The predictive value of heart-type fatty acid-binding protein is independent from symptom duration in normotensive patients with pulmonary embolism

Heart-type fatty acid-binding protein: an overlooked cardiac biomarker

Cardiac troponins (cTn) are currently the standard of care for the diagnosis of acute coronary syndromes (ACS) in patients presenting to the emergency department (ED) with chest pain (CP). However, their plasma kinetics necessitate a prolonged ED stay or overnight hospital admission, especially in those presenting early after CP onset. Moreover, ruling out ACS in low-risk patients requires prolonged ED observation or overnight hospital admission to allow serial measurements of c-Tn, adding cost. Heart-type fatty acid-binding protein (H-FABP) is a novel marker of myocardial injury with putative advantages over cTn. Being present in abundance in the myocellular cytoplasm, it is released rapidly (<1 h) after the onset of myocardial injury and could potentially play an important role in both earlier diagnosis of high-risk patients presenting early after CP onset, as well as in risk-stratifying low-risk patients rapidly. Like cTn, H-FABP also has a potential role as a prognostic marker in other conditions where the myocardial injury occurs, such as acute congestive heart failure (CHF) and acute pulmonary embolism (PE). This review provides an overview of the evidence examining the role of H-FABP in early diagnosis and risk stratification of patients with CP and in non-ACS conditions associated with myocardial injury. Key messages Heart-type fatty acid-binding protein is a biomarker that is elevated early in myocardial injury The routine use in the emergency department complements the use of troponins in ruling out acute coronary syndromes in patients presenting early with chest pain It also is useful in risk stratifying patients with other conditions such as heart failure and acute pulmonary embolism.

The new bedside ROCky score to predict the complications in patients with intermediate-risk pulmonary embolism

OBJECTIVE

Pulmonary embolism (PE) remains one of the leading causes of mortality among cardiovascular diseases. We aimed at investigating risk factors of PE complications in patients with intermediate risk and integrate them into a simple model for its' bedside prediction.

METHODS

Among 173 patients with PE, 136 were classified as high or intermediate risk. Patients were retrospectively divided into groups of complicated (n = 44) or uncomplicated (n = 92) course. Study endpoints: obstructive shock, recurrent PE, needs for resuscitation/thrombolysis/hemodynamic support and death during 30 days.

RESULTS

Predictors of PE complications were: chronic heart failure, diabetes mellitus (DM), atrial fibrillation, permanent risk factor of venous thromboembolism, syncope, positive heart-type fatty acid binding protein (hFABP), positive troponin I, heart rate (HR) ≥ 110 bpm, systolic blood pressure (SBP) ≤ 100 mmHg, creatinine clearance ≤ 70 ml/min. Multivariate logistic regression analysis was used to model a simple predictive score named ROCky (Risk of Complications): HR ≥ 110 bpm (1.5 points), SBP ≤ 100 mmHg (2.5 points), positive hFABP (2 points) and presence of DM (2.5 points). The AUROC of this model was 0.89 to predict any complication, 0.83 for obstructive shock and 0.92 for death from any cause; the optimal cut-off scores for any complication was ≥2.5 points, ≥3.5 for obstructive shock and ≥4.5 points for death within 30 days.

CONCLUSION

hFABP, tachycardia, hypotension and DM were identified as the major independent determinants of complications development in patients with pulmonary embolism and may be used in combination as the bedside simple predictive ROCky score for early risk stratification in intermediate-risk group.

Prognostic models in acute pulmonary embolism: a systematic review and meta-analysis

OBJECTIVE

To review the evidence for existing prognostic models in acute pulmonary embolism (PE) and determine how valid and useful they are for predicting patient outcomes.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

OVID MEDLINE and EMBASE, and The Cochrane Library from inception to July 2014, and sources of grey literature.

ELIGIBILITY CRITERIA

Studies aiming at constructing, validating, updating or studying the impact of prognostic models to predict all-cause death, PE-related death or venous thromboembolic events up to a 3-month follow-up in patients with an acute symptomatic PE.

DATA EXTRACTION

Study characteristics and study quality using prognostic criteria. Studies were selected and data extracted by 2 reviewers.

DATA ANALYSIS

Summary estimates (95% CI) for proportion of risk groups and event rates within risk groups, and accuracy.

RESULTS

We included 71 studies (44,298 patients). Among them, 17 were model construction studies specific to PE prognosis. The most validated models were the PE Severity Index (PESI) and its simplified version (sPESI). The overall 30-day mortality rate was 2.3% (1.7% to 2.9%) in the low-risk group and 11.4% (9.9% to 13.1%) in the high-risk group for PESI (9 studies), and 1.5% (0.9% to 2.5%) in the low-risk group and 10.7% (8.8% to12.9%) in the high-risk group for sPESI (11 studies). PESI has proved clinically useful in an impact study. Shifting the cut-off or using novel and updated models specifically developed for normotensive PE improves the ability for identifying patients at lower risk for early death or adverse outcome (0.5-1%) and those at higher risk (up to 20-29% of event rate).

CONCLUSIONS

We provide evidence-based information about the validity and utility of the existing prognostic models in acute PE that may be helpful for identifying patients at low risk. Novel models seem attractive for the high-risk normotensive PE but need to be externally validated then be assessed in impact studies.

Acute phase treatment of venous thromboembolism: advanced therapy. Systemic fibrinolysis and pharmacomechanical therapy

Venous thromboembolism, which encompasses deep-vein thrombosis and acute pulmonary embolism (PE), represents a major contributor to global disease burden worldwide. For patients who present with cardiogenic shock or persistent hypotension (acute high-risk PE), there is consensus that immediate reperfusion treatment applying systemic fibrinolysis or, in the case of a high bleeding risk, surgical or catheter-directed techniques, is indicated. On the other hand, for the large, heterogeneous group of patients presenting without overt haemodynamic instability, the indications for advanced therapy are less clear. The recently updated guidelines of the European Society of Cardiology emphasise the importance of clinical prediction rules in combination with imaging procedures (assessment of right ventricular function) and laboratory biomarkers (indicative of myocardial stress or injury) for distinguishing between an intermediate and a low risk for an adverse early outcome. In intermediate-high-risk PE defined by the presence of both right ventricular dysfunction on echocardiography (or computed tomography) and a positive troponin (or natriuretic peptide) test, the bleeding risks of full-dose fibrinolytic treatment have been shown to outweigh its potential clinical benefits unless clinical signs of haemodynamic decompensation appear (rescue fibrinolysis). Recently published trials suggest that catheter-directed, ultrasound-assisted, low-dose local fibrinolysis may provide an effective and particularly safe treatment option for some of these patients.

Predictive value of the heart-type fatty acid-binding protein and the Pulmonary Embolism Severity Index in patients with acute pulmonary embolism in the emergency department

OBJECTIVES

Heart-type fatty acid-binding protein (h-FABP), sensitive troponins, natriuretic peptides, and clinical scores such as the Pulmonary Embolism Severity Index (PESI) are candidates for risk stratification of patients with acute pulmonary embolism (PE). The aim was to compare their respective prognostic values to predict an adverse outcome at 1 month.

METHODS

The authors prospectively included 132 consecutive patients with confirmed acute PE. On admission to the emergency department (ED), plasma concentrations of h-FABP, sensitive cardiac troponin I-Ultra (cTnI-Ultra), and brain natriuretic peptide (BNP) were measured and the PESI calculated in all patients. The combined 30-day outcomes of interest were death, cardiac arrest, mechanical ventilation, use of catecholamines, and recurrence of acute PE.

RESULTS

During the first 30 days, 14 (10.6%) patients suffered complications. Among the biomarkers, h-FABP above 6 μg/L was a stronger predictor of an unfavorable outcome (odds ratio [OR] = 17.5, 95% confidence interval [CI] = 4.2 to 73.3) than BNP > 100 pg/mL (OR = 5.7, 95% CI = 1.6 to 20.4) or cTnI-Ultra > 0.05 μg/L (OR = 3.4, 95% CI = 1.1 to 10.9). The PESI classified 83 of 118 patients (70.3%) with favorable outcomes and only one of 14 (7%) with adverse outcomes in low class I or II (OR = 30.8, 95% CI = 3.2 to 299.7). The areas under the receiver operating characteristic (ROC) curves (AUCs) were 0.90 (95% CI = 0.81 to 0.98) for h-FABP, 0.89 (95% CI = 0.82 to 0.96) for PESI, 0.79 (95% CI = 0.67 to 0.90) for BNP, and 0.76 (95% CI = 0.64 to 0.87) for cTnI-Ultra. The combination of h-FABP with PESI was a particularly useful prognostic indicator because none of the 79 patients (59.8%) with h-FABP < 6 ng/mL and PESI class < III had an adverse outcome.

CONCLUSIONS

h-FABP and the PESI are superior to BNP and cTnI-Ultra as markers for risk stratification of patients with acute PE. The high sensitivity of their combination identified a large number of low-risk patients in the ED.