心肌肌钙蛋白Ⅰ在非ST段抬高急性冠状动脉综合征诊断和预后中的临床应用

Evaluation of clinical performance of cardiac troponin Ⅰ in diagnosis and prognosis of non-ST elevation acute coronary syndromes

目的评价心肌肌钙蛋白Ⅰ(cTnI)对非 ST 段抬高心肌梗死(NSTEMI)的诊断价值,并探讨其与非 ST 段抬高急性冠状动脉综合征(NSTEACS)近期和远期预后的关系。方法 cTnI 测定采用新一代 Beckman Coulter AccuTnI 化学发光试剂盒;应用操作者工作特征曲线(ROC 曲线)分析 cTnI对 NSTEMI 的诊断的敏感度和特异度;同时应用ROC曲线比较不同生化标志物对 NSTEMI 诊断价值;将269例 NSTEACS 患者以 cTnI 水平0.04μg/L 为分界点进行分组,比较 cTnI 升高组和 cTnI 正常组30 d 内和1年内急性心肌梗死和/或心源性死亡事件的发生情况。结果 ROC 曲线分析结果显示诊断 NSTEMI 的最佳 cut-off 值为0.1μg/L,此界值诊断的敏感度和特异度为91.4%和89.3%;肌酸激酶及其同工酶 MB、乳酸脱氢酶和α-羟丁酸脱氢酶各指标的诊断敏感度和特异度均低于 cTnI;单因素分析显示 cTnI 升高组30 d 内和1年内复合心脏事件的发生率(3.61%和6.02%)较 cTnI 正常组(均为0)显著升高(P<0.05);多因素分析显示校正高血压、糖尿病、高脂血症、陈旧心肌梗死、心电图改变等危险因素后,cTnI 升高是30 d 内发生复合心脏事件的独立危险因子,风险比值(OR)=8.175,95%可信区间(CI)为1.014～65.917,P=0.049;也是1年内发生复合心脏事件的独立预告因子,OR=2.612,95% CI 为1.164～5.859,P=0.02。结论 Beckman 公司出品的 cTnI 对 NSTEMI 的诊断具有较高的敏感度和特异度,对 NSTEACS 患者的预后判断具有重要价值。

Objective To evaluate the sensitivity and specificity of new genevation Beckman Coulter cTnI in diagnosis of non-ST-elevation myocardial infarction （ NSTEMI）, and the values of cTnI in prognosis of non-ST elevation acute coronary syndromes （NSTEACS）. Methods The cTnI was determined in NSTEMI patients and in control group, then analyzed the data with receiver operating characteristic curve （ROC curve） statistical software. Two hundred and sixty-nine patients with non-ST elevation acute coronary syndromes were divided into cTnI≥0. 04μg/L and cTnI 〈0. 04 μg/L. Acute myocardial infarction and/or cardiac mortality were observed in all patients through both 30 days and 1 year of follow-up. Results The area under the ROC curve was 0. 95. The optimal cut-off was 0. 1μg/L in the diagnosis of NSTEMI and the sensitivity and specificity was 91.4% and 89.3%. The sensitivities and specificities of creatine kinase, creatine kinase MB,lactate dehydrogenase and α-hydroxybutyrate dehydrogenase were less poor than that of cTnI. By univariate analysis, the incidence of composite endpoints through 30 days and 1 year of follow-up was significantly higher in the abnormal group than in the normal group （ P 〈 0. 05 ）. By multivariate analysis, adjusted for hypertension, diabetes mellitus, hyperlipaemia, previous MI, electrocardiogram （ECG） changes and etc. , high cTnI maintained a strong association with the risk of composite cardiac events through 30 days of follow-up[ odds ratio（ OR）, 8. 175 ; 95% confident interval （ CI）, 1. 014-65. 917 ; P 〈0. 05] as well as through 1 year of follow-up（OR, 2.612; 95% CI, 1.164-5.859; P 〈 0.05） in all three groups. Conclusions We have testified Beckman Coulter ACCESS AccuTnI assay had high sensitivity and specificity in the diagnosis of NSTEMI. Detection of plasma cTnI is of clinical value for prognosis of NSTEACS.