Not sure what the exact chances for a DO in this situation would be. I would tend to agree with the above comment.
The Step 1 score is all right...not going to be helpful but wouldn't keep you out at all. In fact, a lot of cardiology programs don't even look at the Step scores...I mean some don't ask/require that they be sent at all.
Your best chance may be a DO cardiology fellowship...don't they have their own?
The problem is as described above...the higher tier IM allopathic residencies have plenty of applicants so they aren't necessarily looking for DO's to fill their spots, and some don't really take DO's much, or at all. Plus some of these type IM residencies might have step score screening where they mostly or only look at people who got 220 or 230 on the Step I. And if you aren't coming from one of those upper tier IM residencies, then getting an allo cards fellowship spot is going to be harder...plus then it will be harder b/c you are a DO...and harder b/c you don't have a the high step score (not that yours is bad...it's just not high enough to make you stand out among cards applicants).
If you do a allopathic residency, would that make you ineligible for DO cardiology fellowships? If it would, I'd think twice about matching into an allopathic medicine program unless you are very willing to consider other allopathic specialties. I know several people who started out wanting cards but switched to things like endocrine (can still be a lipid/cholesterol specialist, for example) or renal or pulm/critical care.
