The FIRST registry: Comparison of anticoagulant treatment in patients with atrial fibrillation

Aim: The FIRST registry aimed to compare patients with atrial fibrillation treated with dabigatran or warfarin. Methods: The study was performed in 10 centres in the Czech Republic. Results: Upon enrolment, 33.2% and 35.6% of patients respectively showed sinus rhythm. The last dose of warfarin before changing to dabigatran was higher than the maintenance dose 6.4 ± 4.3 mg vs. 4.6 ± 3.2 mg (p < 0.001). The patients did not differ in the CHA2DS2-VASc score. The principal difference was in the HAS BLED score: 55.3% of patients treated with dabigatran demonstrated a score of three or more while only 33.5% of those treated with warfarin did (p < 0.001). In 14.7% of patients treated with dabigatran, serious bleeding was observed during the previous treatment with warfarin. In patients treated with warfarin serious bleeding occurred in 2.0%. The most frequent reason (56.6%) for changing over to dabigatran was the impossibility to maintain INR within the therapeutic range. Conclusion: Patients are transferred from warfarin to dabigatran in particular due to the impossibility to maintain INR within the therapeutic range, and these are more frequently patients with a higher bleeding risk.