Evaluation of the diagnostic performance of heart-type fatty acid binding protein in the BWH-TIMI ED chest pain study

Promising Novel Biomarkers in Cardiovascular Diseases

Cardiovascular diseases remain the most common causes of death globally, according to the World Health Organization. In recent years, a great number of biomarkers have been investigated, whereas only some have gained value in the diagnosis, prognosis, and risk stratification of different cardiovascular illnesses. As numerous studies have investigated the diagnostic yield of novel biomarkers in various disease entities every year, this review aims to provide an overview of the current status of four promising representatives. In particular, this manuscript refers to soluble suppression of tumorigenicity 2 (sST2), heart-type fatty acid binding protein (H-FABP), growth differentiation factor (GDF-15) and soluble urokinase-type plasminogen activator receptor (suPAR). These markers are of special interest as they are thought to provide an accurate estimate of cardiovascular risk in certain patient populations, especially those with pre-existing diseases, such as obesity or diabetes mellitus. We sought to give an overview of their function, individual diagnostic and predictive value and determination in the laboratory. A review of the literature regarding the aforementioned cardiovascular biomarkers yielded manifold results with respect to their individual diagnostic and prognostic value. Yet, the clinical relevance of these findings remains unclear, warranting further studies to identify their optimal use in clinical routine.

Heart-Type Fatty Acid-Binding Protein (H-FABP) and its Role as a Biomarker in Heart Failure: What Do We Know So Far?

BACKGROUND

Heart failure (HF) remains one of the leading causes of death to date despite extensive research funding. Various studies are conducted every year in an attempt to improve diagnostic accuracy and therapy monitoring. The small cytoplasmic heart-type fatty acid-binding protein (H-FABP) has been studied in a variety of disease entities. Here, we provide a review of the available literature on H-FABP and its possible applications in HF. Methods: Literature research using PubMed Central was conducted. To select possible studies for inclusion, the authors screened all available studies by title and, if suitable, by abstract. Relevant manuscripts were read in full text.

RESULTS

In total, 23 studies regarding H-FABP in HF were included in this review.

CONCLUSION

While, algorithms already exist in the area of risk stratification for acute pulmonary embolism, there is still no consensus for the routine use of H-FABP in daily clinical practice in HF. At present, the strongest evidence exists for risk evaluation of adverse cardiac events. Other future applications of H-FABP may include early detection of ischemia, worsening of renal failure, and long-term treatment planning.

Evaluating possible acute coronary syndrome in primary care: the value of signs, symptoms, and plasma heart-type fatty acid-binding protein (H-FABP). A diagnostic study

Background

Additional diagnostic means could be of added value when evaluating possible acute coronary syndrome (ACS) in primary care.

Aim

To determine whether heart-type fatty acid-binding protein (H-FABP)-based point-of-care (POC) biomarker testing, embedded in a clinical decision rule (CDR), is helpful to the GP when evaluating possible ACS.

Design & setting

A prospective, non-randomised, double-blinded, diagnostic derivation study was undertaken, with a delayed-type cross-sectional diagnostic model among GPs in the Netherlands and Belgium.

Method

Signs and symptoms predicting acute myocardial infarction (AMI) or ACS were identified using both logistic regression analysis, and classification and regression trees (CART). Diagnostic values of the POC H-FABP test (cut-off value 4 ng/ml) alone and as part of a CDR were determined.

Results

A total of 303 participants (48.8% male) with chest pain or discomfort who had consulted a GP were enrolled. ACS was found in 32 (10.6%) of these 303 patients. For ACS, sensitivity and negative predictive value (NPV) of the POC H-FABP test was 25.8% (95% confidence interval [CI] = 12.5 to 44.9) and 91.6% (95% CI = 87.6% to 94.5%), respectively. The area under the receiver operating curve of the optimal CDR was 0.78 for ACS.

Conclusion

Sensitivity of the current H-FABP POC test (cut-off value 4 ng/ml) as a stand-alone test is poor, either owing to limitations of the marker or of the test device. Usability of a CDR derived from these results is doubtful: the number of ACS cases missed by the GP is reduced but, as a consequence, disproportionally more ACS-negative patients are referred.

Early Diagnostic Performance of Heart-Type Fatty Acid Binding Protein in Suspected Acute Myocardial Infarction: Evidence From a Meta-Analysis of Contemporary Studies

BACKGROUND

Although cardiac troponin is the cornerstone in diagnosis of acute myocardial infarction (AMI), the accuracy is still suboptimal in the early hours after chest pain onset. Due to its small size, heart-type fatty acid-binding protein (H-FABP) has been reported accurate in diagnosis of AMI, however, this remains undetermined. The aim is to investigate the diagnostic performance of H-FABP alone and in conjunction with high-sensitivity troponin (hs-Tn) within 6 hours of symptom onset. Furthermore, accuracy in 0h/3h algorithm was also assessed.

METHODS

Medline and EMBASE databases were searched; sensitivity, specificity and area under ROC curve (AUC) were used as measures of the diagnostic accuracy. We pooled data on bivariate modelling, threshold effect and publication bias was applied for heterogeneity analysis.

RESULTS

Twenty-two studies with 6602 populations were included, pooled sensitivity, specificity and AUC of H-FABP were 0.75 (0.68-0.81), 0.81 (0.75-0.86) and 0.85 (0.82-0.88) within 6 hours. Similar sensitivity (0.76, 0.69-0.82), specificity (0.80, 0.71-0.87) and AUC (0.85, 0.82-0.88) of H-FABP were observed in 4185 (63%) patients in 0h/3h algorithm. The additional use of H-FABP improved the sensitivity of hs-Tn alone but worsened its specificity (all p<0.001), and resulted in no improvement of AUC (p>0.99). There was no threshold effect (p=0.18) and publication bias (p=0.31) in this study.

CONCLUSIONS

H-FABP has modest accuracy for early diagnosis of AMI within 3 and 6 hours of symptom onset. The incremental value of H-FABP seemed much smaller and was of uncertain clinical significance in addition to hs-Tn in patients with suspected AMI. Routine use of H-FABP in early presentation does not seem warranted.

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.

Rapidly rule out acute myocardial infarction by combining copeptin and heart-type fatty acid-binding protein with cardiac troponin

Background

The rapid exclusion of acute myocardial infarction in patients with chest pain can reduce the length of hospital admission, prevent unnecessary diagnostic work-up and reduce the burden on our health-care systems. The combined use of biomarkers that are associated with different pathophysiological aspects of acute myocardial infarction could improve the early diagnostic assessment of patients presenting with chest pain.

Methods

We measured cardiac troponin I, copeptin and heart-type fatty acid-binding protein concentrations in 584 patients who presented to the emergency department with acute chest pain. The diagnostic performances for the diagnosis of acute myocardial infarction and NSTEMI were calculated for the individual markers and their combinations. Separate calculations were made for patients presenting to the emergency department <3 h, 3–6 h and 6–12 h after chest pain onset.

Results

For ruling out acute myocardial infarction, the net predictive values (95% CI) of cardiac troponin I, copeptin and heart-type fatty acid-binding protein were 90.4% (87.3–92.9), 84% (79.8–87.6) and 87% (83.5–90), respectively. Combining the three biomarkers resulted in a net predictive value of 95.8% (92.8–97.8). The improvement was most pronounced in the early presenters (<3 h) where the combined net predictive value was 92.9% (87.3–96.5) compared to 84.6% (79.4–88.9) for cardiac troponin I alone. The area under the receiver operating characteristic for the triple biomarker combination increased significantly ( P < 0.05) compared to that of cardiac troponin I alone (0.880 [0.833–0.928] vs. 0.840 [0.781–0.898], respectively).

Conclusions

Combining copeptin, heart-type fatty acid-binding protein and cardiac troponin I measurements improves the diagnostic performance in patients presenting with chest pain. Importantly, in patients who present early (<3 h) after chest pain onset, the combination improves the diagnostic performance compared to the standard cardiac troponin I measurement alone.

Incremental value of heart-type fatty acid-binding protein in suspected acute myocardial infarction early after symptom onset

BACKGROUND

The early diagnosis of acute myocardial infarction (AMI) very soon after symptom onset remains a major clinical challenge, even when using high-sensitivity cardiac troponin (hs-cTnT).

METHODS AND RESULTS

We investigated the incremental value of heart-type fatty acid-binding protein (hFABP) in a pre-specified subgroup analysis of patients presenting with suspected AMI within 1 h of symptom onset to the emergency department (ED) in a multicentre study. HFABP was measured in a blinded fashion. Two independent cardiologists using all available clinical information, including hs-cTnT, adjudicated the final diagnosis. Overall, 1411 patients were enrolled, of whom 105 patients presented within 1 h of symptom onset. Of these, 34 patients (32.4%) had AMI. The diagnostic accuracy as quantified by the area under the receiver-operating characteristics curve (AUC) of hFABP was high (0.84 (95% CI 0.74-0.94)). However, the additional use of hFABP only marginally increased the diagnostic accuracy of hs-cTnT (AUC 0.88 (95% CI 0.81-0.94) for hs-cTnT alone to 0.90 (95% CI 0.83-0.98) for the combination; p=ns). After the exclusion of 18 AMI patients with ST-segment elevation, similar results were obtained. Among the 16 AMI patients without ST-segment elevation, six had normal hs-cTnT at presentation. Of these, hFABP was elevated in two (33.3%) patients.

CONCLUSIONS

hFABP does not seem to significantly improve the early diagnostic accuracy of hs-cTnT in the important subgroup of patients with suspected AMI presenting to the ED very early after symptom onset.

Point-of-care heart-type fatty acid binding protein versus high-sensitivity troponin T testing in emergency patients at high risk for acute coronary syndrome

BACKGROUND

High-sensitivity cardiac troponin testing is used to detect myocardial damage in patients with acute chest pain. Heart-type fatty acid binding protein (H-FABP) may be an alternative, available as point-of-care test.

METHODS

Patients (n=203) referred by general practitioners for suspected acute coronary syndrome or presenting with typical chest pain and one major cardiovascular risk factor at the emergency department were prospectively included in a single-centre cohort study. High-sensitivity cardiac troponin T (hs-TnT) and point-of-care H-FABP testing were concomitantly performed at admission and after 6h.

RESULTS

Maximal hs-TnT levels above the 99th percentile were observed in 152 patients (75%) with 127 (63%) fulfilling criteria for myocardial infarction. Upon admission, hs-TnT and H-FABP were associated with an area under the curve (95% CI) of 0.83 (0.77-0.89) and 0.79 (0.73-0.85), respectively, to predict myocardial infarction, which increased to 0.93 (0.90-0.97) and 0.88 (0.84-0.93), respectively, after 6h. The diagnostic accuracy for non-ST-segment elevation myocardial infarction was somewhat lower with an area under the curve (95% CI) of 0.80 (0.72-0.87), 0.90 (0.84-0.96), 0.73 (0.64-0.81) and 0.77 (0.67-0.86), respectively. When assessment was performed within 3h of chest pain onset, diagnostic accuracy of H-FABP versus hs-TnT was similar. Each standard deviation increase in admission H-FABP was associated with a 68% relative risk increase of all-cause mortality (p-value=0.027) during 666 ± 155 days of follow-up.

CONCLUSIONS

Point-of-care H-FABP testing has lower diagnostic accuracy compared with hs-TnT assessment in patients with high pre-test acute coronary syndrome probability, but might be of interest when assessment is possible early after chest pain onset.

Utility of Heart-type Fatty Acid Binding Protein as a New Biochemical Marker for the Early Diagnosis of Acute Coronary Syndrome

INTRODUCTION

Acute coronary syndrome (ACS) refers to a constellation of clinical symptoms caused by acute myocardial ischemia. Cardiovascular diseases (CVDs) are major and growing contributors to mortality and disability in India.

AIMS AND OBJECTIVES

Especially patients with non-ACS-related troponin elevations have an adverse outcome and require careful patient management. So, we look forward for another marker Heart-type Fatty Acid Binding Protein (H-FABP) that reliably detects myocardial ischemia in the absence of necrosis and would be useful for initial identification and for differentiating patients with chest pain of aetiology other than coronary ischemia.

MATERIALS AND METHODS

The study was done on 88 subjects of whom 34 subjects were with ischemic chest pain, 29 were with non-ischemic chest pain and 25 were normal subjects.

RESULTS

Receiver operating characteristic (ROC) curve analysis was done which showed that area under the curve (AUC) for H-FABP was 0.885(0.79-0.94) and that of high-sensitive Troponin T (hs-TnT) in initial six hours was 0.805(0.70-0.88). The specificity of H-FABP was higher compare to hs-TnT while sensitivity was comparable during 0-6 h of presentation of chest pain.

CONCLUSION

H-FABP can be used as an additional marker to hs-TnT in diagnosis of myocardial infarction (MI) and for exclusion of non-AMI (acute myocardial infarction) patients.

The value of signs, symptoms and plasma heart-type fatty acid-binding protein (H-FABP) in evaluating patients presenting with symptoms possibly matching acute coronary syndrome: background and methods of a diagnostic study in primary care

Background

Chest complaints presented to a general practitioner (GP) are frequently caused by diseases which have advantageous outcomes. However, in some cases, acute coronary syndrome (ACS) is present (1.5-22% of cases). The patient’s signs, symptoms and electrocardiography results are insufficient diagnostic tools to distinguish mild disease from ACS. Therefore, most patients presenting chest complaints are referred to secondary care facilities where ACS is then ruled out in a majority of patients (78%). Recently, a point of care test for heart-type fatty acid-binding protein (H-FABP) using a low cut-off value between positive and negative of 4 ng/ml has become available. We aim to study the role of this point of care device in triage of patients presenting chest complaints possibly due to ACS, in primary care. Our research protocol is presented in this article. Results are expected in 2015.

Methods/Design

Participating GPs will register signs and symptoms in all patients presenting chest complaints possibly due to ACS. Point of care H-FABP testing will also be performed. Our study will be a derivation study to identify signs and symptoms that, combined with point of care H-FABP testing, can be part of an algorithm to either confirm or rule out ACS. The diagnostic value for ACS of this algorithm in general practice will be determined.

Discussion

A safe diagnostic elimination of ACS by application of the algorithm can be of significant clinical relevance. Improved triage and thus reduction of the number of patients with chest complaints without underlying ACS, that are referred to secondary care facilities, could lead to a substantial cost reduction.

Trial registration

ClinicalTrials.gov, NCT01826994, accepted April 8^th 2013.

Heart-type fatty acid binding protein in early diagnosis of myocardial infarction in the era of high-sensitivity troponin: a systematic review and meta-analysis

Introduction

Heart-type fatty acid binding protein (HT FABP) is an emerging biomarker of ischaemic myocardial necrosis. While previous studies have demonstrated its additive value when compared to contemporary troponin assays in the diagnosis of acute myocardial infarction (AMI), its utility in the era of high-sensitivity troponin (hsTn) assays remains undetermined.

Methodology

A systematic review and meta-analysis of relevant studies was performed comparing the diagnostic performance of HT FABP both alone and in conjunction with hsTn in the early diagnosis and exclusion of AMI.

Results

A systematic literature search yielded eight eligible studies including 3395 patients. Of these, 716 patients (21.1%) were eventually diagnosed with AMI. The pooled sensitivity and specificity for hsTn on admission was 82.5% (95% confidence interval [CI]: 79.8–85.0%) and 89.7% (95% CI: 88.7–90.6%), respectively, while the area under the curve (AUC) for the summary receiver operating characteristics (ROC) curve is 0.92 (SE 0.02). While the pooled specificity (84.6%, 95% CI: 83.2–85.9%) of admission HT FABP is similar to hsTn for the early diagnosis of AMI ( P = 0.07), its pooled sensitivity (63.5%, 95% CI: 59.9–67.1%, P < 0.001) is significantly worse. Accordingly, the AUC of the summary ROC curve for HT FABP (0.79, SE 0.03) is inferior to hsTn ( P < 0.0001). The addition of HT FABP to hsTn resulted in no improvement in the sensitivity ( P = 0.058) and worsened the specificity ( P = 0.001) in the early diagnosis of AMI compared to hsTn alone.

Conclusion

HT FABP does not appear to improve the diagnostic accuracy of hsTn, and consequently its routine use currently cannot not be recommended.

Overview of cardiac markers in heart disease

Cardiac troponins I and T have been the cornerstone of diagnostics of acute coronary syndrome for almost 20 years. Natriuretic peptides have established themselves in heart failure during the last decade. These and additional promising biomarkers, such as ST-2, galectin-3, GDF-15, copeptin, midregional proadrenomedullin, and the markers of glomerular filtration rate and kidney injury, are reviewed in groups corresponding to the pathophysiological processes they probe--cardiomyocyte injury, myocyte stress, inflammation, oxidative stress, plaque instability, extracellular-matrix remodeling, or those markers grouped in the neurohormone category. Biomarkers linking the renal and cardiac functions and microRNAs and metabolomic markers are addressed as well.