Li Ling, Liu Yuqing, Katrukha Ivan A, Zhang Litao, Shu Xin, Xu Ao, Yang Juan, Wu Yu, Jing Yisha, Wang Hui, Ni Tongxin, Schulz Karen, Bereznikova Anastasia V, Katrukha Alexey G, Apple Fred S, Zhang Yi, Zhang Zhenlu
Clinical Laboratory, Wuhan Asia Heart Hospital, Wuhan, Hubei, China.
Immunoassay Reagent R&D Department, Shenzhen Mindray Bio-Medical Electronics Co., Ltd, Shenzhen, China.
Clin Chem. 2025 Mar 3;71(3):396-405. doi: 10.1093/clinchem/hvae200.
Increased cardiac troponin (cTn) concentrations occur in acute myocardial injury and chronic diseases. Characterization of cTn composition in the circulation may assist in differentiating etiologies of myocardial injury. Our goal was to study cTn composition and kinetics in patients following type 1 myocardial infraction (T1MI), cardiac procedures, and chronic heart diseases to establish the relationship between cTn composition and clinical diagnosis.
Plasma samples were collected from 201 patients with T1MI, 78 undergoing cardiac surgeries, and 218 with chronic cardiomyopathy or chronic heart failure. Major cTn forms in the circulation and their ratios were analyzed using cTn composition immunoassays, targeting (a) the long-cTnT cTnI-cTnT-TnC (ITC) ternary complex, short-cTnT ITC complex cleaved at amino acids residues 189-223 of cTnT, and the binary cTnI-TnC (IC) complex, and designated the "high-sensitivity (hs)-cTnI assay;" (b) the long-cTnT ITC complex, and designated the "long-cTnT ITC complex assay;" (c) the long-cTnT ITC complex and short-cTnT ITC complex, and designated the "hs-total ITC complex assay;" and (d) the central part of cTnT of both the long-cTnT ITC complex and free cTnT, and designated the "hs-cTnT assay."
Early-stage T1MI patients showed a high ratio of long-cTnT ITC complex to cTnI (long-cTnT ITC complex/cTnI, R1). Similarly, patients after acute cardiac surgery exhibited increased cTn concentrations with high R1, which decreased rapidly. In chronic disease, cTn composition exhibited stable and low R1 and high ratios of cTnT to cTnI (cTnT/cTnI, R3).
Kinetic differences in multiple cTn forms contribute to the differentiation between acute injury and chronic disease, with a high proportion of long-cTnT ITC complex implying occurrence of acute injury.
急性心肌损伤和慢性疾病时心肌肌钙蛋白（cTn）浓度会升高。对循环中cTn成分的特征分析可能有助于区分心肌损伤的病因。我们的目标是研究1型心肌梗死（T1MI）、心脏手术及慢性心脏病患者的cTn成分和动力学，以建立cTn成分与临床诊断之间的关系。
收集了201例T1MI患者、78例接受心脏手术患者以及218例慢性心肌病或慢性心力衰竭患者的血浆样本。使用cTn成分免疫分析法分析循环中的主要cTn形式及其比例，该分析法针对（a）长链cTnT的cTnI-cTnT-TnC（ITC）三元复合物、在cTnT氨基酸残基189 - 223处裂解的短链cTnT ITC复合物以及二元cTnI-TnC（IC）复合物，并命名为“高敏（hs）-cTnI检测法”；（b）长链cTnT ITC复合物，并命名为“长链cTnT ITC复合物检测法”；（c）长链cTnT ITC复合物和短链cTnT ITC复合物，并命名为“hs-总ITC复合物检测法”；（d）长链cTnT ITC复合物和游离cTnT的cTnT中心部分，并命名为“hs-cTnT检测法”。
早期T1MI患者显示长链cTnT ITC复合物与cTnI的比例较高（长链cTnT ITC复合物/cTnI，R1）。同样，急性心脏手术后的患者cTn浓度升高且R1较高，但迅速下降。在慢性疾病中，cTn成分表现出稳定且较低的R1以及较高的cTnT与cTnI比例（cTnT/cTnI，R3）。
多种cTn形式的动力学差异有助于区分急性损伤和慢性疾病，长链cTnT ITC复合物比例高意味着急性损伤的发生。
