Antithrombotic therapy in patients with coronary heart disease and atrial fibrillation after direct myocardial revascularization

Aim. To evaluate the clinical efficacy and safety of direct oral anticoagulants versus warfarin as part of antithrombotic therapy (ATT), namely, to study the frequency of bleeding and thromboembolic complications in patients with atrial fibrillation (AF) after direct myocardial revascularization in combination with radiofrequency isolation of pulmonary veins. Material and Methods. A total of 44 patients (36 men) aged 44–77 years (average age of 63.5 ± 7.8 years) with coronary heart disease, indications for direct myocardial revascularization, and AF were included in the study from 2014 to 2016. The observation period was 24 months. Results. Warfarin was one of the components of ATT in 20 patients (48%). However, the target values of international normalized ratio (INR) within the therapeutic range for over 70% of the time were achieved only in seven patients. Two patients who were taking warfarin without achieving target INR values for 24 months suffered from ischemic stroke. One patient taking warfarin (without regular INR control) had gastrointestinal bleeding requiring hospitalization and conservative therapy; ten patients had minor bleedings (nasal and gingival bleeding). All patients, who suffered from thromboembolic and hemorrhagic complications and had inadequate warfarin intake, were recommended to switch to direct oral anticoagulants (DOAC). Thirteen patients (29%) were administered with DOAC: five patients took rivaroxaban 20 mg/day, four patients took dabigatran 300 mg/day, and four patients took apixaban 10 mg/day. DOAC therapy was administered in combination with one of the antiplatelet drugs (aspirin or clopidogrel). In the case of DOAC administration, only minor bleedings were observed: one patient had hemorrhoidal bleeding and four patients had nasal bleedings, which did not require hospitalization, medical intervention, or suspension of anticoagulant therapy. There were no other adverse events in patients taking DOAC. Conclusions. Patients administered with DOAC as a part of antithrombotic therapy after coronary bypass surgery and surgical epicardial radiofrequency isolation of the pulmonary veins had lower incidence rates of thromboembolic and hemorrhagic complications compared with the rates in patients taking warfarin. However, no statistically significant differences were found between the groups due to the small sample size.