I suffer from periodic palpitations too, which seem to recur episodically every 5-6 months or so. I can trigger them by drinking 4-5 beers, so I effectively gave up alcohol a couple of years ago. The first time I noticed them was quite a few years ago, a few days after doing a MTB ultra-endurance event. The doctor said exacerbating factors were a) coffee, b) alcohol, and c) strenuous endurance exercise. He asked if I habitually indulged in any of those three. At the time my life consisted of waking up at 6am, shotgunning a double espresso, doing a one hour tempo effort to work, chugging coffee all day long, then doing a one hour tempo effort back to daycare, then home, then a 7% IPA the second I got in the door on the way to the shower… lol
Anyway, I still drink way too much coffee and probably ride harder (though less volume) and mostly the palpitations are under control…