I was diagnosed with an overactive thyroid some 3 years ago. Had radio active iodine treatment. Still taking NeoMercazole now. Now they've diagnosed me with Atrial Fibrillation. Symptoms have always been no energy, washed out, fainting spells, breathlessness, raspy cough, thirsty, some nausea in mornings, racing heart. Had 2 mini strokes 18 months ago. Symptoms getting slowly worse except not fainting any more. Just feel really lousy every day. On Avapro, Natrilix, Caduet, Warfarin, Metroprolol, Neo-Mercazole. I feel like a pill bottle. Doctors just can't fix me. I've read that a thyroid can bring on Atrial Fibrillation or vice versa, does anyone know anything about this? I don't know if its the heart or the thyroid or maybe something else. Nothing seems to make me feel any better at all and I've been like it for the past 4 years.