So glad you went ahead with the muscle biopsy. No matter the results, at least you'll know where you stand in this regard. Please update us when you get results.

The cardio tests for POTS is important. there are many treatment options for POTS, so again, good you have this coming up...as you are in need of some relief for your symptoms. Can you describe what is going on (cardio)? Do you have drops in BP upon standing? Did the cardio do any orthostatic testing (BP while laying down, sitting up and standing)? What about heart rate...any increases (racing with exertion)? And what about the opposite...slow heart rate?

Did they give you any idea of what tests they will be running...like tilt table, 24 hour BP monitor, holter monitor, etc?

Sorry for all the questions...just trying to get an idea of what you're dealing with, so I can offer suggestions. I have numerous (and severe) autonomic dysfunction and have learned over last 20 years how to deal with many of the symptoms.