Crossroads- Hospital CNA or Dementia Care?

I will complete my ADN prerequisites this fall semester taking the highest level courses and I have maintained a 4.0 GPA. I aspire to be a cardiac nurse in a hospital setting and plan to continue my education all the way to a doctorate in nursing administration or nurse practitioner (I'll decide on that one when my experience tells me which I would rather pursue). I've worked very hard to get to the point I am at, my family has sacrificed a lot for this opportunity and my motivation to become a cardiac nurse is strongly rooted in my own personal experiences (something that I might share in another post).

Last fall, I took a part time CNA position at a dementia unit over the hospitals, correctly figuring that the facility would provide me with more opportunities to develop my leadership skills and personality as a CNA (my last profession was as a mechanic where I did a lot of solitary work in a very hostile, masculine environment). The problem is that a few months ago I was discharged for bogus reasoning and its obvious to me and my former coworkers that it was in retaliation for an incident in which I had to go above the facility director and nurse because they were purposely ignoring a staffing problem that endangered the care of the residents.

Recently I have begun to apply for open CNA positions at hospitals and I have been dismissed as a candidate early in the process. I don't know if this discharge lacking merit (unemployment did an investigation, the employer brought forth additional false charges that they failed to substantiate and concluded I did not commit any misconduct) is hindering my prospects or if I simply do not fit a strict profile they look for in candidates.

This has forced me to consider continuing down the dementia care path. I am looking for insights as to how I could make this area of nursing assistant an asset to my aspirations to be a cardiac RN.