Heart procedure
Cardioversion
Cardioversion uses a controlled electric shock, or sometimes medicine, to restore a normal heart rhythm in people with certain fast or irregular rhythms.
Quick answer
Cardioversion: what it is, why it's done and what happens
Electrical cardioversion delivers a brief, carefully timed electric shock to the heart through pads on the chest, resetting an abnormal rhythm such as atrial fibrillation back to normal. It can also be done with medicines.
- Why it is done: It is used to restore a normal rhythm in atrial fibrillation, atrial flutter or other fast rhythms, particularly when they cause symptoms or when maintaining a normal rhythm is preferred.
- What happens: For electrical cardioversion, you are given a short general anaesthetic or sedation so you are asleep, and a synchronised shock is delivered through chest pads.
What it is
Electrical cardioversion delivers a brief, carefully timed electric shock to the heart through pads on the chest, resetting an abnormal rhythm such as atrial fibrillation back to normal. It can also be done with medicines.
Why it is done
It is used to restore a normal rhythm in atrial fibrillation, atrial flutter or other fast rhythms, particularly when they cause symptoms or when maintaining a normal rhythm is preferred.
What happens
For electrical cardioversion, you are given a short general anaesthetic or sedation so you are asleep, and a synchronised shock is delivered through chest pads. The procedure itself takes only minutes.
Recovery
You are monitored until the anaesthetic wears off and usually go home the same day. You should not drive for the rest of the day. Blood-thinning medicine is often continued to reduce clot risk.
Good to know
Risks and things to consider
Risks are small and include skin irritation from the pads, temporary rhythm changes and the small risk of a clot causing a stroke, which is why blood thinners are used. The rhythm can return over time.
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
Cardioversion: frequently asked questions
Will I be awake during cardioversion?
For electrical cardioversion you are given a short anaesthetic or sedation so you are asleep and feel nothing during the shock. You wake shortly afterwards.
Can the abnormal rhythm come back after cardioversion?
Yes. Cardioversion restores normal rhythm but does not always keep it that way, so medicines or further procedures such as ablation are sometimes needed to maintain it.
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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