Hi there, my name is Karen, I'm 32 yo and I've been a member here on Connect for awhile now, but I usually stay within the neurology boards due to my conditions. However, for the last year or so I've developed chronic (inappropriate, I guess is the correct term?) sinus tachycardia w/ regular PVCs etc. My resting heart rate stays around 120+ and my BP is either normal or somewhat low. I get short of breath and lightheaded a lot while doing nothing, I'm fatigued all the time, constantly feeling like I just ran a half marathon, when in reality all I was doing was standing or sitting. I do have orthostatic hypotension, but this seems to be very different and "out of nowhere." I see a chiropractor regularly so I know that my vagus nerve is not a problem here. My Dr prescribed metoprolol 25mg in the past, but it didn't really seem to help. I got represcribed it today, so I plan to give it another shot. But, I'm really wondering about what could possibly be causing this? Anxiety and stress have both been ruled out. I'm frustrated bc I used to be really active and I'm having a hard time functioning at work / home w/o wanting to sleep or rest all the time. I want to be active again and for my quality of life to increase. I know a lot of it's all in your perspective, but even still... Any thoughts? Thanks ya'll.