Quick question about heart rate

[Worrier13]

Hello. This question has been on my mind for about six months. When I first got anxiety they tested my heart with all kinds of monitors and tests for two whole months (this was a year ago). They did find (only once during a 48h holter test) one slight umm..weird thing? I don't know what it was, something about tachyrdia. And my cardiologist gave me propanol (15mg, so a really small dose) but now I haven't heard from him in long time and he said it wasn't serious and could be because of anxiety. I stopped taking my medicine a few weeks ago since it didnt do anything to my blood pressure or pulse. So well anyway, what Im wondering is: my pulse is always 90-120, even when Im sleeping. It does not really disturb me or anything but it can't be healthy right? My bloodpressure is always 110/70 so quite low(ish). Im 20 years old, girl, 50kg and 166cm. I smoke (well snus, but I guess we only have that here in Sweden). I also googled that high heart rate causes early death.. Is there any way to stop it and is it really that dangerous? I'm starting to really scare myself with this and Im measuring my bloodpressure+pulse multiple times a day and it's always the same, even when im fully rested. And the holter showed that it's that high while sleeping too. My heart rate used to be 50 :(. Sorry if this post seems weird, I wrote it on my phone. Advice, please!

[mummyanxious]

Have they done any blood tests? I think anaemia and thyroid issues can cause fast pulse.
Did your dr take you off the tablets? Probably best to speak with them again.

[Worrier13]

Hi and thanks for your reply :) yes, they did all kinds of tests and multiple bloodtests since I was so out of control with HA, I could never believe that with all my horrible symtoms it could be just cause of anxiety but it was. My thyroid levels were low at one point (eventhough it should be high levels that causes rapid heartbeat), they're fine now. Tests etc that I've had in the past six months: every bloodtest possible, brain, neck & chest mri, heart ultrasound, head/brain ct scan, lumbar puncture, 3xfull eye examination by eyedoctor, 6xneurological exams, eeg, 7xekg, 3x48h holter, 1 week thumb ekg, 1 week holter, that thing where you exercise and they measure your heart and well I probably forgot a lot. So I really should be physically healthy but this heart rate scares me alot, it didnt just to but now that I read that 'early death by rapid heartbeat' thing.. I cant stop thinking about it. Yes, I stopped my medication by myself but it really didnt do _anything_. I know that my nicotine use is one reason but it didnt use to cause this kind of pulse. Just how dangerous is this? :/

[mummyanxious]

I do think you should go back to your dr and speak about it and stopping your meds. They may be able to give you something different as some don't work in some people. But did you say you've got low bp? So they probably wouldn't want you on a big dose of anything because of lowering your bp.
Only they can really tell you if its dangerous. But look at all the tests you've had! Wow all those clear tests should be a really good sign for you.