Changes in Antithrombotic Therapy Prescription in Patients with a Combination of Atrial Fibrillation and Myocardial Infarction in a Specialised Inpatient Department from 2016–2019 and Associations with Prognosis

Background and Objectives: The problem of treating patients with atrial fibrillation and myocardial infarction is relevant. The issue of optimal antithrombotic therapy in these patients has not been definitively resolved. This work analyzes the influence of clinical factors and treatment on the long-term prognosis of patients. Materials and Methods: The research included 360 patients with atrial fibrillation and myocardial infarction during 2016–2019. Results: The factors associated with fatal outcomes were age (hazard ratio (HR): 1.05; 95% confidence interval (CI): 1.03–1.07; p < 0.001); stroke (HR: 1.95; 95% CI: 1.27–3.00; p = 0.0002); glomerular filtration rate (HR: 0.988; 95% CI: 0.978–0.998; p = 0.03); left ventricular ejection fraction (HR: 0.975; 95% CI: 0.957–0.999; p = 0.007); and aspirin (HR: 0.48; 95% CI: 0.31–0.73; p < 0.001). The factors associated with the combined endpoint were chronic kidney disease (HR: 1.46; 95% CI: 1.01–2.10; p = 0.04); HAS-BLED (HR: 1.23; 95% CI: 1.06–1.43; p = 0.007); percutaneous coronary intervention (HR: 0.70; 95% CI: 0.51–0.96; p = 0.03); and aspirin (HR: 0.65; 95% CI: 0.44–0.97; p = 0.03). Conclusions: Double and triple antithrombotic therapy were not associated with outcomes. Aspirin improved the prognosis for survival and the combined endpoint.