Suspected acute coronary syndrome in the emergency room: Limited added value of heart type fatty acid binding protein point of care or ELISA tests: The FAME-ER (Fatty Acid binding protein in Myocardial infarction Evaluation in the Emergency Room) study.

BACKGROUND: Timely recognition of acute coronary syndrome remains a challenge as many biomarkers, including troponin, remain negative in the first hours following the onset of chest pain. We assessed the diagnostic accuracy of heart-type fatty acid binding protein (H-FABP), a cardiac biomarker with potential value immediately post symptom onset. METHODS AND RESULTS: Prospective monocentre diagnostic accuracy study of H-FABP bedside point of care (CardioDetect®) and ELISA tests in acute coronary syndrome suspected patients presenting within 24 hours of symptom onset to the emergency department, in addition to clinical findings, electrocardiography and the currently recommended biomarker high sensitivity troponin-T (hs-cTnT). The final diagnosis of acute coronary syndrome was adjudicated by two independent cardiologists, blinded to H-FABP results. Acute coronary syndrome was diagnosed in 149 (32.9%) of 453 unselected patients with suspected acute coronary syndrome (56% men, mean age 62.6 years). Negative predictive values were similar for H-FABP point of care and ELISA tests (79% vs. 78% respectively), but inferior to initial hs-cTnT (negative predictive value 86%). The addition of H-FABP point of care results to hs-cTnT increased the negative predictive value to 89%. In a multivariable logistic regression model, H-FABP point of care and ELISA tests yielded relevant diagnostic information in addition to clinical findings and ECG (likelihood ratio test p<0.001) and increased area under the receiver operating characteristics curve (AUC; 0.82 vs. 0.84 and 0.84). This added value attenuated, however, after inclusion of hs-cTnT in the diagnostic model (AUC 0.88). CONCLUSIONS: In patients suspected of acute coronary syndrome presenting to the emergency department, H-FABP testing improves diagnostic accuracy in addition to clinical findings and electrocardiography. H-FABP, however, has no additional diagnostic value when hs-cTnT measurements are also available.

No Added Value of Novel Biomarkers in the Diagnostic Assessment of Patients Suspected of Acute Coronary Syndrome.

BACKGROUND: Despite the availability of high-sensitive troponin (hs-cTnT), there is still room for improvement in the diagnostic assessment of patients suspected of acute coronary syndrome (ACS). Apart from serial biomarker testing, which is time-consuming, novel biomarkers like copeptin have been proposed to expedite the early diagnosis of suspected ACS in addition to hs-cTnT. We determined whether placenta derived growth factor (PlGF), soluble Fms-like tyrosine kinase 1 (sFlt-1), myoglobin, N-terminal prohormone B-type Natriuretic Peptide (NT-proBNP), growth-differentiation factor 15 (GDF-15) and copeptin improved early assessment of chest pain patients. METHODS: This prospective, single centre diagnostic FAME-ER study included patients presenting to the ED with symptoms suggestive of ACS. Blood was collected to measure biomarkers, notably, hs-cTnT was retrospectively assessed. Added value of markers was judged by increase in AUC using multivariable logistic regression. RESULTS: Of 453 patients enrolled, 149 (33%) received a final diagnosis of ACS. Hs-cTnT had the highest diagnostic value in both univariable and multivariable analysis. PPVs of the biomarkers ranged from 23.5% (PlGF) to 77.9% (hs-cTnT), NPVs from 67.0% (PlGF) to 86.4% (hs-cTnT). Only myoglobin yielded diagnostic value in addition to clinical symptoms and electrocardiography (ECG) (AUC of clinical model 0.80) with AUC of 0.84 (p<0.001). However, addition of hs-cTnT was superior (AUC 0.89, p<0.001). Addition of the biomarkers to our clinical model and hs-cTnT did not or only marginally (GDF-15) improved diagnostic performance. CONCLUSION: When assessing patients suspected of ACS, only myoglobin had added diagnostic value beyond clinical symptoms and ECG. However, when combined with hs-cTnT, it yields no additional diagnostic value. PlGF, sFlt-1, NT-proBNP, GDF-15 and copeptin had no added value to the clinical model or hs-cTnT.

Early assessment of acute coronary syndromes in the emergency department: the potential diagnostic value of circulating microRNAs.

Previous studies investigating the role of circulating microRNAs in acute coronary syndrome (ACS) were based on small patient numbers, performed no comparison with established markers of cardiac injury and did not have appropriate controls. We determined the potential diagnostic value of circulating microRNAs as novel early biomarkers in 332 suspected ACS patients on presentation to the emergency department (ED) in a prospective single-centre study including cardiac miRNAs (miR-1, -208a and -499), miR-21 and miR-146a. Levels of all miRs studied were significantly increased in 106 patients diagnosed with ACS, even in patients with initially negative high-sensitive (hs) troponin or symptom onset <3 h. MiR-1, miR-499 and miR-21 significantly increased the diagnostic value in all suspected ACS patients when added to hs-troponin T (AUC 0.90). These three miRs were strong predictors of ACS independent of clinical co-variates including patient history and cardiovascular risk factors. Interestingly, the combination of these three miRs resulted in a significantly higher AUC of 0.94 than hs-troponin T (0.89). Circulating microRNAs hold great potential as novel early biomarkers for the management of suspected ACS patients.

Novel biochemical markers in suspected acute coronary syndrome: systematic review and critical appraisal.

CONTEXT: Early recognition of acute coronary syndrome (ACS) is essential. Cardiac troponins are not consistently elevated within the first hours after symptom onset. OBJECTIVE: Review current guidelines recommendations regarding biomarkers in the early assessment of ACS and review the evidence for using established and specific new diagnostic biomarkers. DATA SOURCES: MEDLINE and EMBASE. STUDY SELECTION: Articles on diagnostic accuracy of ACS biomarkers. DATA EXTRACTION: Relevance of clinical domain, adequacy of measures of clinical utility and outcome assessment. RESULTS: The 73 articles identified on early biochemical markers CK-MB, myoglobin, heart-type fatty acid binding protein (H-FABP), ischemia modified albumin (IMA), pregnancy-associated plasma protein A, glycogen phosphorylase isoenzyme BB and myeloid-related protein 8/14 often did not quantify clinical utility correctly. CONCLUSIONS: IMA and H-FABP seem to be promising biomarkers in the early assessment of ACS. There is an urgent need for adequately designed diagnostic studies of (novel) ACS markers against contemporary troponin assays.