@dejurgen Thanks for the response. Some real good stuff there that I hadn't thought about.
As for the heart rate, it is usually between say 80-95 but can go a fair bit higher so I wouldn't say I am locked in this range just that a couple years back when I was much worse my HR would be frequently 100+ and much higher if I gad to stand.
For the aGPC I wish I could remember better, it was around 5yrs ago now when I had no idea what was going on. I am pretty sure it was plain aGPC I took although there was a small chance it was parasymPlus although I am pretty sure I only started experimenting with it afterwards. As for dosage and time after I noticed response I couldn't say. It was probably less than an hour after dosage.
When I say I went into remmision for thirty minutes, I cannot say for sure as I spent those 30mins in a chair at my computer. All I know is my constant heart pounding that has been with me for 9yrs (at that point 4/5yrs) stopped, and I felt relaxed, not overly so, just like a normal person would, instead of wired and unrelaxed that I feel all the time. So for those 30mins (or so, I can't remember exactly how long it lasted) sitting in my chair playing video games I had no symptoms and thought to myself I had cracked it. I had being reading Dr Diana Driscoll at the time and I didn't even know I had POTS I was just looking at the gastroparesis angle.
Of course subsequent doses never worked, I tried high and low. Even recently I started taking it again with piracetam but stopped after a few days after getting massive headache.
For the carb thing your explanation makes a lot of sense to me. The gut one I am not so sure it is a problem in me but it would be super hard to tell as the gut can cause many non gut symptoms. I don't get blood in my stool after carbs. My symptoms appear to be more inline with my BG. I took regular measurements when I was experimenting with high carb and my symptom severity more or less followed my postprandial BG. Symptoms elevate and reach a peak around 1-1.5hrs in then slowly decrease to baseline over the few hrs.
Overloading with energy after a meal, of which the cell / mitochondria cannot utilize due to low O2 makes a lot of sense especially considering that glucose cannot be as easily dealt with as fat and also various insulin responses.
One thing I have noticed is when I get into ketosis, certain POTS symptoms get significantly worse, particularly rapid heart rate and weakness, poorer tolerance to standing. I have interpreted this to be due to adrenal gland stuggling without carbs. I figure my adrenals are working hard to keep me in sympathetic dominance to help blood flow. As far as I am aware adrenals need high carbs/vit C. Without them I produce less adrenaline and this causes vasodialation poor blood flow, and rapid heart.
Anyway, I have noticed though I am not 100% certain that when I cant take this anymore and eat some carbs (say 100g chocolate bar 50g carbs) these symptoms go away however I don't notice the usual response I get to carbs. This suggests in me it is not a gut issue but like you say, energy overload as if my liver is depleted in carbs due to ketosis, taking in 50 or so grams would go straight to filling up glycogen reserves and the fat of the meal can be dealt with easily.
I had the perfect opportunity to test this last night as I had hit the ketosis adrenal problem again so I ate a bunch of chocolate (over 100g carbs) and unfortunately this just lead to the usual post carb symptoms which died down after 3hrs, however after those 3hrs no more ketosis adrenal problem. Perhaps the energy intake was just too high.
One thing that is puzzling me though is that I have previously found improvement in things that boost Pyruvate Dehydrogenase activity. I noticed a significant improvement after taking thiamine with meal a couple of years ago. I seem to have maintained that improvement with need for thiamine anymore (perhaps correcting a deficiency as my diet 6 months before I go very bad was very low B1).
I have also noticed improvement in carbs tolerance when taking MCT oil with carbs. The logic was that if PDH is problematic then I could skirt the issue by providing acetyl CoA to the liver in the presence of carbs via fat. If LCT are used they bypass the liver and insulin shoves them in fat however MCTs are metabolised with glucose in the liver.
I intend to try MCT + Carbs again today. I noticed an improvement doing this but that goes against your energy overload theory does it not. The only thing I can think how it would go with your theory is that the MCT provides NAD+ to help mop up problematic NADH/lactate accumulation. Perhaps forcing PDH activiy increase mito affenity for O2?
I should note that on day one of doing this I felt great post meal (it took about an hour to kick in). Whilst I continued to do it afterwards and experienced improved tolerance to carbs, I never reclaimed that great feeling. I have since learnt that this has happened in over people and it is though that you give your (brain?) cells a ton of energy as your body doesn't expect both high ketones and high glucose at the same time however it quickly adjusts for this. Still, shouldn't energy overload be a problem? Perhaps it is different in the brain as I do not get many brain symptoms.
This post is super long but I will just quickly say that the HBOT idea does make a lot of sense however I thing that
@Hip posted that it is possible that O2 gets into the blood beyond 100% saturation. I guess free O2. Which should cause big problems with ROS. I think this is the supossed anti pathogen effect of HBOT.