Impact of high loading and maintenance dose of clopidogrel within the first 15 days after percutaneous coronary intervention on patient outcome.

BACKGROUND: An increase in clopidogrel dose results in an improved inhibition of platelet aggregation. However, whether an increase in clopidogrel dose may improve patient outcome is still debated. The aim of this study was to analyze the impact on patient outcome of an increase in clopidogrel loading and maintenance doses within the first 15 days after percutaneous coronary intervention (PCI). METHODS: Between 2003 and 2007, we included 2,954 consecutive patients who underwent PCI and stent implantation. We compared 2 historical groups. In the "low-dose" group (2003-2005, n = 1,984), patients were pretreated with a 300-mg clopidogrel loading dose followed by 75 mg/d after PCI. In the "high-dose" group (2006-2007, n = 970), patients were pretreated with a 600-mg clopidogrel loading dose followed by 150 mg/d within the first 15 days and 75 mg/d thereafter. The composite primary end point (death, myocardial infarction, stent thrombosis) and bleeding were systematically indexed during the 2-month follow-up period. RESULTS: Clinical and most of angiographic characteristics were similar between the 2 groups. By multivariate analysis, high dose of clopidogrel was associated with a decrease in the composite primary end point (hazard ratio 0.694, 95% CI 0.485-0.993, P = .046). The other predictors were age, left ventricular ejection fraction, diabetes, renal failure, and acute coronary syndrome. Major bleeding was similar in the low- and high-dose groups (2.8% vs 3.4%, respectively, P = .379). After propensity score matching, the high-dose group was still associated with a significant clinical benefit. CONCLUSION: Our results show that a 600-mg loading dose followed by a 150-mg maintenance dose of clopidogrel within the first 15 days after PCI is independently associated with a decrease in the composite death-myocardial infarction-stent thrombosis at 2 months without increase in hemorrhagic complications.

Preprocedural high-sensitivity C-reactive protein predicts death or myocardial infarction but not target vessel revascularization or stent thrombosis after percutaneous coronary intervention.

BACKGROUND: High-sensitivity C-reactive protein (hs-CRP) elevation is associated with poor clinical outcome in patients with coronary artery disease (CAD). However, the prognostic value of preprocedural hs-CRP elevation before coronary stent implantation remains debated especially regarding restenosis and target vessel revascularization (TVR). Furthermore, whether hs-CRP elevation may predict stent thrombosis (ST) is unknown. METHODS: We included 560 consecutive patients, who underwent coronary stent implantation in our institution. Blood samples for hs-CRP determination were obtained immediately before the procedure. During a median follow-up of 12.5 months, cardiovascular events including death, myocardial infarction (MI), TVR, and ST were systematically included. RESULTS: Median hs-CRP was 3.10 [25-75th percentile: 1.36-8.63] mg/l. There were 27 (4.8%) deaths, 17 (3.1%) nonfatal MI, 58 (10.5%) TVR, and 12 (2.1%) ST. The composite criteria death-MI occurred in 44 (7.9%) patients. Independent predictors of the composite death-MI were hs-CRP level [hazard ratio (HR)=1.33 (95% CI: 1.05-1.70); P=.021], diabetes (P=.003), and multivessel CAD (P=.011). The composite death-MI occurred in 31 (13.3%) of the 233 patients with hs-CRP >4.63 mg/l vs. 13 (4.0%) of the 327 patients with hs-CRP <4.63 mg/L (P<.001). By contrast, hs-CRP predicted neither TVR [HR=0.88 (0.73-1.08); P=.23] nor ST [HR=1.15 (0.77-1.71); P=.49]. CONCLUSION: High hs-CRP levels before coronary stent implantation are associated with risk of death or MI, but are not related to TVR or ST. These data suggest that preprocedural hs-CRP is more a predictor of global cardiovascular risk than a predictor of stent-related complications.