About us

The Defibrillator support group is a voluntary group set up in association with the Irish Heart Foundation to assist patients with implantable defibrillators (ICD) and their families. Implantable defibrillators are used to treat abnormal heart rhythms which are a leading cause of preventable sudden death.

Coming to terms with a heart condition requiring implantation of a defibrillator involves a period of adjustment for the individual and family. The support group wishes to create more understanding and awareness of the technology in Ireland and also of the growing number of Irish people of all ages who have an implantable defibrillator. 

About 2000 people in Ireland have ICD's. In 2007 the support group held 3 information days for more than 700 people with ICD's and their families. The group publishes a newsletter. All committee members have ICD's and are available to give support directly or via the Irish Heart Foundation.

 ICD Patient Group Newsletter - July 2010

 ICD Patient Group Leaflet

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Implantable Cardioverter Defibrillators (ICDs)

What is an ICD?
An Implantable Cardioverter Defibrillator (ICD) is a small electrical device that monitors the rhythm of your heartbeat. When it detects an abnormal rhythm (arrhythmia) it acts to restore normal rhythm. It may act like a pacemaker when the heart is beating too fast or too slow, delivering a series of electrical impulses, this is known as “pacing”. It may deliver a bigger electrical shock to remedy more serious abnormalities.

Why and when are ICD implanted?
ICDs are generally implanted in people who have had a heart rhythm problem. However sometimes people who have not had a heart problem, but are considered at risk of developing a serious heart arrhythmia may have the device inserted as a precaution.

What does an ICD look like and how is it implanted?
An ICD is a small device with a metal (titanium) cover, about 5 cm x 5m in size and 1 cm thick. An ICD contains a battery-powered electronic circuit that monitors heart function. It is inserted under the skin, near the shoulder. Electrode leads connect the ICD to the inside of the heart. The battery lasts 4-6 years after which a new unit will be inserted.

What causes an abnormal heart rhythm (Arrhythmia)?
The heart is a pump that maintains the circulation of blood through all the organs of the body. The heart muscle contracts and relaxes in a rhythmic fashion, usually at a rate of 60-100 beats per minute. The medical term for an abnormal heart rhythm is Arrhythmia. This means the heart is beating too slow, too fast or irregularly.

There are many different causes of arrhythmias. Arrhythmias can be associated with Cardiomyopathy (heart muscle disorder) or may be experienced by people who have had a heart attack. However people with rhythm disturbances may not have any other signs of heart disease.

Types of Arrhythmia

Ventricular Tachycardia
When the heartbeat is too fast it is called a tachyarrhythmia or tachycardia. This can make you feel dizzy and light-headed. You may have palpitations and may faint. When the heart beats too fast there is not enough time for the chambers of the heart to fill with blood between contractions and thus not enough blood is circulated effectively. As oxygen is carried in the blood, the brain is deprived of sufficient oxygen and this causes feelings of light-headedness. The pacemaker function of your ICD can be programmed to correct this.

Ventricular Fibrillation
When the heartbeat is so fast and chaotic that the heart can’t pump any blood, this is known as ventricular fibrillation. This condition is fatal, but an electric shock from your ICD can correct the heart rhythm.

Ventricular Bradycardia
When the heartbeat is too slow it is called bradyarrhythmia or bradycardia. This can make you feel fatigued or light-headed. Slow heartbeat means that blood is not being pumped quickly enough around the body to supply the organs with sufficient oxygen. The pacemaker function of your ICD can prevent this happening.

What will happen to me when the ICD delivers a shock?
You may experience a number of different sensations. You may feel an abnormal heart rhythm before the ICD treats the rhythm disturbance.

• When the ICD is pacing the heart, treating a fast rhythm, you may experience a painless fluttering feeling.
• If the ICD has to deliver a low-level electric shock it can feel like a thump on the chest and be mildly uncomfortable.
• In the case of more serious rhythm disturbances you may feel dizzy or faint shortly before the shock is delivered and then experience a stronger sensation of being hit really hard on the chest as the rhythm is corrected.

Once the ICD has delivered its treatment and the heart rhythm has been restored you may wish to rest for a short while. You do not need to go to hospital right away. Phone your hospital to tell them you’ve had a shock and they will arrange to check your ICD at your convenience. If you still feel unwell after the ICD has delivered a shock or the ICD gives you a series of shocks, you should contact the emergency services immediately.

Everyone’s experience of ICD treatment will be different. The intensity and frequency of treatment will vary from person to person. Some people experience many shocks in a year while others may never feel the treatment.

Living with an ICD

When can I go back to work?
When you can resume work will depend on the seriousness of your heart problem, your age and if you have any other illnesses. If you have an ICD solely as a precaution, you can probably return to work almost immediately. If you have had serious heart problem, recovery may take at least 6 weeks. If you are a bus or heavy goods vehicle driver, you will need to tell your employers that you have heart problems and have an ICD and you may not be able to presume this type of work. Depending on the seriousness of your heart illness, if your job is very physically demanding or stressful, you may need to change how you work or the type of work you do.

When can I start driving & how will having an ICD affect my car insurance?
Currently there is no Irish legislation regarding driving following the installation of an ICD. Different insurance companies may have different guidelines in relation to covering drivers with medical conditions. Please discuss with your Cardiologist, insurance company and licence issuing authority before driving.

Can I play sports and take part in physical activity?
Walking and other exercise is good for you. In general you should avoid all activities that could damage your ICD or be dangerous should the ICD deliver a shock. Thus contact sports (rugby, boxing etc.) and activities such as climbing ladders should be avoided. Please contact your cardiology clinic to discuss suitable levels of physical activity for your individual situation.

Can I travel by air with an ICD?
Air travel is permitted for people with ICDs, however airport metal detectors can cause some electrical interference. You should inform airport security staff that you have an ICD.

Mobile Phones & Other electrical equipment
There is a small chance of interference from mobile phone signals if the phone is very close to the ICD. For this reason always use the phone on the opposite side from your ICD and don’t keep it in your breast pocket. Security systems in libraries can interfere with ICDs and pacemakers. You should tell staff that you have an ICD and avoid walking through these security systems.

Useful Web Links:

Implantable Defibrillator Support Group
Contact the Irish Heart Foundation 01 6685001 for details.

British Heart Foundation: www.bhf.org.uk 
You can download a very comprehensive book on ICDs from the publications section of British Heart Foundation’s web site.

Irish Cardiomyopathy Support Group: Contact the Irish Heart Foundation 01 6685001 for details.

British Cardiomyopathy Association: www.cardiomyopathy.org  

UK ICD Patient and Family Heart Support Group: www.icdsupport.org.uk 

UK Sudden Adult Death Syndrome Support Group: www.sadsuk.org

Irish Medicines Board Medical Device Leaflets www.imb.ie/EN/Medical-Devices/Information-Leaflets.aspx