Aim — to study the prevalence of atrial fibrillation (AF) among patients with acute coronary syndrome (ACS), to determine incidence of administration of «double» and «triple» antithrombotic therapy and its composition, to evaluate the effectiveness of INR monitoring in patients receiving warfarin at in-hospital stage. Material and methods. Prospective observational study included 402 patients who were treated in the Department of emergency cardiology of the Nizhny Novgorod Regional Clinical Hospital in 201401512017. They had persistent, paroxysmal or permanent AF and ACS with (n=68, 16.9%) and without ST-segment elevation (n=334, 83.1%). There were 227 (56.5 %) men. Mean age was 69.7±9.6 years. Results. Prevalence of AF among patients with ACS was 402 (7.98%) out of 5037 patients. AF de novo was diagnosed in 161 (40%) patients, previous AF was observed in 241 (60%). The vast majority of patients with previous AF did not receive antithrombotic treatment before admission to the hospital: antiplatelet agents before admission were administered in 38 (15.7%) out of 241 patients, anticoagulants — in 18 (7.5%) patients. In the hospital, triple antithrombotic therapy was prescribed as a rule that corresponds to current guidelines. Prevalence of triple antithrombotic therapy increased from 59.1% in 2014—2015 up to 82.6% in subsequent follow-up. Advanced prescription of anticoagulant therapy may be due to the wider introduction of new oral anticoagulants into clinical practice. Share of these drugs in anticoagulant therapy was only 19.4% earlier while this value became 47.1% in 2017. For the entire follow-up period, warfarin was administered in 216 patients and target INR was achieved in only 62 (28.7%) patients at discharge. Conclusion. Oral anticoagulants became more common in antithrombotic therapy and the proportion of NOACs has increased in the structure of anticoagulant therapy by 2017. These drugs do not require laboratory monitoring, are safer regarding the risk of hemorrhagic stroke and intracranial hemorrhage and may be an alternative to warfarin in these patients.
