Wu A H, Valdes R, Apple F S, Gornet T, Stone M A, Mayfield-Stokes S, Ingersoll-Stroubos A M, Wiler B
Department of Pathology, Hartford Hospital, CT.
Clin Chem. 1994 Jun;40(6):900-7.
We evaluated the analytical and clinical performance of an immunoassay for cardiac troponin T (cTnT). Within-run and total imprecision ranged from 1.6 to 11.3%. The sensitivity and linear range was 0.015 and 13 micrograms/L, respectively. Frozen samples were stable for at least 8 weeks. No interferences were seen with lipids or bilirubin (total and conjugated). Hemoglobin caused a negative bias at concentrations > 4 g/L. Heparinized plasma showed a 6% negative bias compared with serum. The clinical utility of cTnT was compared with that of creatine kinase (CK)-MB (mass assay). The sensitivity of cTnT measurements from 63 patients with acute myocardial infarction (AMI) (cTnT cutoff 0.1 microgram/L) was 60% at 0-3 h, 59% at 3-6 h, 94% at 6-9 h, 90% at 9-12 h, 99% at 12-24 h, 92% at 24-48 h, 83% at 48-72 h, and 100% at 72-96 h. Corresponding results for CK-MB (cutoff 5.0 micrograms/L and 2.5% relative index) were 45%, 64%, 82%, 97%, 87%, 81%, 54%, and 59%. The specificity of the markers from 49 non-AMI patients was 46% and 79% for cTnT and CK-MB, respectively. We show that CK-MB is more specific for diagnosis of AMI, and propose that cTnT is more sensitive to myocardial injury.
我们评估了一种心肌肌钙蛋白T（cTnT）免疫测定法的分析性能和临床性能。批内和总不精密度范围为1.6%至11.3%。灵敏度和线性范围分别为0.015微克/升和13微克/升。冷冻样本至少稳定8周。未观察到脂质或胆红素（总胆红素和结合胆红素）的干扰。血红蛋白浓度>4克/升时会导致负偏差。与血清相比，肝素化血浆显示出6%的负偏差。将cTnT的临床效用与肌酸激酶（CK）-MB（质量测定法）的临床效用进行了比较。对63例急性心肌梗死（AMI）患者（cTnT临界值为0.1微克/升）进行cTnT测量的灵敏度在0至3小时为60%，3至6小时为59%，6至9小时为94%，9至12小时为90%，12至24小时为99%，24至48小时为92%，48至72小时为83%，72至96小时为100%。CK-MB（临界值为5.0微克/升和相对指数为2.5%）的相应结果分别为45%、64%、82%、97%、87%、81%、54%和59%。49例非AMI患者的标志物特异性，cTnT为46%，CK-MB为79%。我们表明，CK-MB对AMI诊断更具特异性，并提出cTnT对心肌损伤更敏感。
