Cardiac Rehab - Getting Into

I just began my nursing career this Augast 2014 on a Cardiac Progressive Care Unit. We do see other patients, but mostly cardiac. I do like it. I do still have lots to learn, and need to practice IV starts though. I was thinking about the future recently and where do I want to go. Since I like cardiac and I like fitness, I was thinking cardiac rehab. I would like to work with patients on preventative care. Is cardiac or cardiac-pulmonary rehab still a nursing specialty? How would I get into this specialty? I plant to get 2-4 years experience on my floor first. Any insights would be greatly appreciated. Thanks!