Hi I've just had my first incident of atrial flutter with fast ventricular response, (I think this would be called "lone AF" as I'm healthy 56 year old otherwise), and cardioverted back to normal rhythm in A and E by iv flecanide 10 days ago. I now have a 100mg flecanide tablet of it to take in case it kicks off again, but am also on daily bisoprolol, 5mg, then 2.5mg for last 2 days. My issue is sleep, or rather, lack of it, due to a breathing problem when I'm falling asleep. I just breathe normally, out and in, but then breathe out and don't breathe in, just as I'm drifting off, then come round in a panic short of air. 2 nights out of last 4 I've had NO sleep to speak of, the other 2 nights, i did drift off eventually and then got a good 5 hours. My doc has said don't worry hopefully sleep will settle down, but its been on the verge of this since the cardioversion. I'm just worried if it gets worse, I'll be in real bother. Also, I feel ok walking or riding a bike, but coming back to rest I then get breathless. Its like the bisoprolol is messing up my breathing when at rest. Has anyone else had this, with or without bisoprolol?