Prognostic value of troponins in acute pulmonary embolism: a meta-analysis

Are clinical parameters and biomarkers predictive of severity of acute pulmonary emboli on CTPA?

BACKGROUND

Previous studies have shown that findings of computed tomography pulmonary angiography (CTPA) relate to outcome in pulmonary embolus (PE). These include clot burden as quantified using an obstruction index and markers of pressure overload such as right ventricle to left ventricle size ratio (RV/LV ratio). Little data exists correlating these findings with clinical presentation and biomarkers.

AIM

To explore the link between clinical presentation and biomarkers with CTPA findings.

METHODS

Retrospective case note analysis of consecutive cases presenting to a large teaching hospital. An independent radiologist reviewed CTPAs and clot burden quantified using an obstruction index.

RESULTS

One hundred and seventy cases were identified and notes retrieved in 137 cases. (i)

CLINICAL PRESENTATION

correlation was seen between clot burden and systolic blood pressure (BP) (r = -0.299, P = 0.0006) and heart rate (r = 0.240, P = 0.0056). Median obstruction index was significantly higher in those with a presenting BP <90 mmHg [41.25% (95% CI 30-50) vs. 15% (95% CI 12.5-25), (P = 0.0004)]. Clot burden was significantly higher in patients with temperature of >37.5 degrees C [30% (95% CI 25.0-42.5) vs. 15% (95% CI 12.5-28.3), P = 0.02)] and (ii)Biomarkers: significant correlation between clot burden and D-dimer was seen (r = 0.36, P = 0.0001). Location of thrombus was associated with significant differences in D-dimer level. A subgroup of patients had cardiac biomarkers measured (n = 24). There was a statistically significant correlation between troponin I and clot burden (r = 0.412, P = 0.048) and RV/LV ratio (r = 0.699, P = 0.0013).

DISCUSSION

These findings suggest that clinical parameters and biomarkers have a role in predicting the radiological severity of PE. These data support the need for further studies of risk stratification in patients presenting with acute PE.

Clinical, historical and diagnostic findings associated with right ventricular dysfunction in patients with central and non-massive pulmonary embolism

Right ventricular dysfunction during acute pulmonary embolism (PE) predisposes to hemodynamic instability and cardiogenic shock. Aim of this case-control study was to determine the clinical, historical and diagnostic findings associated with right ventricular dysfunction in patients with acute PE involving the main or segmental pulmonary arteries (central PE) and without hemodynamic instability on admission to the Emergency Department (ED) (non-massive PE). From January 1, 2002 to December 31, 2005, 211 patients with central PE were admitted to the Department of Emergency Medicine of the "Antonio Cardarelli" Hospital (Naples, Italy). One hundred eighteen of them had echocardiographic evidence of right ventricular dysfunction on admission to the ED. A history of type 2 diabetes mellitus and chronic obstructive pulmonary disease were significantly associated with an increased risk of this PE-related complication. Compared to patients without right ventricular dysfunction, those with right ventricular dysfunction showed higher levels of markers of cardiac damage, and a significant impairment of respiratory function. Echocardiographic evidence of right ventricular dysfunction on admission to the ED was significantly associated with the occurrence of hemodynamic instability and cardiogenic shock during the PE clinical course. The study results indicate that a history of type 2 diabetes mellitus and chronic obstructive pulmonary disease are significantly associated with the occurrence of right ventricular dysfunction in patients with non-massive and central PE independent of age, gender and other historical and clinical variables detectable on admission to the ED.

Right ventricular heart failure from pulmonary embolism: key distinctions from chronic pulmonary hypertension

BACKGROUND

The right ventricle normally operates as a low pressure, high-flow pump connected to a high-capacitance pulmonary vascular circuit. Morbidity and mortality in humans with pulmonary hypertension (PH) from any cause is increased in the presence of right ventricular (RV) dysfunction, but the differences in pathology of RV dysfunction in chronic versus acute occlusive PH are not widely recognized.

METHODS AND RESULTS

Chronic PH that develops over weeks to months leads to RV concentric hypertrophy without inflammation that may progress slowly to RV failure. In contrast, pulmonary embolism (PE) results in an abrupt vascular occlusion leading to increased pulmonary artery pressure within minutes to hours that causes immediate deformation of the RV. RV injury is secondary to mechanical stretch, shear force, and ischemia that together provoke a cytokine and chemokine-mediated inflammatory phenotype that amplifies injury.

CONCLUSIONS

This review will briefly describe causes of pulmonary embolism and chronic PH, models of experimental study, and pulmonary vascular changes, and will focus on mechanisms of right ventricular dysfunction, contrasting mechanisms of RV adaptation and injury in these 2 settings.

[Diagnosis, therapy and secondary prophylaxis of acute pulmonary embolism. Presentation of and commentary on the new ESC 2008 guidelines]

Acute venous thromboembolism is a common cardiovascular emergency. Acute pulmonary embolism (PE) is present in one third of these patients. With an average lethality rate of 11% within the first two weeks following diagnosis, approximately 40,000 patients in Germany die annually as a result of PE; therefore, their diagnosis and therapy is of particular importance. For this reason, the European Society of Cardiology published guidelines on diagnosis and therapy in 2000. The current article presents and discusses the points as updated and extended in the 2008 version of the guidelines, including: (1) initial risk stratification--when PE is already suspected; (2) diagnostic procedures and algorithms; (3) further risk stratification; (4) therapeutic strategies in the acute phase; (5) further management and (6) long-term anticoagulation and secondary prophylaxis.

[Update in pulmonary thromboembolic disease]

Pulmonary embolism is part of venous thromboembolism, an important health problem which leads to significant mortality and morbidity with high economic and social burden. A prompt diagnosis and treatment as well as an appropriate prophylaxis are determinant factors in prognosis. This disease continues to demand particular attention namely in the investigation of risk factors, clinical probability algorithms development, diagnostic work-up evaluation, characterization of new therapeutic strategies and thromboprophylaxis recommendations. The present review looks into the current scientific knowledge regarding pulmonary embolism.

The correlation between elevated cardiac troponin I and pulmonary artery obstruction index in ED patients with pulmonary embolism

OBJECTIVES

The aim of this study is to investigate the correlation between cardiac troponin I (cTnI) values and the pulmonary artery obstruction index assessed with spiral computed tomography (CT) scan in emergency department (ED) patients with pulmonary embolism (PE).

METHODS

This is a retrospective cohort study of all 179 ED patients diagnosed with PE between December 2004 and January 2007. Study population consisted of 104 (58.1%) of 179 patients with PE in whom both cTnI was measured and a contemporaneously performed CT scan was available for review. In these patients, the levels of cTnI measured in the ED were correlated with the degree of pulmonary vascular obstruction determined by applying the modified Computed Tomography Obstruction Index to the spiral CT scan performed in the ED.

RESULTS

Troponin values were elevated in 20 (19.2%) of 104 patients (95% confidence interval [CI], 11.6-26.8) with a mean cTnI concentration of 0.38 +/- 0.44 microg/L. Elevated cTnI value had a significant correlation with main pulmonary arteries involvement using the modified Computed Tomography Obstruction Index score (P = .0001). Elevated ED cTnI value had 53.8% (95% CI, 37.6-66) sensitivity and 92.3% (95% CI, 87-96.4) specificity, 70% (95% CI, 49-86) PPV, and 85.7% (95% CI, 80.7-90) NPV for predicting main pulmonary artery obstruction on CT. Increased cTnI values were highly correlated to intensive care unit admission of patients with PE (RR, 12.83; 95% CI, 3.87-42.4).

CONCLUSIONS

Measuring cTnI value might be considered in ED patients who are suspected of having PE. Elevated cTnI should raise the clinician's concern for the possibility of central pulmonary vascular obstruction.

Determinants of cardiac troponin T elevation in COPD exacerbation - a cross-sectional study

Background

Cardiac Troponin T (cTnT) elevation during exacerbations of chronic obstructive pulmonary disease (COPD) is associated with increased mortality the first year after hospital discharge. The factors associated with cTnT elevation in COPD are not known.

Methods

From our hospital's database, all patients admitted with COPD exacerbation in 2000–03 were identified. 441 had measurement of cTnT performed. Levels of cTnT ≥ 0.04 μg/l were considered elevated. Clinical and historical data were retrieved from patient records, hospital and laboratory databases. Odds ratios for cTnT elevation were calculated using logistic regression.

Results

120 patients (27%) had elevated cTnT levels. The covariates independently associated with elevated cTnT were increasing neutrophil count, creatinine concentration, heart rate and Cardiac Infarction Injury Score (CIIS), and decreasing hemoglobin concentration. The adjusted odds ratios (95% confidence intervals in parentheses) for cTnT elevation were 1.52 (1.20–1.94) for a 5 × 10⁶/ml increase in neutrophils, 1.21 (1.12–1.32) for a 10 μmol/l increase in creatinine, 0.80 (0.69–0.92) for a 1 mg/dl increase in hemoglobin, 1.24 (1.09–1.42) for a 10 beats/minute increase in heart rate and 1.44 (1.15–1.82) for a 10 point increase in CIIS.

Conclusion

Multiple factors are associated with cTnT elevation, probably reflecting the wide panorama of comorbid conditions typically seen in COPD. The positive association between neutrophils and cTnT elevation is compatible with the concept that an exaggerated inflammatory response in COPD exacerbation may predispose for myocardial injury.

Clinical significance of borderline elevated troponin I levels across different assays in patients with suspected acute coronary syndrome

We aimed to elucidate the clinical significance of borderline troponin I (TnI) increases and see if such increases are of similar significance across different assays. Markedly increased TnI is a strong predictor of adverse cardiac events. It is not clear if borderline increases with different commercially available TnI assays provide similar prognostic information. From January 2001 to February 2004, 3 different TnI assays (Beckman Access TnI, Beckman Access AccuTnI, and Vitros ECI Troponin) were used to evaluate the peak TnI value in 1,152 consecutive patients admitted with suspected acute coronary syndrome/non-ST-elevation myocardial infarction (MI). Recommended cutoffs were used to differentiate borderline from marked increases reported as consistent with MI. Clinical data and 30-day death/new MIs were determined by chart abstraction. Demographics and cardiac risk factors were similar for the 3 groups. Frequency of borderline TnI ranged widely among assays (18.7% to 42.1%) but was significantly less with the Vitros ECI Troponin assay (p <0.0001). Prognostic significance of borderline increased TnI values also varied greatly by assay, with borderline Beckman Access AccuTnI increases being predictive of adverse 30-day outcomes (odds ratio 4.0, 95% confidence interval 1.46 to 10.97, p = 0.007), but not with the other 2 assays. Borderline increases were significantly associated with chronic renal insufficiency (CRI; serum creatine >1.5); the relation to adverse 30-day outcomes and borderline increases persisted after correcting for CRI in a multivariate logistic regression model. In conclusion, although borderline increased TnI levels are common and significantly associated with CRI, they do not all portend the same clinical prognosis. This study highlights the need for standardization of TnI levels across different assays.

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.

Advanced treatment strategies for acute pulmonary embolism, including thrombolysis and embolectomy

The optimal treatment strategy for acute pulmonary embolism relies upon a multidisciplinary team that rapidly assesses available data, performs additional testing if necessary, weighs treatment options, and recommends an appropriate therapeutic plan to the patient and family. Round-the-clock availability is imperative. Centers that specialize in pulmonary embolism management offer a wide range of therapeutic options. Hospitals with more limited facilities should establish pulmonary embolism patient referral and transfer contingency plans that can be activated at a moment's notice. Management options include anticoagulation alone, thrombolysis plus anticoagulation, insertion of an inferior vena caval filter, catheter embolectomy, or surgical embolectomy. The decision-making process requires accurate risk stratification, which is comprised of several crucial components: clinical evaluation that includes history and physical examination, biomarker measurement especially of troponin, as well as assessment of right ventricular size and function based upon chest CT scanning and echocardiography. The 'old school' approach of declaring a benign prognosis based solely upon the presence of normal systemic arterial pressure can delay advanced therapy until after the onset of irreversible cardiogenic shock. We have now formulated a more contemporary, comprehensive, and multifaceted strategy to prognosticate. Our 'new approach' uses advanced treatment strategies in addition to anticoagulation for those pulmonary embolism patients deemed to be at high risk for a poor outcome.

Short-term prognosis of pulmonary embolism

Risk stratification tools that accurately quantify the prognosis of patients with pulmonary embolism (PE) may be useful in guiding medical decision making. Prospective studies demonstrated that clinical factors, echocardiographic right ventricular dysfunction, and cardiac biomarkers (troponins, brain natriuretic peptides) are independent predictors of short-term mortality in patients with PE. The presence of systemic hypotension or shock carries the highest risk of death, and thrombolysis is usually indicated. Among hemodynamically stable patients, clinical prognostic models, echocardiography, and biomarkers accurately identify low-risk patients with PE who are potential candidates for less costly outpatient care. However, the practical use of these prognostic measures is currently limited by the lack of studies demonstrating a positive impact on patient care. The benefit of risk stratification strategies based on clinical prognostic models, echocardiography, and cardiac biomarkers should be demonstrated in prospective studies before their implementation as decision aid to guide initial treatment can be recommended.

Risk stratification and outcomes in hemodynamically stable patients with acute pulmonary embolism: a prospective, multicentre, cohort study with three months of follow-up

BACKGROUND

The role of risk stratification in normotensive patients with acute pulmonary embolism (PE) is still unclear.

OBJECTIVES

We evaluated, in these patients, the usefulness of six prognostic markers for predicting in-hospital adverse events related to PE and 3-month mortality.

PATIENTS/METHODS

Two hundred and one consecutive patients with confirmed acute PE and normal blood pressure, who were administered conventional anticoagulation, were recruited in a multicentre prospective cohort study with 3 months of follow-up. At baseline, they received a comprehensive risk-evaluation including echocardiographic assessment of right ventricular dysfunction, determination of troponin I, brain natriuretic peptide and D-dimer, arterial blood gas analysis and a clinical score. Primary outcome of the study was PE-related in-hospital death or clinical deterioration. Secondary outcomes were in-hospital and 3-month all-cause mortality.

RESULTS

The primary outcome occurred in one patient (0.5%), who died from PE during hospitalization. The in-hospital and 3-month all-cause mortality were 2% and 9%, respectively. None of the prognostic markers was predictive of the primary outcome. Clinical score, troponin I and hypoxemia predicted in-hospital all-cause mortality (P = 0.02, 0.01 and < 0.01, respectively). Clinical score (HR, 4.7; 95% CI, 1.9-12.0), D-dimer (4.8; 1.4-16.3), hypoxemia (5.7; 2.1-15.1) and troponin I (7.5; 2.5-22.7) were predictors of 3-month all-cause mortality on univariate analysis. On multivariate analysis clinical score and troponin I remained independently predictive.

CONCLUSIONS

We did not find prognostic markers useful as predictors of in-hospital PE-related adverse events. Clinical score, troponin I and hypoxemia predicted in-hospital all-cause mortality. Clinical score and troponin I independently predicted 3-month all-cause mortality.

The Risk-based Treatment of Acute Pulmonary Embolism

Risk evaluation and prognostic stratification based upon clinical and radiological findings and new cardiac biomarkers, such as natriuretic peptides (NP) and troponins, represent key points in modern management of acute pulmonary embolism (PE). Literature evidence shows that normotensive PE with right heart dysfunction (RHD), defined as submassive PE, has poorer prognosis when compared to normotensive PE without RHD, defined as non-massive PE; thus whether submassive PE should be managed more aggressively and with closer monitoring represents the crucial question about acute PE treatment. Although the answer is yet unclear, the most recent guidelines address to thrombolysis as treatment choice in selected high risk patients with submassive PE. Guidelines also clarify the indications for unfractioned and low molecular weight heparins and fondaparinux. Therefore, in the present article, the authors focus on modern risk-based therapeutic guidelines of acute PE.

KEYWORDS

Pulmonary embolism; Treatment; Prognosis; Biomarkers; Chocardiography; Hemodynamic; Guidelines.

Acute heart failure: How to evaluate left ventricular filling pressure in practice?

Heart failure is one of the most frequent reasons for hospitalization due to a cardiac event. In most instances, the main difficulty is how to accurately evaluate left ventricular filling pressure. It can be evaluated clinically, biologically and invasively. Although historically, invasive management has been the reference, it is being used less and less frequently and expertise in the technique is being lost. This paper discusses the strength and weaknesses of the different techniques for evaluating filling pressure in these patients, and the importance of this parameter for their optimal treatment.

Pulmonary embolism in the elderly: a review on clinical, instrumental and laboratory presentation

Objective

Diagnosis of pulmonary embolism (PE) remains difficult and is often missed in the elderly due to nonspecific and atypical presentation. Diagnostic algorithms able to rule out PE and validated in young adult patients may have reduced applicability in elderly patients, which increases the number of diagnostic tools use and costs. The aim of the present study was to analyze the reported clinical presentation of PE in patients aged 65 and more.

Materials and Methods

Prospective and retrospective English language studies dealing with the clinical, instrumental and laboratory aspects of PE in patients more than 65 and published after January 1987 and indexed in MEDLINE using keywords as pulmonary embolism, elderly, old, venous thromboembolism (VTE) in the title, abstract or text, were reviewed.

Results

Dyspnea (range 59%–91.5%), tachypnea (46%–74%), tachycardia (29%–76%), and chest pain (26%–57%) represented the most common clinical symptoms and signs. Bed rest was the most frequent risk factor for VTE (15%–67%); deep vein thrombosis was detected in 15%–50% of cases. Sinus tachycardia, right bundle branch block, and ST-T abnormalities were the most frequent ECG findings. Abnormalities of chest X-ray varied (less than 50% in one-half of the studies and more than 70% in the other one-half). Arterial blood gas analysis revealed severe hypoxemia and mild hypocapnia as the main findings. D-Dimer was higher than cut-off in 100% of patients in 75% of studies. Clinical usefulness of D-Dimer measurement decreases with age, although the strategies based on D-Dimer seem to be cost-effective at least until 80 years.

Conclusion

Despite limitations due to pooling data of heterogeneous studies, our review could contribute to the knowledge of the presentation of PE in the elderly with its diagnostic difficulties. A diagnostic strategy based on reviewed data is proposed.

Guidelines on the diagnosis and management of acute pulmonary embolism: the Task Force for the Diagnosis and Management of Acute Pulmonary Embolism of the European Society of Cardiology (ESC)

Non-thrombotic PE does not represent a distinct clinical syndrome. It may be due to a variety of embolic materials and result in a wide spectrum of clinical presentations, making the diagnosis difficult. With the exception of severe air and fat embolism, the haemodynamic consequences of non-thrombotic emboli are usually mild. Treatment is mostly supportive but may differ according to the type of embolic material and clinical severity.

Antithrombotic therapy for venous thromboembolic disease: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition)

This chapter about treatment for venous thromboembolic disease is part of the American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Grade 1 recommendations are strong and indicate that the benefits do or do not outweigh risks, burden, and costs. Grade 2 suggests that individual patient values may lead to different choices (for a full understanding of the grading, see "Grades of Recommendation" chapter). Among the key recommendations in this chapter are the following: for patients with objectively confirmed deep vein thrombosis (DVT) or pulmonary embolism (PE), we recommend anticoagulant therapy with subcutaneous (SC) low-molecular-weight heparin (LMWH), monitored IV, or SC unfractionated heparin (UFH), unmonitored weight-based SC UFH, or SC fondaparinux (all Grade 1A). For patients with a high clinical suspicion of DVT or PE, we recommend treatment with anticoagulants while awaiting the outcome of diagnostic tests (Grade 1C). For patients with confirmed PE, we recommend early evaluation of the risks to benefits of thrombolytic therapy (Grade 1C); for those with hemodynamic compromise, we recommend short-course thrombolytic therapy (Grade 1B); and for those with nonmassive PE, we recommend against the use of thrombolytic therapy (Grade 1B). In acute DVT or PE, we recommend initial treatment with LMWH, UFH or fondaparinux for at least 5 days rather than a shorter period (Grade 1C); and initiation of vitamin K antagonists (VKAs) together with LMWH, UFH, or fondaparinux on the first treatment day, and discontinuation of these heparin preparations when the international normalized ratio (INR) is > or = 2.0 for at least 24 h (Grade 1A). For patients with DVT or PE secondary to a transient (reversible) risk factor, we recommend treatment with a VKA for 3 months over treatment for shorter periods (Grade 1A). For patients with unprovoked DVT or PE, we recommend treatment with a VKA for at least 3 months (Grade 1A), and that all patients are then evaluated for the risks to benefits of indefinite therapy (Grade 1C). We recommend indefinite anticoagulant therapy for patients with a first unprovoked proximal DVT or PE and a low risk of bleeding when this is consistent with the patient's preference (Grade 1A), and for most patients with a second unprovoked DVT (Grade 1A). We recommend that the dose of VKA be adjusted to maintain a target INR of 2.5 (INR range, 2.0 to 3.0) for all treatment durations (Grade 1A). We recommend at least 3 months of treatment with LMWH for patients with VTE and cancer (Grade 1A), followed by treatment with LMWH or VKA as long as the cancer is active (Grade 1C). For prevention of postthrombotic syndrome (PTS) after proximal DVT, we recommend use of an elastic compression stocking (Grade 1A). For DVT of the upper extremity, we recommend similar treatment as for DVT of the leg (Grade 1C). Selected patients with lower-extremity (Grade 2B) and upper-extremity (Grade 2C). DVT may be considered for thrombus removal, generally using catheter-based thrombolytic techniques. For extensive superficial vein thrombosis, we recommend treatment with prophylactic or intermediate doses of LMWH or intermediate doses of UFH for 4 weeks (Grade 1B).

Prognostic value of brain natriuretic peptide in acute pulmonary embolism

INTRODUCTION

The relationship between brain natriuretic peptide (BNP) increase in acute pulmonary embolism (PE) and the increase in mortality and morbidity has frequently been suggested in small studies but its global prognostic performance remains largely undefined. We performed a systematic review and meta-analysis of data to examine the prognostic value of elevated BNP for short-term all-cause mortality and serious adverse events.

METHODS

The authors reviewed PubMed, BioMed Central, and the Cochrane database and conducted a manual review of article bibliographies. Using a prespecified search strategy, we included a study if it used BNP or N-terminal pro-BNP biomarkers as a diagnostic test in patients with documented PE and if it reported death, the primary endpoint of the meta-analysis, in relation to BNP testing. Studies were excluded if they were performed in patients without certitude of PE or in a subset of patients with cardiogenic shock. Twelve relevant studies involving a total of 868 patients with acute PE at baseline were included in the meta-analysis using a random-effects model.

RESULTS

Elevated BNP levels were significantly associated with short-term all-cause mortality (odds ratio [OR] 6.57, 95% confidence interval [CI] 3.11 to 13.91), with death resulting from PE (OR 6.10, 95% CI 2.58 to 14.25), and with serious adverse events (OR 7.47, 95% CI 4.20 to 13.15). The corresponding positive and negative predictive values for death were 14% (95% CI 11% to 18%) and 99% (95% CI 97% to 100%), respectively.

CONCLUSION

This meta-analysis indicates that, while elevated BNP levels can help to identify patients with acute PE at high risk of death and adverse outcome events, the high negative predictive value of normal BNP levels is certainly more useful for clinicians to select patients with a likely uneventful follow-up.

Comparison of 8 biomarkers for prediction of right ventricular hypokinesis 6 months after submassive pulmonary embolism

BACKGROUND

Elevated blood concentrations of troponin proteins or brain natriuretic peptide (BNP) worsen the prognosis of patients with pulmonary embolism (PE). Novel biomarkers that reflect mechanisms of right ventricle (RV) damage from PE may provide additional prognostic value. We compare the prognostic use of BNP, troponin I, D-dimer, monocyte chemoattractant protein-1, matrix metalloproteinase, myeloperoxidase, C-reactive protein, and caspase 3 as biomarkers of RV damage and adverse outcomes in submassive PE.

METHODS

This article used a prospective cohort study of normotensive (systolic blood pressure always >100 mm Hg) patients with computed tomographic angiography-diagnosed PE. All patients underwent echocardiography and phlebotomy at diagnosis, and survivors had another echocardiography 6 months later. We tested each biomarker for prognostic significance, requiring a lower limit 95% CI >0.50 for the area under the receiver operating characteristic curve (AUROC) with a reference standard positive of RV hypokinesis on either echocardiogram. Biomarkers with prognostic significance were dichotomized at the concentration that yielded highest likelihood ratio positive and mortality rates compared (Fisher exact test).

RESULTS

We enrolled 152 patients with complete data. Thirty-seven (24%, 95% CI 18%-32%) had RV hypokinesis. Only BNP and troponin had significant AUROC values as follows: 0.71 (95% CI 0.60-0.81) and 0.71 (95% CI 0.62-0.82), respectively. Overall mortality was 13/153 (8.5%); mortality rate for BNP >100 versus < or =100 pg/mL was 23% versus 3% (P = .003), respectively. Mortality rate for troponin I >0.1 versus < or =0.1 ng/mL was 13% versus 6% (P = .205), respectively.

CONCLUSIONS

Of 8 mechanistically plausible biomarkers, only BNP and troponin I had significant prognostic use with BNP having an advantage for predicting mortality.

Brain-type natriuretic peptide levels in the prediction of adverse outcome in patients with pulmonary embolism: a systematic review and meta-analysis

RATIONALE

The potential role of elevated brain-type natriuretic peptides (BNP) in the differentiation of patients suffering from acute pulmonary embolism at risk for adverse clinical outcome has not been fully established.

OBJECTIVES

We evaluated the relation between elevated BNP or N-terminal-pro-BNP (NT-pro-BNP) levels and clinical outcome in patients with pulmonary embolism.

METHODS

Articles reporting on studies that evaluated the risk of adverse outcome in patients with pulmonary embolism and elevated BNP or NT-pro-BNP levels were abstracted from Medline and EMBASE. Information on study design, patient and assay characteristics, and clinical outcome was extracted. Primary endpoints were overall mortality and predefined composite outcome of adverse clinical events.

MEASUREMENTS AND MAIN RESULTS

Data from 13 studies were included. In 51% (576/1,132) of the patients, BNP or NT-pro-BNP levels were increased. The different analyses were performed in subpopulations. Elevated levels of BNP or NT-pro-BNP were significantly associated with right ventricular dysfunction (P < 0.001). Patients with high BNP or NT-pro-BNP concentration were at higher risk of complicated in-hospital course (odds ratio [OR], 6.8; 95% confidence interval [CI], 4.4-10) and 30-day mortality (OR, 7.6; 95% CI, 3.4-17). Patients with a high NT-pro-BNP had a 10% risk of dying (68/671; 95% CI, 8.0-13%), whereas 23% (209/909; 95% CI, 20-26%) had an adverse clinical outcome.

CONCLUSIONS

High concentrations of BNP distinguish patients with pulmonary embolism at higher risk of complicated in-hospital course and death from those with low BNP levels. Increased BNP or NT-pro-BNP concentrations alone, however, do not justify more invasive treatment regimens.

Troponin I and right ventricular dysfunction for risk assessment in patients with nonmassive pulmonary embolism in the Emergency Department in combination with clinically based risk score

To determine whether troponin I (cTnI) and right ventricular (RV) dysfunction predict adverse in-hospital outcomes in patients admitted to the Emergency Department (ED) with definite nonmassive pulmonary embolism (PE) independent of and in addition to a recently validated clinical prognostic risk score. From a pool of 168 patients with suspected PE, 89 had nonmassive PE confirmed by spiral lung angio-computed tomography. By the clinical prognostic score, in our study sample, 14% had very low risk; 17% had low risk, 20% had intermediate risk, whereas high risk and very high risk were identified in 29 and 20%, respectively. Prevalence of elevated cTnI (>0.1 microg/L, 57%) at admission was comparable among patients grouped by clinical prognostic score (P = NS); echocardiographic RV dysfunction (54%) was more prevalent with intermediate or high clinical risk score (P < 0.02). Increased cTnI predicted primary end-point (development of hemodynamic instability, overall 33 cases, 37%) independent of and in addition to the clinical risk class and RV dysfunction (P < 0.01 for interaction). Fatal events (12 cases, 14%, 5 definite, 7 possible PE-related) were predicted by higher clinical risk score (P < 0.05). In patients with nonmassive central PE admitted to the ED, increased cTnI contributed to identifying those with increased risk of development of hemodynamic instability independent of and in addition to a validated clinically based risk score.