I was fighting a similar set of symptoms for several years, with only a little atenolol to help reduce symptoms. Several doctors just shrugged it off, one did offer to send me to a specialist but since PCP thought it trivial (he was wrong) I declined.
Wore a variety of Holter monitors over several years, even when I felt significant symptoms they didn't see anything they recognized or waved it off as PAC and PVC. Even one monitor's "AI Software!" said NOTHING. I tried to call the company and ask them WTF, but got nowhere. It may not be much but you cannot just wave off all PAC and PVC!
I'm always watching and fiddling with my diet, I made a couple of small changes really hoping to address blood sugar, and possibly blood pressure, but that's when the arrhythmia suddenly reduced by about 90%. If you want to play a long shot, do a consult with a nutritionist and see what happens!