Good luck with that. If the medical group you are a part of is in their regional, statewide or a country wide HIE, you'd have to check with every connected partner to see what other systems may have queried for your data and potentially have copies as well.

You typically won't have your data in too many other systems unless you are hopping between different medical groups/hospitals. There's just a possibility that the above could happen because, seeing and making the sausage, I wouldn't trust anyone to be able to tell me who has seen my health records.