目的:高敏心肌肌钙蛋白T和I(hs-cTnT和hs-cTnI)分析显示,与当代敏感的cTn测定相比,诊断和预后的改善。然而,考虑到肌钙蛋白在心肌梗死诊断中的重要性,实施此测试需要在整个测试路径中进行严格的分析和临床验证。这就是本研究的目的。
方法:分析验证包括评估关键离群频率,用于hs-cTnI和cTnI测定。使用两种性别的第99个百分位数验证了配对cTnI和hs-cTnI测量值(n=1096)的一致性(cTnI:30ng/L,hs-cTnI:25ng/L),男女分别适用(hs-cTnI:M:34;F:16ng/L)。不一致的数据与临床和实验室信息相关。急性冠状动脉综合征(ACS)或非ACS的诊断由两名心脏病专家独立裁定。
结果:hs-cTnI测定显示较低(10倍)的临界离群率(0.091%)和高于检测限(LOD)(23.4%)和第99百分位数(2.4%)的更多可检测结果,与cTnI相比。两种测定之间的分析一致性很高(94.5%),但当使用性别特异性hs-cTnI截止值时降低(91.7%)。hs-cTnI分析给出了较少的假阴性(高达1.0%),但不成比例地更多的假阳性(高达6.7%)。这在串行测量方面有所改善(3.9%)。
结论:实验室应在使用前进行分析和临床验证hs-cTn测定,注意性能以及支持适当测试和结果解释的临床和诊断算法。在分析前和分析后阶段的工作对于在肌钙蛋白测试的新时代中增强分析改进是必要的。
OBJECTIVE: High sensitivity cardiac troponin T and I (hs-cTnT and hs-cTnI) assays show analytical, diagnostic and prognostic improvement over contemporary sensitive cTn assays. However, given the importance of troponin in the diagnosis of myocardial infarction, implementing this test requires rigorous analytical and clinical verification across the total testing pathway. This was the aim of this study.
METHODS: Analytical verification included assessment of critical outlier frequency, for hs-cTnI and cTnI assays. Concordance for paired cTnI and hs-cTnI measurements (n=1096) was verified using 99th percentiles for both genders (cTnI: 30 ng/L, hs-cTnI: 25 ng/L) and for men and women separately (hs-cTnI: M: 34;F: 16 ng/L). Discordant data was correlated with clinical and laboratory information. Diagnosis of Acute Coronary Syndrome (ACS) or Non-ACS was adjudicated by two cardiologists independently.
RESULTS: The hs-cTnI assay showed a lower (10-fold) critical outlier rate (0.091%) and more detectable results above the limit of detection (LOD) (23.4%) and 99th percentile (2.4%), compared to cTnI. Analytical concordance between the two assays was high (94.5%) but decreased (91.7%) when gender-specific hs-cTnI cut-offs were used. The hs-cTnI assay gave fewer false negatives (up to 1.0%) but disproportionately more false positives (up to 6.7%) overall, which improved (3.9%) for serial measurements.
CONCLUSIONS: Laboratories should analytically and clinically verify hs-cTn assays before use, with attention to performance and the clinical and diagnostic algorithms that support appropriate testing and result interpretation. Work in the pre- and post-analytical phases is necessary to augment the analytical improvement in the new era of troponin testing.