Electrical cardioversion is a procedure in which an
electric current is used to reset the heart's rhythm back to its regular
pattern (normal sinus rhythm). The low-voltage electric current
enters the body through metal paddles or patches applied to the chest wall.
Cardioversion is used:
The heart has four areas, or chambers. During each heartbeat, the two upper chambers (atria) contract, followed by the two lower chambers (ventricles). This is directed by the heart's electrical system.
The electrical impulse begins in an area called the sinus node, located in the right atrium. When the sinus node fires, an impulse of electrical activity spreads through the right and left atria, causing them to contract, forcing blood into the ventricles.
Then the electrical impulses travel in...
You may take
an anticoagulant medicine, such as warfarin, for a few weeks before and a few weeks after cardioversion. How
long you take anticoagulants will depend on how long you had atrial
fibrillation before the cardioversion procedure.
You might not need to take anticoagulants before the procedure if you have a low risk of stroke. For example, if a test,
transesophageal echocardiogram, has ruled out the
presence of blood clots in the upper heart chambers (atria), you will not need
anticoagulants before the procedure. But you will still need to take
anticoagulants for at least a few weeks after cardioversion, even if no clots were
Additional medicines to help prevent the return of heart
rhythm problems (antiarrhythmics) also may be given before and after the
procedure. Your risk of having atrial fibrillation again is greater if
antiarrhythmics are not used after cardioversion.
cardioversion, you will be monitored to ensure that you have a stable heart
Why It Is Done
Cardioversion is used as an
emergency procedure when symptoms of very low blood pressure, chest pain, or
heart failure caused by rapid, irregular atrial fibrillation are
Cardioversion also is used in nonemergency situations to
stop atrial fibrillation and return the heart rhythm to normal.
For help deciding if you should have electrical cardioversion, see:
The success of electrical
cardioversion depends on how long you have had atrial fibrillation and what is
causing it. Cardioversion is less successful if you have had atrial
fibrillation for longer than 1 year.
treatment, about 9 out of 10 people get back a normal heart rhythm right away. But for many people, atrial fibrillation returns. About 3 to 5 out of 10 people still have a normal heart rhythm 1 year after cardioversion.1 Normal rhythm may last less
than a day or for weeks or months. It depends on your other health
Staying in a normal rhythm is more likely when the
cause of your rhythm problem is not heart disease. But for most people, atrial
fibrillation is caused by heart disease and is very
likely to return.
If your atrial fibrillation returns, you may be able to have
cardioversion again. But if the problem comes back quickly (within a week or
so), having the treatment yet again is less likely to help you.
antiarrhythmic medicines too, they can help you stay
in a normal rhythm longer.
Risks of the procedure include the
A blood clot may become dislodged from the
heart and cause a stroke. Your doctor will try to decrease this risk by using
anticoagulants or other measures.
The procedure may not work.
Additional cardioversion or other treatment may be
Antiarrhythmic medicines used before and after
cardioversion or even the cardioversion itself may cause a life-threatening
You can have a reaction to the sedative given before the
procedure. Harmful reactions are rare.
You can get a small area of
burn on your skin where the paddles are placed.
What To Think About
Cardioversion may be less
successful or may not be recommended if you:
Have had atrial fibrillation for more than a
Olgin JE, Zipes DP (2008). Atrial fibrillation section
of Specific arrhythmias: Diagnosis and treatment. In P Libby et al., eds.,
Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 8th ed., pp. 869–873.
Philadelphia: Saunders Elsevier.
Primary Medical Reviewer
E. Gregory Thompson, MD - Internal Medicine
Specialist Medical Reviewer
John M. Miller, MD - Electrophysiology
November 2, 2010
WebMD Medical Reference from Healthwise
November 02, 2010
This information is not intended to replace the advice of a doctor.
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