Excellent post again.
I have a friend who's daughter had attacks of massively rapid heart beat caused, they thought, by overgrowth of some trigger points in her heart. She's been through ablation [burning off the extra trigger points] after which she suffered pots like symptoms where her blood pressure dropped radically. Now her trigger points have regrown and the fainting has stopped, but the periodic heart racing has reasserted itself. To my mind it seems that her racing heart is an adaptation to sudden moments of low blood pressure. Maybe the extra trigger points were a red herring? Maybe they have grown there as an adaptation?
Either way, POTS has never been mentioned as a diagnosis. Never been considered.
I was thinking Paula, you may be interested to add this example to your knowledge. Sorry to have not spoken more specifically [in medical terms] but I've only had very cursory conversations with her. Her mum is not inclined to use homeopathy. Before she was diagnosed with the extra trigger points in the heart [and went through surgery] I had managed on one occasion to treat her with aconite 10M [because it happened in my house], which did revive her very well.
I'll talk to you more on this at some point and will try to find out what the diagnosis actually was, as it may be that this will be a factor in some of the PoTs cases you see.