I'm currently on the interview trail and can give you some insight. UofC is an excellent program, but certainly not a top tier program for IM. Their cardiology department is more basic science oriented and has about the same reputation as their IM department. To get into a top tier cardiology fellowship you likely need: a) chief residency at 2nd/3rd tier b) top tier IM c) MD/PhD d) total package at 2nd/3rd tier (good LOR, publications/research, high class rank, etc). If you go to Hopkins, Duke, etc., then it is far easier to match into any cardiology fellowship. Of course that is if you want a top tier spot, or excellent chances at 2nd/3rd tier. I'm sure applicants from UofC do extremely well, and you would have no problem matching at an excellent program. So far, on the trail I have seen applicants from Penn, Columbia, UTSW, UVA, Beth Israel, Duke, Yale, Brigham, BU, Cleveland Clinic, among others. As you can see there is quite a mix of programs. Ultimately, you need to go where you will do well, since a poor performance at any program will ruin your chances. Good luck.