and pacing will deplete the battery. We check the battery every time the ICD is downloaded.

When the battery has less than one year left, we will start planning to bring you in for an ICD box change. This involves removing the ICD box and replacing with a new one. This is usually not so painful and the recovery is quicker as the pocket in which the ICD sits has been well established. We use the same scar as the first time so you shouldn’t have additional scars.

The leads of the ICD can last and toward 15 to 20 years. These may need to be changed in the future, but this will likely be when you are an adult and seen in the adult hospital

Exercise and sport

It is important to refrain from sport and PE for the first six weeks to allow your body to heal following the ICD insertion.

Once you have had your first follow-up you should be able to go back to the activities you did prior to your ICD insertion, unless your doctor has told you otherwise. For some patients, the team may want you to undergo an exercise test before resuming normal activities.

There are some cardiac conditions were it is important not to push yourself too hard in sports or competitive activities, please follow the advice from your cardiologist. We do advise against contact sports such as rugby, martial arts or boxing for those with ICD’s, this is to avoid damage to the device and any pain to yourself. We can review this on a case by case basis with your consultant and the electrophysiologist. There are some companies that design clothing with additional padding that can protect your device. Please ask your clinical nurse specialist or team for more information.

School and College

Once the ICD has been inserted and you have recovered you may return back to school. Most patients usually require a week to recover following surgery before re- starting back at school. This is something you can discuss with your clinical nurse specialist. Your clinical team should be able to provide you with a letter for school detailing more information about your condition and the ICD

An AED is an emergency life-saving device that can be used by anyone to help restart the heart in the event of a cardiac arrest. As a service we recommend there use in any area used by the general public, including schools and colleges.

As you would have an ICD implanted, the likelihood of an AED being required is extremely unlikely, as the ICD will have likely treated the arrhythmia by the time AED is attached. However, if you were to collapse and were unconscious by the time an AED is on the scene, it should still be used. It will only shock if required.

Any shock given by the AED will not damage the ICD, as these are built to withstand external shocks

If you are a driver, or want to learn to drive in the future, you must tell the Driving Vehicle Licensing Agency if you have an ICD and your cardiac condition if it could affect your driving. Failure to do so could result in a fine.

The DVLA will contact your doctor to advise whether driving is safe based on your cardiac condition. If you have had your ICD implanted due to a cardiac arrest then you will be unable to drive for the first six months, if you have had the ICD implanted as a precaution then you will be unable to drive for the first month.

Find out more on the DVLA website.

Some electronic devices may cause interference with your ICD. That is because they may contain a magnet, use Bluetooth or radiofrequency technology that could interfere with the device, below are some more common examples of devices toy come into contact with. However, if you are ever in doubt we recommend you seek advice from the manufacturer or pacing team.

Mobile phones

We advise you keep all phones at least six inches (15cm) away from your ICD. Some more recent smartphones. i.e. the iPHONE 12 contain magnets which when placed directly on the ICD can cause changes to the function of the ICD. If an ICD does come into contact with any magnetic field, it will alarm and make a ‘beeping’ noise. As soon as the magnet is removed, cardiac device function will resume and work normally.

Wireless headphones and wireless gaming controllers

Keep six inches (15cms) away from the ICD. Avoid draping headphones or wires around neck or near the ICD.

Personal activity trackers

You may use an activity tracker, however we would advise you use this on the opposing arm to your ICD and to keep it six inches (15cms) away from your ICD. We also recommend you remove this when going to sleep, as there is a risk the device could become close to your ICD whilst sleeping.

Electronics around the home

Most electronic house hold devices such as microwaves, should not interfere with your ICD. The exception to this is an induction hob. This type of hob creates an electromagnetic field that can interfere with pacemakers, so may affect some types of ICD’s. We would advise maintaining a distance of 12inches (30cms) from induction hobs if you have one in your home

Going abroad for holiday or work will not affect your ICD, but remember the precautions to take about airport security checks in previous paragraphs. If you have trouble obtaining travel insurance from your usual provider, some cardiac charities, such as the British Heart Foundation have information regarding companies who offer insurance to patients with a range of different heart conditions. Before you go, find out the details of ICD centres near your destination and get in touch with them to warn them. You hopefully won’t need them but carry the information with you all the time, just in case

Security gates and checks

Most shops, libraries and airports have security gates these days. Walking through them at normal speed won’t harm your ICD but move away from them when you have walked through. Security metal detectors, such as those in airports, may detect the ICD, so it is important to carry your identity card with you to show to the security guards.

If you are going to the airport, you should not be searched with a handheld scanner, as it works using strong magnets. Show the security guard your identity card and ask to be hand searched instead

You will need a safety assessment and to let your cardiologist know if you are considering jobs that involve working with strong magnets or generators. (Equipment used for welding and electric drills can increase your risk of inappropriate shocks)

For some careers, such as working in the military or in aviation, an ICD or the underlying heart condition may preclude you from those types of jobs.

It is really important that you attend all follow-up appointments so we can monitor
your heart and the health of the ICD.

We see patients with ICD’s every six months.

Two teams that regularly work with patients with these devices are the Electrophysiology team and the Inherited Cardiovascular Diseases Team.
Electrophysiology Team Arrhythmia

Clinical Nurse Specialist

Telephone: 020 7405 9200 extension 5298 or 0207 813 8568 or the ECG team on extension 1011.

ICD downloads

Email: gosh.pacing@gosh.nhs.uk

Inherited Cardiovascular Diseases Team

Advanced Nurse Practitioner/ ICD nurse:

Telephone: 020 7405 9200 (extension 5108)

Arrhythmia CNS

Telephone: 020 7405 9200 (extension 5139)

Cardiomyopathy CNS

Telephone: 020 7405 9200 (extension 5305)

Team Secretary

Telephone: 020 7405 9200 (extension 8839)

E-mail: icvd@gosh.nhs.uk