BACKGROUND:The predictive scoring systems for early stent thrombosis(EST)remains blank in China.The study aims to evaluate the risk factors and conduct a prediction model of EST in the Chinese population.METHODS:EST was defined as thrombosis that occurs within the first 30 days after primary percutaneous coronary intervention(PCI).Patients from ten Chinese hospitals diagnosed as stent thrombosis(ST)from January 2010 to December 2016 were retrospectively included as the study group.A control group(1 case:2 controls)was created by including patients without ST,major adverse cardiovascular events,or cerebrovascular events during follow-up.The present study evaluated 426 patients with single-vessel lesions and ultimately included 40 patients with EST and 80 control patients,who were included to identify factors that predicted EST and to develop a prediction scoring system.The other 171 patients without integrated 1:2 pair were used for external validation.RESULTS:EST was independently associated with a low hemoglobin concentration(adjusted odds ratio[OR]0.946,95％confidence interval[95％Cl]0.901-0.993,P=0.026),a high pre-PCI Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery(SYNTAX)score(OR 1.166,95％Cl 1.049-1.297,P=0.004),and a DAPT(DAPT)duration of＜30 days(OR 28.033,95％CI 5.302-272.834,P＜0.001).The simple EST prediction score provided an area under the curve(AUC)of 0.854(95％CI 0.777-0.932,P＜0.001)with 70.0％sensitivity and 90.0％specificity,and 0.742(95％CI 0.649-0.835,P＜0.001)with 54.5％sensitivity and 81.0％specificity for external validation dataset.CONCLUSIONS:EST may be independently associated with DAPT discontinuation within 30 days,a low hemoglobin concentration,and a high SYNTAX score.The scoring system also has a good ability to predict the risk of EST and may be useful in the clinical setting.