Consistency analysis of high-sensitivity cardiac troponin I in peripheral blood and venous blood by quantum dot immunofluorescence assay and clinical application in acute myocardial infarction

BACKGROUND: Troponin is an important marker for the diagnosis of acute myocardial infarction (AMI). The detection of troponin in peripheral blood is simpler and more convenient than that in venous blood, which has attracted more and more clinical attention. The purpose of this study is to establish a novel method for the rapid detection of high-sensitivity troponin I (hs-cTnI) in peripheral blood by quantum dot fluorescence immunoassay and evaluated the clinical accuracy of the method. METHODS: A total of 90 patients with chest pain admitted to Wuxi Second People’s Hospital of Nanjing Medical University had peripheral blood and venous blood samples collected for detection of hs-cTnI by rapid quantum dot fluorescence immunoassay. The differences between the two methods were evaluated, as well as the analytical performance and clinical diagnostic efficacy of hs-cTnI detection by quantum dot fluorescence immunoassay. The final diagnosis was determined by two independent cardiologists. RESULTS: This study verified the precision, linear range and sensitivity of the novel detection method. There was good correlation between the results of hs-cTnI quantum dot fluorescence immunoassay for peripheral blood and the results for venous blood (regression equation Y=1.026x+0.521, R(2)=0.9337); 94.4% (85/90) of the data were within the conformance limit. In addition, in the analysis of 52 patients with confirmed AMI, the clinical specificity of the quantum dot fluorescence immunoassay in peripheral blood was the same as that in venous blood samples (89.5%:89.5%). Finally, the area under the receiver operating characteristic (ROC) curve of the peripheral blood quantum dot fluorescence immunoassay was 0.9352, the 95% confidence interval (CI) was 0.8829 to 0.9876, the cut-off value was 1.598, and the sensitivity was 82.69%, which was not significantly different from the venous blood method (P value =0.089). CONCLUSIONS: Rapid detection of hs-cTnI by quantum dot fluorescence immunoassay in peripheral blood is feasible. It has a high correlation and consistency with the venous blood method, as well as a high clinical diagnostic value for AMI and is more convenient and easier to detect.