Be willing to try and feel the panic attacks (easier said than done) but when you feel it starting, be with the feeling (allow the mind to continue the commentary) but put your focus on the feeling...
After awhile (maybe the first time) you will notice that it is the ''thinking about having a panic attack, and what it could do'' is much worse than actually just feeling it....when you just feel it, it will not have the same affect to when you are fighting against it, or trying to ''resolve it''...
You could always start with unpleasant feelings, then work on panic attacks...no need to dive right in at the deep end at the start