Unknown Heart Condition

@fuzzlepuff have you had a patch monitor for a week or a month to see what is going on? You could also get a smart watch or Kardia device (though it sounds like something continuous would be best).

A positive ANA does not always mean an autoimmune disorder, I have been told. Do you see a rheumatologist? Some autoimmune issues can involve the heart though I don't know much about it.

Sorry you are going through this and someone else will chime in!

Hi! Yes I’ve worn a Holter monitor for about a month. Didn’t show anything but tachycardia

That's good @fuzziepuff. No arrythmias. I am glad the beta blocker is helping. I hope your heart calms down on it!

You may have a gene that makes you metabolize metoprolol poorly, so too much of it gets built up in your system and your heart begins to slow too much. This might account for your darkened vision, but a blood pressure cuff with heart rate three, four times a day should help to show if this is what's happening.

Just how is it that you ended up here? Have you had any tests that reveal you have a heart problem? Chest pain does not mean a heart problem. It could be autonomic system issues among other issues. Metaprolol is a blood pressure med and it also can be used in certain heart conditions. You say your heart doctor sent you to this site to get information on your condition?

The mechanism of metoprolol is a cardioselective, beta-1 adrenergic receptor blocker which has the desired effects of reducing heart rate and blood pressure and increasing cardiac output. The metabolism of metoprolol occurs primarily via the CYP2D6 enzyme, with reported estimates of approximately 70–80%. See https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10058912/
Genetic testing of the Cytochrome P450 (CYP) would tell you what kind of metabolizer of CYP2D6 you are. Example I am an "intermediate metabolizer" of 2D6.
Is it possible that this might be an endocrine system problem?

The medication helps with my blackness in my vision along with chest pain, but it’s been getting worse again. I ended up here because my doctor has no clue what’s wrong. All my tests are coming back normal.

Also my heart rate would be high. 135-150. It has come down a bit now.

I just want to note to everyone that I get these spells usually when I stop breathing.

So @fuzziepuff is the basic question why you stop breathing? Do you need a pulmonologist? Does your heart rate speed up before you can't breathe, or does the heart speed up afterwards?

It's when I yawn, stretch, move around, any time I tend to just step breathing for a moment. Then after that, I get this spell where I see blackness pulsing in my vision, chest pain, a headache, and sometimes lightheadedness and I feel like I'll pass out. The chest pain feels like I am on a roller-coaster.