I recently went back into atrial fib after almost two years of sinus rhythm following a successful cardioversion. During this time I was taking a Cardizem but no anti-arrythmic. I went to a new cardio doc and he put me on Flecainide and told me we could do another cardioversion as soon as my INR was theraputic, and that if I was lucky the Flecainide might put me back into NSR. Sure enough, when I went to get the cardioversion done, I was in NSR. This was after about a week on the Flecaindide, 100mg BID. That's the good news. The bad news is, this drug is causing me noticable shortness of breath. I have less exercise capacity than I did when I was in a-fib and I'm not liking ot. It has other effects too, such as fatigue and wild dreams, plus some spaciness and vision weirdness. I can deal with that but the shortness of breath is really bugging me. I am unclear whether this is side effect incidental to the drug or if it is due to the negative inotropic effect. My question is, has anybody out there experience the same and did it go aways as you got used to it? Or, did an adjustment of dose help? I think when I see my cardio again in a week he is going to tell me I need to stay on it to maintain NSR. If it doesn't get better, I don't think I can do that. Any comment, anybody?