Cardioversion is an electrical reset of the heart's SA node (sino atrial node, from where the electrical impulse for the four chambers to beat issues. The patient is attended to by an ER physician, a nurse, and often by an RT (respiratory therapist to monitor your breathing while the procedure is undertaken...you'll be unconscious.) You will possibly be given adenosine to slow the heart rate and to reveal the nature of the arrythmia that is being depicted on a concurrent ECG. That part of the experience is not fun, but it's over inside of 12 seconds or so (I can explain this if anyone is interested). Once the true nature of the arrhythmia is established (ie that it is truly AF and not flutter), they'll now how to place the shock paddles and sensors. Then, you are given propofol in your IV that was inserted when you presented to the ER and were taken inside. You'll be gone inside of 20 seconds, usually, although I have a funny story about that. Then, while you're out, they can shock your heart only three times, each time raising the joules to increase the jolt if your heart stays in arrythmia. About two minutes later, you come to and hopefully you can hear the welcome beap, beap, beap and everyone is smiling.

In summary, it is a series of shocks while you are unconscious gratis a propofol, the same stuff they administer for endoscopy, trans-esophageal echocardiograms, and for colonoscopy procedures. If one of the three shocks works, you're out of the ER and on the way home after a short period of observation, maybe 30 minutes to an hour on your back.