Statistically, with variance due to skill of the electrophysiologist in question AND in the complexity/stage of progression of the patient, the average success rate for first (called 'index') ablations if about 75-80%. Second attempts do a bit better, about 80-85%. The very best EPs have better results because they can subdue the complexity of the more advanced and complex cases (as our hearts age, and as our atrial fibrillation/flutter goes on, it becomes more difficult to treat because more areas in them generate the rogue cells that compete with the sino-atrial node (SA node).
It took two tries, seven months apart, to find the tiny gap in the lesion 'dam' that the EP made the first time. As he was zapping my third pulmonary vein, my heart lurched into reliable normal sinus, and they knew they had found that tiny gap they'd missed. But remember, 75-80% of all index ablations are successful. I am now 29 months free of AF.
I am unsure of why you must be on Dofetilide if your ablation succeeds. Perhaps you have known complexity, advanced stage of arrhythmia....it is beyond me. In the heavy majority of cases, the patient might be on propafenone or Flecainide for a few weeks to help the heart calm and heal, and then they go off it for two or more weeks before the confirmatory Holter monitor assessment, which takes place near 10-12 weeks post op. Some need the extra 'insurance', some just need metoprolol for a few weeks and nothing more. It depends on the EP and the patient.
I don't know if you know it already, but Tikosyn requires (normally) at least two-three days of administration in hospital on startup because it can have serious side effects. Whatever you are told to expect and to do, though, THAT is your prescription, and please follow it to the letter.
I am no longer a competitive or recreational runner. I was doing some of that before my first ablation, but not since. I do walk aggressively, sometimes jogging, and I often climb two flights of steep steps on an oceanside bluff, each flight approx 160 steps. I am 73, and by the time I'm halfway up the first flight I am at 140 BPM. So, theoretically maxed out. And this goes on for the next six minutes or more with no hiccups. Hopefully, some weeks/months after your (successful) ablation you can look forward to a similar effort, relatively. Note that it really depends on your risk factors and on why you developed the arrhythmia in the first place. If, as some find, it was due to intense exercise, maybe also too long, then.....................