Just a note, although a medical professional can correct me if I am wrong- An AED will not work on someone dealing with an episode of A Fib. I believe they only generate a shock on those in V Tach, V Fib, or Cardiac Arrest. I believe the AED will pick up on the type of arrhythmia present and will only shock if it is a ventricular arrhythmia or cardiac arrest.
Cardioversion (a milder shock that is given manually) is used to treat A Fib obviously, which it sounds like Peverley received at the hospital or in the ambulance.
This is my understanding, but I may be wrong. AEDs are obviously very important and necessary regardless.
edit- got some support info from Dr Love for what it is worth.
http://www.justanswer.com/medical/6e...tion-vfib.html