Developments in antiplatelet therapy for acute coronary syndromes and considerations for long-term management

ABSTRACT

Objective: This article reviews the currently available antiplatelet therapies and emerging investigational drugs in the treatment of acutecoronary syndrome (ACS), and considerations for primary and secondary prevention in the long-term management of ACS patients undergoing percutaneous coronary intervention (PCI).

Research design and methods: Primary studies and reviews in the peer-reviewed, English-language literature were identified through searches of MEDLINE (1966–2008) using the terms ‘acute coronary syndrome’, ‘antiplatelet’, ‘aspirin’, ‘long-term management’, ‘P2Y₁₂ receptor’, and ‘thienopyridine’. Additional references were obtained by searching the reference lists of the identified articles. Articles were included if they were recently published and pertinent, patient-focused, and authors were recognized as leaders in the field. Current review is limited by literature search on single database.

Results: Platelets play a major role in atherogenesis and the formation of thrombi, the main events in the pathogenesis of ACS. Although aspirin is an effective antiplatelet agent, efficacy and safety data from a number of randomized clinical trials on atherothrombotic disease support the use of dual antiplatelet therapies such as aspirin and thienopyridines over single antiplatelet therapy for ACS and up to 1?year following ACS. Antiplatelet agents reduce, but do not eliminate, ischemic events after ACS due, in part, to variable individual response (or resistance) in antiplatelet agents, non-compliance, progression of atherosclerosis, modest inhibition of platelet aggregation (IPA) levels and other factors. Several antiplatelet agents, including novel P2Y₁₂-receptor antagonists and thrombin-receptor antagonists, are currently under investigation for ACS and primary and secondary prevention in the long-term management of patients undergoing PCI.

Conclusions: Current antiplatelet therapies have clinical benefits such as reducing immediate and long-term cardiovascular risk, but substantial residual risk remains indicating a need for new therapeutic agents. Additional large randomized trials are necessary to determine the most appropriate treatment regimens for ACS patients.