Diagnostic significance of plasma troponin and cardiomyocyte fatty acid-binding protein levels in acute coronary syndrome

Abstract

Blood serum content of fatty acid-binding (FABP) protein increases within 2-3 h after the onset of acute coronary syndrome and myocardial infarction (MI) and reaches the maximum 8.5 h after the initiation of cardiomyocyte death. FABP content considerably decreases by the end of at 24-h period due to excretion with urine, remaining elevated for subsequent 24 h. High clinical sensitivity and relatively high organ specificity are typical of FABP for 12 h after ACS. Within the early period of MI clinical specificity of FABP prevails over troponin in terms of concentration. Troponins display higher clinical sensitivity and diagnostic specificity during a 12-h period after ACS, prevailing for several days after MI. Simultaneous measuring of FABP and troponins (Tr) within the first 12 h increases the sensitivity of biochemical diagnostics by 30%. At later periods, simultaneous determination of FABP and Tr becomes unnecessary: FABP is excreted with urine and Tr level acquires predominant diagnostic significance. No relationship has been revealed between blood content of FABP and reperfusion according to electrocardiography data, probably due to rare measurements of this highly dynamic parameter. FABP test cannot be used in patients with circulatory disorders since its results are not adequate. The best option for differential diagnostics of ACS within the first 24 h would be a combined express immunochromatographic test which allows to measure blood FABP and Tr levels pending objective evaluation.