I have had both. The Tee is a trans esophageal procedure. It is really nothing to worry about because you are in the very best place you could be during the procedure with the Dr and his crew knowing exactly what to do if something happens which chances are won’t. The cardioversion also is nothing to worry about and brings your rhythm back to normal. You’ll feel so much better. Please don’t worry, both procedures will be simple for you. You will not even have any post op symptoms. Maybe a small sore throat which goes away quickly. I also was so worried before I had them done. But I assure there is no need to. Best of luck.