You may want to look up the subject on the MedHelp
http://www.medhelp.org/medical-information/show/804/Atrial-fibrillation-flutter
The first considerations with AFIb is the prevention of clots, a simple aspirin a day (with a meal is best) is a big help here, and controlling HR, keep it from going too high. Here a beta blocker is usually used (a prescription drug).
If the symptoms are severe, they are not for many people, more aggressive drugs and invasive procedures may be the best path to a solution.
As I hope the link I provided explained, AFib is an electrical/timing/transmission problem in the heart and while many are able to convert to normal sinus rhythm (NSR) with drugs and/or electrocardioversion, some do not respond to those treatments.
As with most health problems, if it is caught early and you are not advanced years of age, say 70 and over, the chances for a recovery of NSR will more likely be successful. Otherwise, many just live with the symptoms addressing the clot mitigation and rate control mentioned above.