SAFETY OF DIRECT ORAL ANTICOAGULANTS IN PATIENTS WITH ATRIAL FIBRILLATION: A TWO-YEAR COHORT STUDY

Real-life clinical application of anticoagulant drugs is currently one of the most promising trends in cardiology. With relation to initial prescription of anticoagulants, the updated 2016  guidelines  on the management  of patients with atrial fibrillation (AF) highlight direct oral anticoagulants (DOAC) rather than vitamin K antagonists, but, unfortunately, they are not clear about whether different DOAC have the same clinical effect of there is a significant difference.

Material and methods. We conducted a comparative analysis of the safety of DOAC in patients with non-valvular AF and attempted to identify the potential predictors of hemorrhagic events in order to assess  the predictive value of bleeding risk scores. For this purpose, we observed 117 patients with non-valvular AF who received DOAC to prevent TEC for 2 years (24 months).

Results. Over the entire period of follow-up, no major bleeding or thromboembolic complications were recorded, supporting the good efficacy and safety profile of DOAC. We analysed the prognostic value of various scores and found that HAS-BLED had the highest predictive value in the group of patients treated with the direct thrombin inhibitor (dabigatran). Treatment with factor Xa inhibitors (rivaroxaban and apixaban) did not demonstrate a similar trend.

Conclusion. Over the 2-year follow-up of 117 patients treated with DOAC, we were able to show that this group of drugs in patients with non-valvular AF is effective and safe given that adequate doses in accordance with the instructions are administered; this is true for both direct thrombin inhibitors (dabigatran) and factor Xa inhibitors (rivaroxaban and apixaban). HAS-BLED was prognostically more accurate when the direct thrombin inhibitor dabigatran was administered.

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