Agreed, and by all means keep taking the aspirin (I assume from the little you've told us that you are not on an anticoagulant such as Warfarin). The most serious threat we AFib sufferers are exposed to is clot formation and the possibility that will cause a stroke. Aspirin will reduce the risk, an anticoagulant will reduce the risk further.
Its simple....that question needs to be asked of your heart doctor or the pharmacist....