Venous thromboembolism: epidemiology and magnitude of the problem

Diagnostic value of D-dimer to fibrinogen ratio for pulmonary embolism in postpartum women

BACKGROUND

Pulmonary embolism is a common disease associated with high mortality and morbidity. Diagnosing pulmonary embolism is challenging due to diverse clinical presentations and the lack of specific biomarkers. The study aimed to investigate the diagnostic value on pulmonary embolism for postpartum women by D-dimer to fibrinogen ratio, and it combined with neutrophil-to-lymphocyte ratio or platelet-to-lymphocyte ratio.

METHODS

A total of 537 women with suspected pulmonary embolism were selected as the research subjects from the Shanghai First Maternity and Infant Hospital between 1 January 2019 and 31 October 2022. The D-dimer to fibrinogen ratio and it combined with neutrophil-to-lymphocyte ratio or platelet-to-lymphocyte ratio were applied to evaluate the clinical probability of pulmonary embolism, and the positive predictive value of both scores were calculated using computed tomography pulmonary arteriography as a gold standard. The diagnostic value of D-dimer to fibrinogen ratio, combined with neutrophil-to-lymphocyte ratio or platelet-to-lymphocyte ratio was evaluated by the area under the curve, sensitivity, specificity, and other indicators in the receiver operator characteristic curve.

RESULTS

Among the 502 women included for analysis, 194 (38.65%) were definitely diagnosed as pulmonary embolism. The positive predictive values of D-dimer to fibrinogen ratio and it combined with platelet-to-lymphocyte ratio or neutrophil-to-lymphocyte ratio were 70.1%, 50.5%, and 56.5%, respectively in the postpartum women, the area under the curve for the D-dimer to fibrinogen ratio and it combined with platelet-to-lymphocyte ratio or neutrophil-to-lymphocyte ratio were 0.606 (95%CI: 0.562-0.650), 0.624 (95%CI: 0.575-0.673), and 0.639 (95%CI: 0.592-0.686), respectively. The negative predictive values of D-dimer to fibrinogen ratio, it combined with platelet-to-lymphocyte ratio or neutrophil-to-lymphocyte ratio were 50.5%, 70.1%, and 69.8%, respectively.

CONCLUSION

The diagnostic value of the D-dimer to fibrinogen ratio was higher than the D-dimer for the postpartum women with suspected pulmonary embolism. The combination of either the neutrophil-to-lymphocyte ratio or the platelet-to-lymphocyte ratio with D-dimer to fibrinogen ratio is an appropriate strategy to rule out pulmonary embolism.

A meta-analysis of outcomes of aspiration thrombectomy for high and intermediate-risk pulmonary embolism

BACKGROUND

Aspiration thrombectomy has gained popularity in patients with massive and sub-massive pulmonary embolism (PE) and having contraindications to thrombolysis.

METHODS

A meta-analysis was conducted including studies on aspiration thrombectomy in patients with high-risk and intermediate-risk PE. The pooled odds ratio for efficacy parameters, including change in heart rate, blood pressure and right ventricle/left ventricle (RV/LV) ratio, and safety parameters including major bleeding and stroke, was calculated using a random effects model.

RESULTS

The meta-analysis of 24 selected studies revealed that intermediate and high-risk pulmonary embolism (PE) patients demonstrated significant improvements: modified Miller score odds ratio of 10.60, mean pulmonary artery pressure reduction by 0.04 mm Hg, and an overall all-cause mortality odds ratio of 0.10. Considerable heterogeneity was observed in various outcomes.

CONCLUSION

Aspiration thrombectomy has success rates in both high-risk and intermediate-risk PE, however, procedural risks, including bleeding, must be anticipated.

Thromboembolic Disease

Venous thromboembolism (VTE) encompasses deep vein thrombosis and pulmonary embolism, both of which can present on a spectrum from subtle symptoms to life- and limb-threatening emergencies. Some risk factors for VTE overlap cardiovascular risk factors and statin therapy can somewhat reduce the VTE risk. When presentations are not life-threatening, clinical prediction scores using the Well's criteria are best used to determine diagnostic testing. The mainstay of VTE treatment is anticoagulant therapy, although life- and limb-threatening presentations can also require thrombolytic therapy.

Shock score for prediction of clinical outcomes among stable patients with acute symptomatic pulmonary embolism

BACKGROUND

The Composite Pulmonary Embolism Shock (CPES) score has been developed to identify normotensive patients with acute pulmonary embolism (PE) and a low cardiac index (referred to as normotensive shock). We aimed to externally assess the validity of this model for predicting a complicated course among hemodynamically stable patients with acute PE.

METHODS

Using prospectively collected data from the PROgnosTic valuE of Computed Tomography scan (PROTECT) study, we calculated the CPES score for each patient and the proportion of patients with a score > 3. We calculated the test performance characteristics to predict a complicated course (i.e., death from any cause, hemodynamic collapse, or recurrent PE) and the discriminatory power using the area under the receiver operating characteristic curve.

RESULTS

Sixty-three of the 848 (7.4 %) patients had a complicated course during the 30-day follow-up period. Of the 848 enrolled patients, the CPES score was positive (i.e., score > 3) in 78 (9.2 %). The specificity was 92.1 % (723/785), the positive predictive value was 20.5 % (16/78), and the positive likelihood ratio was 3.22 for a complicated course. The areas under the receiver operating characteristic curve for a complicated course were 0.71 (95 % confidence interval [CI], 0.65-0.78). With the higher score risk classification threshold (cutoff score > 4), the proportion of patients designated as positive was 2.1 %, and the specificity was 98.1 %. When echocardiographic right ventricle (RV) dysfunction was replaced by computed tomographic RV enlargement, the specificity was 85.4 %, the positive predictive value was 14.2 %, and the positive likelihood ratio was 2.06 for a complicated course. When analyses were restricted to the subgroup of patients with intermediate-risk PE, the specificity and the positive predictive value for a complicated course were identical to the overall cohort.

CONCLUSIONS

The CPES score has acceptable C-statistic, excellent specificity, and low positive predictive value for identification of hemodynamic deterioration in normotensive patients with PE.

CLINICALTRIALS

gov number: NCT02238639.

Short- and Long-Term Mortality for Patients With and Without a Cancer Diagnosis Following Pulmonary Embolism in Denmark, 2000 to 2020: A Nationwide Study

BACKGROUND

New treatment regimens have been introduced in the past 20 years, which may influence the short- and long-term prognosis for patients with and without a cancer diagnosis following pulmonary embolism. However, newer studies investigating these trends are lacking. Therefore, we aimed to investigate the 30- and 31- to 365-day mortality following pulmonary embolism.

METHODS AND RESULTS

Using the Danish nationwide registries, patients with a diagnosis of pulmonary embolism between 2000 and 2020 were included. Age- and sex-standardized 30- and 31- to 365-day mortality was calculated and stratified by cancer status. In total, 60 614 patients (29.6% with recent cancer; mean age, 68.2 years) were included. The 30-day mortality for patients with no recent cancer decreased from 19.1% (95% CI, 17.9%-20.4%) in 2000 to 7.3% (95% CI, 6.7%-8.0%) in 2018 to 2020 (hazard ratio [HR], 0.36 [95% CI, 0.32-0.40]; P<0.001). The 30-day mortality for patients with recent cancer decreased from 32.2% (95% CI, 28.8%-36.6%) to 14.1% (95% CI, 12.7%-15.5%) (HR, 0.38 [95% CI, 0.33-0.44]; P<0.001). The 31- to 365-day mortality for patients with no recent cancer decreased from 12.5% (95% CI, 11.4%-13.6%) to 9.4% (95% CI, 8.6%-10.2%) (HR, 0.73 [95% CI, 0.64-0.83]; P<0.001).The 31- to 365-day mortality for patients with recent cancer remained stable: 39.4% (95% CI, 35.1%-43.7%) to 38.3% (95% CI, 35.9%-40.6%) (HR, 0.97 [95% CI, 0.84-1.12]; P=0.69).

CONCLUSIONS

From 2000 to 2020, improvements were observed in 30-day mortality following pulmonary embolism regardless of cancer status. For patients with recent cancer, 31- to 365-day mortality did not improve, whereas a minor improvement was observed for patients without recent cancer.

Arterial and Venous Thromboembolic Complications in 832 Patients with BCR-ABL-Negative Myeloproliferative Neoplasms

Arterial (ATE) and venous (VTE) thromboembolic complications are common causes of morbidity and mortality in BCR-ABL-negative myeloproliferative neoplasms (MPNs). However, there are few studies that include all MPN subtypes and focus on both MPN-associated ATE and VTE. In our single-center retrospective study of 832 MPN patients, a total of 180 first thromboembolic events occurred during a median follow-up of 6.6 years (range: 0-37.6 years), of which 105 were VTE and 75 were ATE. The probability of a vascular event at the end of the follow-up period was 36.2%, and the incidence rate for all first ATE/VTE was 2.43% patient/year. The most frequent VTE localizations were deep vein thrombosis with or without pulmonary embolism (incidence rate: 0.59% patient/year), while strokes were the most frequent ATE with an incidence rate of 0.32% patient/year. When comparing the group of patients with ATE/VTE (n = 180) and the group without such an event (n = 652) using multivariate Cox regression analyses, patients with polycythemia vera (hazard ratio [HR]: 1.660; [95% confidence interval [CI] 1.206, 2.286]) had a significantly higher risk of a thromboembolic event than the other MPN subtypes. In contrast, patients with a CALR mutation had a significantly lower risk of thromboembolism compared with JAK2-mutated MPN patients (HR: 0.346; [95% CI: 0.172, 0.699]). In summary, a high incidence of MPN-associated VTE and ATE was observed in our retrospective study. While PV patients or generally JAK2-mutated MPN patients had a significantly increased risk of such vascular events, this risk was reduced in CALR-mutated MPN patients.

Efficacy and safety of vena cava filters in preventing pulmonary embolism: A systematic review and meta-analysis

OBJECTIVES

To assess the treatment effectiveness of inferior vena cava filters (IVCF) versus non-IVCF for patients undergoing varies conditions.

METHODS

We systematically searched the databases to identify eligible RCTs from their inception up to 9/20/2020. The primary endpoint was pulmonary embolism (PE), while the secondary endpoints included deep-vein thrombosis (DVT), major bleeding, and all-cause mortality. The RRs with 95% CIs were applied as effect estimates for the treatment effectiveness of IVCF versus non-IVCF and calculated by using the random-effects model.

RESULTS

1,137 patients of 5 RCTs were enrolled. There were no significant differences between IVCF and non-IVCF for the risk of PE, major bleeding, and all-cause mortality, while the risk of DVT was significantly increased for patients treated with IVCF.

CONCLUSIONS

The use of IVCF did not yield any benefits on PE, major bleeding, and all-cause mortality risk for patients undergoing various conditions, while the risk of DVT was significantly increased for patients treated with IVCF.

Venous thromboembolism: Why is it still a significant health problem?

BACKGROUND

Venous thromboembolism (VTE) remains the third leading cause of acute cardiovascular syndrome following myocardial infarction and ischemic stroke. The global burden of disease worldwide is high and shows a steady upward trend in recent years with an incidence of 1-2 per 1000 adults per year. The overarching goal of the initial management of VTE is to prevent early and late adverse outcomes. Rapid evaluation and therapeutic intervention is vital to improving prognosis.

METHODS

We searched PubMed, Science Direct and Scopus databases for articles published in the last 10 years. Additionally, some earlier articles were analyzed.

RESULTS

For the purposes of this review, we discussed how understanding the epidemiology of VTE and the current knowledge of early and late complications of this disease have shaped the current approach to VTE prevention. We also analyzed the current knowledge and the most up-to-date information about VTE in COVID-19 infection. Contemporary perspective presented in this article on mortality in VTE, the incidence of recurrences, the risk of major bleeding during therapy and the chronic complications indicate why this is a major challenge for today's medicine and a current target for further research.

CONCLUSIONS

Understanding the interaction between environmental and genetic factors appears to be crucial in the diagnostic process. It can provide insight into the pathophysiology of VTE, potentially identifying options for targeted prevention and treatment. However, due to differences in clinical presentation, diagnosing pulmonary embolism may not be an easy task which perfectly illustrates the scale and complexity of the disease.

Independent risk factors for an increased incidence of thromboembolism after lung transplantation

BACKGROUND

Thromboembolism (TE) after lung transplantation (LTX) is associated with increased morbidity and mortality. The aim of this study is to analyze the incidence and outcome of venous and arterial thromboembolic complications and to identify independent risk factors.

PATIENTS AND METHODS

We retrospectively analyzed the medical records of 221 patients who underwent LTX at our institution between 2002 and 2021. Statistical analysis was performed using SPSS and GraphPad software.

RESULTS

74 LTX recipients (33%) developed TE. The 30-days incidence and 12-months incidence were 12% and 23%, respectively. Nearly half of the patients (48%) developed pulmonary embolism, 10% ischemic stroke. Arterial hypertension (p = 0.006), a body mass index (BMI) > 30 (p = 0.006) and diabetes mellitus (p = 0.041) were independent predictors for TE. Moreover, a BMI of > 25 at the time of transplantation was associated with an increased risk for TE (43% vs. 32%, p = 0.035). At the time of LTX, 65% of the patients were older than 55 years. An age > 55 years also correlated with the incidence of TE (p = 0.037) and these patients had reduced overall post-transplant survival when the event occurred within the first postoperative year (59% vs. 72%, p = 0.028).

CONCLUSIONS

The incidence of TE after LTX is high, especially in lung transplant recipients with a BMI > 25 and an age > 55 years as well as cardiovascular risk factors closely associated with the metabolic syndrome. As these patients comprise a growing recipient fraction, intensified research should focus on the risks and benefits of regular screening or a prolonged TE prophylaxis in these patients. Trial registration number DKRS: 00021501.

Risk adjusted venous thromboembolism prophylaxis following pancreatic surgery

This study analyzes pancreatectomy cases performed between 2016 and 2021 to determine the impact of using Caprini guideline indicated VTE prophylaxis on VTE and bleeding complications. This is a retrospective study of cases performed in a single academic health care system, in which Caprini score and VTE prevention measures were determined retroactively and prevention practices binarized as appropriate or not appropriate. Univariate and multivariate analyses were performed of 1,299 pancreatectomy case. Most patients were stratified as high risk for postoperative VTE. Receiving appropriate VTE prophylaxis during admission was associated with a 3-fold reduction in VTE complications (0.82% vs. 2.64%, p=0.01) without increasing bleeding complications. All VTE complications occurring with 30-day (1.2%) and 90-day (2.7%) from hospital discharged occurred in those not receiving appropriate prophylaxis, and discharged bleeding complications were also not associated with receivng appropriate discharged VTE prophylaxis. The findings our the study are significant as it highlights the ongoing need for standardization in VTE risk assessment and prevention measures to increase compliance to risk adjusted VTE prevention practice guidelines, thus reducing preventable VTE complications and potentially associated morbidity and mortality.

The Saudi Consensus for the Management of Cancer-Associated Thromboembolism: A Modified Delphi-Based Study

Background  Cancer is a well-known risk factor of preventable thromboembolic disease. This study aims to provide guidance on the prevention and management of cancer-associated thrombosis (CT) that tailors prophylactic and therapeutic options for medical and surgical oncology patients presenting to health care settings in Saudi Arabia. Methods  The present consensus was developed in concordance with the modified Delphi-based approach, which incorporates a face-to-face meeting between two voting rounds to gain experts' feedback on the proposed statements. All experts were either oncologists, hematologists, or hemato-oncologist with an active clinical and research profile in hemato-oncology. Results  The experts highlighted that the comparatively high incidence of inherited thrombophilia among the Saudi population may account for a higher CT burden in the Kingdom than in other parts of the world. However, due to the lack of literature that assesses CT in Saudi Arabia, primary venous thromboembolism prophylaxis should be tailored according to a valid risk assessment of cancer patients and should be implemented in routine practice. For hospitalized medical oncology patients, the experts agreed that prophylaxis with low-molecular-weight heparin (LMWH) should be offered, regardless of the presence of acute illness. For ambulatory medical oncology patients, LMWH or direct oral anticoagulants (DOACs) prophylaxis should be offered for high-risk patients. Concerning surgical patients, they agreed that all oncology patients undergoing surgery should be offered thromboprophylaxis. In terms of secondary prophylaxis, the experts recommended continuing a prophylactic dose of anticoagulant (LMWH or DOAC), for an appropriate period depending on the cancer type and stage. Finally, they also provided a set of statements on management of CT in Saudi Arabia. Conclusion  The present modified Delphi-based study combined the best available evidence and clinical experience with the current health care policies and settings in Saudi Arabia to build a consensus statement on the epidemiology, prevention, and management of CT.

Association Between Red Blood Cell Indices and Preoperative Deep Vein Thrombosis in Patients Undergoing Total Joint Arthroplasty: A Retrospective Study

PURPOSE

To investigate the association of red blood cell (RBC), hemoglobin (Hb), red cell distribution width-coefficient of variation (RDW-CV), and red cell distribution width-standard deviation (RDW-SD) with preoperative deep vein thrombosis (DVT) in patients undergoing total joint arthroplasty (TJA).

METHODS

A total of 2059 TJA patients were enrolled. We used the ratios of RBC, Hb, RDW-CV, and RDW-SD to DVT before TJA to create the receiver operator characteristic (ROC) curve, thereby calculating the cut-off values and the area under the curve (AUC). The patients were categorized into groups based on cut-off value, and risk factors for DVT before TJA were subsequently analyzed. We included the variates that were statistically significant in the univariate analysis in the multivariate binary logistic regression analysis.

RESULTS

Preoperative DVT occurred in 107 cases (5.20%). Based on the ROC curve, we found that the AUC for RBC, Hb, RDW-CV, and RDW-SD were 0.658, 0.646, 0.568, and 0.586, respectively. Multivariate binary regression analysis revealed that the risk of preoperative DVT in TJA patients with RBC≤3.92*10⁹ /L, Hb≤118g/L, RDW-CV≥13.2%, and RDW-SD≥44.6fL increased 3.02 (P < 0.001, 95% confidence interval (CI) [2.0-4.54]), 2.15 (P < 0.001, 95% CI [1.42-3.24]), 1.54 (P = 0.038, 95% CI [1.03-2.3]), and 1.98 times (P = 0.001, 95% CI [1.32-2.98]), respectively. The risk of preoperative DVT in patients with corticosteroid use increased approximately 2.6 times (P = 0.002, 95% CI [1.22-5.81]).

CONCLUSION

We found that decreased RBC and Hb, increased RDW-CV and RDW-SD, and corticosteroid use were independent risk factors for preoperative DVT in patients undergoing TJA.

Antiplatelet agents for the treatment of deep venous thrombosis

BACKGROUND

Antiplatelet agents may be useful for the treatment of deep venous thrombosis (DVT) when used in addition to best medical practice (BMP), which includes anticoagulation, compression stockings, and clinical care such as physical exercise, skin hydration, etc. Antiplatelet agents could minimise complications such as post-thrombotic syndrome (PTS) and pulmonary embolism (PE). They may also reduce the recurrence of the disease (recurrent venous thromboembolism (recurrent VTE)). However, antiplatelet agents may increase the likelihood of bleeding events.

OBJECTIVES

To assess the effects of antiplatelet agents in addition to current BMP compared to current BMP (with or without placebo) for the treatment of DVT.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 7 December 2021. The review authors searched LILACS and IBECS databases (15 December 2021) and also checked the bibliographies of included trials for further references to relevant trials, and contacted specialists in the field, manufacturers and authors of the included trials.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) examining antiplatelet agents compared to BMP following initial standard anticoagulation treatment for DVT. We included studies where antiplatelet agents were given in addition to current BMP compared to current BMP (with or without placebo) for the treatment of DVT (acute: treatment started within 21 days of symptom onset; chronic: treatment started after 21 days of symptom onset). We evaluated only RCTs where the antiplatelet agents were the unique difference between the groups (intervention and control).

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. Two review authors independently extracted data and assessed risk of bias of the trials. Any disagreements were resolved by discussion with a third review author. We calculated outcome effects using risk ratio (RR) or mean difference (MD) with a 95% confidence interval (CI) and the number needed to treat to benefit (NNTB).

MAIN RESULTS

We included six studies with 1625 eligible participants, with data up to 37.2 months of follow-up. For one preplanned comparison (i.e. antiplatelet agents plus BMP versus BMP plus placebo) for acute DVT we identified no eligible studies for inclusion. In acute DVT, antiplatelet agents plus BMP versus BMP alone was assessed by one study (500 participants), which reported on four outcomes until 6 months of follow-up. There were no deaths and no cases of major bleeding reported. The participants who received antiplatelet agents showed a lower risk of PTS (RR 0.74, 95% CI 0.61 to 0.91; 1 study, 500 participants; very low-certainty evidence). The control group presented a lower risk of adverse events compared to the intervention group (RR 2.88, 95% CI 1.06 to 7.80; 1 study, 500 participants; very low-certainty evidence). This study did not provide information for recurrent VTE or PE. In chronic DVT, antiplatelet agents plus BMP versus BMP alone was assessed by one study (224 participants). The study authors reported four relevant outcomes, three of which (major bleeding, mortality and adverse events) showed no events during the 3 years of follow-up. Therefore, an effect estimate could only be reported for recurrent VTE, favouring antiplatelet agents plus BMP versus BMP alone (RR 0.12, 95% CI 0.05 to 0.34; 1 study, 224 participants; very low-certainty evidence). For the outcomes PE and PTS, this study did not present information which could be used for analysis. In chronic DVT, antiplatelet agents plus BMP versus BMP plus placebo was assessed by four studies (901 participants). The meta-analysis of this pooled data showed a lower risk of recurrent VTE for the antiplatelet agents group (RR 0.65, 95%, CI 0.43 to 0.96; NNTB = 14; low-certainty evidence). For major bleeding, we found no clear difference between placebo and intervention groups until 37.2 months of follow-up (RR 0.98, 95% CI 0.29 to 3.34; 1 study, 583 participants; moderate-certainty evidence). In PE fatal/non-fatal outcome, we found no clear difference with the use of antiplatelet agents (RR 0.52, 95% CI 0.23 to 1.14; 1 study, 583 participants; moderate-certainty evidence). For all-cause mortality, the overall effect of antiplatelet agents did not differ from the placebo group (RR 0.48, 95% CI 0.21 to 1.06; 3 studies, 649 participants; moderate-certainty evidence). The adverse events outcome did not show a clear difference (RR 1.57, 95% CI 0.34 to 7.19; 2 studies, 621 participants; moderate-certainty evidence). There is no assessment of PTS in these studies. We downgraded the certainty of evidence for risk of bias, indirectness, imprecision and publication bias.

AUTHORS' CONCLUSIONS

In chronic DVT settings, following the initial standard treatment with anticoagulants, there is low-certainty evidence that antiplatelet agents in addition to BMP may reduce recurrent VTE, (NNTB = 14) when compared to BMP plus placebo. Moderate-certainty evidence shows no clear difference in adverse events, major bleeding and PE when antiplatelet agents are used in addition to BMP compared to BMP plus placebo. In acute and chronic DVT settings, following the initial standard treatment with anticoagulants, we can draw no conclusions for antiplatelet agents in addition to BMP compared to BMP alone due to very low-certainty evidence.  Trials of high methodological quality, that are large and of sufficient duration to detect significant clinical outcomes are needed. Trials should ideally last more than 4 years in order to estimate the long-term effect of antiplatelet agents. Trials should include people with acute and chronic DVT and provide relevant individual data, such as the outcome for each index event (DVT or PE), the use of an inferior vena cava (IVC) filter, whether the DVT is provoked or unprovoked, and the age of participants.

Current use of D-dimer for the exclusion of venous thrombosis in hospitalized patients

D-dimer assay’s utility for excluding venous thromboembolism (VTE) in hospitalized patients is debatable. We aimed to assess the current use of D-dimer as a diagnostic tool for excluding VTE in hospitalized patients and examine a mandatory age-adjusted D-dimer (AADD) threshold for diagnostic imaging. Retrospective cohort study between 2014 to 2019 that included patients from medical and surgical wards with a positive AADD result drawn during their hospitalization. The outcomes were determining a D-dimer threshold requiring further evaluation and assessing the prognostic value of D-dimer in predicting clinically relevant VTE in hospitalized patients. The cohort included 354 patients, 56% of them underwent definitive diagnostic imaging, and 7.6% were diagnosed with VTE after a positive AADD within 90 days of follow-up. Mortality rates were higher in patients diagnosed with VTE (33.3% vs. 15.9%, p = 0.03). Patients with pneumonia and other infectious etiologies were less likely to be further evaluated by definitive imaging (p = 0.001). Patients with a respiratory complaint (p = 0.02), chest pain (p < 0.001), or leg swelling (p = 0.01) were more likely to undergo diagnostic imaging. Patients with D-dimer levels > X2 the AADD were at increased risk of VTE [OR 3.87 (1.45–10.27)]. At 90 days of follow-up, no excess mortality was observed for patients without diagnostic evaluation following elevated AADD. D-dimer may be used in hospitalized patients to exclude VTE using the traditional AADD thresholds, with a high negative predictive value. D-dimer levels > X2 the AADD usually mandates further diagnostic imaging, while lower levels, probably do not require additional workup, with a sensitivity of almost 80% and no excess mortality.

Dual-target synergistic antithrombotic mechanism of a Dabigatran etexilate analogue (HY023016)

Thrombin has long been considered a desirable antithrombotic target, but anti-thrombin therapy without anti-platelet therapy has never achieved the ideal effect. HY023016, derived from dabigatran etexilate, exhibited a potent antithrombotic efficacy. In the present study, mechanisms underlying this effect were explored. HY023016 strongly decreased the binding of thrombin to recombinant GPIbα N-terminal sequence which was confirmed by surface plasmon resonance. Flow cytometry revealed that HY023016 selectively decreased the binding of antibody to GPIbα and inhibited the washed human platelet aggregation induced by thrombin. Fluorescence experiment showed that HY023016 remarkably inhibited exosite II by a loss of affinity for the γ'-peptide of fibrinogen. Using intravital microscopy, we observed and recorded the dynamic process of thrombus formation and found that HY023016 effectively prevented thrombus formation in rat arteriovenous shunt thrombosis model. On the basis of these findings, we propose that HY023016 provides a novel insight into the antithrombotic mechanism, which exerts synergistic anticoagulant and antiplatelet effects through thrombin and GPIbα.

Extracellular Vesicles Derived from 3T3-L1 Adipocytes Enhance Procoagulant Activity

Obesity is associated with the risk of venous thromboembolism. Thrombi are constantly formed via the coagulation cascade and degraded by the fibrinolytic system, so they tend to form in obese individuals. Adipocytes are involved in thrombus formation in obesity, but it is not clear whether bioactive factors from adipocytes directly initiate or enhance coagulation and thrombosis. In this study, we confirmed that adipocyte-derived extracellular vesicles (ADEVs) enhance procoagulant activity in vitro. ADEVs prepared from the culture supernatant of mature 3T3-L1 adipocytes shortened plasma clotting times. Moreover, the effect of ADEVs on clotting time was weakened when using plasma lacking factors of the extrinsic pathway, but not the intrinsic pathway. ADEVs contain tissue factors and phosphatidylserine, which are involved in the extrinsic pathway, and blockade of these molecules diminished the effects of ADEVs on plasma clotting time. Additionally, the effect of ADEVs on plasma clotting time was further enhanced when cells were stimulated with the proinflammatory cytokine tumor necrosis factor-α. Thus, ADEVs may be a factor in thrombus formation in obesity.

State-of-Art in the Age Determination of Venous Thromboembolism: A Systematic Review

Venous thromboembolism (VTE), consisting of deep vein thrombosis (DVT) and pulmonary embolism (PE), requires a forensic age determination to ascertain their causal relationship with recent events, such as trauma or medical treatment. The main objective of this systematic review is to identify the current state-of-the-art immunohistochemical methods for age determination of fatal VTE. A literature search was performed through different databases, according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Within the study, we have selected only cases represented by deceased patients for DVT and/or PTE in which thromboembolic material was collected during an autoptic examination and then subjected to a histological and an immunohistochemical investigation. Studies based on animal models were not included. We assessed bias risk. A database-based search produced a total of 19 articles. After excluding duplicate items from the selection, 14 articles were reviewed. Ten articles were excluded because they did not meet the inclusion criteria. The results have pointed out 4 studies that were included in the present analysis for a total of 157 samples of DVT and 171 PTE samples. These were analyzed using traditional histological and immunohistochemical techniques. The results must be interpreted with a critical eye because of their heterogeneity in terms of time, geography, and study design. The present review highlights the importance of associating specific immunohistochemical markers with a histological analysis for the timing of DVT/PTE fatal events. Further future experiences will hopefully endorse actual knowledge on the subject to increase the accuracy in the assessment of thrombus-embolus age.

Prevention of venous thromboembolism in hematologic neoplasms: an expert consensus from SEHH-SETH

Venous thromboembolism (VTE) is a serious complication in hematologic neoplasms, so finding adequate prevention strategies is an urgent requirement. However, prospective studies with large enough cohorts are scarce, limiting the development of evidence-based thromboprophylaxis guidelines. The present position paper is addressed to all hematologists treating patients affected by hematologic neoplasms with the aim to provide clinicians with a useful tool for the prevention of VTE.

Incidence, timing and risk factors of venous thromboembolic events in patients with pancreatic cancer

INTRODUCTION

Pancreatic cancer is associated with a high risk of venous thromboembolism (VTE). However, comprehensive data on incidence, timing and relevant determinants of VTE in this particular population are scarce. Current study assesses incidence, timing and predictors of VTE in pancreatic cancer through different phases of disease.

METHODS

All pancreatic cancer patients treated in our tertiary referral center between 2013 through 2017 were studied. Occurrence of VTE was evaluated from diagnosis through end of follow-up or death. Relevant determinants of VTE were identified in logistic regression models. Hazard ratios were calculated to evaluate impact of VTE on overall survival.

RESULTS

In total, 361 patients were followed for a median period of 43 months; 64 were diagnosed with VTE (18%). Most were tumor related thrombosis (59%), incidental (75%) and occurred after anti-cancer treatment had been stopped (80%), only 1.6% occurred during remission phase. Stage IV pancreatic cancer was a predictor for VTE (hazard ratio (HR) 2.46, 95% confidence interval (CI) 0.9-6.8). Biliary drainage (HR 0.52, 95%CI 0.28-0.98) and tumor resection (HR 0.45, 95%CI 0.45-1.83) were protective factors. VTE was not associated with worse survival (HR 1.3; 95% CI 0.97-1.74).

CONCLUSIONS

VTE in pancreatic cancer is disease-stage dependent, with 80% occurring in advanced phases of disease when patients no longer receive active treatment. We speculate that this is the main reason for the absence of a survival effect of VTE in our cohort. These practice-based findings should be taken into account when considering wide-spread introduction of primary thromboprophylaxis in patients with pancreatic cancer.

Stabilin-2 deficiency increases thrombotic burden and alters the composition of venous thrombi in a mouse model

BACKGROUND

Stabilin-2 is an endocytic scavenger receptor that mediates the clearance of glycosaminoglycans, phosphatidylserine-expressing cells, and the von Willebrand factor-factor VIII (FVIII) complex. In a genome-wide screening study, pathogenic loss-of-function variants in the human STAB2 gene associated with an increased incidence of unprovoked venous thromboembolism (VTE). However, the specific mechanism(s) by which stabilin-2 deficiency influences the pathogenesis of VTE is unknown.

OBJECTIVES

The aim of this study was to assess the influence of stabilin-2 on deep vein thrombosis (DVT) and to characterize the underlying prothrombotic phenotype of stabilin-2 deficiency in a mouse model.

METHODS

DVT was induced using the inferior vena cava (IVC) stenosis model in two independent cohorts (littermates and non-littermates) of wild-type (Stab2+/+ ) and stabilin-2 (Stab2-/- )-deficient mice. Thrombus structure and contents were quantified by immunohistochemistry. Plasma procoagulant activity was assessed and complete blood counts were performed.

RESULTS

Incidence of thrombus formation was not altered between Stab2+/+ and Stab2-/- mice. When thrombi were formed, Stab2-/- mice developed significantly larger thrombi than Stab2+/+ controls. Thrombi from Stab2-/- mice contained significantly more leukocytes and citrullinated histone H3 than Stab2+/+ thrombi. Stab2-/- mice had increased FVIII activity. Circulating levels of monocytes and granulocytes were significantly elevated in Stab2-/- mice, and Stab2-/- mice had elevated plasma cell-free DNA 24 hours post-IVC stenosis compared to their Stab2+/+ counterparts.

CONCLUSIONS

These data suggest that stabilin-2 deficiency associates with a prothrombotic phenotype involving elevated levels of neutrophil extracellular trap-releasing leukocytes coupled with endogenous procoagulant activity, resulting in larger and qualitatively distinct venous thrombi.

Risk of venous thromboembolism associated with Janus kinase inhibitors for rheumatoid arthritis: case presentation and literature review

Janus kinase (JAK) inhibitors have been developed as disease-modifying antirheumatic drugs. Despite the positive therapeutic impacts of JAK inhibitors, concerns have been raised regarding the risk of venous thromboembolism (VTE), such as deep vein thrombosis (DVT) and pulmonary embolism (PE). A recent post hoc safety analysis of placebo-controlled trials of JAK inhibitors in rheumatoid arthritis (RA) reported an imbalance in the incidence of VTE for a 4-mg daily dose of baricitinib versus placebo. In a recent postmarketing surveillance trial for RA, a significantly higher incidence of PE was reported in treatment with tofacitinib (10 mg twice daily) compared with tofacitinib 5 mg or tumor necrosis factor inhibitors. We also experienced a case of massive PE occurring 3 months after starting baricitinib (4 mg once daily) for multiple biologic-resistant RA. Nevertheless, the evidence to support the role of JAK inhibitors in VTE risk remains insufficient. There are a number of predisposing conditions and risk factors for VTE. In addition to the known risk factors that can provoke VTE, advanced age, obesity, diabetes mellitus, hypertension, hyperlipidemia, and smoking can also contribute to its development. Greater VTE risk is noted in patients with chronic inflammatory conditions, particularly RA patients with uncontrolled disease activity and any comorbidity. Prior to the initiation of JAK inhibitors, clinicians should consider both the number and strength of VTE risk factors for each patient. In addition, clinicians should advise patients to seek prompt medical help if they develop clinical signs and symptoms that suggest VTE/PE.

Key Points • Patients with rheumatoid arthritis (RA) are at increased risk of venous thromboembolism (VTE), especially those with uncontrolled, high disease activity and those with comorbidities. • In addition to the well-known risk factors that provoke VTE events, advanced age and cardiovascular risk factors, such as obesity, diabetes mellitus, hypertension, hyperlipidemia, and smoking, should be considered risk factors for VTE. • Although a signal of VTE/pulmonary embolism (PE) risk with JAK inhibitors has been noted in RA patients who are already at high risk, the evidence is currently insufficient to support the increased risk of VTE during RA treatment with JAK inhibitors. • If there are no suitable alternatives, clinicians should prescribe JAK inhibitors with caution, considering both the strength of individual risk factors and the cumulative weight of all risk factors for each patient.

Evaluating post-operative venous thromboembolism risk in urology patients using a validated risk assessment model

Background

Venous thromboembolism (VTE) is an important cause of post-surgical morbidity and mortality. This study aimed to apply a validated risk assessment model to evaluate the risk of post-operative VTE in urology patients.

Methods

This prospective descriptive observational study used the Caprini risk assessment model to evaluate VTE risk in patients planned for elective urology surgery at a tertiary Johannesburg hospital from January to June 2020.

Results

Two hundred and twenty-six patients with a mean age of 52 years were evaluated for post-operative VTE risk. The population was generally overweight, with a mean BMI of 26.3 kg/m2. The mean Caprini score was 4.42, reflecting a population at high risk for post-operative VTE. There was no statistically significant difference between males and females in this regard. On average, participants had three risk factors for post-operative VTE. Fifteen per cent of all patients were at low risk for VTE, while 40.3% of participants were categorised as moderate risk. The category with the highest percentage of participants (44.7%) was the high-risk category (Caprini score ≥ 5). High-risk patients undergoing oncology surgery comprised 16.8% of the population, and these patients may require extended duration pharmacological thromboprophylaxis to prevent VTE. The most clinically significant risk factors for post-operative VTE included age, obesity, malignancy and HIV infection.

Conclusion

Venous thromboembolism may be difficult to diagnose, and clinicians may underestimate the risk for it to develop. Risk assessment models, such as the Caprini score, are objective and a practical tool to guide the application of thromboprophylaxis. The application of the Caprini RAM in the elective urological surgery population at Chris Hani Baragwanath Academic Hospital yields similar results to studies performed elsewhere on similar surgical populations. Further research is required to evaluate whether the actual incidence of VTE correlates with the risk assessment in this population. Clinician compliance with the use of RAMs as well as the corresponding recommendations for prophylaxis may need to be evaluated. A validated risk assessment model which accounts for procedure-specific risks in urology may be useful.

Direct oral anticoagulants (DOAC) for prevention of recurrent arterial or venous thromboembolic events (ATE/VTE) in myeloproliferative neoplasms

In patients with BCR-ABL-negative myeloproliferative neoplasms (MPN), arterial or venous thromboembolic events (ATE/VTE) are a major burden. In order to control these complications, vitamin K antagonists (VKA) are widely used. There is no robust evidence supporting the use of direct oral anticoagulants (DOAC) in MPN patients. We therefore compared the efficacy and safety of both anticoagulants in 71 cases from a cohort of 782 MPN patients. Seventy-one of 782 MPN patients (9.1%) had ATE/VTE with nine ATE (12.7%) and 62 VTE (87.3%). Forty-five of 71 ATE/VTE (63.4%) were treated with VKA and 26 (36.6%) with DOAC. The duration of anticoagulation therapy (p = 0.984), the number of patients receiving additional aspirin (p = 1.0), and the proportion of patients receiving cytoreductive therapy (p = 0.807) did not differ significantly between the VKA and DOAC groups. During anticoagulation therapy, significantly more relapses occurred under VKA (n = 16) compared to DOAC treatment (n = 0, p = 0.0003). However, during the entire observation period of median 3.2 years (0.1-20.4), ATE/VTE relapse-free survival (p = 0.2) did not differ significantly between the two anticoagulants. For all bleeding events (p = 0.516) or major bleeding (p = 1.0), no significant differences were observed between VKA and DOAC. In our experience, the use of DOAC was as effective and safe as VKA, possibly even potentially beneficial with a lower number of recurrences and no increased risk for bleedings. However, further and larger studies are required before DOAC can be routinely used in MPN patients.

Metabolic Syndrome Increases Risk of Venous Thromboembolism Recurrence after Acute Pulmonary Embolism

Rationale: Metabolic syndrome (MetS), the clinical clustering of hypertension, dyslipidemia, insulin resistance, and abdominal obesity, has been associated with a prothrombotic and hypofibrinolytic state, although data linking MetS with venous thromboembolism (VTE) remain limited.Objectives: The aim of this study was to measure the prevalence of MetS in patients with pulmonary embolism (PE) across a large population and to examine its impact on VTE recurrence.Methods: This was a retrospective, population-based analysis using deidentified information from a large statewide database, the Indiana Network for Patient Care. All patients with an International Classification of Diseases-defined diagnosis of PE from 2004 to 2017 were included. We measured the frequency with which patients with PE carried a comorbid diagnosis of each MetS component. Multiple logistic regression analysis was performed with VTE recurrence as the dependent variable to test the independent effect of MetS diagnosis, with a statistical model using a directed acyclic graph to account for potential confounders and mediators. Kaplan-Meier curves were constructed to compare rates of VTE recurrence over time based on the presence or absence of MetS and its individual components.Results: A total of 72,936 patients were included in this analysis. The most common MetS component was hypertension with a prevalence of 59%, followed by hyperlipidemia (41%), diabetes mellitus (24%), and obesity (22%). Of these patients, 69% had at least one comorbid component of MetS. The overall incidence of VTE recurrence was 17%, increasing stepwise with each additional MetS component and ranging from 6% in patients with zero components to 37% in those with all four. Logistic regression analysis yielded an adjusted odds ratio of 3.03 (95% CI, 2.90-3.16) for the effect of composite diagnosis requiring at least three of the four components of MetS diagnosis on VTE recurrence.Conclusions: The presence of comorbid MetS in patients with PE is associated with significantly higher rates of VTE recurrence, supporting the importance of recognizing these risk factors and initiating appropriate therapies to reduce recurrence risk.

Severe alpha-1-antitrypsin deficiency increases the risk of venous thromboembolism

BACKGROUND

Severe alpha-1-antitrypsin deficiency (AATD), phenotype PiZZ, is associated with increased risk of liver disease and chronic obstructive pulmonary disease (COPD), but the risk of venous thromboembolism (VTE) is unknown. Our aim was to evaluate the risk of VTE in individuals with severe AATD compared with control subjects from the general population.

METHODS

Individuals with severe AATD (n = 1577) were recruited from the Swedish national AATD register. Control subjects (n = 5969) were selected from the OLIN (Obstructive Lung Disease in Northern Sweden) studies, that include a random general population sample. Longitudinal data on VTE and diagnoses were obtained from the Swedish National Patient Registry. Associations were analyzed using multivariable Cox regression.

RESULTS

At inclusion, 46% of the AATD individuals and 53% of the controls were never-smokers. COPD was present in 46% of the AATD individuals compared with 4% of the controls. During a median follow-up of 18 years, 116 (7%) of the AATD individuals and 89 (1%) of the control subjects developed VTE, unadjusted hazard ratio 6.5 (95% confidence interval 4.9-8.6). Risk factors for incident VTE were male gender, age, COPD, cancer, and liver disease. Adjusting for these factors, the AATD individuals had a significantly higher risk of incident VTE, adjusted hazard ratio 4.2 (95% confidence interval 2.9-6.2) as compared with the controls.

CONCLUSION

Subjects with severe AATD have considerably increased risk of developing VTE compared with the general population, even after accounting for risk factors. This calls for optimized risk factor management and clinical follow-up of this patient group.

Circulating Plasma miRNA and Clinical/Hemodynamic Characteristics Provide Additional Predictive Information About Acute Pulmonary Thromboembolism, Chronic Thromboembolic Pulmonary Hypertension and Idiopathic Pulmonary Hypertension

Idiopathic pulmonary artery hypertension (IPAH), chronic thromboembolic pulmonary hypertension (CTEPH), and acute pulmonary embolism (APTE) are life-threatening cardiopulmonary diseases without specific surgical or medical treatment. Although APTE, CTEPH and IPAH are different pulmonary vascular diseases in terms of clinical presentation, prevalence, pathophysiology and prognosis, the identification of their circulating microRNA (miRNAs) might help in recognizing differences in their outcome evolution and clinical forms. The aim of this study was to describe the APTE, CTEPH, and IPAH-associated miRNAs and to predict their target genes. The target genes of the key differentially expressed miRNAs were analyzed, and functional enrichment analyses were carried out. The miRNAs were detected using RT-PCR. Finally, we incorporated plasma circulating miRNAs in baseline and clinical characteristics of the patients to detect differences between APTE and CTEPH in time of evolution, and differences between CTEPH and IPAH in diseases form. We found five top circulating plasma miRNAs in common with APTE, CTEPH and IPAH assembled in one conglomerate. Among them, miR-let-7i-5p expression was upregulated in APTE and IPAH, while miRNA-320a was upregulated in CTEP and IPAH. The network construction for target genes showed 11 genes regulated by let-7i-5p and 20 genes regulated by miR-320a, all of them regulators of pulmonary arterial adventitial fibroblasts, pulmonary artery endothelial cell, and pulmonary artery smooth muscle cells. AR (androgen receptor), a target gene of hsa-let-7i-5p and has-miR-320a, was enriched in pathways in cancer, whereas PRKCA (Protein Kinase C Alpha), also a target gene of hsa-let-7i-5p and has-miR-320a, was enriched in KEGG pathways, such as pathways in cancer, glioma, and PI3K-Akt signaling pathway. We inferred that CTEPH might be the consequence of abnormal remodeling in APTE, while unbalance between the hyperproliferative and apoptosis-resistant phenotype of pulmonary arterial adventitial fibroblasts, pulmonary artery endothelial cell and pulmonary artery smooth muscle cells in pulmonary artery confer differences in IPAH and CTEPH diseases form. We concluded that the incorporation of plasma circulating let-7i-5p and miRNA-320a in baseline and clinical characteristics of the patients reinforces differences between APTE and CTEPH in outcome evolution, as well as differences between CTEPH and IPAH in diseases form.

STOP leg clots-Swedish multicentre trial of outpatient prevention of leg clots: study protocol for a randomised controlled trial on the efficacy of intermittent pneumatic compression on venous thromboembolism in lower leg immobilised patients

INTRODUCTION

Leg immobilisation in a cast or an orthosis after lower limb injuries is associated with a high risk of complications of venous thromboembolism (VTE) and hampered healing. Current pharmacoprophylaxes of VTE are inefficient and associated with adverse events. Intermittent pneumatic compression (IPC) could represent a novel, efficient and safe VTE-prophylactic alternative that may enhance injury healing. The aim of STOP leg clots is to assess the efficacy of adjuvant IPC-therapy on reduction of VTE incidence and improvement of healing in lower leg immobilised outpatients.

METHODS AND ANALYSIS

STOP leg clots is a multicentre randomised controlled superiority trial. Eligible patients (700 patients/arm) with either an acute ankle fracture or Achilles tendon rupture will be randomised to either addition of IPC during lower-leg immobilisation or to treatment-as-usual. The primary outcome will be the total VTE incidence, that is, symptomatic and asymptomatic deep venous thrombosis (DVT) or symptomatic pulmonary embolism (PE), during the leg immobilisation period, approximately 6-8 weeks. DVT incidence will be assessed by screening whole leg compression duplex ultrasound at removal of leg immobilisation and/or clinically diagnosed within the time of immobilisation. Symptomatic PE will be verified by CT.Secondary outcomes will include patient-reported outcome using validated questionnaires, healing evaluated by measurements of tendon callus production and changes in VTE-prophylactic mechanisms assessed by blood flow and fibrinolysis. Data analyses will be blinded and based on the intention-to-treat.

ETHICS AND DISSEMINATION

Ethical approval was obtained by the ethical review board in Stockholm, Sweden, Dnr 2016/1573-31. The study will be conducted in accordance with the Helsinki declaration. The results of the study will be disseminated in peer-reviewed international journals.

TRIAL REGISTRATION

NCT03259204.

TIME SCHEDULE

1 September 2018 to 31 December 2022.

Metabolic syndrome increases risk of venous thromboembolism recurrence after acute deep vein thrombosis

An improved understanding of which patients are at higher risk of recurrent venous thromboembolism (VTE) is important to designing interventions to reduce degraded quality of life after VTE. Although metabolic syndrome (MetS), the clustering of hypertension, hyperlipidemia, diabetes mellitus, and obesity has been associated with a hypofibrinolytic state, data linking VTE recurrence with MetS remain limited. The purpose of this study was to measure the prevalence of MetS in patients with deep vein thrombosis (DVT) across a large population and determine its effect on VTE recurrence. This was a retrospective analysis of a large statewide database from 2004 to 2017. We measured the frequency with which patients with DVT carried a comorbid International Coding of Diseases diagnosis of MetS components. Association of MetS with VTE recurrence was tested with a multiple logistic regression model and VTE recurrence as the dependent variable. Risk of VTE recurrence conferred by each MetS component was assessed by Kaplan-Meier curves with the log-rank statistic. A total of 151 054 patients with DVT were included in this analysis. Recurrence of VTE occurred in 17% overall and increased stepwise with each criterion for MetS. All 4 components of MetS had significant adjusted odds ratios (OR) for VTE recurrence, with hyperlipidemia having the largest (OR, 1.8), representing the 4 largest ORs of all possible explanatory variables. All 4 MetS variables were significant on Kaplan-Meier analysis for recurrence of VTE. These data imply a role for appropriate therapies to reduce the effects of MetS as a way to reduce risk of VTE recurrence.

Natural Language Processing Performance for the Identification of Venous Thromboembolism in an Integrated Healthcare System

Real-time identification of venous thromboembolism (VTE), defined as deep vein thrombosis (DVT) and pulmonary embolism (PE), can inform a healthcare organization's understanding of these events and be used to improve care. In a former publication, we reported the performance of an electronic medical record (EMR) interrogation tool that employs natural language processing (NLP) of imaging studies for the diagnosis of venous thromboembolism. Because we transitioned from the legacy electronic medical record to the Cerner product, iCentra, we now report the operating characteristics of the NLP EMR interrogation tool in the new EMR environment. Two hundred randomly selected patient encounters for which the imaging report assessed by NLP that revealed VTE was present were reviewed. These included one hundred imaging studies for which PE was identified. These included computed tomography pulmonary angiography-CTPA, ventilation perfusion-V/Q scan, and CT angiography of the chest/ abdomen/pelvis. One hundred randomly selected comprehensive ultrasound (CUS) that identified DVT were also obtained. For comparison, one hundred patient encounters in which PE was suspected and imaging was negative for PE (CTPA or V/Q) and 100 cases of suspected DVT with negative CUS as reported by NLP were also selected. Manual chart review of the 400 charts was performed and we report the sensitivity, specificity, positive and negative predictive values of NLP compared with manual chart review. NLP and manual review agreed on the presence of PE in 99 of 100 cases, the presence of DVT in 96 of 100 cases, the absence of PE in 99 of 100 cases and the absence of DVT in all 100 cases. When compared with manual chart review, NLP interrogation of CUS, CTPA, CT angiography of the chest, and V/Q scan yielded a sensitivity = 93.3%, specificity = 99.6%, positive predictive value = 97.1%, and negative predictive value = 99%.

Risk Factors and Anticoagulation Therapy in Patients With Isolated Distal Deep Vein Thrombosis in the Early Post-operative Period After Thoracic Surgery

Background: Isolated distal deep vein thrombosis (IDDVT) accounts for ~50% of all patients diagnosed with deep venous thrombosis (DVT), but the diagnosis and optimal management of IDDVT remains unclear and controversial. The aim of this study was to explore potential risk factors and predictors of IDDVT, and to evaluate different strategies of anticoagulation therapy.

Methods: A total of 310 consecutive patients after thoracic surgery, who underwent whole-leg ultrasonography as well as routine measurements of D-dimer levels before and after surgery were evaluated. The general clinical data, anticoagulant therapy, pre- and postoperative D-dimer levels were collected. Differences between IDDVT, DVT and non-DVT groups were calculated. Logistic regression analysis was used to analyze risk factors of postoperative IDDVT.

Results: Age and postoperative D-dimer levels were significantly higher in IDDVT group than in non DVT group (p = 0.0053 and p < 0.001, respectively). Logistic regression analysis showed that postoperative D-dimer level was a significant independent predictor of IDDVT even when adjusted for age and operation method (p = 0.0003). There were no significant side effects associated with both full-dose and half-dose anticoagulation regimens. Half-dose therapy was associated with a significant decrease in the requirement for anticoagulation medications after discharge (p = 0.0002).

Conclusion: Age and D-dimer levels after surgery are strong predictors of IDDVT following thoracic surgery. Half-dose therapeutic anticoagulation has the same efficiency in preventing IDDVT progression, is not associated with any additional risks of adverse effects compared to a full-dose regimen, and may be adopted for treating IDDVT patients after thoracic surgery.

Anticoagulant treatment for venous thromboembolism: A pooled analysis and additional results of the XALIA and XALIA-LEA noninterventional studies

BACKGROUND

The XALIA and XALIA-LEA prospective, noninterventional studies investigated the safety and effectiveness of rivaroxaban versus standard anticoagulation for venous thromboembolism (VTE) treatment in routine clinical practice across global regions.

OBJECTIVES

This pooled analysis combined their data to determine the incidence of thromboembolic and bleeding events in both treatment groups and addressed specific bleeding patterns in a broad range of patients.

METHODS

Patients with objectively confirmed VTE and an indication for ≥3 months' anticoagulation treatment received rivaroxaban or standard anticoagulation (eg, initial treatment with heparin/fondaparinux, followed by a vitamin K antagonist [VKA]). Treatment choice, dose, management, and duration were at the physician's discretion. Primary outcomes (major bleeding, recurrent VTE, and all-cause mortality) were compared between the two treatment groups. Propensity score stratification, and matching were used to reduce bias due to confounding variables.

RESULTS

Overall, 7129 patients were enrolled from 36 countries; 6445 and 2714 patients were included in the propensity score-stratified and -matched analyses, respectively. Major bleeding and incidences of recurrent VTE were similar between treatment groups; all-cause mortality was lower with rivaroxaban than with standard anticoagulation. The incidences of genitourinary bleeding were higher with rivaroxaban than with standard anticoagulation therapy (46 and 23 events in the matched analysis, respectively). VKA management in real-world practice was suboptimal.

CONCLUSION

XALIA and XALIA-LEA show similar safety and effectiveness profiles of rivaroxaban and standard anticoagulation for VTE treatment in routine practice in many parts of the world. The observations are consistent with results from the phase III EINSTEIN randomized controlled trials.

Laterality of lower extremity deep vein thrombosis after colectomy: A retrospective study using the national inpatient sample

BACKGROUND AND AIMS

Deep venous thrombosis (DVT) is known to occur preferentially on the left lower extremity. The renowned surgeon Denis Burkitt advanced the theory that a heavy sigmoid colon would compress the left pelvic veins and predispose to DVT. Our study aimed to evaluate this hypothesis by comparing the laterality distributions with and without a prior colectomy.

METHODS

We conducted a retrospective analysis of the 2016 National Inpatient Sample database by stratifying the patients at any age with acute DVT of lower extremity by history of prior colectomy, thereby eliminating local gut mechanical factors in the development of DVT. We compared the laterality distribution (i.e., left, right, bilateral, and unspecified) between the patients with and without a prior colectomy. We also conducted a subgroup analysis by the sex category to examine the difference in laterality distribution for male and female patients. Chi-square test for independence was used. P value ≤0.05 was considered statistically significant.

RESULTS

We found an estimated total of 342,525 cases. Among patients without a prior colectomy, 136,605 (41.6%) were left-sided DVT versus 119,555 (36.4%) right-sided, with 55,555 bilateral and 16,865 unspecified. Among patients with a prior colectomy, 5,750 (41.2%) were left-sided, 5,000 (35.9%) were right-sided, 2,345 were bilateral and 850 were unspecified. The laterality distribution between the two groups was not significantly different (p = .167). The left-side predominance disappeared only in males with a prior colectomy (37.1% for left vs. 38.9% for right, p = .027).

CONCLUSIONS

Our findings did not confirm the Burkitt's hypothesis. The left-side predominance of lower extremity DVT was attenuated only in male patients with a prior colectomy.

Indigo Aspiration System for Treatment of Pulmonary Embolism: Results of the EXTRACT-PE Trial

OBJECTIVES

This study sought to prospectively evaluate the safety and efficacy of the Indigo aspiration system in submassive acute pulmonary embolism (PE).

BACKGROUND

PE treatment with thrombolytics has bleeding risks. Aspiration thrombectomy can remove thrombus without thrombolytics, but data are lacking.

METHODS

This study was a prospective, single-arm, multicenter study that enrolled patients with symptomatic acute PE ≤14 days, systolic blood pressure ≥90 mm Hg, and right ventricular-to-left ventricular (RV/LV) ratio >0.9. The primary efficacy endpoint was change in RV/LV ratio from baseline to 48 h post-procedure on core lab-adjudicated computed tomography angiography. The primary safety endpoint was a composite of 48-h major adverse events: device-related death, major bleeding, and device-related serious adverse events (clinical deterioration, pulmonary vascular, or cardiac injury). All sites received Institutional Review Board approval.

RESULTS

A total of 119 patients (mean age 59.8 ± 15.0 years) were enrolled at 22 U.S. sites between November 2017 and March 2019. Median device insertion to removal time was 37.0 (interquartile range: 23.5 to 60.0) min. Two (1.7%) patients received intraprocedural thrombolytics. Mean RV/LV ratio reduction from baseline to 48 h post-procedure was 0.43 (95% confidence interval: 0.38 to 0.47; p < 0.0001). Two (1.7%) patients experienced 3 major adverse events. Rates of cardiac injury, pulmonary vascular injury, clinical deterioration, major bleeding, and device-related death at 48 h were 0%, 1.7%, 1.7%, 1.7%, and 0.8%, respectively.

CONCLUSIONS

In this prospective, multicenter study the Indigo aspiration system was associated with a significant reduction in the RV/LV ratio and a low major adverse event rate in submassive PE patients. Intraprocedural thrombolytic drugs were avoided in 98.3% of patients. (Evaluating the Safety and Efficacy of the Indigo aspiration system in Acute Pulmonary Embolism [EXTRACT-PE]; NCT03218566).

Incidence of venous thromboembolism following initiation of non-steroidal anti-inflammatory drugs in U.S. women

OBJECTIVE

To evaluate the risk of venous thromboembolism (VTE, i.e. deep vein thrombosis or pulmonary embolism, or both) following new use of NSAIDs in a long-term cohort of U.S. women.

METHODS

We investigated initiation of coxibs and traditional NSAIDs (excluding aspirin) and incident VTE in 39 876 women enrolled in the Women's Health Study from 1993-95 and followed with yearly questionnaires until 2012. We defined initiation as the first reported use of NSAIDs for ≥4 days per month. Incident VTE was confirmed by an end point committee. We estimated hazard ratios (HRs) and risk differences (RDs, expressed as percentages) comparing NSAID initiation with non-initiation and acetaminophen initiation (active comparator) via standardization using a propensity score that incorporated age, BMI, calendar time, and relevant medical, behavioural, and socioeconomic variables updated over time.

RESULTS

The HR (95% CI) for risk of VTE in the as treated analyses comparing initiation with non-initiation, was 1.5 (1.2, 1.8) for any NSAID, 1.3 (1.1, 1.7) for traditional NSAIDs, and 2.0 (1.3, 3.1) for coxibs, with 2-year RDs 0.11, 0.08 and 0.32, respectively. When comparing the risk of VTE after initiation of any NSAID with that after acetaminophen initiation, the HRs were 0.9 (0.6, 1.5), 0.9 (0.5, 1.5) and 1.4 (0.6, 3.4), with 2-year RDs 0.03, -0.01, and 0.13, respectively.

CONCLUSION

New use of NSAIDs was associated with increased VTE risk compared with non-use, but the association was null or diminished when compared with acetaminophen initiation. Elevated VTE risks associated with NSAID use in observational studies may in part reflect different baseline risks among individuals who need analgesics and may overstate the risk patients incur compared with pharmacologic alternatives.

Statin Use is Associated with Reduced Risk of Recurrence in Patients with Venous Thromboembolism

BACKGROUND

Statin therapy appears to reduce incidence of venous thromboembolism in secondary analyses of non-venous thromboembolism trials, but no evidence has shown effect of statins in large population samples. The objective of this study was to examine the magnitude of the effect of statin therapy on venous thromboembolism recurrence across a large statewide population.

METHODS

This was a retrospective analysis of the Indiana Network for Patient Care database. All patients with an International Classification of Diseases-defined diagnosis of either deep vein thrombosis or pulmonary embolism from 2004-2017 were included. We collected Generic Product Identifier codes to determine whether patients had been prescribed a statin medication and divided patients into 2 groups: + or - statin. We then performed a propensity-matching analysis to balance covariates and created a final logistic regression model with statin use as the predictor variable and venous thromboembolism recurrence as the dependent variable.

RESULTS

This study included a total of 192,908 patients with documented statin use in 13.5%. Venous thromboembolism recurrence occurred in 16% of all patients over the study period. After propensity matching, patients not on a statin were found to have significantly higher rates of venous thromboembolism recurrence (20% vs 16%, P < .0001). Logistic regression yielded an odds ratio of 0.75 (95% confidence interval, 0.72-0.79) for venous thromboembolism recurrence for those on statin therapy.

CONCLUSIONS

We found that a statin prescription reduced risk of venous thromboembolism recurrence by approximately 25% after adjusting for risk factors, supporting the adjunctive role of statins in the prevention of venous thromboembolism recurrence.

The diagnostic value of D-dimer with simplified Geneva score (SGS) pre-test in the diagnosis of pulmonary embolism (PE)

Background

Pulmonary embolism (PE) is the third most common cardiovascular syndrome with an average annual incidence rate of 77 per 100,000 population in the worldwide. The diagnose algorithms for suspected PE are generally include clinical scoring assessment and plasma D-dimer evaluation, patients with high risk of PE require computed tomographic pulmonary angiogram (CTPA) detection for confirmation.

Methods

In this retrospective analysis, 1035 patients with suspected PE were recruited. All the patients were clinically received simplified Geneva score (SGS) pre-test, determination of plasma D-dimer level, and CTPA detection. All enrolled patients were grouped according to the CTPA results: PE patients and non-PE patients. Then, receiver operating characteristic (ROC) curve were constructed to determine the optimal D-dimer cutoff point value which is based on Yonden’s index (YI).

Results

294 (28.4%) patients were confirmed with PE and 741(71.6%) individuals were regarded as non-PE cases by CTPA detection. Using the SGS pre-test, 829 (80.1%) patients were classified PE-unlikely (SGS ≤ 2) and 206 (19.9%) patients were PE-likely (SGS ≥ 3). Patients with D-dimer levels above 1.96 mg/L had a significant risk to suffer from PE (area under curve (AUC), 0.707; 95% CI, 0.678–0.735; p < 0.05). Meanwhile, in patients with SGS ≥ 3, the D-dimer cutoff point value moved to 2.2 mg/L (AUC, 0.644; 95% CI, 0.574–0.709; p < 0.05).

Conclusion

D-dimer test in combination with SGS pre-test could improve the accuracy of PE diagnosis. Patients with D-dimer levels over 1.96 mg/L (4 times of the normal level) have a significant risk for PE. In patients with SGS ≥ 3, the D-dimer cutoff point concentration for PE risk moves to the levels of 2.2 mg/L.

Thrombotic Risk in Cancer Patients: Diagnosis and Management of Venous Thromboembolism

Venous thromboembolism (VTE) represents a major health problem, especially in cancer patients, who experience a significantly higher incidence of both deep vein thrombosis and pulmonary embolism compared to the general population. Indeed, patients with cancer have a prothrombotic state resulting in both increased expression of procoagulants and suppression of fibrinolytic activity. In addition, VTE increases the morbidity and mortality of these patients. For all these reasons, the prevention and treatment of VTE in cancer setting represent major challenges in daily practice. In general, low-molecular-weight heparin monotherapy is the standard of care for the management of cancer-associated VTE, as Vitamin K antagonists are less effective in this setting. Direct oral anticoagulants offer a potentially promising treatment option for cancer patients with VTE, since recent studies demonstrated their efficacy and safety also in this peculiar setting.

Identification of cryptotanshinone from Tongmai to inhibit thrombosis in zebrafish via regulating oxidative stress and coagulation cascade

BACKGROUND

Thromboembolic events are leading causes of mortality and morbidity all over the world. Tongmai (TM) is a botanical drug with valid clinical efficacy and safety in the management of thrombosis and ischemic cardiovascular diseases, however, its active compounds and underlying mechanism are largely unclear.

PURPOSE

To investigate the endogenous effects, therapeutic mechanism and active compounds of TM in thrombus formation.

STUDY DESIGN

Combined with transgenic zebrafish models and high-content imaging system, this study evaluated the endogenous antithrombotic effects of TM and screened for the active compounds.

METHODS

The PHZ-induced thrombotic model in erythrocytes or platelets labeled transgenic zebrafish were established, to dynamically evaluate the antithrombotic effects of TM. The oxidative damage levels were analyzed by specific fluorescent probes, and the expression levels of key factors in coagulation cascades and platelet activation were examined by QPCR. TM were dissected into fractions by reverse phase chromatography and subsequently screened for their antithrombotic effects in the transgenic fish models. The compounds of the active TM fraction were then analyzed by UPLC-Q-TOF analysis and further verified for their antithrombotic effects and mechanisms.

RESULTS

In PHZ-induced zebrafish thrombotic model, TM incubation markedly increased cardiac blood flow, decreased peripheral erythrocytes aggregation, and recovered peripheral platelet circulation. Besides, the levels of oxidative stress and lipid peroxidation were increased in the PHZ-induced thrombotic fish, which were greatly decreased by TM treatment. Moreover, TM significantly reduced the expression of coagulation factor II (thrombin) and the downstream fibrinogen. In order to identify the active compounds of TM, four fractions were separated from the extract by reverse phase chromatography, which were subsequently screened for their antithrombotic effects in the fish model. As a result, fraction 4 showed the strongest effect in inhibiting thrombosis. Finally, through UPLC-Q-TOF analysis and endogenous screening, cryptotanshione was identified as the main active compound with antithrombotic effects.

CONCLUSION

Our study demonstrated the endogenous antithrombotic effects of TM, which is possibly mediated by inhibiting oxidative stress and coagulation cascade. Cryptotanshione was identified as a major compound with antithrombotic activity and is a promising candidate for novel antithrombotic therapy.

Prevention of Pulmonary and Venous Thromboembolism Post Coronary Artery Bypass Graft Surgery - Literature Review

Objective

The current review evaluates recent literature on the different aspects of prophylaxis in postoperative pulmonary and venous thromboembolism and their main risk factors.

Methods

The literature survey was carried out based on the PubMed data using the keywords “coronary artery bypass graft” and “venous thromboembolism” as components of the search field title.

Results

Studies reported several risk factors for postoperative thromboembolism including advanced age, postoperative immobilization, type of thromboprophylaxis, obesity, and location of the surgery.

Conclusion

According to the studies, tailored prophylaxis could be easily adapted to decrease the intensity and duration of postoperative thromboembolism in a patient with several disorders and comorbidities, especially in cardiovascular disease.

Complications of Thoracolumbar Adult Spinal Deformity Surgery

Adult spinal deformity (ASD) is a challenging problem for spine surgeons given the high risk of complications, both medical and surgical. Surgeons should have a high index of suspicion for medical complications, including cardiac, pulmonary, thromboembolic, genitourinary and gastrointestinal, renal, cognitive and psychiatric, and skin conditions, in the perioperative period and have a low threshold for involving specialists. Surgical complications, including neurologic injuries, vascular injuries, proximal junctional kyphosis, durotomy, and pseudarthrosis and rod fracture, can be devastating for the patient and costly to the health-care system. Mortality rates have been reported to be between 1.0% and 3.5% following ASD surgery. With the increasing rate of ASD surgery, surgeons should properly counsel patients about these risks and have a high index of suspicion for complications in the perioperative period.

A Comprehensive Literature Review on the Management of Distal Deep Vein Thrombosis

Deep vein thrombosis (DVT) is a relatively common clinical entity with significant morbidity and mortality. Acute pulmonary embolism (PE) is the most significant complication of DVT and warrants immediate attention. The location of the DVT has a substantial impact on its ability to break off and travel to the pulmonary vasculature, causing a PE. Proximal DVT is more likely to cause a PE than a distal DVT. The widely accepted management for proximal DVT is anticoagulation. However, the management of distal DVT is unclear. This review article discusses factors that increase the risk of PE in patients with distal DVT, guidance on how to categorize patients into high and low-risk categories, and the recommended management for each category.

Bayesian network analysis of plasma microRNA sequencing data in patients with venous thrombosis

MicroRNAs (miRNAs) are small regulatory RNAs participating to several biological processes and known to be involved in various pathologies. Measurable in body fluids, miRNAs have been proposed to serve as efficient biomarkers for diseases and/or associated traits. Here, we performed a next-generation-sequencing based profiling of plasma miRNAs in 344 patients with venous thrombosis (VT) and assessed the association of plasma miRNA levels with several haemostatic traits and the risk of VT recurrence. Among the most significant findings, we detected an association between hsa-miR-199b-3p and haematocrit levels (P = 0.0016), these two markers having both been independently reported to associate with VT risk. We also observed suggestive evidence for association of hsa-miR-370-3p (P = 0.019), hsa-miR-27b-3p (P = 0.016) and hsa-miR-222-3p (P = 0.049) with VT recurrence, the observations at the latter two miRNAs confirming the recent findings of Wang et al. Besides, by conducting Genome-Wide Association Studies on miRNA levels and meta-analyzing our results with some publicly available, we identified 21 new associations of single nucleotide polymorphisms with plasma miRNA levels at the statistical significance threshold of P < 5 × 10-8, some of these associations pertaining to thrombosis associated mechanisms. In conclusion, this study provides novel data about the impact of miRNAs' variability in haemostasis and new arguments supporting the association of few miRNAs with the risk of recurrence in patients with venous thrombosis.

Percutaneous Vacuum-Assisted Thrombectomy Using AngioVac Aspiration System

BACKGROUND

Surgical embolectomy and thrombolytic therapy are two common approaches for the treatment of large intra-cardiac or intravascular thrombi to prevent new or worsening pulmonary embolism (PE). Considering high operative mortality with surgical embolectomy and high bleeding risk with thrombolytic therapy, patients who are poor candidates for these treatments may benefit from percutaneous aspiration thrombectomy/Vacuum-assisted thrombectomy (VAT). AngioVac aspiration system was granted 510(k) clearance by the United States Food and Drug Administration (FDA) in April 2009. We present a case series to describe its use and outcomes in evacuating large caval thrombi or intracardiac masses.

METHODS

We did a retrospective analysis of AngioVac catheter based thrombectomy in 16 consecutive patients treated between January 2016 and January 2019 to report case characteristics and in-hospital clinical outcomes.

RESULTS

Sixteen patients (mean age 48) underwent 16 AngioVac procedures over 48 months. Indications included intracardiac mass (68.8%), caval thrombus (56.3%), and catheter associated thrombus (43.8%). 7 (43.8%) patients had concurrent PE. Peri-procedure mortality was 0% and in-hospital mortality was 12.5% at a mean follow-up of 14 days. There were no pulmonary hemorrhages, strokes or myocardial infarctions. 62.5% had a significant drop in hemoglobin, which required a blood transfusion but there was no episode of overt bleeding.

CONCLUSION

The AngioVac aspiration system has been shown to be effective at aspirating large volumes of intravascular and intracardiac thrombus. It is a reasonable alternative to surgical thrombectomy in patients with large central thrombi or masses in-transit who are at risk of complicated PE.

Effect of metabolic syndrome on mean pulmonary arterial pressures in patients with acute pulmonary embolism treated with catheter-directed thrombolysis

BACKGROUND

Metabolic syndrome (MetS) has been associated with a procoagulant and hypofibrinolytic state. Current data exploring the role of MetS in venous thromboembolism (VTE) are limited. The objective was to measure the prevalence of MetS in patients with acute PE receiving catheter-directed thrombolysis (CDT) and to investigate its effect on mean pulmonary arterial pressure and overall treatment success.

METHODS

We used a 3-year prospective registry of ED patients with acute PE with severity qualifying for activation of a PE response team (PERT). All patients had CDT with catheter-measured mPAP and angiography. The presence or absence of MetS components were extracted from chart review based on the following criteria: 1. body mass index (BMI) >30 kg/m²; 2. diagnosed hypertension; 3. diabetes mellitus (including HbA1c >6.5%) and; 4. dyslipidemia (including triglycerides >150 mg/dL or high-density lipoprotein <40 mg/dL).

RESULTS

Of the 134 patients, 85% met the criteria for at least one of four MetS components, with obesity being most common, present in 71%. Results demonstrated a positive concordance between the number of criteria for MetS and MPAP, both pre- and post-fibrinolysis, as pressures tended to increase with each additional MetS criterion. Multivariate regression analysis determined age (-), BMI (+) and hypertension (+) to be significant independent predictor variables for mPAP.

CONCLUSIONS

MetS was common in patients with more severe manifestations of PE and was associated with higher mPAP values both at diagnosis and following treatment with CDT.