Hey, Brady is strong, healthy, and if Andre can manage to hypnotize an entire town into thinking terrible murders are going on, with dead not really dead, but on some island where he also managed to create an exact replica of the city of Salem, the homes, bldgs., and furniture inside........then heck, Brady can sure easily survive another heart transplant (after all, he drinks Salem water, the hospital staff washes in it, etc. etc. )
Plus don't forget, expert heart surgeon Valerie is now on staff at Salem hospital. She saved Abe, right?