New antiplatelet agents in the treatment of acute coronary syndromes.

Effective antagonism of the P2Y12 platelet receptor is central to the treatment of acute coronary syndrome (ACS) patients, especially in the setting of percutaneous coronary intervention and stenting. According to consensus guidelines, early revascularization and intensive antiplatelet therapy are key to reducing the complications that arise from myocardial ischaemia and the recurrence of cardiovascular events. Until recently, clopidogrel was the key P2Y12 antagonist advocated, but due to several limitations as an antiplatelet agent, newer drugs with more predictable, rapid and potent effects have been developed. Prasugrel and ticagrelor are now the recommended first-line agents in patients presenting with non-ST-segment elevation ACS and ST-segment elevation ACS, due to large-scale randomized trials that demonstrated net clinical benefit of these agents over clopidogrel, as stated in the European guidelines. Although no study has directly compared the two agents, analysis of the data to date suggests that certain patient types, such as diabetics, those with ST-segment elevation myocardial infarction or renal failure and the elderly may have a better outcome with one agent over the other. Further studies are needed to confirm these differences and answer pending questions regarding the use of these drugs to optimize efficacy while minimizing adverse events, such as bleeding. The aim of this review is to provide an overview of the current P2Y12 receptor antagonists in the treatment of ACS, with a focus on issues of appropriate agent selection, timing of treatment, bleeding risk and the future role of personalized treatment using platelet function and genetic testing.