Get yourself checked out by a dr., and if there's no underlying dangerous medical condition, then the chance of cardiac arrest from PVCs is somewhere between slim and none. I usually get at least a couple a day and have for as long as I can remember, but I have a CHD too. The worst that has happened to me as a result of PVCs is I had a whole bunch of them in a row with no normal beats in between for like two or three minutes and I passed out, but apparently when I did that interrupted whatever biophysical cycle was causing them because I was fine within a few minutes (I did get checked out by a dr. ASAP just to be on the safe side after that incident of course).
"Now faith is the substance of things hoped for, the evidence of things unseen." ~ Hebrews 11:1 ~