Current Evidence for the Use of Aspirin in Patients with Atrial Fibrillation and a CHA2DS2-Vasc=1

Aspirin was once the mainstay of stroke prevention in patients with atrial fibrillation. Its popularity was based on the results of the SPAF and PATAF trials, which showed the low risks of this therapy and the many benefits it had to offer in terms of embolic complications prevention. Nevertheless, aspirin has lost popularity in atrial fibrillation since the CHADS, CHA2DS2-VASc and HASBLED scoring systems were first introduced. These scoring systems showed a different perspective, which highlighted that thromboembolic risk varied among individuals and that a generalization on antiplatelet therapy for atrial fibrillation was not effective. These caveats gave support to additional treatments based on anticoagulation, including warfarin and direct oral anticoagulants. These treatments gained popularity based on the superiority over warfarin, first described on the BAFTA trial, which nominated the warfarin as the standard of care for atrial fibrillation thromboembolic prevention. Since then, direct anticoagulation therapies have gained popularity based on the results of the ARISTOTLE (apixaban), RE-LY (dabigatran), ROCKET-AF (rivaroxaban), ENGAGE TIMI 48 AF (edoxaban) trials. However, the CHA2DS2-VASc score was generous with aspirin, since it opened a possible recommendation for low CHA2DS2-VASc scores (0-1). This comprehensive literature review is intended to discuss the arguments behind this last statement and to show the available evidence in favor of and against aspirin for non-valvular atrial fibrillation in low thromboembolic risk patients.