My brother has A-fib; he has had cardioversions, one ablation and has taken an arrhythmic for years. He has, suprisingly to me, never been on a blood thinner except for a baby ASA. I have no clue why. I think you sound like you will be okay, especially since your score risk is so low. I am 79 and all they do is look at old people and put them on a blood thinner.