Heterogeneity of efficacy and safety of antiplatelet therapy in cardiovascular and cerebrovascular disease.

The beneficial effects of antiplatelet therapy for secondary prevention in patients with prior cardiovascular or cerebrovascular events, including stroke, transient ischemic attack, and myocardial infarction, have been demonstrated repeatedly over the past decade. It is increasingly apparent that pathophysiologic differences between patients with different types of prior vascular events have an important effect on treatment outcomes. Several large, important trials of antiplatelet therapies, including MATCH, CHARISMA, ESPRIT, and TRITON-TIMI 38, underscore the heterogeneity of the efficacy and safety of antiplatelet agents in patients with recent cerebrovascular disease, compared with patients with recent acute coronary syndromes. Trial data therefore support an individualized approach to antithrombotic therapy for secondary vascular-event prevention that is appropriate for any probable future vascular events and actively reduces the impact of modifiable risk factors common to all vascular events. The potential for benefit in reducing recurrent vascular events must be weighed against the increased risk of bleeding and of patient non-responsiveness to treatment. A number of other factors also need to be considered, including drug interactions, patient compliance, and adverse-effect profiles. Overall, there is now a substantial body of clinical trial evidence that supports the need to carefully individualize antiplatelet therapy and other risk-reducing strategies on the basis of each patient's pathology and specific needs.