Efficacy of clopidogrel reloading in patients with acute coronary syndrome undergoing percutaneous coronary intervention during chronic clopidogrel therapy (from the Antiplatelet therapy for Reduction of MYocardial Damage during Angioplasty [ARMYDA-8 RELOAD-ACS] trial).

Whether an additional clopidogrel load in patients receiving chronic clopidogrel therapy and undergoing percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) is associated with clinical benefit has not been well characterized. The aim of the present study was to evaluate, in a randomized protocol, the safety and effectiveness of clopidogrel reload for patients with ACS undergoing PCI in the background of chronic clopidogrel therapy. A total of 242 patients with non-ST-segment elevation ACS with >10 days of clopidogrel therapy randomly received a 600-mg loading dose of clopidogrel 4 to 8 hours before PCI (n = 122) or placebo (n = 120). The primary end point was the 30-day incidence of major adverse cardiac events (death, myocardial infarction, target vessel revascularization). The primary end point occurred in 4.1% of patients in the reload arm versus 14.1% in the placebo arm (odds ratio 0.26, 95% confidence interval 0.10 to 0.73, p = 0.013). This benefit in the reload arm was mainly from the prevention of periprocedural myocardial infarction (4.1% vs 13%, p = 0.02) and was paralleled by lower periprocedural platelet reactivity. The aggregometry data were consistent with the clinical outcome. No difference was found in the bleeding outcomes between the 2 groups. In conclusion, the results from the Antiplatelet therapy for Reduction of MYocardial Damage during Angioplasty (ARMYDA-8 RELOAD-ACS) trial have shown a significant clinical benefit from reloading patients with ACS receiving chronic clopidogrel therapy before PCI. These data might be relevant in clinical practice, given the large number of patients with ACS who are still currently treated with clopidogrel during PCI.