I've had SVT (supraventricular tachycardia) since a few years before my AVR. I had hoped that my AVR would solve this issue - but it didn't
I still get them. I don't know what, if anything, triggers them. A 24 hour holter monitor showed that I have a few SVTs during the day - sometimes just a few beats. My cardiologist suggested increasing my beta blocker dosage (bisoprolol) on days when this happens.
My SVTs have been scary for a while, but now, I kind of just let them happen. They usually resolve within five minutes or so. If they last longer, I get concerned, but am almost sure that they'll stop and I can get on with my life. (FWIW - when I was in the hospital with a Baker's Cyst in my leg, I had a wireless heart monitor attached. I got an SVT while I was talking to my wife - no big deal - and a nurse came rushing into my room, asking who I was talking to. I asked her why that should matter - and she told me that my heart was racing. I told her that it was no big deal. I get those things. I wasn't upset. This, apparently, was the first time she saw a tachycardia without a real reason.
So - you may have to put up with your tachycardia (if it's like mine). It'll probably last only a few minutes and will stop as suddenly as it started. You'll get used to it -- you may not like it - but you'll get used to riding it out. Beta blockers may help.