Monitoring antiplatelet therapy: where are we now?

Single antiplatelet therapy represents the cornerstone of thrombosis prevention in atherosclerotic cardiovascular disease. Dual antiplatelet therapy (DAPT), consisting of aspirin plus a P2Y₁₂inhibitor, is the standard of care for patients with acute coronary syndrome or undergoing both coronary and peripheral percutaneous interventions. Recent data suggest the efficacy of DAPT also after minor stroke. In this setting, a large body of evidence has documented that genetic and acquired patients' characteristics may affect the magnitude of platelet inhibition induced by antiplatelet agents. The implementation of tools allowing the identification and prediction of platelet inhibition has recently been shown to improve outcomes, leading to an optimal balance between antithrombotic efficacy and bleeding risk. We are therefore clearly moving towards tailored antiplatelet therapy.The aim of this paper is to summarize the available evidence on the evaluation of platelet inhibition in patients with coronary, peripheral, or cerebrovascular atherosclerosis. We will here focus on antiplatelet therapy based on both aspirin and P2Y₁₂inhibitors. In addition, we provide practical insights into the clinical settings in which it appears reasonable to implement antiplatelet therapy monitoring.