Chemical Cardioversion

Chemical Cardioversion

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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. Chemical cardioversion uses medicine to change the heart’s rhythm. During the procedure, you’re given medicine through an IV or by mouth.

When chemical cardioversion is used

An arrhythmia can cause problems such as fainting, stroke, heart attack, and even sudden cardiac death. Chemical cardioversion can help treat several kinds of arrhythmias.

It is often used to treat atrial fibrillation (AFib). With AFib, the atria of the heart quiver instead of beating normally. People with AFib may feel out of breath easily, feel tried, and have a very fast heartbeat. They are also at increased risk for stroke. But your health care provider may not want you to have cardioversion if you have minor symptoms. It also may not be advised if you are an elderly adult, if you have had AFib a long time, or if you have other major health problems. Other treatments might be better for you, such as heart rate control with other medicines.

Chemical cardioversion can also help treat other kinds of arrhythmia. These include atrial flutter, which is similar to AFib but not as severe. It can also be used to treat certain kinds of atrial tachycardia (AT) and ventricular tachycardia (VT). All of these arrhythmias can cause heart rates that are too fast. This can prevent the heart from pumping enough blood.

If this treatment does not work, you may have electrical cardioversion. This is a procedure that resets the heart rhythm with a mild electrical shock.

Risks of chemical cardioversion

Every procedure has risks. The risks of chemical cardioversion include:

  • Creating other arrhythmias

  • The original arrhythmia happens more often

  • Dislodged blood clot that can cause stroke, pulmonary embolism, or other problems

  • No success resetting the heart to a normal heart rhythm

  • Return to the original arrhythmia shortly after the procedure

In rare cases, the procedure can cause a more dangerous heart rhythm. If that happens, you will be given other medicine or an electric shock to stop this rhythm.

In some cases, health care providers lower the risk for blood clots by giving medicine (blood thinner) to help prevent clots. You may be given this medicine before and after the procedure.

Your own risks may vary based on your age, the type of arrhythmia you have, and your overall health. Ask your health care provider which risks apply most to you.

The medicines used for chemical cardioversion each have risks and side effects. Ask your health care provider about the risks and side effects of the medicine you will be given.

Getting ready for your procedure

Talk with your health care provider how to get ready for your procedure. Tell him or her about all the medicines you take. This includes over-the-counter medicines such as ibuprofen. It also includes vitamins, herbs, and other supplements.

Follow your health care provider’s instructions about what medicines to take before the procedure. This includes medicines that prevent arrhythmias. Don’t stop taking any medicine unless your health care provider tells you to.

You may need blood tests before the procedure. This is to make sure the procedure is safe for you.

You may 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 health care provider see if you have any blood clots. Your cardioversion will be delayed if a clot is found.

If you’re at a higher risk for blood clots, your health care 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.

  • Not eat or drink after midnight the night before your procedure, unless your health care provider says it’s OK.

  • Follow all other instructions from your health care provider.

You may 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 a doctor’s office. Or it may be done in your home. A health care 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 AFib or atrial flutter)

  • Adenosine or verapamil (for supraventricular tachycardia)

  • Amiodarone (for atrial tachycardia)

After your procedure

If you are in a hospital or doctor’s office, your heart rate and rhythm will be checked. If you are treated at home, you will need careful follow-up with a cardiologist.

Chemical cardioversion may work very quickly. Or it may take hours to work. In rare cases, it may take up to a few days to work. Your health care provider may want to check your heart rhythm for a period of time after you have been given the medicine. You may need an electrical cardioversion if the medicine did not work. Your health care team will create a new care plan for you if this occurs.

Ask your health care provider about medicine side effects to watch for.

Follow-up care

Make sure to keep all of your follow-up appointments.


When to call your health care provider

Call your health care provider right away if you have any of these:

  • Trouble breathing or chest pain (call 911)

  • Dizziness

  • Fainting

  • Severe side effects from the medicine