I'm really interested to read this thread. I went to a cardiologist wondering if I had POTS as after years of intermittent dizziness /lightheaded I noticed that my HR was going up a lot when I stood up. Sometimes it was sustained past +30bpm for 10 minutes but often it dropped back to normal. Cardiologist diagnosed me as mild dysautonomia and mild mitral valve prolapse. I passed my stress test. He suggested I start back at exercise, but go lightly so I bought myself a pulse watch thing. And a proper BP monitor. It's been illuminating!! Now I'm realising that my HR randomly goes high for no reason. Like up to 100 when lying down and can be 70 standing still. My Bp averages about 95/60, at times it's up to 130 but I think diastolic is always 60 or lower. My BP at doctors is always normal but my cardiologist did say that I could just be getting anxious at appointments. So it's likely I have low BP and totally random HR??? Is that dysautonomia or something else??? I had a low of 38bpm on my holter but otherwise nothing too worrying. I noticed my hr went down 45 standing up the other day. I'm not wearing now as it's freaking me out!!!