Would you please provide the ranges for your FT3 and FT4?
You haven't taken thyroid meds for 30 years? Have you monitored your levels at all in that time? Were you ever tested for TSI?
I have a right bundle bunch block , left hemi block , left chamber hyper connetic, and have extra beats....
30 years off meds
High TPO and low TSH may sound like Hashimoto's flare up (subclinical hyper stage).
Ask your doctor if you can take Ibuprofen- it should help with symptoms which interfere with singing or talking (Hashimoto's sometimes called the artritis of thyroid)
What are the ranges on your FT3 and FT4? Ranges vary lab to lab, so you have to report them with results.
How long have you been off meds?
What's your heart issue?