RESUMO
Obesity, a chronic disease established as a global epidemic by the World Health Organization, is considered a risk factor for atrial fibrillation (AF), the most common sustained cardiac arrhythmia, which has high morbidity and mortality. Although both obesity and AF are diseases associated with negative outcomes, studies have shown the presence of an obesity paradox, in which patients with a high body mass index (BMI) and AF have a better prognosis than patients with a normal BMI. Despite the fact that the mechanisms that lead to this paradox are still uncertain, adequate anticoagulation in obese patients seems to play an important role in reducing adverse events in this group. In this perspective article, the authors discuss the relationship between new oral anticoagulants (NOACs), namely, apixaban, edoxaban and rivaroxaban (factor Xa inhibitors) and dabigatran (direct inhibitor of thrombin), and the obesity paradox, seeking to deepen the understanding of the mechanism that leads to this paradox.