IJCS | Volume 33, Nº1, January / February 2019

73 Chart 2 - Temporal evolution of the use of anticoagulants in 318 admitted adults with atrial fibrillation at a tertiary hospital in Salvador, Bahia, Brazil. *Patients from the year 2016 were excluded from this analysis, as only data from admissions taking place in the 6 first months of that year were collected. KVA DOAC Antiplatelet agent alone No medication 14.3 28.6 35.7 29.7 20 14.9 16.7 40.6 52.7 59.7 70 18.8 18.2 14.9 5.6 10.9 9.1 10.4 100% 80% 60% 40% 20% 0% 2011 2012 2013 2014 2015 21.4 7.8 Geraldes et al. Oral anticoagulation in AF Int J Cardiovasc Sci. 2020;33(1):68-78 Original Article (2011–2016), there was a significant increase in the rate of anticoagulant use, which is largely due to the rapid incorporation of DOACs into clinical practice, which progressively replaced VKAs and antiplatelet agents. We did not find any other Brazilian study showing the evolution of anticoagulation rates in patients with AF after the introduction of DOACs on the market. A cross-sectional study involving 407 patients with AF treated at the emergence service of a tertiary center in Porto Alegre evaluated the rate of anticoagulant use. Only 34% of these patients received anticoagulation, and even in patients with CHA 2 DS 2 -VASc ≥ 2, only 40% had anticoagulants prescribed. 17 ANVISA approved the first DOAC in Brazil — dabigatran in 2011 — then two new direct inhibitors of factor Xa: rivaroxaban and apixaban. This study documented a rapid incorporation of these new anticoagulants (annual average of 10.4%), rising from28% in 2011 to 70% in 2016. This was the determining factor in the 34.8% increase in the overall use of anticoagulants in our population of patients with AF. Most contemporary international registries show the same trend. The GARFIELD AF registry (The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation), which started in 2011, with completed recruitment in follow-up phase, also showed a significant increase in the use of DOACs (4.2% to 37%) associated with to an absolute increase of 13.7% (57.4% to 71.1%) in the frequency of anticoagulant use. Likewise, the GLORIA- AF registry documented a marked increase in the overall rate of anticoagulant use (64% to 80%) between phase 1 and 2 of the study, concomitantly with the introduction and incorporation of DOACs into clinical practice, now used by 48% of patients, compared to 32% of VKA users. Both GLORIAAF and GARFIELDAF registries observed a marked decrease in the use of antiplatelet agents. 18,19 These changes in the pattern of anticoagulant use seem to be occurring in almost all regions of the world, according to GLORIA AF data, except for Asia, where more than 40% of patients with AF do not receive anticoagulants yet. Also in this registry, Latin America presented high rates of oral anticoagulants and DOACs, of 85% and 56%, respectively. It seems clear that the greatest factor for the improvement in the global anticoagulation rates in AF observed in international registries and in this study over the past 5 years was the emergence of DOACs. These drugs overcame many difficulties and limitations associated with the practical use of traditional anticoagulants, which strongly impacted the decision on its use. In addition to the DOACs, the latest therapeutic guidelines for AF may have contributed to an increase in