Umm youre talking about cardio conversion. I have had three incidents where I had to be shocked. Each time it took three trys to get me going again. The worse part for me was the burns covering my chest. They hurt!

The secopnd last time i was in emerg they had to kill me twice to get my heart to slow down it was either that or i was going to explode they finaly got my heart to slow down last time i checked it was 63 so yes it works

my experience tells me that when your in a-fib or v-tach cardioversion is a go to treatment. It really isn't just that cut and dried tho.

how frequently is cardioversion needed for atrial fibrillation?

it has worked for me....more than a few times.