Reaction of Clopidogrel,Flow Cytometry and Thrombelastogram in Detecting Coronary Heart Disease after Percutaneous Coronary Intervention

Objective To explore flow cytometry and Thrombelastogram( TEG) testing value in evaluation of low response to clopidogrel. Methods Eighty- nine patients with coronary heart disease( CHD) admitted to Fuxing Hospital from February to December 2011 were enrolled in study group,29 healthy subjects in control group. After 1- week administration of clopidogrel and aspirin,flow cytometry and TEG were used to detect clopidogrel response,flow cytometry to test platelet activated receptor maker PAC- 1 and CD62 p,TEG to test ADP inhibition rate which reflected the clopidogrel effect. The incidences of ischemia and bleeding events within 1 year were followed up. Results The expressions of platelet activation markers were calculated according to interquartile range method. Defining platelet activation marker CD62 p 15. 5% and PAC- 1 3. 01% as high expression of platelet activation,the response to clopidogrel was low; platelet activation marker CD62 p 15. 5% or PAC- 1 3. 01% for moderate expression of activated platelets; defining CD62 P 15. 5% or PAC- 1 3. 01% as medium expression or as low expression,the response to clopidogrel was better. When ADP inhibition ratio was 38. 9%,the sensitivity was 97. 0%,specificity 61. 1%,the area under ROC curve was 0. 932( P = 0. 001). Forty- six patients had high expression,43 had medium,no patients had low expression. Combined with ADP inhibition rate 38. 9%,40 patients had low response to clopidogrel.There was no significant difference in incidences of major ischemia and bleeding events between patients with low,medium responses( P 0. 05). Only 4 patients had mild bleeding events,mainly local subcutaneous hemorrhage,gum bleeding,subhyaloid hemorrhage. Conclusion The critical value of TEG detecting low response to clopidogrel is ADP 38. 9%,suggesting that patients may have drug resistance,which provides references for further researches.