Maybe this is obvious to people, but when I had unconrolled AFib, I also slept very poorly and was always tired. Then, after going on Flecainide and it controlling the AFib, I've been sleeping soundly and waking up refreshed. Last week I had one severe AFib episode, due to having missed my morning dose of Flecainide, which started at around 5pm, and lasted through late morning the following day (it stopped about 2 hours after I had my morning Flecainide dose), and that night I barely slept at all. I now know that I can't be missing Flecainide doses, since I had that one very bad experience from missing one (although I missed other morning doses with no ill effects).
What's interesting was that the Afib started without warning (I wasn't having ectopics or anything beforehand). It started when I was doing my workout, and started while I was doing a 1-minute jump rope (and I was feeling really strong and jumping really fast when it started).
I would expect it is common to have insomnia while in AFib.
