DC Cardioversion treatment for atrial fibrillation

Dear Ask The Doctor: What are the chances of a cardio-version being successful?

Dear Timothy: Actually the chances of immediate success in terms of restoration of sinus rhythm are good (approximately 90%). The problem is that maintenance of sinus rhythm is not very good and overall the majority of patients will revert to atrial fibrillation over the long term. The chances of successful cardioversion and maintenance of sinus rhythm are better in patients who have been in atrial fibrillation for a shorter period of time, have a structurally normal heart and no other obvious precipitating causes. It is generally worth considering the procedure on at least one occasion. It is also worth noting if you have been in atrial fibrillation for greater than 48hours, you will require anticoagulation (usually with warfarin) for a period of at least 6 weeks, including 3 weeks before a cardioversion and 3 weeks after.