How you prepare
By Mayo Clinic staffCardioversion procedures are usually scheduled in advance, although if your symptoms are severe, you may need to have cardioversion in an emergency setting.
You typically can't eat or drink anything for 12 hours before your procedure. Your doctor will tell you whether you should take any of your regular medications before your procedure. If you do take medications before your procedure, sip only enough water to swallow your pills.
Before cardioversion, you may have a procedure called a transesophageal echocardiogram to check for blood clots in your heart, which can be dislodged by cardioversion, causing life-threatening complications. Your cardiologist will decide if you need a transesophageal echocardiogram before cardioversion.
In a transesophageal echocardiogram, your throat is numbed and a flexible tube containing a transducer is guided down your throat and into your esophagus, which connects your mouth to your stomach. From there, the transducer can obtain more-detailed images of your heart so that your doctor can check for blood clots.
If your doctor finds blood clots, your cardioversion procedure will be delayed for a few weeks while you take blood-thinning medications to reduce your risk of complications.
- Cardioversion. National Heart, Lung, and Blood Institute. http://www.nhlbi.nih.gov/health/dci/Diseases/crv/crv_all.html. Accessed March 4, 2011.
- Wann LS, et al. 2011 ACCF/AHA/HRS focused update on the management of patients with atrial fibrillation (updating the 2006 guideline): A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation. In press. Accessed March 4, 2011.
- Podrid PJ. Cardioversion for specific arrhythmias. http://www.uptodate.com/home/index.html. Accessed March 4, 2011.
- Podrid PJ. Basic principles and technique for cardioversion and defibrillation. http://www.uptodate.com/home/index.html. Accessed March 4, 2011.
- Nagarakanti R, et al. Dabigatran versus warfarin in patients with atrial fibrillation: An analysis of patients undergoing cardioversion. Circulation. 2011;123:131.


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