Inclusion Criteria- Male or female subjects 18 to 80 years of age
- Non-valvular AF supported by abnormal ECG documented for two times (interval of more than 1 week) within 6 months prior to randomization.
- CHADS2 Score of at least 1.
Exclusion Criteria- Subjects with mitral valve disease
- Subjects with previous valvular heart surgery
- Contraindication for anticoagulants
- Conditions associated with high risk of bleeding
- Acute coronary syndromes (ACS), percutaneous coronary intervention (PCI), MI, stroke, transient ischemic attack (TIA) or coronary artery/cardiac/other major surgery within the previous 30 days
- Active infective endocarditis or life-expectancy < 12 months