Prevalence of patients with myocardial infarction (MI) and atrial fibrillation (AF) has been growing every year. These patients represent a highest risk group and, thus, require special attention of clinicians. The article foсused on mechanisms of the AF and MI interaction, special aspects of prediction depending on the type of AF and MI, and the issue of antithrombotic therapy in this patient category. A group of AF-associated, embologenic MIs was isolated, and diagnostic criteria and therapeutic regimens were provided.