I feel that both parties to this abrupt parting were essentially right in their orientation. You have the right, perhaps even the duty, to seek and to acquire the best care for yourself. On the other hand, the cardiologist had already informed you of her opinion, and couldn't very well listen to another and accept that as a better one. If she did, she would be somewhat diminished in competency in your eyes, in which case you'd almost certainly seek the services of the other cardiologist. There could be no winners in returning to an original informer and confronting her with a contrary opinion.

LOL, you don't tell a doctor about what another doctor said that might be different from their opinion. Two Mayo Clinic doctors advice me to get 2 to 3 opinions for any major procedure. Mayo advice saved me from an extreme procedure for my cancer. The first 2 doctors had arrogant attitudes.