is a HR of 140 for 12 hours dangerous??

[YZ1911]

i am 27/m and i am 6'0 220 pounds. couple of days ago i had a bad tooth infection and went to the dentist. as i was leaving the office,i started to get very dizzy and sat down on the steps. my ears started to ring badly and my vision became very blurry. i stood up and walked around and felt better. i went back inside and gor my blood pressure checked and it was just 80/40. the dentist sent me to the ER. an hour later i got to the ER and my blood pressure was 107/66 but my heart rate was 140. i had an EKG done and it said sinus tachycardia with a rightward axis,otherwise it was fine. i was in observation on a heart monitor and i got saline and antibiotics for the tooth infection. for 12 hours my heart rate was from 136-142 and it did not get lower. i want to know,is this dangerous? was my heart beating so fast and i almost fainted because of the tooth infection or was it something else? i have not been to a Dr. since 1996,so i do not know what my health is. can anyone tell me,was this incident normal?

[YZ1911]

thanks for the reply. i did not really have a fever. i think it was just 99.0. i did see a doctor in the ER,this was the first time since 1996 that i had seen one. my heart is ok right now,the abscess is still there and i will have to take care of it,i just wanted to know if my heart could be damaged going that fast for a long time,but you said that a healthy heart can handle it so i will not worry about any damage to the heart muscle.

[is_something_wrong]

It's quite obvious that your heart rate was elevated to compensate for a far too low blood pressure. Even with this compensation, your blood pressure was borderline low.

Did you have a fever? If yes, how bad was it? Fever will both dilate blood vessels and increase heart rate.

My guess is that you almost fainted because the blood pressure was low.

The rightward axis is normal with a heart rate in the 130s. For some reason, the axis turns rightwards with increasing heart rate up to 130-140, then it usually turns leftwards again.

I'm a bit confused about what you say about seeing doctors, I hope you saw a doctor at the emergency room? Is your heart rate lower now? Is your infection under control?

Dental infections may affect structures of the heart and it's important that you keep in touch with your doctor until this problem is solved.

A heart rate of 140 for 12 hours is of course not normal. Not necessarily life threatening (a healthy heart can usually handle that) but a cause must be found, and if you have/had a severe infection, it's really important that this is taken care of.