Correlation between clopidogrel dose and cardiac adverse events in patients with loss of CYP2C19 genotype function after PCI

Objective To study the correlation between clopidogrel dose and cardiac adverse events in patients with loss of CYP2C19genotype function after PCI.Methods CYP2C19was detected in 280patients receiving continuous clopidogrel treatment.One hundred and fifty of them with loss of CYP2C19gene function were randomly divided into 75mg/d clopidogrel treatment group(n=75)and 150mg/d clopidogrel treatment group(n=75).Another 130patients with normal CYP2C19metabolism receiving 75mg/d clopidogrel served as a control group.Their platelet inhibition rate was measured 1day and 1and 3months after PCI according to their thrombus elastic graph.Results The platelet inhibition rate was significantly lower in 75mg/d clopidogrel treatment group than in 150mg/d clopidogrel treatment group 1and 3months after PCI(38.3%± 12.8%vs 51.7%±15.6%,30.5%±18.2%vs48.3%±21.3%,P0.05).Acute myocardial infarction and stent thrombosis occurred respectively in 3patients of 75mg/d clopidogrel treatment group.No recurrent ischemic cardiovascular event occurred in 150 mg/d clopidogrel treatment group.Conclusion The platelet inhibition rate of clopidogrel(150mg/d)is significantly higher than that of clopidogrel(75mg/d),and can thus reduce the major cardiac adverse events,such as stent thrombosis and nonfatal myocardial infarction,in patients with loss of CYP2C19genotype function after PCI.