What is cardioversion?
There are two ways to
convert your heart to a normal rhythm. They are:
- Electrical cardioversion. An external
defibrillator is used in electrical cardioversion. After you are given a
sedative, a doctor places metal paddles or patches on your chest wall. The
paddles send an electric current to your heart. The electric current resets
your heart rhythm and your heart usually starts in a normal rhythm.
- Chemical cardioversion. Antiarrhythmic medications-such as
flecainide, propafenone, or ibutilide-convert your heart to a normal rhythm by
reducing atrial excitability and stabilizing the heart muscle tissue. Chemical
cardioversion may be used when electrical cardioversion or sedation is
considered unsafe or inappropriate. It is less physically traumatic than
electrical cardioversion, but it is also less effective. Antiarrhythmic
medications also have many potentially serious side effects.
How effective is cardioversion?
cardioversion successfully restores a normal sinus rhythm in about 85% of
people who have recent-onset atrial fibrillation.1
Staying in a normal rhythm is more likely when the underlying cause is not
heart disease. However, in many cases, atrial fibrillation is caused by
underlying heart disease and is highly likely to recur.
you have had atrial fibrillation, the lower your chance is of staying in a
normal rhythm after cardioversion.
What are the risks of cardioversion?
stroke is the most serious risk of cardioversion.
Cardioversion may dislodge a blood clot in your heart, causing a stroke.
However, this risk can be significantly reduced by taking the following
- If your atrial fibrillation has lasted for
more than 48 hours, your doctor will probably prescribe anticoagulants for
several weeks before attempting cardioversion to reduce the risk of
- Your doctor may use a test called
transesophageal echocardiography to assess whether you
have a clot in your heart that could cause a stroke. If the heart is clear of
clots, cardioversion can be attempted.
Anticoagulant medication is taken for 4 weeks after cardioversion.
Other risks of cardioversion include the
- You can get a small area of burn on your skin
where the paddles are placed.
- Antiarrhythmic medications used
before and after cardioversion or even the cardioversion itself may cause a
- You can have a
reaction to the sedative given to you before the procedure. Harmful reactions
- The procedure may not work. Additional cardioversion or
other treatment may be needed.
What are the risks of not having
If you choose not to try cardioversion, you still
will be at risk for problems from atrial fibrillation.
have heart palpitations, chest pain, or shortness of breath, especially during
physical activity or emotional stress. You may also tire easily or have
problems with weakness, confusion, dizziness, or fainting.
are not bothered by symptoms of atrial fibrillation, your doctor may prescribe
medications to slow your heart rate but allow the atrial fibrillation to
You will still probably need to take anticoagulant
medications to decrease your risk of stroke. However, these medications
increase your risk of developing a serious problem with bleeding. You will need
to have your blood tested frequently while you are taking an anticoagulant.
With these blood tests, your doctor can tell whether your anticoagulant
medication is at an effective and safe level.
For more information, see the topic