Sabatine MS et al. (2005) Effect of clopidogrel pretreatment before percutaneous coronary intervention in patients with ST-elevation myocardial infarction treated with fibrinolytics: the PCI–CLARITY study. JAMA 294: 1224–1232

Following percutaneous coronary intervention (PCI), antiplatelet therapy in the form of aspirin alone or dual therapy with aspirin and clopidogrel can lower the risk of adverse thrombotic and ischemic events. Whether treatment with clopidogrel before PCI prevents more complications than clopidogrel administered at the time of PCI in patients with ST-segment elevation myocardial infarction (STEMI) who have received fibrinolytic therapy is, however, unclear.

The PCI–Clopidogrel as Adjunctive Reperfusion Therapy (CLARITY) study was a prospective substudy of patients with STEMI who underwent PCI following initial fibrinolytic pharmacotherapy in the CLARITY–Thrombolysis in Myocardial Infarction (TIMI) 28 study. Patients were randomly assigned placebo or a loading dose of 300 mg clopidogrel administered in the 45 min after fibrinolysis followed by 75 mg clopidogrel daily.

Of the 1,863 patients who underwent PCI, 933 received clopidogrel and 930 received placebo. On the basis of intention to treat, the overall occurrence of stroke, recurrent myocardial infarction or cardiovascular-related mortality, from randomization to 30-day follow-up, was significantly lower in patients who had received clopidogrel pretreatment than in patients who received placebo (70 versus 112; number needed to treat 23, odds ratio 0.59, 95% CI 0.43–0.81; P = 0.001). Importantly, clopidogrel pretreatment did not raise the risk of bleeding complications.

The authors conclude that clopidogrel should be administered before PCI in patients with STEMI treated with fibrinolytic therapy.