Hi Mike,
Came across an older post of yours asking about afib of a fleeting nature or a few seconds duration. I know you have GERD afib so this may be of use to you.
I used to have these mini afibs during the day, normally after meals. I would immediately take a double strength "Mylanta" antacid tablet and that would terminate them and stop them from turning into a full blown afib attack. When I had a 24 hour pH study a few years back I had one of these mini afibs while hooked up to the pH monitor and the mini afib occured at the same time as the pH monitor in my esophagus recorded an extremely high acid reading so I think they are definately GERD related.
Have a great Christmas and Happy New Year.
Dean in Sydney.