Twice I have been to the ER (different hospitals each time), once to my primary care, and once to a cardiologist ordering ultrasounds. The only things the ERs have told me are:
1. I was severely dehydrated the first time, which after they injected 2 liters, I felt perfect for a couple hours. It also lowered my heartrate to under 100 (it was originally 144).
2. I have high blood pressure; the 2nd hospital prescribed me lisinopril, on top of the metoprolol my primary care prescribed me. As a result, my blood pressure has dropped.
Otherwise, all the other tests they ran on me turned out healthy results, yet I still feel chest pains in the center and left side of my chest every now and then; the condition has been improving, but it still happens. 1,200 mg of Guaifenesin once ever 12 hours seems to help a lot, as well as 3 mg of Ativan a day (I have an anxiety disorder which takes its physical toll). However, all this still worries me, especially since I now occasionally feel left arm pains which I've heard, when coupled with everything else I've mentioned, should be particularly worrying. But as I said, even those are momentary.
Also, when I started Metoprolol, I felt mild symptoms for a couple hours before they went away. After my doc upped me to taking it twice a day, after I took it the 2nd time, I felt horrid symptoms that did go away eventually. Then I went to take it the 1st time the next day, I felt significantly less severe symptoms, but they cued me to