I had an afib attack a few years back & was diagnosed w/WPW. Had catheter ablation...afib returned 1 year later. I am now on flecanide for rhythm & toprol 25 for heart rate/bp for the last 9 months. Over the last 3 months, I've been getting attacks of a swollen throat that are getting more severe every week (cardiologist, pulmonologist, e.n.t., gastroenterologist, er docs all have no clue!). I feel that it is probably angioneurotic edema that has been brought on by the beta blocker (has been linked to ace inhibitors as well). I'll post back in a few weeks after being off of Toprol (cardiologist approved). BTW...I am only 36.