How you prepare

Cardioversion procedures are usually scheduled in advance. However, if your symptoms are severe, you may need to have cardioversion in an emergency setting.

You typically can't eat or drink anything for about eight hours before your procedure. Your doctor will tell you whether to 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. Blood clots can break free by cardioversion, causing life-threatening complications. Your doctor will decide whether you need a transesophageal echocardiogram before cardioversion.

If your doctor finds blood clots, your cardioversion procedure will be delayed for three to four weeks. During that time, you'll take blood-thinning medications to reduce your risk of complications.