Hi. Since my last cardioversion 2 weeks ago I am in sinus rhythm but am aware of every heart beat and feel short of breath. My last fast AF was brought on by swimming which has never happened before I had been swimming 2 miles a week with no ill effects prior to this episode. Is this the nature of AF does it progress to excercise intolerant. I am on bisoprolol 7.5mgs. I have paroxysmal AF. I have an ablation booked for December and am wondering wether it is likely to help with my excercise intolerance. Do other people with AF experience the feeling of fight or flight that seems ever present ie constantly on edge and nervous.