Abstract:Objective To investigate the relationship between the drug responsiveness of clopidogrel and CYP2C19 gene polymorphism after percutaneous coronary intervention (PCI) in patients with coronary heart disease. Methods A total of 231 patients diagnosed as coronary heart disease and treated with clopidogrel after PCI from January to July 2018 were selected.According to CYP2C19 gene polymorphism,all cases were divided into fast metabolic type (Group A,n=78),intermediate metabolic type (Group B,n=126) and slow metabolic type(Group C,n=27).The inhibition rate of adenosine diphosphate (ADP)-induced platelets (<30% defined as clopidogrel hyporeactivity) and the maximum strength of ADP (MAADP) channel blood clots (>47 mm) were detected by thromboelastography.Using SPSS statistical analysis,the differences in inhibition rate,the proportions of clopidogrel hyporeactivity and MAADP were analyzed among three groups. Results ADP-induced platelet inhibition rate were(77.04±23.38)%,(75.30±28.67)%,(79.78±28.29)%respectively in group A,group B and group C,and there were no statistical differences among three groups (P>0.05).There were no statistical differences in the proportion of patients with clopidogrel hyporeactivity (3.8% vs 10.3% vs 7.4%) and the proportion of MAADP>47 mm ( 3.85% vs 10.32% vs 3.70%) among three groups( all P>0.05 ). Conclusion There is no significant correlation between CYP2C19 gene polymorphism and clopidogrel efficacy after PCI for coronary heart disease.