What I can tell you is I made some adjustments in the supplements. It was not spontaneous. I noticed in late Feb I was starting to feel better when resting at night. And then by mid March is started to feel better with fewer event during the day. And recently I am having more "normal sinus rhythm" events according to the Kardia device that I bought per my EP. I have not taken any prescription meds for the PACs/PVCs/Afib except for eliquis for clotting issues. I still have a few or occasional PVCs and PACs. That has been replaced by a lot more normal sinus mixed in with what Karida calls "Unclassified". That means Afib is not detected but it is not quite fall under "normal". I suspect it is occasional PVCs. I am not paying for the higher version of Kardia which includes PVCs and other things. I let my EP read what is on my smart phone vs paying Kardia $11/month. But I cannot say for sure the change in supplements is what helped. I was taking 400 mg of Ubiquinol and upped it to 700 mg a day. Note I am taking Ubiquinol and not Ubiquinone. They are very different versions of Coq10. Ubiquinol is highly bioavailable whereas ubiquinone is not very bioavailable.
I added taurine, starting at 500 mg/ day and then doubled it to 1000/day.
I was taking magnesium taurate @ 125mg/day and doubled that to 250mg/day.
I also started L-arginine 700mg/day and doubled it to 1400mg/day.
I also was taking D-ribose 5 grams/day when this started and continued taking it.
I have been on a strict diet for years that I started for a problem with GI problems and fatigue but is heart healthy. The important part of the diet is that it is an anti-inflammatory diet. Much like the Mediterranean diet.
One last little note : our dog had a heart murmur appear at age 7 years. We put her on high doses of ubiquinol (200 mg for a 40# dog) as well as diet changes. 2 months later she still had a murmur but then 8 months later the murmur was gone.

I was bradycardic. Heart rates in the 30’s and 40,s at rest. Doctors were not concerned because my HR increased when I got active. I developed a fib. That’s when the tachycardia became an issue and was put on Multaq. It wasn’t working. I was cardioverted 4 x in 6 months. I had an ablation. This seems to have curtailed the a fib( fingers crossed). I am on metoprolol to keep my heart rate down. This in turn lowered my HR to the point where I had to have a pacemaker implanted to keep it elevated. After the ablation I wore a monitor which showed my heart paused 1200 times in 10 days. The longest duration was 8 seconds.