From January 2023 to December 2025, 300 elderly patients with nonvalvular atrial fibrillation in Drum Tower Hospital Affiliated to Medical Scholl of Nanjing University will be enrolled to compare the efficacy and safety of rivaroxaban-H, rivaroxaban-M and rivaroxaban-L dose in elderly patients after 24-month follow-up.

To explore the appropriate dose of rivaroxaban to prevent stroke in elderly Chinese patients with nonvalvular atrial fibrillation in order to improve the effectiveness and safety of anticoagulation therapy. From January 2023 to December 2025, 300 elderly patients with nonvalvular atrial fibrillation in Drum Tower Hospital Affiliated to Medical Scholl of Nanjing University will be enrolled to compare the efficacy and safety of rivaroxaban-H, rivaroxaban-M and rivaroxaban-L dose in elderly patients after 24-month follow-up. The efficacy indexes include stroke, non-CNS systemic embolism, fatal stroke, transient ischemic attack and myocardial infarction, and the safety indexes include major bleeding, non-major clinically relevant bleeding, minor bleeding events.

Inclusion Criteria:

• Age≥75 years
• Chinese patient: male or female
• Patients had to be diagnosed as nonvalvular atrial fibrillation (NVAF)

Exclusion Criteria:

• Patients with anemia (hemoglobin<100g/L), known human immunodeficiency virus infection, female patients who were pregnant or lactating and patients for whom warfarin was contraindicated, were also excluded
• Patients with calculated creatine clearance vulue<30ml/min
• Patients expected to chronically use a non-steroidal anti-inflammatory agent (except for external preparations) and those treated with a strong cytochrome P4503A4 inhibitor (eg, ketoconazole, clarithromycin, or protease inhibitors) or a strong cytochrome P450 3A4 inducer (eg, rifampicin) during the trial

Chinese patients aged ≥75 years with nonvalvular atrial fibrillation