Yes on the afib and anti-coagulation, apparently I go in and out of afib more than I thought. They did an EKG and chest X-ray when I was admitted. The EKG had the long spacing with little bouncy waveform between beats, and then about five extremely rapid beats in a row. I feel it, but when it changes in and out so fast it's hard to identify. My wife got me a KardiaMobile. Pretty neat you can do EKGs and read them via Bluetooth on your phone or iPad - it really does work; now I just have to learn how to read the EKG. I never knew about the left atrial appendage - a perfect little pocket for forming blood clots. The chest X-ray right after the TAVR - hadn't even moved out of the OR was night and day from the one done just before the TAVR - pretty amazing what happens when the valves are doing the right things.
I do know what you mean about the N95 masks. I'd been having problems breathing with one during the past year, but the recently that's all changed, but I also don't wear one all day. My wife's case of covid brain seems to be a couple of things - sometimes she's a little foggy and other times she's just so irritable about it all that she doesn't think rationally, and sometimes she's pretty normal. She has balance problems ( and falls) on and off even more than a year after covid. There's also some lingering taste and smell issues which are very irritating to her because she can't enjoy what she has always liked. It's just not a disease to be taken lightly.
