I'm curious if any of you have seen a bad case of one of these. Saw a patient today with this. Really wide QRS (130-105), going into an Afib 110's-120's, intermittently switching back into what looked like an accelerated nodal rhythm is the 80's. The Fib seemed to respond to the Mag we were giving as boluses, and we considered a Mag drip . . . though were not sure (cards rec's were no amio, shock if needed, pace if needed) Anyone seen one like this?