Beta blockers block the effects of adrenaline on the heart. This is why you are having difficulty getting your heart rate to increase. In addition, feelings of fatigue are common with all classes of beta blockers. Carvedilol, or Coreg, has slightly more potent blood pressure effects but are otherwise fairly similar to metoprolol. Hope that this helps.
I should probably note that it is the coreg 10mg time release that I am referring to.
Is there anything wrong with 145bpm? it's certainly not ridiculously high.
After my triple bypass surgery my heart rate would quickly jump from 90 (standing) to 186 during the exercise classes at rehab. I say 'jump' but it took 10-15 seconds if I really worked hard, such as very fast star jumps. When stopping the exercise my heart reduced to 90 in less than 30 seconds. There was no chest pains and I felt great. My cardiologist said it shows a healthy heart providing demands during cardio-vascular exercises and it was nothing to be concerned about.
That is encouraging. Mostly, I think the concern was that it made that jump within seconds. My cardiologist thinks it only nerves as the nuclear revealed that my heart is "perfectly normal" in his words. Plus it really freaks me out.
On the other hand, I decided to try the 10mg Coreg CR and it is not working. My blood pressure has gone from an average of 118/75 to an average of 130/80. Admittedly, that's still not bad, but it is kind of odd that it increased. Plus the coreg cr is 120 dollars for one month, I can't imagine how much the 20 mg costs. So it looks like I'll end up back on the metoprolol. Hopefully the tiredness will go away. The ramipril was working just fine, but the anxiety, especially in the mornings was too much and would cause my bp to jump up to 150/100.
That is a good recovery rate. Mine never recovers that fast, but usually gets around 115 in a minute from 180ish.
I hav been on metoprolol for 10 years, due to PVC:s, PAC:s and runs of them. The first year I got wery tired, my resting pulse was not so low as yours, perhaps 55-60, but I was never able to stay up longer than nine o´clock in the evening. Then I fell asleep. When I was at a party I laid to rest on some sofa and in 15 minutes past nine I slept :-)
That side effect eventually went away and after the first year my resting pulse was up again and the fatigue was gone. However its still harder for me to get my pulse up when I exersise than before the BB.