Effect of clopidogrel pretreatment before percutaneous coronary intervention in patients with ST-elevation myocardial infarction treated with fibrinolytics: the PCI-CLARITY study

Abstract

Context: The benefit of clopidogrel pretreatment before percutaneous coronary intervention (PCI) remains debated and its use has not been universally adopted.

Objective: To determine if clopidogrel pretreatment before PCI in patients with recent ST-segment elevation myocardial infarction (STEMI) is superior to clopidogrel treatment initiated at the time of PCI in preventing major adverse cardiovascular events.

Design, setting, and participants: The PCI-Clopidogrel as Adjunctive Reperfusion Therapy (CLARITY) study was a prospectively planned analysis of the 1863 patients undergoing PCI after mandated angiography in CLARITY-Thrombolysis in Myocardial Infarction (TIMI) 28, a randomized, double-blind, placebo-controlled trial of clopidogrel in patients receiving fibrinolytics for STEMI. Patients were enrolled at 319 sites in 23 countries from February 2003 through October 2004.

Interventions: Patients received aspirin and were randomized to receive either clopidogrel (300 mg loading dose, then 75 mg once daily) or placebo initiated with fibrinolysis and given until coronary angiography, which was performed 2 to 8 days after initiation of the study drug. For patients undergoing coronary artery stenting, it was recommended that open-label clopidogrel (including a loading dose) be administered after the diagnostic angiogram.

Main outcome measures: The primary outcome was the incidence of the composite of cardiovascular death, recurrent MI, or stroke from PCI to 30 days after randomization. Secondary outcomes included MI or stroke before PCI and the aforementioned composite from randomization to 30 days.

Results: Pretreatment with clopidogrel significantly reduced the incidence of cardiovascular death, MI, or stroke following PCI (34 [3.6%] vs 58 [6.2%]; adjusted odds ratio [OR], 0.54 [95% CI, 0.35-0.85]; P = .008). Pretreatment with clopidogrel also reduced the incidence of MI or stroke prior to PCI (37 [4.0%] vs 58 [6.2%]; OR, 0.62 [95% CI, 0.40-0.95]; P = .03). Overall, pretreatment with clopidogrel resulted in a highly significant reduction in cardiovascular death, MI, or stroke from randomization through 30 days (70 [7.5%] vs 112 [12.0%]; adjusted OR, 0.59 [95% CI, 0.43-0.81]; P = .001; number needed to treat = 23). There was no significant excess in the rates of TIMI major or minor bleeding (18 [2.0%] vs 17 [1.9%]; P>.99).

Conclusions: Clopidogrel pretreatment significantly reduces the incidence of cardiovascular death or ischemic complications both before and after PCI and without a significant increase in major or minor bleeding. These data add further support to the early use of clopidogrel in STEMI and the strategy of routine clopidogrel pretreatment in patients undergoing PCI.