[Antiplatelet therapy: resistance to traditional antiaggregation drugs and role of new antiplatelet agents].

Platelet aggregation plays a key role in the development of major cardiovascular events (MACE) related to atherothrombosis. Since the appearance of coronary stenting, the importance of measuring and modulating platelet activity has considerably increased in the scientific literature during the last decade. Double antiplatelet therapy with aspirin and clopidogrel administrated to stent carriers has widely demonstrated its efficacy in the prevention of MACE compared with aspirin alone. These benefits are also present when a conservatory approach is chosen for acute coronary syndrome management. However, there are an important number of patients who develop MACE despite optimal dual antiplatelet therapy, most likely related to an incomplete platelet activity inhibition. Many studies suggest an important inter-individual variability in the response to the drugs, maybe related, at least in part, to the use of different assessment techniques of platelet aggregation. Other authors suggest an incomplete platelet inhibition as a possible explanation for the presence of MACE in patients under optimal antiplatelet therapy. Resistance to usual drugs has become a clinically relevant issue that requires an individual approach where new antiplatelet agents, such as prasugrel or ticagrelor, could play an important role as stated in current consensus documents.