The accuracy of combined use of troponin and red cell distribution width in predicting mortality of patients with acute pulmonary embolism

Association of Inflammatory Markers with Mortality in Patients Hospitalized with Non-massive Pulmonary Embolism

OBJECTIVE

Pulmonary embolism (PE) is a serious pathology with high rates of morbidity and mortality. Studies regarding the efficacy of new inflammatory markers as a predictor of mortality in PE have thus far been limited. This study aimed to evaluate the predictive value of platelet/lymphocyte ratio (PLR), neutrophil/lymphocyte ratio (NLR), platelet/mean platelet volume (PLT/MPV), and C-reactive protein (CRP) on short-term and long-term mortality in patients with PE.

MATERIAL AND METHODS

A retrospective, observational cohort study was carried out in a tertiary teaching hospital. Patients with PE hospitalized in the pulmonology ward were enrolled. Their characteristics, hemogram parameters, PLR, NLR, CRP levels, PLT/MPV on admission, and mortality were recorded. The predictive accuracies of inflammatory markers were determined through receiver operating characteristic curves. The risk factors for mortality were further analyzed with Cox regression analysis.

RESULTS

A total of 828 patients with PE were included in the study. The 1-month mortality was 1%, and the 1-year mortality was 8.5%. An NLR value above 6 was associated with an almost 13-fold increase in short-term (30-day) mortality. We found that an NLR above 3.15 and age were independent risk factors for long-term (1-year) mortality. The other inflammatory markers, namely PLR and CRP, were not found to be associated with long-term mortality.

CONCLUSION

PE is a serious condition in the elderly. Elevated NLR values appear to be a good and feasible predictor of inflammation, which can be correlated with higher mortality over both the short-term and long-term periods.

Red cell distribution width for prognosis in patients with pulmonary embolism: A systematic review and meta-analysis

OBJECTIVES

Patients with pulmonary embolism (PE) have a higher red cell distribution width (RDW), which may complicate the interpretation of the prognosis of PE. We aim to evaluate the diagnostic utility of the RDW in patients with PE.

METHODS

Eligible studies were identified by searching PubMed and EMBASE from inception to December 23, 2018. The data were pooled using Stata 12 to evaluate the prognostic value. The sources of heterogeneity were detected.

RESULTS

For the analysis of prognosis, 7 studies with 2146 patients were included, with median RDW values ranging from 13.4% to 15.7% and a median cut-off point of 18.27%. A total of 247 patients (11.5% mortality) among the 2146 participants died. Overall, RDW was positively associated with the prognosis of PE in the overall analysis (HR = 1.19, 95% CI = 1.10-1.29, I2  = 73.4%; P = 0.000). Subgroup analyses by study design, sex and follow-up time indicated that they were not sources of heterogeneity.

CONCLUSIONS

An elevated RDW has the potential to be a biomarker for prognosis in PE patients.

Does Baseline BUN Have an Additive Effect on the Prediction of Mortality in Patients with Acute Pulmonary Embolism?

Background: In patients with heart failure, elevated levels of blood urea nitrogen (BUN) is a prognostic factor. In this study, we investigated the prognostic value of elevated baseline BUN in short-term mortality among patients with acute pulmonary embolism (PE). Methods: Between 2007 and 2014, cardiac biomarkers and BUN levels were measured in patients with acute PE. The primary endpoint was 30-day mortality, evaluated based on the baseline BUN (≥14 ng/L) level in 4 groups of patients according to the European Society of Cardiology's risk stratification (low-risk, intermediate low-risk, intermediate high-risk, and high-risk). Results: Our study recruited 492 patients with a diagnosis of acute PE (mean age=60.58±16.81 y). The overall 1-month mortality rate was 6.9% (34 patients). Elevated BUN levels were reported in 316 (64.2%) patients. A high simplified pulmonary embolism severity index (sPESI) score (OR: 5.23, 95% CI: 1.43-19.11; P=0.012), thrombolytic or thrombectomy therapy (OR: 2.42, 95% CI: 1.01-5.13; P=0.021), and elevated baseline BUN levels (OR: 1.04, 95% CI: 1.01-1.03; P=0.029) were the independent predictors of 30-day mortality. According to our receiver-operating characteristics analysis for 30-day mortality, a baseline BUN level of greater than 14.8 mg/dL was considered elevated. In the intermediate-low-risk patients, mortality occurred only in those with elevated baseline BUN levels (7.2% vs. 0; P=0.008). Conclusion: An elevated baseline BUN level in our patients with PE was an independent predictor of short-term mortality, especially among those in the intermediate-risk group.

A narrative review of red blood cell distribution width as a marker for pulmonary embolism

Red blood cell distribution width (RDW) is a marker of variability in red blood cell size, and is routinely reported as part of a patient's complete blood count. RDW has been shown to be associated with the prediction, severity and prognosis of pulmonary embolism (PE) in recent studies. The underlying biomolecular mechanism of the relationship of RDW to PE is largely unknown, but is thought to be due to the relationship of RDW with acute inflammatory markers and variations in blood viscosity. This review substantiates that a high RDW level, defined using either an arbitrary number or according to receiver operator curve statistics, is associated with a higher risk of acute PE, increased severity (massive vs. submassive) of PE and increased mortality in patients with PE. Nevertheless, the comparison of current studies is limited due to the definition of high RDW (each study uses a different RDW cutoff level), the broad range of exclusion criteria and the inclusion of differing modalities used to diagnose a PE (computed tomography angiogram, ventilation-perfusion study, or clinical diagnosis). Despite the above limitations, these studies provide a promising future clinical use for RDW as a marker of PE.

Elevated serum cardiac troponin and mortality in acute pulmonary embolism: Systematic review and meta-analysis

OBJECTIVES

To evaluate whether elevated levels of cardiac troponin increases the risk of mortality in patients with acute PE.

METHODS

We conducted a systematic review and meta-analysis with rigorous statistical evaluation using publications (2000-2018) from Cochrane Library, MEDLINE, PubMed, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), WHO International Clinical Trials Registry Platform, and Google Scholar databases. We searched for retrospective, prospective, and randomized controlled trials (RCT) or quasi-RCT studies that assessed the effect of elevated troponin versus normal levels on the outcomes of PE. The main outcome of interest was all-cause mortality. Extracted data included authors, the origin of studies, source population, study settings and duration, inclusion/exclusion criteria, data sources and measurement, sample size, and mortality. Data heterogeneity was assessed using the Cochrane Q homogeneity test with a significance set at p < 0.10. If the studies were statistically homogeneous, a fixed effect model was selected.

RESULTS

Out of 1825 references, 46 analytical studies were included with a total of 10842 patients with PE. The effect of elevated troponin on mortality had a pooled odd ratio (OR) of 4.33 for all studies, 3.7for HsTnT, 14.81 for HsTnI, 7.85 for cTnT, 2.81 for cTnI, 9.02 for low-risk PE and 4.80 for 90-day mortality. The pooled negative likelihood ratios for all-cause mortality using HsTnI, cTnI and cTnT assay were 0.21, 0.33 and 0.65, respectively.

CONCLUSION

Regardless of the troponin assay, pooled analysis indicates that elevated troponin is significantly associated with higher mortality in patients with PE.

A decision tree built with parameters obtained by computed tomographic pulmonary angiography is useful for predicting adverse outcomes in non-high-risk acute pulmonary embolism patients

Background

Acute pulmonary embolism (APE) is one of the leading causes of death in cardiovascular disease. The 30-day mortality can still be 1.7–15% in non-high-risk APE patients. Some non-high-risk patients can progress into the high-risk group and even die, which is referred to as an adverse outcome. Promoting the diagnosis and predictive ability of adverse short-term prognosis was still a problem that needed to be solved. Computed tomography pulmonary angiography (CTPA) may be a way to promote the predictive ability. Our aim to develop predictive tools based on parameters obtained by computed tomographic pulmonary angiography (CTPA) in the form of a decision tree for use in non-high-risk acute pulmonary embolism (APE) patients.

Methods

Adverse outcome was defined within 30 days after admission to the hospital. A decision tree was built to predict adverse outcomes based on discriminating factors screened from cardiac volume and clot characteristics from recursive partitioning analysis and compared with simplified pulmonary embolism severity index (sPESI), Bova scores and risk stratification. The area under the receiver operating characteristic curve (ROC-AUC) was used to confirm the predictive ability.

Results

A total of 38 patients with and 303 patients without adverse outcomes were enrolled. Right ventricular/left ventricular (RV/LV) volume ratio, central pulmonary artery (CPA) embolism and right atria/left atria (RA/LA) volume ratio were used as splits in the decision tree to predict adverse outcomes in all patients. The ROC-AUC was 0.858. In CPA embolism patients, a recursive partitioning analysis was performed with cardiac volume and novel clot burden, but only the obstructing area (OA) ratio was included as a discriminating factor to build a second decision tree. The ROC-AUC for the second decision tree was 0.810. The decision trees were superior to those of sPESI, Bova scores and risk stratification, and there were no significant differences between the two decision trees.

Conclusions

A decision tree built by CTPA parameters can predict adverse outcomes in non-high-risk APE patients.

Implications of elevated cardiac troponin in patients presenting with acute pulmonary embolism: an observational study

Background

To evaluate the implications of elevated cardiac troponin (cTn) in patients presenting with pulmonary embolism (PE).

Methods

We conducted a retrospective analysis for patients with PE between 2011 and 2015 with an average of 3 years follow-up. Patients were categorized into two groups based on the cTn status on admission (negative vs. positive) and RV/LV ratio (≤1.2 vs. >1.2). PE diagnosis was made by computed tomography pulmonary angiography (CTPA) examinations.

Results

Among 220 patients with PE, 52.7% had positive cTn and 31.7% had RV dysfunction. Protein S and C deficiency were significantly higher in patients with negative cTn. Patients with positive cTn were more likely to have high-risk simplified pulmonary embolism severity index (sPESI), RV dilation, RV/LV ratio >1.2, severe inferior vena cava reflux and high Qanadli score (QS >18 points). Thrombolytic therapy was used in 15 patients; 9 (60%) of them had elevated troponin. Combined cTn and sPESI had higher sensitivity, negative predictive value and negative likelihood ratio to predict in-hospital mortality. Overall 30-day and 3 years morality were 10.0% and 22.3%; that were significantly higher in patients with positive troponin. Cox regression analysis showed that mortality increased 2.5 times with positive cTn after adjusting for age, sex, and RV dysfunction (adjusted HR 2.5; 95% CI: 1.25-5.01), P=0.009.

Conclusions

Elevated cTn is independent predictor of short and long-term mortality. The predictive power of cTn increases when combined with the clinical probability score. Further, larger prospective studies are needed to confirm the findings of the present study.