Not too long ago, EM-> pain became a thing. Same with EM—> CCM. What else could we do? I feel like cardiology would be realistic. Who decides? Who do we talk to?
It would have to be ABIM and ABEM co-sponsoring a board application to ABMS.
Generally it is preceded by a long period (years to decades) of people forging their own, very uncertain, at best partially recognized path. I am most familiar with how the CCM path worked out, less so with pain.
The initial application to ABMS for an emergency medicine board was actually for a board of emergency medicine and critical care. It did not go through and by the time EM leadership re-applied, surgery, anesthesia, and IM had pushed through their own critical care boards. What followed was decades of EM trained folks doing the fellowships but not being board certified. Some would go on to sit for the European diploma in critical care (EDIC/ESICM) which would certify people trained anywhere as long as they were appropriately trained and passed their exams. Some of these folks gained some prominence in the field (eg Scott Weingart). Then there was a general recognition of several facts that really helped push through a formal pathway for EM trained folks to become board certified:
1) National recognition of a shortage of CCM trained folks (eg Leapfrog report on ICU staffing)
2) General decline in fill rates for CCM fellowships in surgery/anesthesia/IM
Without those two things, board eligibility for EM trained intensivists probably wouldn't exist to this day. One could foresee an alternative future where we reached this point just by virtue of more and more emergency physicians reaching prominence in the critical care world, taking more leadership positions in hospitals and critical care organizations, but this seems less likely. The uncertainty of building a career on a not-quite-recognized pathway pushed away a lot of people, so I doubt we would ever reach a critical mass in the specialty without those outside factors helping.
Unfortunately this doesn't seem to be the case in cardiology. They have no problem filling their spots with IM applicants. So while ABEM would probably be game, I don't see why ABIM would be interested. The only positive factor we have is that there are a few emergency physicians who have earned some fame in the cardiology world (a couple of the ECG gurus come to mind), but there are no emergency physicians practicing in a primarily cardiology/cardiology adjacent space (like there were leading up to CCM recognition) nor are there (to my knowledge, though I could be wrong) famous EM trained cardiology researchers a la Manny Rivers (who was of course EM/IM trained).