de Winter R J, Koster R W, Sturk A, Sanders G T
Department of Cardiology, University of Amsterdam The Netherlands.
Circulation. 1995 Dec 15;92(12):3401-7. doi: 10.1161/01.cir.92.12.3401.
Ruling out acute myocardial infarction (AMI) on the basis of rapid assays for cardiac markers will allow early triage of patients and cost-effective use of available coronary care facilities.
We studied the value of myoglobin, creatine kinase (CK)-MBmass, and troponin T in ruling out an AMI in the emergency room in 309 consecutive patients presenting with chest pain. The gold standard for AMI was the combination of history, ECG, and a typical curve of the CK-MB activity (CK-MBact). Myoglobin was the earliest marker, and its negative predictive value (NPV) was significantly higher than for CK-MBmass and troponin T from 3 to 6 hours after the onset of symptoms (myoglobin versus CK-MBmass, P < .03; myoglobin versus troponin T, P < .01). The NPV of myoglobin reached 89% 4 hours after the onset of symptoms. The NPV of CK-MBmass reached 95% 7 hours after the onset of symptoms. Troponin T was not an early marker for ruling out AMI, and NPV changed over time, together with CK-MBact. The early NPV was higher in a subgroup of patients with a low probability of the presence of AMI for the three markers. Cardiac markers rise earlier in patients with large infarcts than in patients with small infarcts as indicated by the cumulative proportion of the marker above the upper reference limit at each time point (myoglobin, P = .04; CK-MBmass, P = .013; troponin T, P = .016).
For ruling out AMI in the emergency room, myoglobin is a better marker than CK-MBmass or troponin T from 3 until 6 hours after the onset of symptoms, but the maximal NPV reaches only 89%. At 7 hours, the NPV of CK-MBmass is 95%. The test characteristics are influenced by the probability of the presence of AMI in the patients studied and by the size of their AMI. Infarct size of AMI patients should be reported in studies evaluating cardiac markers.
基于心脏标志物的快速检测来排除急性心肌梗死（AMI），将有助于对患者进行早期分诊，并实现对现有冠心病监护设施的成本效益利用。
我们研究了肌红蛋白、肌酸激酶（CK）-MB质量和肌钙蛋白T在连续309例胸痛患者的急诊室中排除AMI的价值。AMI的金标准是病史、心电图以及CK-MB活性（CK-MBact）的典型曲线相结合。肌红蛋白是最早出现的标志物，在症状发作后3至6小时，其阴性预测值（NPV）显著高于CK-MB质量和肌钙蛋白T（肌红蛋白与CK-MB质量相比，P <.03；肌红蛋白与肌钙蛋白T相比，P <.01）。症状发作后4小时，肌红蛋白的NPV达到89%。症状发作后7小时，CK-MB质量的NPV达到95%。肌钙蛋白T不是排除AMI的早期标志物，其NPV随时间变化，与CK-MBact情况相同。在三种标志物提示AMI可能性较低的患者亚组中，早期NPV更高。如每个时间点标志物高于参考上限的累积比例所示，大面积梗死患者的心脏标志物升高早于小面积梗死患者（肌红蛋白，P =.04；CK-MB质量，P =.013；肌钙蛋白T，P =.016）。
对于在急诊室排除AMI，症状发作后3至6小时，肌红蛋白是比CK-MB质量或肌钙蛋白T更好的标志物，但最大NPV仅达到89%。7小时时，CK-MB质量的NPV为95%。检测特征受所研究患者中存在AMI的概率及其AMI大小的影响。在评估心脏标志物的研究中应报告AMI患者的梗死面积。
