I always mention that when I'm well enough to exert myself in any way, I have some kind of crash that feels like something is going after my heart.
Also when he was titrating me up on thyroid meds I realized that the meds made me more "heart tired." My description for it. They must have been speeding my heart up too much and making it work harder.
It's like some of the times my crash fatigue actually originates from my heart especially when I have been pushing myself to do too much. I think and fear that whatever caused the ME/CFS, is causing some damage to my heart as well.
Is that how you feel, @lukesirde?