For the past few weeks, Ive been waking up with an extremely elevated heart rate (200 bpm or so). It terrifies me and I've been to the ER 3x for it during this period. EKG comes back normal and clean each time, but its not being take during the episode. Episodes last as long as 10-15 minutes. I'm terrified to go to sleep at this point, because I fear that I may wake up with symptoms. ER docs tell me its anxiety, which is fine since I do get panic attacks, but I want more information.