- 作者：Gerald Yong ; Jamie Rankin ; Louise Ferguson ; Jim Thom ; John French ; David Brieger ; Derek P. Chew ; Ron Dick ; David Eccleston ; Bernard Hockings ; Darren Walters ; Alan Whelan ; John W. Eikelboom
- 刊名：American Heart Journal
- 出版年：2009
- 出版时间：January 2009
- 年：2009
- 卷：157
- 期：1
- 页码：60.e1-60.e9
- 全文大小：491 K
Background
There is uncertainty about the benefit of a higher loading dose (LD) of clopidogrel in patients with non–ST elevation acute coronary syndrome (NSTEACS) undergoing early percutaneous coronary intervention (PCI).Methods
We compared the effects of a 600- versus a 300-mg LD of clopidogrel on inhibition of platelet aggregation, myonecrosis, and clinical outcomes in patients with NSTEACS undergoing an early invasive management strategy. Patients with NSTEACS (n = 256, mean age 63 years, 81.6 % elevated troponin) without thienopyridine for at least 7 days were randomized to receive 600- or 300-mg LD of clopidogrel. Percutaneous coronary intervention was performed in 140 patients, with glycoprotein IIb/IIIa inhibitor use in 68.6 % . Adenosine diphosphate (ADP)–induced platelet aggregation was measured by optical platelet aggregometry immediately before coronary angiography.
Results
Post-PCI myonecrosis was defined as a next-day troponin I greater than 5 times the upper limit of reference range and greater than baseline levels. Clopidogrel 600-mg LD compared with 300-mg LD was associated with significantly reduced ADP-induced platelet aggregation (49.7 % vs 55.7 % with ADP 20 μmol/L) but did not reduce post-PCI myonecrosis or adverse clinical outcomes to 6 months. There was no association between preprocedural platelet aggregation and outcome.
Conclusions
These data confirm a modest incremental antiplatelet effect of a 600-mg clopidogrel LD compared with 300-mg LD but provide no support for a clinical benefit in patients with NSTEACS managed with an early invasive strategy including a high rate (69 % ) of glycoprotein IIb/IIIa inhibitor use during PCI.