ABSTRACT
Objective To observe the current status of secondary prevention medication usage and their relation with on-treatment platelet reactivity in patients with Acute Coronary Syndrome(ACS) treated with aspirin and clopidogrel. Methods A total of 176 patients hospitalized from 2014 to 2015 due to ACS in the Department of Cardiology, Peking University People's Hospital were enrolled and on-treatment platelet reactivity was tested by thromboelastography(TEG)and CYP2C19*2,*3 and*17 alleles were analysed. Details of secondary prevention medication and patients' clinical characteristics were recorded. The relation of secondary prevention medication and on-treatment platelet reactivity was analyzed by multi-logistic regression after adjusting for CYP2C19 alleles and clinical characteristics covariates.Results A 94.89% of patients was treated with statins while 80.68% with beta blocker. The platelet inhibition rate were (45.33±28.78)% and the high on-treatment platelet reactivity (HTPR) rate tested by TEG was 37.50%. In the multivariate logistic regression analysis, usage of β-blockers during hospitalization as well as phenotypes of CYP2C19*2,*3 and *17,clinical presentation with ST-segment elevation myocardial infarction and the length of stents were associated with HTPR defi ned by TEG. The percentage of HTPR rate was signifi cantly lower in patients treated with than those without β-blockers (72.73% vs. 85.45%,OR 0.18,95%CI 0.06-0.53,P=0.002)after adjusting genetic factors and other covariates.Conclusions There was a signifi cant correlation between beta blockers usage and high clopidogrel on-treatment platelet reactivity.