Frustrated with Cardiologist's Suggestions

I would ask them what their plan is if that doesn't work. And I would call them back in a week or two weeks and tell them that it didn't work. Obviously try what they recommended, but if you don't see an improvement you should let them know. And if they suggest it again, ask them for documentation that they are refusing to test or treat you and that they are giving you the same suggestions they gave last time. I promise you they will sing a different tune in a heartbeat