This study is prospective Cohort study which was performed in multicenter (General Hospital) in Korea. Inclusion criteria is all patients with atrial fibrillation who visit hospital. The purpose is to analyze complication, composite outcome (all cause mortality, hospitalization, the incidence of stroke, heart failure and cardiovascular event (MACE)) according to the 1) the use of anti-arrhythmic drugs (AADs), 2) use of medication for rate control (beta blocker, calcium channel blocker and digoxin) and 3) use of anticoagulation agents (warfarin, coumadin, an NOAC)