I am saddened to read of your dx and in truth I do not know a lot re this type of myopathy but I have done some research and will post a few links for you.
Cleveland Clinic has the reputation of being the # 1 heart hospital in the USA and I am thinking perhaps they could help you. Right behind them is Mayo Clinic in Rochester. Don't give up in finding the answers you are looking for.
My prayers are with you and do feel comfortable posting here even if it is just to vent or looking for support.
Wishing you fair winds and following seas,