> an episode of afib brought-on by triggering my vagus nerve
I get ectopic beats when I've got trapped gas in the stomach. Sounds weird, but generally when I get them I realize I need to stand up (because I've usually been sitting with bad posture which leads to the trapped gas) and have a large belch and then it calms down. I mentioned this to my doc and he said it was Roemheld syndrome ( https://en.wikipedia.org/wiki/Roemheld_syndrome ) which is vagus nerve-related.
Yeah I got quite scared when it happened for the first time.