Cellular Indices and Outcome in Patients with Acute Venous Thromboembolism

[Pulmonary Embolism]

Pulmonary embolism (PE), the most severe form of presentation of venous thromboembolic disease (VTE), currently represents a foremost healthcare issue due to its high impact in terms of morbidity, mortality, costs, and resource consumption. Early mortality associated with PE is primarily due to hemodynamic instability, exacerbation of pre-existing conditions, or major complications of antithrombotic therapies. Beyond the risk of death, there are relevant complications related to PE, such as bleedings, VTE recurrences, and persistence of residual respiratory symptoms; the latter complication related to PE is mainly characterized by two entities, chronic thromboembolic pulmonary hypertension and chronic thromboembolic disease. Significant scientific advances made in recent years have allowed for the improvement of both diagnostic and therapeutic management of the disease, as outlined in this document through a series of relevant issues about PE that are answered with the most up-to-date scientific evidence.

PROGNOSTICATION OF ACUTE PULMONARY EMBOLISM

Risk stratification of patients with acute pulmonary embolism (PE) assists with the selection of appropriate initial therapy and treatment setting. Patients with acute symptomatic PE that present with arterial hypotension or shock have a high risk of death, and treatment guidelines recommend strong consideration of reperfusion in this setting. For haemodynamically stable patients with PE, the combination of a negative clinical prognostic score and the absence of computed tomography-assessed right ventricle enlargement may accurately identify those at low-risk of short-term complications after the diagnosis of PE, and such patients might benefit from an abbreviated hospital stay or outpatient therapy. Some evidence suggests that the accumulation of factors indicating worse outcomes from PE on standard anticoagulation identifies the more severe stable patients with acute PE who might benefit from intensive monitoring and recanalization procedures, particularly if haemodynamic deterioration occurs. Current risk classifications have several shortcomings that might adversely affect clinical and healthcare decisions. Ongoing initiatives aim to address many of those shortcomings, and will hopefully help optimize risk stratification algorithms and treatment strategies.

The prognostic value of blood cellular indices in pulmonary embolism

Prognostication in acute pulmonary embolism (PE) requires reliable markers. While cellular indices such as neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII) appear promising, their utility in PE prognostication needs further exploration. We utilized data from the RIETE registry and the Loyola University Medical Center (LUMC) to assess the prognostic value of NLR, PLR, and SII in acute PE, using logistic regression models. The primary outcome was 30-day all-cause mortality. We compared their prognostic value versus the simplified Pulmonary Embolism Severity Index (sPESI) alone. We included 10 085 patients from RIETE and 700 from the LUMC. Thirty-day mortality rates were 4.6% and 8.3%, respectively. On multivariable analysis, an elevated NLR (>7.0) was associated with increased mortality (adjusted odds ratio [aOR]: 3.46; 95% CI: 2.60-4.60), outperforming the PLR > 220 (aOR: 2.36; 95% CI: 1.77-3.13), and SII > 1600 (aOR: 2.52; 95% CI: 1.90-3.33). The c-statistic for NLR in patients with low-risk PE was 0.78 (95% CI: 0.69-0.86). Respective numbers were 0.66 (95% CI: 0.63-0.69) and 0.68 (95% CI: 0.59-0.76) for intermediate-risk and high-risk patients. These findings were mirrored in the LUMC cohort. Among 9810 normotensive patients in RIETE, those scoring 0 points in sPESI and with an NLR ≤ 7.0 (35% of the population) displayed superior sensitivity (97.1%; 95% CI: 95.5-98.7) and negative predictive value (99.7%; 95% CI: 99.5-99.8) than sPESI alone (87.1%; 95% CI: 83.9-90.3, and 98.7%; 95% CI: 98.4-99.1, respectively) for 30-day mortality. The NLR is a significant prognostic marker for 30-day mortality in PE patients, especially useful to identify patients with very low-risk PE.

C-reactive Protein and Risk of Right Ventricular Dysfunction and Mortality in Patients With Acute Symptomatic Pulmonary Embolism

BACKGROUND

Right ventricle (RV) dysfunction increases the risk of death from pulmonary embolism (PE). C-reactive protein (CRP) might identify RV inflammation and dysfunction in patients with PE.

METHODS

This cohort study enrolled consecutive stable patients with acute PE between 2017 and 2023. We stratified patients by quartiles of CRP. We evaluated the association between CRP quartiles and the presence of RV dysfunction, and used multivariable models to assess for an association between CRP and the outcomes of all-cause and PE-specific mortality during the 30 days of follow-up after PE diagnosis.

RESULTS

The study included 633 stable patients with PE. Patients without RV dysfunction had significantly lower median (IQR) CRP levels compared with patients with RV dysfunction (n=509, 31.7 [10.0-76.4]mg/L vs n=124, 45.4 [16.0-111.4]mg/L; P=0.018). CRP showed a statistically significant positive association with the presence of RV dysfunction (P<0.01). On multivariable analysis, CRP level was not significantly associated with 30-day all-cause mortality (adjusted odds ratio [OR] per mg/L increment, 1.00; 95% CI, 1.00-1.01; P=0.095), but higher CRP was associated with significantly higher PE-related mortality (adjusted OR, 1.01; 95% CI, 1.00-1.01; P=0.026). Compared with patients in CRP quartile 1, patients in quartiles 2, 3, and 4 had a stepwise increase in the adjusted odds of 30-day all-cause death of 2.41 (P=0.148), 3.04 (P=0.062), and 3.15 (P=0.052), respectively.

CONCLUSIONS

As an indicator of RV dysfunction, CRP may improve risk stratification algorithms for hemodynamically stable patients with acute symptomatic PE.

Decreased Thrombin Generation is Associated with Increased Thrombin Generation Biomarkers and Blood Cellular Indices in Pulmonary Embolism

Pulmonary embolism (PE) is a heterogenous condition with variable clinical presentations. Thrombin generation potential (TGP) and biomarkers, and blood cellular indices can reflect the underlying pathophysiology and risk stratification of PE. This case-control study analyzed TGP in 209 PE patients from Loyola University, Pulmonary Embolism Response Team program compared to normal human plasma (NHP) controls. The present study evaluates TGP and biomarkers, and cellular indices in relation to PE severity, according to the European Society of Cardiology (ESC) guidelines. Statistical analysis including median with interquartile range (IQR), 2-tailed Wilcoxon Mann-Whitney test, Chi-square test, and Spearman Correlational analysis were performed. There were 209 patients with PE, with an almost equal distribution between sex, and a median age of 63 years. Significant downregulation in peak thrombin and endogenous thrombin potential (ETP), as well as upregulation in lag time, were observed in PE patients versus controls. Biomarker analysis revealed pronounced elevations, with D-dimer demonstrating the most significant increase. Blood cellular indices also rose in PE patients, correlating with disease severity. PE severity was associated with higher TGP and biomarker levels. Mortality rates differed significantly across risk categories and were highest in patients with elevated cellular indices. TGP and biomarkers are intricately linked to PE severity and can aid in risk stratification. Elevated cellular indices are associated with increased mortality, highlighting their potential as prognostic markers. These findings could enhance the precision of PE management strategies.

Association between diabetes and venous thromboembolism: A systematic review and meta-analysis

BACKGROUND

Diabetes mellitus (DM) plays a vital role in the development of cardiovascular disease. However, its association with venous thromboembolism (VTE) remains unclear, for the published study results are conflicting. We performed a meta-analysis of published cohort studies and case-control studies to assess the role of DM in the formation and prognosis of VTE.

METHODS

PubMed and EMBASE databases were searched for articles from the database's establishment until September 15, 2022. Of the 15,754 publications retrieved, 50 studies were identified that met the selection criteria. The New castle-Ottawa Scale was used to evaluate the quality of the literature. Pooled odds ratios (ORs) and 95% confidence intervals were calculated using fixed- or random-effect models.

RESULTS

We combined OR using a random-effects or fixed-effects model: patients with DM had an increased risk of VTE (OR 1.27, 95% confidence interval [CI]: 1.15-1.41), which still showed a partial association in studies adjusted by confounding factors (OR 1.20, 95% CI: 1.07-1.35). DM was not significantly associated with VTE when analyzed in studies adjusted by body mass index (OR 1.04, 95% CI: 0.94-1.15). VTE patients with DM had a higher risk of short-term and long-term mortality than those without DM (OR 1.58 [95% CI: 1.26-1.99] for long-term mortality and OR 1.20 [95% CI: 1.19-1.21] for short-term mortality).

CONCLUSION

There was no significant association between DM and VTE risk, and body mass index may be a significant confounding factor between DM and VTE risk. However, DM can still lead to an increased risk of long-term and short-term mortality in patients with VTE.

The Diagnostic Value of the Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio for Deep Venous Thrombosis: A Systematic Review and Meta-Analysis

The neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are emerging tools that can be used in the diagnosis of deep venous thrombosis (DVT). This study aims to evaluate the diagnostic value of NLR and PLR for patients with DVT. Our meta-analysis included 11 eligible studies and extracted relevant diagnostic indicators. Of these studies, 4 focused on the NLR, 1 on the PLR, while 6 evaluated both. For the 10 studies on NLR, the pooled sensitivity, specificity, positive-likelihood ratio, and negative-likelihood ratio were 74%, 66%, 2.16, and 0.4, respectively. The estimated diagnostic odds ratio (DOR) was 5.3, and the area under the curve (AUC) of the summary receiver operating characteristic (SROC) curves was 0.74. For the 7 studies on the PLR, the pooled sensitivity, specificity, positive-likelihood ratio, and negative-likelihood ratio were 0.65, 0.77, 2.89, and 0.45, respectively. The estimated DOR was 6.64, and the SROC-AUC was 0.79. Our findings showed that the NLR and PLR exhibit moderate diagnostic accuracy and may be helpful biomarkers for the diagnosis of DVT. Future prospective, well-designed studies with large sample sizes will be required to provide additional evidence to establish cutoff values and clinical value of these indicators.

The Association of Neutrophil-Lymphocyte Ratio with Venous Thromboembolism: A Systematic Review and Meta-Analysis

The neutrophil–lymphocyte ratio(NLR) has been used for diagnosing venous thromboembolism (VTE). We aimed to assess the accuracy of NLR to diagnose VTE by meta-analysis. Systematic electronic searches were conducted June 2, 2021 in PubMed, Embase(Ovid), and Cochrane Library. The search did not have any language or time restriction applied. Our search strategy was based on keywords in combination with both medical subject headings (MeSH) terms and text words. The diagnostic odds ratio, summary receiver operating characteristics, sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio were estimated. 10 articles with 1513 VTE participants and 2593 control participants were included for quantitative synthesis. The pooled values were as follows: sensitivity = 0.68(95% CI 0.45-0.84), specificity = 0.73(95% CI 0.6-0.83), positive likelihood ratio = 2.5(95% CI 1.8-3.4), negative likelihood ratio = 0.44(95% CI 0.26-0.75), diagnostic odds ratio = 6(95% CI 3-11), and SROC = 0.76(95% CI: 0.73-0.8). NLR could be diagnostic factor for the detection of potential VTE, the accuracy thereof in the current meta-analysis exhibited moderate accuracy for diagnosing VTE. Furthermore, further large cohort studies are needed to determine optimal cut-off values of NLR.