Cardioversion for Atrial Fibrillation
The goal of chemical cardioversion is to make your heart beat regularly (in normal sinus rhythm). It is usually done in a hospital. Some combination of medications (see Treatment/Drug Therapies) are administered intravenously, such as Cardizem, verapamil, ibutilide, or adenosine (a class V antiarrhythmic agent). Doctors monitor you closely for adverse side effects.
Chemical cardioversion is often done in combination with Electrical Cardioversion described below.
Electrical Cardioversion is a medical term for giving your heart a shock with a defibrillator to synchronize it, to make it beat regularly (in normal sinus rhythm). It is often used in combination with Chemical Cardioversion.
During Electrical Cardioversion you are anesthetized and are unconscious when you receive the shock. The shock causes signal producing areas of your heart to discharge all at once. This stops all electrical activity in your heart momentarily, hopefully allowing your normal heart rhythm to take over.
Electrical Cardioversion seems to have the best chance of success in recent onset A-Fib. If your A-Fib just started, it may be a momentary aberration that an Electrical Cardioversion may correct.
Low Risk Treatment
Electrical Cardioversion is considered low risk, but it does have a high risk of forming clots and causing stroke, 2 which is why it is important to be taking anticoagulants like warfarin (Coumadin) both before the treatment and in the three to four weeks following treatment.
What doctors aim for is an INR (International Normalized Ratio) of warfarin in your blood that is between 2.0 and 3.0. (An Electrical cardioversion “stuns” your heart and your Left Arial Appendage where most A-Fib clots occur. Clots may form in the LAA while it is stunned and not beating.) You may have to have your blood tested weekly till your doctor determines you are in this range.
If your A-Fib is so irregular and rapid that it is life threatening, you may be rushed to an Emergency room and be given the anticoagulant Heparin intravenously before your electrical cardioversion.
VIDEO 2: Short animation for patients: covers the electrical function of the normal heart, then the heart in A-Fib, and the risk of clots and stroke; discusses the procedure before, during and after the electrical cardioversion; excellent animations. (:50) By Nucleus Media 3
Electrical Cardioversion + Chemical Cardioversion
Electrical Cardioversion, often combined with Chemical Cardioversion, is considered a standard, routine, low risk treatment option, particularly for recent onset A-Fib patients.
However, sometimes after electrical cardioversion, your A-Fib comes right back. In fact “50 to 75 percent of patients eventually develop Atrial Fibrillation again.” 4 Electrical Cardioversion is a shock to the body and requires general anesthesia. It’s like a mini electrocution. (The Defibrillator paddles, for example, can leave burn marks on the chest.)
Are Repeated Electrical Conversions Dangerous?
People with A-Fib often ask, “How often can I be Electrical Cardioverted? Does it ever become counterproductive or dangerous?” Right now we just don’t know the answer to this question. (Former Senator and NBA basketball player Bill Bradley had three successful Electrical Cardioversions from 1996-1998 without any apparent ill effects. 5 The author has heard of an A-Fib patient who received an Electrical Cardioversion once a month for a year without any apparent problems.)
Don’t Be Frightened
Don’t let this type of video frighten you, or the emergency room scenes in TV shows. It may look and sound traumatic, but Electrical Cardioversion is in fact non-invasive and is one of the easiest and safest short term treatments available for A-Fib.
In a Personal Experiences story, Kris tells of accidentally being awake during an electrical cardioversion (see Personal Experiences story #37). According to Kris, the shock is relatively mild compared to what you often see portrayed in medical dramas on TV.
VIDEO 3: Watch an actual Electrical Cardioversion recorded at the patient’s request: “Me Being Cardioverted” posted by reddy321. 6 But be advised: the patient in this video is partially awake (this is not the norm). This video is a bit unsettling to watch (but not dangerous or painful for the patient).
Last updated: Thursday, October 16, 2014
- VIDEO 1: Short animation explaining electrical cardioversion when in Atrial Fibrillation. YouTube video posted by eMedTV; Last accessed Oct 12, 2014; URL: http://www.youtube.com/watch?v=-jkhQ5Tl2fs↵
- Haines, D. “Atrial Fibrillation: New Approaches in Management.” Un. of Virginia multi-media presentation, 1999, p.2. http://www.a-fib.com/HainesUnOfVirginiaAtrialFibrillation.htm↵
- VIDEO 2: YouTube video posted by Nucleus Media; Last accessed Oct 12, 2014; URL: http://www.youtube.com/watch?v=dC_i8zuclmQ↵
- Heeringa, Jan, et al. Cigarette Smoking and Risk of Atrial Fibrillation: The Rotterdam Study 01/20/2009; American Heart Journal. 2008;156(6):1163-1169.↵
- Gorman, Christine, “A Candidate’s Racing Heart,” TIME, Sunday, Dec. 12, 1999. http://www.time.com/time/printout/0,8816,35831,99.html↵
- VIDEO 3: Me Being Cardioverted YouTube video; Last accessed February 22, 2013; URL: http://www.youtube.com/watch?v=2nsN0vdXZuY&feature=fvw.↵