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Having Chemical Cardioversion

Cardioversion is a procedure that is done to return your heartbeat to a normal rhythm. It’s done when the heart is beating very fast or irregular. This is called an arrhythmia. The procedure uses medicine to change the heart’s rhythm. The medicine is given through an IV or by mouth. It can be done as a planned procedure or an emergency procedure when you have an unstable irregular heartbeat.

What to tell your healthcare provider

Tell your healthcare provider about all the medicines you take. This includes over-the-counter medicines such as ibuprofen. It also includes vitamins, herbs, and other supplements, and any recreational drug use.

Tests before your procedure

You may need blood tests before the procedure. These make sure the procedure is safe for you. Blood tests can also help find causes for irregular heart rhythms, such as abnormal levels of electrolytes or thyroid hormones. A cardioversion may not work if you have conditions causing abnormal test results that need to be treated, too. 

You may also have a transesophageal echocardiography test before the procedure. This test is a special kind of ultrasound. A thin, flexible tube is put down your throat and into your esophagus. There, the tube is close to your heart. It lets your healthcare provider see if you have any blood clots. Your cardioversion will be delayed if a clot is found.

Getting ready for your procedure

Talk with your healthcare provider about how to get ready for your procedure. Follow his or her instructions about what medicines to take before the procedure. This includes medicines that prevent arrhythmias. Don’t stop taking any medicine unless your healthcare provider tells you to do so.

If you’re at a higher risk for blood clots, your healthcare provider may want you to take blood thinner medicine. You may take this several weeks before and after the procedure.

Make sure to:

  • Ask a family member or friend to take you home from the hospital.

  • Follow any instructions from your healthcare provider about not eating or drinking before your procedure.

  • Follow all other instructions from your healthcare provider.

You will be asked to sign a consent form that gives your permission to do the procedure. Read the form carefully. Ask questions if something is not clear.

On the day of your procedure

The procedure may be done in a hospital or an outpatient facility that has continuous heart rhythm monitoring. A healthcare provider will give you medicine. It may be given through a vein in your arm or hand (IV). Or you may take it by mouth.

The type of medicine is based on your type of arrhythmia and your overall health. Examples of medicines that are used include:

  • Flecainide, dofetilide, propafenone, amiodarone, or ibutilide (for atrial fibrillation or atrial flutter)

  • Adenosine, verapamil, diltiazem, or metroprolol (for supraventricular tachycardia)

  • Amiodarone (for ventricular tachycardia)

After your procedure

Your heart rate and rhythm will be watched for a few hours to see if the conversion worked. 

Chemical cardioversion may work very quickly. Or it may take hours to work. You may need an electrical cardioversion if the medicine did not work. Your healthcare team will make a new care plan for you if this occurs.

Ask your healthcare provider about medicine side effects to watch for.

You may need to take blood thinner medicine, such as warfarin, for several weeks after the procedure. Take this exactly as directed. You may also need to take a medicine to prevent arrhythmias. Take all your medicines exactly as directed.

Follow-up care

Follow up with your healthcare provider, as advised. 

When to call your healthcare provider

Call your healthcare provider right away if you have worsening palpitations. Call 911 or get care right away at the nearest emergency department if any of these occur:

  • Trouble breathing or chest pain

  • Dizziness

  • Fainting

  • Severe side effects from the medicine, such as uncontrolled bleeding if you are on blood thinning medicines

Online Medical Reviewer: Louise Cunningham RN BSN
Online Medical Reviewer: Ronald Karlin MD
Online Medical Reviewer: Steven Kang MD
Date Last Reviewed: 8/1/2020
© 2000-2020 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.