I recently went through a frightening period of constant tachycardia (sleeping and at rest) for three weeks. Started out of a clear blue sky. Monitored in the ER for three hours (regular cardio sent me there after I called his office), I was told the readings showed constant tachycardia, but mostly in normal sinus rhythm!

The ER doctor told me I needed to follow up with my cardiologist as he didn't know what to do. I had no accompanying symptoms (breathlessness, dizziness, syncope - only the BP reading on my Apple watch, which failed to report AFIB. It said it couldn't check for AFIB while my pulse was in tachycardia).

In response to my query after returning home, my cardiologist said, yes, I could return to the gym and didn't need to come in - could wait over a month until my pre-scheduled appt with him for follow-up. A week's "event monitor" (requested by me) reported tachycardia (sinus tachycardia) and paroxysmal AFIB.

The tachycardia stopped after those three weeks, reverting to my usual rates during waking, sleeping and exercise. I kept a prior appointment at the Cleveland Clinic (after my tachycardia had stopped) - I'd wanted to discuss the Watchman Procedure with that doctor but also raised the issue of the strange tachycardia episode. That doctor wanted me to start with metoprolol (.25 mg) supposedly for the tachycardia and high blood pressure.

Only I do NOT have high blood pressure!! (He seemed to just assume it was a problem for me owing to my age, 76). I told him I had never been told I had high BP by other physicians, so seemingly reluctantly, he dropped it from my CHADD score. He still wanted me to use the metoprolol and see how it worked.

Answer - it was a complete nightmare. It dropped my pulse to 50 (without the new med, my normal had been ~ 70 BPM going about my normal business, and 50-60 at night when sleeping. No more AFIB than before the tachycardic episode (paroxysmal).

What was most terrifying was that the metoprolol made all exercise impossible. I've been exercising almost daily since I was 25 and it's of great help for my physical and mental health (my cardiologist said I was exceptionally fit for my age). As soon as I swallowed that single metoprolol, though, my pulse dropped to 50 in the day, with a blood pressure of 95/47. (Most often previously ~110-120/60). At the gym, I was on the point of passing out merely walking, while I felt dizzy and nauseated. Worst, all attempts at aerobic exercise were impossible.

I was gasping for breath, while barely managing to exercise at a fraction of my previous exertions (HIIT on treadmill and stairstepper). My pulse only went up to 80 at absolute most dropping rapidly when I stopped. Previously, it had risen to 150 - 160 at my "high intensity" point from a starting rate of baseline 70, repeated at my usual HIIT intervals of ten minutes.

I felt like I was dying - completely unable to exercise and even at a standstill, my pulse dropping to the 50s.

I have heard such great things about the Cleveland Clinic, but this medicine outcome was terrifying and if this physician insists on my taking a beta blocker, I will not return to him or this medication or anything resembling either one. Waiting to hear the results of my echocardiogram he ordered.

I had hoped to learn the origin of that period of tachycardia, but especially since it had already stopped on its own, I am frightened at his insistence on the Metoprolol. My greatest source of stress (and slightly elevated BPM and BP) is the use of that medication and the sense that the physician I saw was not paying attention to my history - especially, my past success at aerobic exercise (also weight lifting), and absence of high BP.

I guess I should attend to my son's reassurance - he was there - that "you don't HAVE to take it"!

I felt pressured and also anxious at the combination of his expertise (the Cleveland Clinic, after all!) and his inattention to my history, BP especially. I will never forget my terror at not being able to catch my breath, and complete inability to exert myself.

Waiting to get ahold of his assistant to discuss my experience, ask about the echocardiogram, and a few other issues. Meanwhile, I take some comfort from sharing this frightening experience to my peers here. Don't know where to go, but I'm holding decisions in reserve until I hear his response to the concerns I report here.