Scirica Benjamin M, Morrow David A
TIMI Study Group, Cardiovascular Division, Department of Medicine, Brigham & Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
Prog Cardiovasc Dis. 2004 Nov-Dec;47(3):177-88. doi: 10.1016/j.pcad.2004.07.004.
Cardiac troponins have replaced creatine kinase-MB as the preferred biomarker for establishing the diagnosis of myocardial infarction (MI). Expert recommendations set the diagnostic decision-limit for each assay at the 99th percentile of troponin levels in an apparently healthy reference population, which due to a lack of standardization, will vary depending upon the manufacturer. Among patients presenting with an acute coronary syndrome (ACS), even low-level elevations of cardiac troponin T or I correlate with higher risk of death and recurrent ischemic events compared to patients with levels of troponin below the decision limit. Renal failure does not appear to diminish the prognostic value of troponins among patients with a high clinical probability of ACS. Moreover, patients with elevated levels of troponin derive the most benefit from more intense medical therapy with antithrombin and antiplatelet medications, as well as an early invasive management strategy. Whereas cardiac troponins are extremely specific for myocardial necrosis, they do not discriminate between ischemic and non-ischemic etiologies of myocardial injury. Clinicians must, therefore, determine whether a patient's presenting symptoms are consistent with ACS. Combining troponin with other cardiac biomarkers may offer complimentary information on the underlying pathobiology and prognosis in an individual patient. Future generations of troponin assays may detect specific posttranslational modifications of troponins that may increase the analytic sensitivity for myocardial damage and offer insight into the timing and mechanism of myocardial injury.
心肌肌钙蛋白已取代肌酸激酶同工酶MB，成为诊断心肌梗死（MI）的首选生物标志物。专家建议将每种检测方法的诊断决定限设定为明显健康的参考人群中肌钙蛋白水平的第99百分位数，由于缺乏标准化，该数值会因制造商而异。在急性冠状动脉综合征（ACS）患者中，与肌钙蛋白水平低于决定限的患者相比，即使心肌肌钙蛋白T或I的低水平升高也与更高的死亡风险和复发性缺血事件相关。肾衰竭似乎并未降低肌钙蛋白在临床高度怀疑ACS患者中的预后价值。此外，肌钙蛋白水平升高的患者从更强化的抗凝血酶和抗血小板药物治疗以及早期侵入性管理策略中获益最大。虽然心肌肌钙蛋白对心肌坏死具有极高的特异性，但它们无法区分心肌损伤的缺血性和非缺血性病因。因此，临床医生必须确定患者的症状是否与ACS相符。将肌钙蛋白与其他心脏生物标志物结合使用，可能会为个体患者的潜在病理生物学和预后提供补充信息。未来的肌钙蛋白检测方法可能会检测到肌钙蛋白的特定翻译后修饰，这可能会提高对心肌损伤的分析敏感性，并深入了解心肌损伤的时间和机制。
