You think you’re healthy, eat well, take good care of yourself (well, maybe you could get more exercise). Life is good. You don’t feel like you’re under stress. But every now and then your heart does flip-flops. You can feel it pounding, you can feel it throbbing in your neck. Then, in the middle of the night, it’s racing. You feel anxious. You check your pulse—140 beats per minute, maybe more. You go to the emergency room. It’s 190 beats per minute now. They tell you, “You have atrial fibrillation.” Atrial fibwhat? They hook you up to an IV, give you some drugs and soon, gradually, you begin to feel almost normal again. But now your mind starts racing: What is atrial fibrillation? What causes atrial fibrillation? Is there a cure for atrial fibrillation? What drugs were in that drip (and what are the side effects)? Just how serious is atrial fibrillation?