Doozlygirl, this symptom has really just gotten worst since this last episode I had. I don't have any triggers, my heart rate stays at around 45 when resting, and so i just get so weak that i just pass out wherever I am, I used to just try and get up early and just never sit down so I could get things done, because if i sit down my HR would drop and i would pass out , but now I can't do that since I have gotten worst I have to sit alot during the day because my HR goes to high when standing to do simple things. Sitting my heart rate is 40-50 BPM i stand and it jumps to over 100 and just keeps climbing if i do anything, it gets up to 170 if i keep going, especially when I am doing dishes. so besides just my bradycardia i can't think of anything else that would cause mine, I haven't been diagnosed "POTS" I haven't had much testing from a qualified doctor. I just know resting my hr is too low and standing my hr is too high and causes me to faint either way. this last time last wednesday my HR was low and i was weak and started having my neck, head, and shoulder pain so I got up to leave church and almost passed out right before sitting in a chair while my husband got the kiddos, then i was ok just weak i was talking to one of the pastors and drank some water and then collapsed my HR dropped too low and i fainted and quit breathing temporarily. since then my symptoms are exaggerated. Sorry I hope i didn't scare anyone but seeing this is a forum where this happens I hope i didn't offend anyone. so, I don't know about triggers but I don't understand much about this myself, I have had all of these symptoms some since birth and others started at 6 and others at 12. I would think however that it is just your low HR, because thats how it is with me, My respirations drop because it doesn't seem like i need to breathe much and i just drift off. sorry I hope this helps I am just as if not more confused than you.