Background: The aim of this study was to investigate the frequency of oral anticoagulant drugs and time in therapeutic range in patients receiving warfarin in addition to the epi-demiological trial of non-valvular atrial fibrillation previously conducted in Turkey (The Atrial Fibrillation: Epidemiological Registry trial). Furthermore, the prevalence of major adverse events and mortality rates of the patients were evaluated during the long-term follow-up period.

Methods: We created a national data registry for non-valvular atrial fibrillation patients, reflecting all geographic regions by population density. In that context, the study included all consecutive atrial fibrillation patients older than 18 years of age who were admitted to the cardiology outpatient clinic except for patients those with prosthetic heart valvesand rheumatic mitral valve stenosis.

Results: This study included 2592 patients from 35 different centers. The mean age was 68.7 ± 11.1 years, and 55.5% of the patients were female. The most common comorbid diseases were chronic kidney disease (69%) and hypertension (65.5%). The time in ther- apeutic range rate in the general population was 40%, and the mortality rate at 5-year follow-up was 29.4%.

Conclusion: The Atrial Fibrillation: Epidemiological Registry 2 study showed higher use of anticoagulant in non-valvular atrial fibrillation patients than in previous national stud-ies. Furthermore, this study demonstrated that most of the non-valvular atrial fibrilla- tion patients are in the high-risk group and the time in therapeutic range rates are still low in Turkey. As a result, this is a significant reason for switching from warfarin to non-K vitamin-dependent new oral anticoagulant treatments.