ABSTRACT
Platelet activation is a pivotal event in the pathophysiology of acute coronary syndromes
(ACS) and percutaneous coronary intervention (PCI) and has a substantial impact on
the outcomes in these settings. Aggressive implementation of antiplatelet therapy
has significantly decreased adverse cardiovascular events, such as death, myocardial
infarction (MI), stroke, and repeat revascularization. Although the widespread use
of aspirin has contributed to this improvement, many patients continue to have a significant
risk of recurrent events during the ensuing months to years. The advent of other antiplatelet
agents, notably the thienopyridine clopidogrel bisulfate has heralded a new era of
combined antiplatelet blockade, offering the hope of better outcomes. Recently, clinical
trials have tested the use of dual oral antiplatelet blockade and have shown impressive
results. Notably, the Clopidogrel in Unstable Angina to Prevent Recurrent Events (CURE)
trial found that dual therapy with clopidogrel and aspirin in ACS reduced adverse
cardiovascular events by 20% at 1 year (p < 0.001). The PCI-CURE substudy of CURE and the Clopidogrel for the Reduction of
Events During Observation (CREDO) trial demonstrated that these benefits extend to
patients undergoing both urgent and elective PCI. This article will explore the current
role of and controversies in oral antiplatelet therapy after ACS and PCI.
KEYWORDS
Aspirin - clopidogrel - acute coronary syndromes - percutaneous coronary intervention
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Dr.
D. Bhatt
Cleveland Clinic Foundation, Department of Cardiovascular Medicine/F25
9500 Euclid Avenue, Cleveland, Ohio 44195
Email: bhattd@ccf.org