Heart-type fatty acid binding protein as an early marker for myocardial infarction: systematic review and meta-analysis

Background Heart-type fatty acid binding protein (H-FABP) has been proposed as an early biomarker of myocardial infarction (MI). The authors aimed to undertake a systematic review and meta-analysis to estimate the early sensitivity and specificity of quantitative and qualitative H-FABP assays. Methods The authors undertook a systematic search using electronic databases, citation lists and expert contacts to identify all diagnostic cohort studies of patients presenting with suspected acute coronary syndrome that compared H-FABP at presentation to a reference standard based on the Universal definition of MI. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool. Meta-analysis was conducted using Bayesian Markov chain Monte Carlo simulation. Results The authors included eight studies of quantitative H-FABP and nine studies of qualitative H-FABP. The summary estimates of sensitivity and specificity were 81% (95% prediction interval 50% to 95%) and 80% (26% to 98%) respectively for the quantitative assays and 68% (11% to 97%) and 92% (20% to 100%) respectively for the qualitative assays. Four studies reported the sensitivity of troponin and H-FABP at presentation in which the combination was considered positive if either test was positive. The addition of H-FABP to troponin increased sensitivity from 42-75% to 76-97% but decreased specificity from 94-100% to 65-93%. Conclusion H-FABP has modest sensitivity and specificity for MI at presentation but estimates are subject to substantial uncertainty and primary data are subject to substantial heterogeneity. H-FABP may have a role alongside troponin in improving early sensitivity but comparison with high sensitivity troponin assays is required.