Myoglobin stratifies short-term risk in acute major pulmonary embolism

Impact of Promising Biomarkers on Severity and Outcome of Acute Pulmonary Embolism

Background

Acute pulmonary embolism (APE) is a common clinical condition. Its severity ranges from asymptomatic radiological findings to fatal obstructive shock. The potential circulating biomarkers have been studied to predict APE outcomes. This study aimed to explore their predictive power on prognosis in APE.

Material and Method

It was a prospective observational study between March 2008 and April 2010. All consecutive patients diagnosed with APE were categorized as massive/high-risk, submassive/moderate-risk, and non-massive/low-risk. Cardiac troponin T (cTnT), myoglobin, N-terminal pro-brain natriuretic peptide (NT-proBNP), heart-type fatty acid-binding protein (H-FABP), growth differentiation factor-15 (GDF-15), and D-dimer levels were measured.

Results

Of these patients, 14 (29.8%), 16 (34.0%), and 17 (36.2%) patients were categorized as low-risk, moderate-risk, and high risk-patients, respectively. There was no significant difference between the patient groups categorized based on the risk stratification in terms of demographic and clinical characteristics. The cTnT, myoglobin, HFABP, and D-dimer levels have also not differed significantly between the groups. There was a significant difference between the groups in respect of NT-proBNP and GDF-15 levels (p=0.009 and p=0.037, respectively). Nine (19.1%) patients had died by the 3rd-month follow-up. Adverse events were seen in 26 (55.3%) patients. GDF-15 had the highest area under the curve (AUC) value for predicting any adverse event (cut-off value=9.3 ng/mL, AUC=0.796, CI (confidence interval) 95%: 0.653-0.899). NT-ProBNP was determined as the best predictor for mortality (cut-off value=229.2 pg/mL, AUC=0.889, CI 95%: 0.756-0.964).

Conclusion

Higher levels of NT-proBNP and GDF-15 were found to be associated with more severe APE, worse outcomes, and mortality.

Use of machine learning models to predict in-hospital mortality in patients with acute coronary syndrome

BACKGROUND

Cardiovascular diseases are a significant health burden with the prevalence increasing worldwide. Thus, a highly accurate assessment and prediction of death risk are crucial to meet the clinical demand. This study sought to develop and validate a model to predict in-hospital mortality among patients with the acute coronary syndrome (ACS) using nonlinear algorithms.

METHODS

A total of 2414 ACS patients were enrolled in this study. All samples were divided into five groups for cross-validation. The logistic regression (LR) model and XGboost model were applied to predict in-hospital mortality. The results of two models were compared between the variable set by the global registry of acute coronary events (GRACE) score and the selected variable set.

RESULTS

The in-hospital mortality rate was 3.5% in the dataset. Model performance on the selected variable set was better than that on GRACE variables: a 3% increase in area under the receiver operating characteristic (ROC) curve (AUC) for LR and 1.3% for XGBoost. The AUC of XGBoost is 0.913 (95% confidence interval [CI]: 0.910-0.916), demonstrating a better discrimination ability than LR (AUC = 0.904, 95% CI: 0.902-0.905) on the selected variable set. Almost perfect calibration was found in XGBoost (slope of predicted to observed events, 1.08; intercept, -0.103; p < .001).

CONCLUSIONS

XGboost modeling, an advanced machine learning algorithm, identifies new variables and provides high accuracy for the prediction of in-hospital mortality in ACS patients.

Lipocalin-2, S100A8/A9, and cystatin C: Potential predictive biomarkers of cardiovascular complications in COVID-19

Severe coronavirus (SARS-COV-2) infection often leads to systemic inflammation accompanied by cardiovascular complications including venous thromboembolism (VTE). However, it is largely undefined if inflammatory markers such as lipocalin-2 (LNC2), calprotectin (S100A8/A9), and cystatin C (CST3), previously linked with VTE, play roles in cardiovascular complications and advancement of COVID-19 severity. To investigate the same, hospitalized moderate and severe (presented pneumonia and required intensive care) COVID-19 patients were recruited. The levels of plasma LNC2, S100A8/A9, CST3, myoglobin, and cardiac Troponin I (cTnI) were assessed through enzyme-linked immunosorbent assay (ELISA). The investigation revealed a significantly upregulated level of plasma LNC2 at the moderate stage of SARS-CoV-2 infection. In contrast, the levels of S100A8/A9 and CST3 in moderate patients were comparable to healthy controls; however, a profound induction was observed only in severe COVID-19 patients. The tissue injury marker myoglobin was unchanged in moderate patients; however, a significantly elevated level was observed in the critically ill COVID-19 patients. In contrast, cTnI level was unchanged both in moderate and severe patients. Analysis revealed a positive correlation between the levels of S100A8/A9 and CST3 with myoglobin in COVID-19. In silico analysis predicted interactions of S100A8/A9 with toll-like receptor 4 (TLR-4), MyD88 LY96, and LCN2 with several other inflammatory mediators including MMP2, MMP9, TIMP1, and interleukins (IL-6, IL-17A, and IL-10). In summary, early induction of LCN2 likely plays a role in advancing the COVID-19 severity. A positive correlation of S100A8/A9 and CST3 with myoglobin suggests that these proteins may serve as predictive biomarkers for thromboembolism and tissue injury in COVID-19.

Pulmonary Embolism: A Practical Guide for the Busy Clinician

Acute pulmonary embolism (PE) is the third most common acute cardiovascular condition, and its prevalence increases over time. D-dimer has a very high negative predictive value, and if normal levels of D-dimer are detected, the diagnosis of PE is very unlikely. The final diagnosis should be confirmed by computed tomographic scan. However, echocardiography is the most available, bedside, low-cost, diagnostic procedure for patients with PE. Risk stratification is of utmost importance and is mainly based on hemodynamic status of the patient. Patients with PE and hemodynamic stability require further risk assessment, based on clinical symptoms, imaging, and circulating biomarkers.

Evaluation of cardiac biomarkers and right ventricular dysfunction in patients with acute pulmonary embolism

OBJECTIVE

Right ventricular dysfunction (RVD) with myocardial damage may lead to fatal complications in patients with acute pulmonary embolism (PE). Cytoplasmic heart-type fatty acid-binding protein (HFABP) and the N-terminal fragment of its prohormone (NT-proBNP) are sensitive and specific biomarkers of myocardial damage. We evaluated RVD and cardiac biomarkers for myocardial damage and short-term mortality in patients with acute PE.

METHODS

We analyzed 41 patients (24 females, 17 males) with confirmed acute PE prospective. Three groups (massive, submassive, and non-massive) of patients were defined, based on systemic systolic blood pressure measured on admission and RVD by transthoracic echocardiography (TTE). Also, systolic (s) and mean (m) pulmonary artery pressures (PAPs) were recorded by TTE, and plasma concentrations of cardiac troponin T (cTn-T), NT-proBNP, and HFABP were evaluated 6 month follow-up.

RESULTS

Seventeen (41.5%) patients experienced a complicated clinical course in the 6-month follow-up for the combined end-point, including at least one of the following: death (n=12, 29.3%; 3 PE-related), chronic PE (n=4, 9.8%), pulmonary hypertension (n=2, 4.9%), and recurrent PE (n=1, 2.4%). Multivariate hazard ratio analysis revealed HFABP, NT-proBNP, and PAPs as the 6-month mortality predictors (HR 1.02, 95% CI 1.01-1.05; HR 1.01, 95% CI 1.01-1.04; and HR 1.02, 95% CI 1.02-1.05, respectively).

CONCLUSION

HFABP, NT-proBNP, and PAPs measured on admission may be useful for short-term risk stratification and in the prediction of 6-month PE-related mortality in patients with acute PE.

Comparison of biomarkers for predicting disease severity and long-term respiratory prognosis in patients with acute pulmonary embolism

Biomarkers are needed for early risk stratification and improved inpatient management to obtain better outcomes in acute pulmonary embolism (PE) patients. The aim of the present study was to evaluate biomarkers of right ventricular dysfunction (RVD) in order to predict a complicated clinical course and long-term respiratory complications in acute PE.We retrospectively enrolled 50 consecutive patients hospitalized for acute PE. Plasma brain natriuretic peptide (BNP), troponin-I, fibrin degradation products, D-dimer, C-reactive protein, and arterial pH were measured to assess their prognostic significance. RVD was evaluated by echocardiography at admission, the clinical course during hospitalization was monitored for the development of complications (death, cardiopulmonary resuscitation, mechanical ventilation or circulatory shock), and the need for home oxygen therapy (HOT) was assessed at/after discharge.Thirty-two patients (64%) had RVD at admission, 6 (12%) developed a complicated clinical course, and 7 (14%) required HOT. Plasma BNP was significantly higher in patients with RVD (median value, 319.3 versus 50.5 pg/mL, P = 0.001). Plasma BNP was also significantly higher (median value, 1307.9 versus 102.6 pg/mL, P = 0.02) and arterial pH significantly lower (acidic) (median value, 7.371 versus 7.438, P = 0.008) in patients who developed a complicated clinical course. In addition, plasma BNP was also significantly higher in patients who required HOT (median value, 505.1 versus 91.1 pg/mL, P = 0.02). Plasma BNP at admission is not only a reliable marker of RVD and predictor of short-term prognosis, but also a predictor of long-term respiratory prognosis in acute PE patients.

Prognostic stratification of acute pulmonary embolism: focus on clinical aspects, imaging, and biomarkers

Pulmonary embolism (PE) represents a common disease in emergency medicine and guidelines for diagnosis and treatment have had wide diffusion. However, PE morbidity and mortality remain high, especially when associated to hemodynamic instability or right ventricular dysfunction. Prognostic stratification to identify high risk patients needing to receive more aggressive pharmacological and closer monitoring is of utmost importance. Modern guidelines for management of acute PE are based on risk stratification using either clinical, radiological, or laboratory findings. This article reviews the modern treatment of acute PE, which is customized upon patient prognosis. Accordingly the current risk stratification tools described in the literature such as clinical scores, echocardiography, helical computer tomography, and biomarkers will be reviewed.

Diagnosis of pulmonary embolism in the coronary care unit

The clinical diagnosis of pulmonary embolism (PE) is difficult in coronary care units (CCUs) because many findings of PE are similar to those of acute coronary syndromes and heart failure. Immobilization of only 1 or 2 days may predispose to PE. Heart failure and acute myocardial infarction add to the risk. Dyspnea may be absent or occur only with exertion. The onset of dyspnea may occur over seconds to days. Orthopnea occurs with PE as well as heart failure. When the clinical probability and results of objective testing are discordant, the posttest probability of PE may be neither sufficiently high nor sufficiently low to permit therapeutic decisions. Objective scoring systems for clinical assessment have not been developed for patients in a CCU. d-dimer is likely to be of little value for the exclusion of PE in CCUs, because elevations occur with heart failure, unstable angina, and myocardial infarction. Computed tomographic pulmonary angiography with venous phase imaging of the low pelvic and proximal leg veins (computed tomographic venography) is recommended for imaging. Scintigraphy in women aged <50 years with normal or nearly normal results on chest x-ray may be the preferred imaging test to reduce the risk for radiation. Echocardiography with leg ultrasonography is a rapidly obtainable combination of bedside tests that may be useful for young patients and patients in extremis. In conclusion, the choice of diagnostic test depends on the clinical probability of PE, the condition of the patient, the availability of diagnostic tests, the risks of iodinated contrast material, radiation exposure, and cost.

Cardiac biomarkers for risk stratification in non-massive pulmonary embolism: a multicenter prospective study

BACKGROUND

Troponins (cTnI and cTnT), N-terminal pro-Brain Natriuretic Peptide (NT-proBNP), myoglobin, heart-type fatty acid-binding protein (H-FABP) and fibrin D-Dimer are emergent candidates for risk stratification in pulmonary embolism (PE).

OBJECTIVE

To compare the respective prognostic values of biomarker with non-massive PE to predict an adverse outcome at 3 months.

PATIENTS/METHODS

One hundred and forty-six consecutive patients with non-massive PE were included in this multicenter prospective study. The combined outcome consisted of intensive care monitoring on admission, death or hospitalization attributable to either a PE-related complication [defined by PE/deep vein thrombosis (DVT) relapse or major bleeding under anticoagulation] or to dyspnoea with or without chest pain during follow-up.

RESULTS

The outcome was met in 12% of patients. In univariate analysis, a NT-proBNP level above 300 pg/ml was the strongest predictor of unfavorable outcome with an odds ratio (OR) of 15.8 [95% confidence interval (CI): 2.05-122). ORs for the other variables were: 8.0 for D-dimer >2000 ng/ml (95% CI: 1.1-64), 4.7 for H-FABP >6 ng/ml (95% CI:1.5-14.8), 3.5 for cTnI >0.09 ng/ml (95% CI:1.2-9.7), 3.4 for myoglobin >70 ng/ml (95% CI:0.9-12.2). Receiver operating curve (ROC) analysis indicated that NT-proBNP was the best predictor [area under the curve (AUC) 0.84; 95%CI: 0.76-0.92; P < 0.0001] with a negative predictive value of 100% (95% CI: 91-100) at 300 pg/ml. At that cut-off, the true negative rate for NT-proBNP was 40%. In multivariate analysis, NT-proBNP was the only significant independent predictors.

CONCLUSIONS

NT-proBNP appears to be a good risk stratification marker in identifying low-risk patients with non-massive PE who could be treated in an outpatient setting.

Correlation between cardiac biomarkers and right ventricular enlargement on chest CT in non massive pulmonary embolism

BACKGROUND

Troponin I (cTnI), myoglobin, heart-type fatty acid binding protein (H-FABP), and natriuretic peptides (BNP, NTproBNP) were all reported to be elevated in patients with pulmonary embolism (PE).

METHODS

To assess the correlation between the aforementioned markers and helical computed tomography (hCT) right ventricular dysfunction (RVD) in non massive PE, we performed this prospective pilot study on 50 patients.

RESULTS

Patients with RVD had significant higher natriuretic peptides prevalence than cardiomyocytes damage-related markers (48% vs 20%, P=0.006). Significant prevalence differences were observed only for natriuretic peptides when patients with RVD and those without were compared (74% vs 33% for NT-pro BNP, P=0.005 and 65% vs 22% for BNP, P=0.003). Patients with RVD had significant higher biomarkers median plasmatic values than those without (BNP: 170 vs 36 pg/ml, P=0.0027; NT-proBNP: 1369 vs 170.7 pg/ml, P=0.0024; cTnI: 0.032 vs 0 ng/ml, P=0.0034; H-FABP: 4.32 vs 2.23 ng/ml, P=0.0032; myoglobin: 36.7 vs 28.2 ng/ml, P=0.03). Significant correlations were only obtained between RV/LV index and plasmatic natriuretic peptides (NT-proBNP: r=0.36, P=0.009; BNP r=0.28; P=0.047).

CONCLUSIONS

Natriuretic peptides prevalence elevation and median values are significantly higher when RVD is present and significantly correlate with hCT RVD.

Prognostic value of serum myoglobin in patients after cardiac surgery

PURPOSE

Serum myoglobin as a marker of myocardial damage and injury has been shown to be of prognostic value in patients with cardiovascular events. In this study, we analyzed the prognostic value of serum myoglobin in comparison to other parameters of muscle damage and renal function in patients after cardiac surgery.

METHODS

We retrospectively analyzed data from 373 cardiac surgical patients (mean age, 66 +/- 10 years; range, 30-88 years) by using the highest levels of serum myoglobin, creatinine, and creatine phosphokinase (CK) within the first 24 h after admission to the Intensive Care Unit (ICU). Patients' severity of illness was assessed by the Acute Physiology and Chronic Health Evaluation (APACHE) II score. Predictive properties, in terms of ICU mortality and need for renal replacement therapy (RRT), were analyzed by receiver operating characteristics (ROC) statistics and described by the area under the curve (AUC).

RESULTS

Serum myoglobin was significantly higher in nonsurvivors (n = 29) than in survivors (n = 344; median, 1449 vs 356 microg x l(-1); P < 0.001). With respect to ICU mortality, AUCs were 0.81 for myoglobin, 0.80 for creatinine, and 0.63 for CK. For comparison, an AUC of 0.82 was found for the APACHE II score. In terms of the need for RRT, AUCs were 0.87 for myoglobin, 0.92 for creatinine, and 0.60 for CK. For both endpoints, the AUCs of myoglobin and creatinine were significantly higher than that for CK.

CONCLUSION

Serum myoglobin is associated with outcome in patients after cardiac surgery. Prediction of ICU mortality and need for RRT was comparable for myoglobin and creatinine, while both were significantly superior to CK.

Acute pulmonary embolism: risk stratification in the emergency department

Pulmonary embolism is a common disease associated with a high mortality rate. Death due to pulmonary embolism occurs more commonly in undiagnosed patients before hospital admission or during the initial in-hospital stay. Thus, mortality could be reduced by prompt diagnosis, early prognostic stratification and more intensive treatment in patients with adverse prognosis. Mortality is particularly high in patients with pulmonary embolism presenting with arterial hypotension or cardiogenic shock. In patients with pulmonary embolism and normal blood pressure, a number of clinical features and objective findings have been associated with a high risk of adverse in-hospital outcome. Advanced age and concomitant cardiopulmonary disease are clinical risk factors for in-hospital mortality. The Bburden of thromboembolism, as assessed by lung scan or spiral CT, and right ventricle overload, as assessed by echocardiography and probably spiral CT, have been claimed to be risk factors for in-hospital mortality. Elevated serum levels of troponins have been shown to be associated with right ventricular overload and adverse in-hospital outcomes in patients with pulmonary embolism. Despite the currently available evidence, no definite prognostic value can be assigned to any of the individual risk factors or cluster of them. Large prospective trials should be carried out to validate individual risk factors or clusters of risk factors able to identify patients with acute pulmonary embolism at high risk for in-hospital mortality. These patients could afford the trade-off of an increased risk of side effects related to a more aggressive treatment, such as thrombolysis or surgical or interventional procedures.

Biomarkers in pulmonary embolism

PURPOSE OF REVIEW

Controversy exists about the precise role of thrombolytic therapy in normotensive patients with pulmonary embolism. To resolve this controversy two major questions must be addressed. First, can a subgroup of normotensive pulmonary embolism patients with a high risk for adverse outcomes, such as in-hospital mortality or early recurrent venous thromboembolism, be identified? Second, is there convincing evidence that the benefits of more aggressive therapy counterbalance its risks?Troponin I and T as well as brain natriuretic peptide (BNP) have recently been introduced as promising tools in the risk assessment of patients with pulmonary embolism.

RECENT FINDINGS

The studies in series of patients with pulmonary embolism showed prevalences of elevated cardiac biomarkers of 16 to 84%. Positive predictive values for in-hospital mortality varied from 6 to 44%, whereas negative predictive values for uneventful outcome were above 93% in all studies.

SUMMARY

Although a correlation between elevated biomarkers and in-hospital mortality in pulmonary embolism patients is present in most of the studies, the positive predictive value appears to be insufficient to extend the indication for thrombolytic therapy to all patients with elevated biomarkers. Future research is necessary to show whether combining different biomarkers with echocardiography is more useful.