All who suffer from heart disease have a statistically higher risk of a heart failure than does the general population who do not have heart problems. This is true too as we go into higher age groups, the older one is the more likely they will experience a physical failure of some type or another.
I suffer from AFib myself and know I am at higher risk for additional heart problems, and for stroke even though I take an anticoagulant (Warfarin).
I don't know how much higher, but I believe I will see tomorrow and the many days after, I can't waste the time I have worrying about the possibilities.
That said, if you are having more "symptoms", not sure what you mean, you may benefit from discussing the specifics of the symptoms with your doctor.