Antithrombotic therapy and its impact on prognosis in patients with atrial fibrillation and myocardial infarction. Long-term observation results

Aim. To study antithrombotic therapy (ATT) in patients with myocardial infarction (MI) type 1 and preexisting atrial fibrillation (AF), effect of ATT on prognosis.

Material and methods. 100 patients with type 1 MI and preexisting AF were selected. The exclusion criterion was severe concomitant pathology.

Results. Only 13.0% of AF patients took anticoagulants (AC) adequately before hospitalization. 94.0% of patients in hospital and 80.5% at discharge were prescribed triple ATT at least for 1 month with transition to dual ATT (AC + disaggregant) for 12 months. ACs were prescribed in hospital in 100.0% of cases, at discharge – in 93.1%. After 1 year 8.4% of patients stopped taking ACs, after 2.3±1.9 years – 15.7%. The incidence of ischemic and hemorrhagic events didn’t differ in patients with different regimens of ATT (double/triple) and types of AСs (vitamin K antagonists/non-vitamin K antagonist ACs). In the long-term period patients, who took ACs incorrectly or stopped taking ACs, had increased risks of stroke (OR 9.580; 95% CI 1.153–79.599, p=0.0365); combined endpoint: recurrent MI + stroke + cardiovascular mortality (OR 2.556; 95% CI 1.104–5.918, p=0.0284).

Сonclusion. Patients with preexisting AF had a low adherence to ACs prior to MI. It increased after hospitalization and decreased during follow-up. In the long-term period patients, who took ACs incorrectly or stopped taking ACs, had significantly increased risks of stroke, combined endpoint. There were no differences in the prognosis depending on the type of ACs, the regimens of ATT administered in accordance with ischemic and hemorrhagic risks.