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目的 评估床边敏感性肌钙蛋白Ⅰ(point-of-care testing for sensitive cardiac troponin Ⅰ,POCT-cTnⅠ)对早期诊断急性心肌梗死(acute myocardial infarction,AMI)的分析性能.方法 检测中山大学附属第一医院急诊科收治的127例疑诊AMI的急诊胸痛患者在入院3个不同时间点(入院即刻、入院后3h和6h)POCT-cTnI和中心实验室高敏肌钙蛋T(central laboratory testing for high sensitive cardiac troponin T,CLT-hscTnT)水平,由两名临床医师根据90 d内所获得的全部临床资料各自独立地给出胸痛病因的最终诊断,并将患者分为AMI组和非AMI组.应用受试者工作特征曲线(receiver operating characteristic curve,ROC曲线)比较POCT-cTnI和CLT-hscTnT两种检测方法对AMI的诊断性能,采用DeLong检验比较ROC曲线下面积(area under the curve,AUC);并计算使用不同诊断界值时的敏感性、特异性、阴性预测值(negative predictive value,NPV)和阳性预测值(positive predictive value,PPV).结果 127例胸痛患者中,有40例(31.5％)最终诊断为AMI.POCT-cTnI和CLT-hscTnT在入院即刻水平诊断AMI的准确性用AUC表示,分别为0.901 (95％CI:0.901～0.947)和0.907 (95％CI:0.842～0.951),两者差异无统计学意义(Z=0.235,P=0.745).POCT-cTn在入院后3h的AUC增加至0.931,与入院即刻相比(AUC,0.858)差异有统计学意义(Z=-2.038,P=0.042),但较入院后6 h(AUC,0.949)差异无统计学意义(Z=-1.435,P=0.151).POCT-cTn使用正常人群参考范围上限的第99百分位数为诊断界值(0.023 ng/mL),入院即刻水平的诊断敏感性为77.5％,特异性为94.2％;入院后3h诊断特性进一步提高,敏感性为96.4％,特异性为92.0％,NPV为98.6％,PPV为81.8％.而CLT-hscTnT使用第99百分位数为诊断界值(0.014 ng/mL),在入院3h水平的NPV为100％.结论 POCT-cTnI可在急诊胸痛患者入院后3h快速准确地识别或除外AMI,诊断性能与CLT-hscTnT相近.“,”Objective To evaluate the diagnostic performance of a point-of-care testing for sensitive cardiac troponin Ⅰ (POCT-cTnI) in early diagnosis of chest pain patients who had a high pretest probability of acute myocardial infarction (AMI).Methods Total of 127 patients with new-onset chest pain at the emergency department were enrolled.Blood samples were drawn for the routine blood test,and determined POCT-cTnI and central laboratory testing for high sensitive cardiac troponin T (CLT-hscTnT) at admission,three and then at six hours after admission.All patients were divided into AMI group and non-AMI group according to the final diagnosis,which was adjudicated independently by two physicians who reviewed all available medical records for the 90-day follow-up period,and they were unaware of the results of the investigational assays of cardiac troponins.The receiver operating characteristic (ROC) curves were constructed to assess and compare the diagnostic performance of AMI of two cardiac troponin assays.The comparison of areas under the ROC curves (AUC) was performed by DeLong test,and the sensitivity,specificity,negative predictive values (NPV) and positive predictive values (PPV) for the target markers were calculated by applying a maker-specific cutoff value.Results The final diagnosis of AMI was made in 40 of 127 patients (31.5 ％).The diagnostic accuracy of the two assays oBtained at presentation,as quantified by AUC,was no statistically differences (AUC for POCT-cTnⅠ,0.901,95％ CI,0.901 to 0.947;and for CLT-hscTnT,0.907,95％ CI,0.842 to 0.951;Z =0.235,P =0.745).The AUC for POCT-cTnI at 3 hours after admission was significantly higher than that on admission (0.931 vs.0.858;Z =-2.038,P =0.042),while there was on further improvement at 6 hours after admission (0.931 vs.0.949;Z =-1.435,P =0.151).With use of POCT-cTnI (cutoff value 0.023 ng/mL,which was the 99th percentile upper reference limit) on adimission,the clinical sensitivity was 77.5％,and the specificity was 94.2％.A single sample of POCT-cTnI at 3 hours after admission improved the diagnostic accuracy,with a sensitivity of 96.4％,a specificity of 92.0％,and a NPV of 98.6％,a PPV of 81.8％.While,with use of CLT-hscTnT (cutoff value 0.014 ng/mL,was the 99th percentile upper reference limit) at 3 hours after admission,the NPV reached to 100％.Conclusions The use of a POCT-cTnI assay in chest pain patients can identify and exclude the AMI rapidly and exactly at three hours after admission,and the diagnostic performance is equivalent to CLT-hscTnT.