Prospective randomized (rhythm control or rate control) Objective of study 1. To analyze long term outcome of patients with acute stroke with atrial fibrillation according to the rhythm control 2. To analyze recurrence rate of atrial fibrillation or recurrence stroke in patients with acute stroke according to the rhythm control (by antiarrhythmic drug, cardioversion, catheter ablation)
Inclusion Criteria: 1. Patients with Atrial fibrillation (20\~80 years old) 2. patients with Acute stroke within 7 days 3. LA diameter \< 55mm 4. patients possible to anticoagulation and anti arrhythmic drug 5. NIHSS score ≤12 Exclusion Criteria: 1. Hemorrhagic transformation 2. Large cerebral lesion or cerebellar lesion (more than 1/3 of MCA area and 1/2 of ACA area, 1/2 of PCA area, 1/2 of cerebellar area) 3. active internal bleeding 4. Impossible to anticoagulation or anti arrhythmic drug 5. Valvular AF (MA\> GII, Mechanical valve, Mitral valve replacement) 6. LV ejection fraction \< 30% 7. Structural cardiac disease 8. Catheter ablation history for AF, Cardiac surgery 9. Already prescribed anti arrhythmic drugs 10. With severe medical disease 11. Expected survival \< 1year 12. Severe alcoholics, drug addiction 14\. Contraindication to MRI 15. Pregnancy