Do you have any options to get the mayo cardiologist or the mayo kidney doctor to “clear” his heart and the blockage for a kidney transplant (be willing to do kidney without fixing heart). As is. (If they agree with the other cardiologist it’s not a risk). This would seem possibly the best solution if they do think it is not a risk. However if they do think it is a risk then let them fix it. I know you have talked to a nurse but can somebody else help you get those answers such as the doctors.