Great to see You back on here OCR. We were all concerned as You can see from comments and questions asked here and there, in the interim.
I had an attack of something similar to what happened You. It happened me two years ago at the end of four days trail riding. Gave me a bad fright alone in an Hotel room at 5 in the morning. Tests were done and nothing of significance was found. Anyway I made some changes to lifestyle not least giving up alcohol completely and increasing the exercise levels a notch. I also cut back on caffeine. The good bit is that I am still riding offroad (and on of course) and the ticker has had plenty of opportunity to protest again but it hasn't. I still get slight palpitations or occasional ectopic beats after a coffee but I'm not giving that up
Hopefully you and Your Wife will be back in action again soon.