Heart procedure
Defibrillator Implant
An ICD is an implanted device that continuously monitors the heart and delivers a shock or pacing to correct dangerous fast rhythms.
Quick answer
Defibrillator Implant: what it is, why it's done and what happens
An implantable cardioverter defibrillator (ICD) is similar to a pacemaker but can also detect life-threatening fast heart rhythms and deliver pacing or an electric shock to restore a normal rhythm.
- Why it is done: It is used for people at risk of dangerous fast rhythms (ventricular arrhythmias) — for example after a cardiac arrest, with certain inherited conditions, or with a weakened heart muscle — to prevent sudden death.
- What happens: Usually under local anaesthetic with sedation, the device is placed under the skin near the collarbone with leads guided into the heart via a vein under X-ray guidance, taking around 1–2 hours.
What it is
An implantable cardioverter defibrillator (ICD) is similar to a pacemaker but can also detect life-threatening fast heart rhythms and deliver pacing or an electric shock to restore a normal rhythm.
Why it is done
It is used for people at risk of dangerous fast rhythms (ventricular arrhythmias) — for example after a cardiac arrest, with certain inherited conditions, or with a weakened heart muscle — to prevent sudden death.
What happens
Usually under local anaesthetic with sedation, the device is placed under the skin near the collarbone with leads guided into the heart via a vein under X-ray guidance, taking around 1–2 hours.
Recovery
Recovery is similar to a pacemaker, with heavy arm use avoided for a few weeks. The device is checked regularly, and driving may be restricted for a period, which your team will explain.
Good to know
Risks and things to consider
Risks include bleeding, infection, lead problems and occasional inappropriate shocks. Receiving a shock can be distressing, and support and clear advice on what to do are provided.
Education and reference only. This explains the procedure in general terms and is not medical advice. Your own care, risks and recovery will be explained by the team looking after you.
Answers
Defibrillator Implant: frequently asked questions
What does it feel like if the ICD fires?
A shock is often described as a sudden, strong thump in the chest. It can be startling, but it is delivering life-saving treatment. Your team will explain what to do and when to seek help after a shock.
How is an ICD different from a pacemaker?
A pacemaker mainly treats slow rhythms, while an ICD also detects and stops dangerous fast rhythms with pacing or a shock. Some devices combine both functions.
Related
Other heart procedure
Sources
Where this is drawn from
- NHS — Tests and treatments
- NICE — procedure and treatment guidance
- British Cardiovascular Society / relevant professional body
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