Swedish researchers have found that a new clot-busting drug called Pradaxa may be more safe and more effective than the commonly used drug warfarin at preventing clots and strokes in people who suffer from atrial fibrillation. Warfarin use must be carefully monitored because there is a very small range at which the drug both prevents clots and yet does not cause bleeding. But in a new study, Pradaxa was shown to be both more effective than warfarin and have less of a chance of causing bleeding....