Electric shock treatment (cardioversion)
BMJ Group Medical Reference
Giving your heart an electric shock can mean it gets its normal rhythm back. There's not been a lot of research on this treatment, but it has been used since the 1960s, so doctors think that it works. You'll need a general anaesthetic so you don't feel the shock, and the treatment sometimes leads to other, more serious, abnormal heart rhythms.
Doctors sometimes recommend electric shock treatment to correct atrial fibrillation that started longer than 48 hours ago.  If your irregular heartbeat started in the last 48 hours, your doctor may suggest either drugs or electric shock treatment.
An electric shock is sometimes used as emergency treatment if you suddenly become very ill with atrial fibrillation. 
You may have a type of medicine called a general anaesthetic when you have surgery. It is given to make you unconscious so you don't feel pain when you have surgery.
For more terms related to Atrial fibrillation
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