Yüksek Duyarlıklı Kardiyak Troponinler ve Toplam Test Süreci
Synopsis
In this chapter published in Current Biochemistry Studies II, Assoc. Prof. Dr. Yeşim Güvenç Demirağcı comprehensively examines high-sensitivity cardiac troponins (hs-cTn), which play a vital role in the diagnosis of cardiovascular diseases and acute myocardial infarction (AMI), along with the total testing process. The study detailedly presents the biochemical structure, genetic foundations, measurement methods, and classification according to analytical sensitivity levels of the troponin complex (cTnI, cTnT, cTnC), which serves a key function in the muscle contraction mechanism. In order to ensure patient safety and generate accurate and reliable results in clinical laboratories, the pre-analytical, analytical, and post-analytical phases constituting the total testing process are analyzed through a holistic approach. In this context, interference factors affecting troponin analyses—such as sample type, coagulation conditions, stability, hemolysis, high-dose biotin intake, heterophile and anti-cTn antibodies, macro-troponin, and non-reproducible outliers—and proposed solutions for them are explained. Furthermore, the standardization of troponin assays, 99th percentile upper reference limit, optimization of analytical quality, ideal turn-around time (TAT ≤ 60 min), measurement units (ng/L), and the critical role of delta (change) monitoring in AMI diagnostic algorithms are emphasized. Finally, the significance of integrating information technology and fostering clinical-laboratory collaboration in improving testing processes is highlighted.
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