The rsik of stroke is higher when in Afib than when not. However, for true statistics, i recommend you look on the american heart association website under their entry for a-fib. Being on blood thinner is the right course of action. Talk to a professional about the true risk differential. Best wishes.
My understanding is that if your PT INR is above 2 then your a-fib is unlikely to generate a clot. The whole idea is to keep your PT INR score in the "theraputic" range of from 2 - 3. BTW, what anticoagulant are you taking? Coumadin (warfarin) is effective but you have to monitor your PT INR pretty closely. No one I know has been on other anticoagulants so I have no experience with them.
(3 months paced and going strong)