Newer antiplatelet therapies in stroke prevention.

BACKGROUND

Aspirin has been the mainstay of antiplatelet therapy in stroke prevention for 30 years. In the past decade, a number of new antiplatelet strategies have been shown in clinical trials to provide some benefits over aspirin therapy. These new compounds include ticlopidine, clopidogrel and the combination of aspirin with dipyridamole.

OBJECTIVES

To review the efficacy and dosage of aspirin in stroke prevention, and to review the benefits and risks of the newer strategies, compared with aspirin. Based on the evidence from randomised, controlled clinical trials and systematic overviews, to present practical clinical guidelines for the use of aspirin and the newer antiplatelet drugs.

DISCUSSION

For most patients aspirin monotherapy is still recommended as the first line antiplatelet strategy. However, some stroke clinicians are now recommending the combination of aspirin plus dipyridamole as a first line approach. For patients who are allergic to aspirin, clopidogrel is the drug of first choice and has largely replaced ticlopidine. For aspirin failures, either combined aspirin plus dipyridamole, or clopidogrel, are recommended. The combination of aspirin plus clopidogrel has theoretical appeal, is valuable in prevention of coronary stent thrombosis and is undergoing clinical trial in stroke prevention. Other novel approaches, such as oral platelet Gp IIb/IIIa antagonists are also being evaluated.