What To Expect Before Cardioversion

You usually can't have any food or drinks for about 12 hours before the cardioversion (as your doctor advises).

You're at increased risk for dangerous blood clots during and after a cardioversion. This is because the procedure can dislodge blood clots that may have formed due to an arrhythmia. Your doctor may prescribe anticlotting medicine to prevent these clots. People often take this medicine for several weeks before the procedure and for several weeks to months after the procedure.

To find out whether you need anticlotting medicine, your doctor may have you undergo a transesophageal echocardiogram (TEE) before the cardioversion. A TEE is a special type of ultrasound. An ultrasound is a test that uses sound waves to look at the organs and structures in the body.

You will be given medicine to make you sleep during the TEE. A special wand that transmits sound waves is put on the end of a tube. The tube is put down your throat into your esophagus (the passage from your mouth to your stomach). The tube is placed close to your heart, and the sound waves create pictures of your heart. Your doctor will look at these pictures to see whether you have any blood clots.

The TEE will be scheduled for the same time as the cardioversion or just before the procedure. If blood clots are found, your cardioversion may be put off for a few weeks. During this time, you will take anticlotting medicine.

Even if no blood clots are found, you will be given anticlotting medicine through a vein during the cardioversion. You also will take medicine after the procedure to prevent blood clots.

Before a cardioversion, you're given medicine to make you sleep through the procedure. This medicine can affect your awareness when you wake up. You will need to arrange for someone to drive you home after the procedure.