Individualized antiplatelet therapy after drug-eluting stent deployment: Implication of clinical trials of different durations of dual antiplatelet therapy.

At present, there is consensus that prolonged dual antiplatelet therapy (DAPT) is effective to reduce cardiovascular events at the expense of bleeding complication events. A causal relationship of prolonged DAPT with an increase in mortality remains debatable, however, it appears to be obvious that bleeding complications are associated with an increase in cardiac events. Thus, individualized optimal DAPT duration balancing the risk and benefit of DAPT should be applied. In addition, strategy to minimize bleeding complications is highly recommended. Several risk scores have been reported to discriminate the risk and benefits of DAPT. However, in general, bleeding risk and event risk are correlated with each other, thus predictability of these scores is limited to moderate. Therefore, interpretation of previous trials is important to overcome the shortcome in outcomes. In this review, we provide an overview of DAPT trials and clarify the shortfalls to consider in Japan. Finally, possible future trends with reference to the results of recent clinical trials will be presented.

Safety and efficacy of clopidogrel treatment in Japanese patients undergoing drug-eluting stent implantation.

BACKGROUND: Clopidogrel has been utilized as an antiplatelet therapy for patients undergoing stent implantation. In the Japanese population, however, the impact of clopidogrel on the occurrence of early adverse events is unknown. This study sought to evaluate procedural major bleeding and myocardial infarction in patients undergoing stent implantation with adjunctive clopidogrel compared with ticlopidine. METHODS AND RESULTS: The retrospective analysis included 311 patients who had stent implantation between January 2007 and April 2009. The patients were divided into groups with clopidogrel (n=159) and ticlopidine (n=152). Primary endpoint was major bleeding and myocardial infarction at 30 days. The incidence of major bleeding was 4.4% in the clopidogrel group vs. 3.9% in the ticlopidine group (p=0.94). The incidence of myocardial infarction was 3.8% in the clopidogrel group vs. 7.9% in the ticlopidine group (p=0.19). In patients with unstable angina, however, there was a strong trend toward lower incidence of myocardial infarction in patients treated with clopidogrel than those treated with ticlopidine (4.1% vs. 13.3%, p=0.08). The incidence of major bleeding was no different (1.4% vs. 5.3%, p=0.37). CONCLUSIONS: In patients with unstable angina and emergent coronary intervention, adjunctive clopidogrel therapy may have a slight positive impact on the prevention of myocardial infarction without increasing the risk of bleeding complications.