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Cardioversion

Electrical cardioversion is used to regulate your heart rhythm. If you have an abnormal heart rhythm condition, known as atrial fibrillation (AF), then an electrical cardioversion can be used to restore a normal heart rhythm.

Your doctor has recommended you undergo a procedure called a cardioversion, or often called an electrical cardioversion.

You might not have heard this medical term before now and may be feeling unsure about the nature of the procedure.

This information sheet will outline what the procedure involves and what risks are involved.

After you read this information sheet, you might still have questions. If you do, please contact the team at Heart HQ. We’re here to help.

What’s a cardioversion?

Electrical cardioversion is used to regulate your heart rhythm. If you have an abnormal heart rhythm condition, known as atrial fibrillation (AF), then an electrical cardioversion is a procedure that can be used to restore a normal heart rhythm.

The procedure is basically an electrical shock to your chest. The shock stops the abnormal hearth rhythm for a brief moment and allows a normal heart rhythm to take over.

As a precaution, most people will be prescribed a blood thinner such as Warfarin, Apixaban, Rivaroxaban or Dabigatran for at least four weeks prior to the electrical cardioversion. This reduces the risk of a stroke occurring during or shortly after cardioversion. You will continue to take the blood thinner for another four to six weeks after a successful procedure.

How does it work?

An intravenous line (IV) will be placed into a vein in your arm. This is for the medical team to administer medication throughout your procedure. You will be given a general anaesthetic to make you sleep for a short time.

While you are asleep, the doctor will use a machine called a defibrillator to deliver the ‘shock’ to your chest. The defibrillator will deliver a specific dose of energy to your heart muscle through patches that will be placed on your chest. This will usually restore your normal heart rhythm. Several attempts may be needed, but the procedure will only take a few minutes.

Electrical cardioversion is more effective than a medication-only approach for stopping AF and restoring a normal heart rhythm. Most patients who undergo successful cardioversion are placed on oral medications to prevent recurrences of AF.

Anaesthetic

This procedure requires you to have general anaesthetic as the ‘shock’ may be uncomfortable. The anaesthetic will be given to you through your IV line.

Most people wake up quite quickly after the procedure without any recollection of the ‘shock’.

Please arrange to have a support person (a relative or friend) collect you from hospital. You’ll also need someone to stay with you that night. You should not drive or make any important decisions in the 24 hours following general anaesthetic.

If you have any concerns about your anaesthetic, please discuss them with your doctor as soon as you can.

What kind of risks are associated with this procedure?

Any kind of procedure carries some element of risk, often very small and rare.

Your doctor has balanced the benefits and risks of carrying out the test against the benefits and risks of not proceeding. If your doctor has recommended this procedure, then your doctor believes there is benefit to you going ahead.

It’s important you understand the risks involved so you can make an informed decision.

Here are the most commonly reported risks and complications associated with a cardioversion.

Common risks and complications (more than 5% of cases)

  • Skin irritation/redness from adhesive pads
  • Recurrence of atrial fibrillation (AF) within 12–24 months
  • The procedure may not be successful—abnormal heart rhythm may persist

Rare risks and complications (less than 1% of cases)

  • You may require a pacemaker—this is usually due to an underlying heart condition
  • Blood clot in the lung
  • Heart attack
  • A stroke—this can cause long-term disability
  • Death as a result of this procedure is rare

Cardioversion info sheet