Can POTS come and go? Variability of POTS degree with PEM

I’ve previously considered myself to be unlikely to have POTS. I can be almost normally active on very good days (paid for later).
But a recent experience of tachycardia (110-135bpm when normal resting was 58-70) for days on end, and repeated instances in the days before and after that of sitting (hunched or reclining) with 70s bpm, stand (just calmly standing) and within a minute it’s over 120, up to 140s and a brief 150s... sounds like POTS. But it’s not always the case. Does that mean it’s not POTS?
Or is it possible to have POTS only in PEM?

 

In my experience, as a non medical person, yes.

When I overdo things I seem to enter some form of pyßiological crash state several hours before I notice anythings wrong, before PEM.

One of the signs of this is my HR climbs considerably even lying down at rest, and can often exceed 130 if I have the temerity to stand up.

This state persists for a few to several days, during subsequent PEM.

When not in this physiological crash state my HR is normal.

 

n=1
I have mild POTS all the time but it gets much worse during PEM. So I wouldn't be surprised if someone had it only during PEM.

I've never had the persistent tachy lying down you describe and that doesn't sound like typical POTS because, well, you're lying down. Though during PEM my resting HR is up about 10 beats or so.

Which doesn't mean the two aren't linked. It's possible that our ME-POTS isn't really "normal" POTS at all but just another annoying ME manifestation that looks similar to POTS. And your supine tachy could be just another such annoying ME manifestation, too. But who can know for sure?

If your HR playing up is something new for you and you haven't had it checked out, could be a good idea to do so. Not every new symptom we get is due to ME.

 

For me it is definitely variable. It usually gets bad for a time, then as long as I manage it, doesn't get bad again for a while. Heat can always do it. It is hard to know how much is POTS, and how much is PEM, both make me feel so ill, and overstimulated.

 

In my experience, its severity fluctuates with the severity of my overall condition and it is worsened by PEM.

 

It is variable. It seems to depend on exertion, temperature, hydration, salt intake. In my experience eating food I'm intolerant to also triggers increased heart rate.

 

n=1. when i was younger & mostly healthy, i had episodes of POTS, especially in hot summer weather.

more recently, a cardiologist who has some knowledge of POTS, reassured me that POTS can fluctuate in some patients - especially in hot summer weather - and recommended saline infusions if the symptoms became too severe.

currently, with cold winter weather, my POTS is worse than usual.