An investigation on the influencing factors of clopidogrel resistance in patients with acute coronary syndrome

Objective To evaluate the occurrence and the possible influencing factors of clopidogrel resistance in patients with acute coronary syndrome(ACS). Methods All patients were treated with aspirin 100 mg/d and received a loading dose of 300 mg clopidogrel followed by a maintenance dose of 75 mg/d,Platelet aggregation induced by ADP with a concentration of 25 μmol/L was measured before and 24 hour after clopidogrel intake, and the inhibition of platelet aggregation (△A)was calculated,△A≤10%(including negative value) is considered as clopidogrel resistance. Results 102 patients with ACS were selected, there is 43 patients with the inhibition of platelet aggregation ≤10%,with the percentage of 42.2%. Conclusion A subgroup of patients with ACS and PCI aperas clopidogrel resistance in the antithrombotic therapy, the occurrence of clopidogrel resistance increases in the patients with acute non-ST segment elevation myocardial infarction and coronary stsnting.