Great topic. I get the same thing sometimes. I don't entirely know what causes it either. Same kinds of triggers as you listed for me. Some days it happens, some days it doesn't. I think my underlying stress level could be part of it - higher underlying stress = more chance of the tachycardia. I do know that a 24 hour monitor wasn't always long enough to pick up the problem in the test since it wasn't happening every day for me. I also know that sometimes mine are normal or "sinus" tachycardia and sometimes they are an arrhythmia called an SVT: supra ventricular tachycardia. I'm on two types of medication for it - one particularly because of the SVTs. I'm not sure yet how much the meds help.

Oh, I just saw that your post lists paroxysmal SVT, so you know about that already. That's what I get. A couple of years ago I saw a YouTube video by a lady who had been able to stop the SVTs. I can't recall all she said. I think she said she had no caffeine amongst other things.