PFA is currently only approved for a simple PVI, or pulmonary vein isolation. I am not an expert in this field, but it seems to me that, after three previous ablations, the area around your pulmonary veins should be well scarred. So, you may have another focus, or re-entrant, for the new signal, and it won't be in a place where PFA can be applied. Again, maybe I'm not up to date and it is now approved for other areas of the left atrium. Last I knew, it was only to be used at the pulmonary vein ostia, or where they empty into the left atrium's posterior wall. So I'm curious as to how your EP knows that he/she can use PFA....for a fourth application.