[Angiology and hemostasis: what's new in 2023]

We discuss four topics among the angiology and hemostasis studies of importance in 2023. The BASIL-2 study provides new data for the management of chronic limb-threatening ischemia by comparing surgical and endovascular treatment. The new classification of antiphospholipid antibody (aPL) syndrome integrates new clinical elements and gives a different weight among the isotype and titer of aPL. Concizumab, an antibody targeting the tissue factor pathway inhibitor, broadens the therapeutic arsenal for hemophilia A and B as evidenced by the results of the EXPLORER 7 study. The PREVENT-CLOT and CASTING study focus on the prevention of thrombosis after trauma, by testing the role of aspirin or the lack of thromboprophylaxis, respectively.

Obesity as a Predictor for Pulmonary Embolism and Performance of the Age-Adjusted D-Dimer Strategy in Obese Patients with Suspected Pulmonary Embolism

INTRODUCTION

 Obesity is a risk factor for venous thromboembolism, but studies evaluating its association with pulmonary embolism (PE) in patients with suspected PE are lacking.

OBJECTIVES

 To evaluate whether body mass index (BMI) and obesity (i.e., BMI ≥30 kg/m2) are associated with confirmed PE in patients with suspected PE and to assess the efficiency and safety of the age-adjusted D-dimer strategy in obese patients.

METHODS

 We conducted a secondary analysis of a multinational, prospective study, in which patients with suspected PE were managed according to the age-adjusted D-dimer strategy and followed for 3 months. Outcomes were objectively confirmed PE at initial presentation, and efficiency and failure rate of the diagnostic strategy. Associations between BMI and obesity, and PE were examined using a log-binomial model that was adjusted for clinical probability and hypoxia.

RESULTS

 We included 1,593 patients (median age: 59 years; 56% women; 22% obese). BMI and obesity were not associated with confirmed PE. The use of the age-adjusted instead of the conventional D-dimer cut-off increased the proportion of obese patients in whom PE was considered ruled out without imaging from 28 to 38%. The 3-month failure rate in obese patients who were left untreated based on a negative age-adjusted D-dimer cut-off test was 0.0% (95% confidence interval: 0.0-2.9%).

CONCLUSION

 BMI on a continuous linear scale and obesity were not predictors of confirmed PE among patients presenting with a clinical suspicion of PE. The age-adjusted D-dimer strategy appeared safe in ruling out PE in obese patients with suspected PE.

Pulmonary embolism risk stratification: external validation of the 4-level Clinical Pretest Probability Score (4PEPS)

Background

The 4-level clinical pretest probability score (4PEPS) was recently introduced as a clinical decision rule for the diagnosis of pulmonary embolism (PE). Based on the score, patients are classified into clinical pretest probability categories (c-PTP). The "very low" category aims at excluding PE without further testing; "low" and "moderate" categories require D-dimer testing with specific thresholds, while patients with a "high" pretest directly proceed to imaging.

Objectives

To provide further external validation of the 4PEPS model.

Methods

The 4PEPS was applied to a previously collected prospective database of 756 patients with clinically suspected PE enrolled from European emergency departments in 2002 to 2003. The safety threshold for the failure rate in our study was calculated at 1.95% based on a 26% prevalence of PE in our study, as per the International Society on Thrombosis and Haemostasis Scientific and Standardization Committee guidance.

Results

Patients were classified as follows: 90 (12%) in the very low c-PTP group, of whom 5 (5.6%; 95% CI, 2.4%-12.4%) had PE; 363 (49%) in the low c-PTP group, of whom 34 had PE (9.4%); 246 (34%) in the moderate c-PTP group, of whom 124 (50%) had PE; and 35 (5%) in the high c-PTP group of whom 30 (86%) had PE. Overall, the failure rate of the 4PEPS was 9/734 (1.2%; 95% CI, 0.59%-2.23%) Overall, 9 out of 734 patients (1.2%; 95% CI, 0.59%-2.23%) were diagnosed with PE despite a negative 4PEPS rule; 5 (5.6%) from the very low c-PTP group, 3 (1.4%) in the low c-PTP group, and 1 (3.2%) in the moderate c-PTP group.

Conclusion

We provide external validation data of the 4PEPS. In this high-prevalence cohort (26% prevalence), PE prevalence in the very low-risk group was higher than expected. A prospective validation study is needed before implementing the 4PEPS model in routine clinical practice.

[Anticoagulant treatment in pulmonary embolism : how to initiate and how to pursue ?]

Pulmonary embolism (PE) is associated with significant morbidity and mortality in the absence of properly prescribed anticoagulant treatment. Direct oral anticoagulants (DOACs) are currently the anticoagulant treatment of first choice. The quality of anticoagulation in the acute phase of PE is a major determinant of patients' prognosis. The dose regimens for the initiation phase must therefore be rigorously respected to ensure the efficacy of the treatment. For the maintenance phase, the reduced doses used in atrial fibrillation are not applicable in venous thromboembolism (VTE) except for edoxaban. Finally, for long-term secondary prevention in patients at risk of VTE recurrence, reduced dose DOACs are currently a very interesting option in terms of benefit-risk balance for the majority of patients.

Use of patient-reported outcome measures in patients with venous thromboembolism: communication from the ISTH SSC Subcommittee on Predictive and Diagnostic Variables in Thrombotic Disease

Patient-reported outcome measures (PROMs) are patient-completed instruments that capture patient-perceived health status and well-being. PROMs measure disease impact and outcomes of care as reported by those who experience the disease. After pulmonary embolism or deep vein thrombosis, patients may face a broad spectrum of complications and long-term sequelae beyond the usual quality-of-care indicators of recurrent venous thromboembolism (VTE), bleeding complications, and survival. The full impact of VTE on individual patients can only be captured by assessing all relevant health outcomes from the patient's perspective in addition to the traditionally recognized complications. Defining and measuring all important outcomes will help facilitate treatment tailored to the needs and preferences of patients and may improve health outcomes. The International Society on Thrombosis and Haemostasis Scientific and Standardization Committee Subcommittee on Predictive and Diagnostic Variables in Thrombotic Disease endorsed the International Consortium for Health Outcomes Measurement (ICHOM) VTE project on development of a standardized set of patient-centered outcome measures for patients with VTE. In this communication, the course and result of the project are summarized, and based on these findings, we propose recommendations for the use of PROMs during clinical follow-up of patients with VTE. We describe challenges to implementation of PROMs and explore barriers and enablers.

Enoxaparin for symptomatic COVID-19 managed in the ambulatory setting: An individual patient level analysis of the OVID and ETHIC trials

BACKGROUND

Antithrombotic treatment may improve the disease course in non-critically ill, symptomatic COVID-19 outpatients.

METHODS

We performed an individual patient-level analysis of the OVID and ETHIC randomized controlled trials, which compared enoxaparin thromboprophylaxis for either 14 (OVID) or 21 days (ETHIC) vs. no thromboprophylaxis for outpatients with symptomatic COVID-19 and at least one additional risk factor. The primary efficacy outcome included all-cause hospitalization and all-cause death within 30 days from randomization. Both studies were prematurely stopped for futility. Secondary efficacy outcomes were major symptomatic venous thromboembolic events, arterial cardiovascular events, or their composite occurring within 30 days from randomization. The same outcomes were assessed over a 90-day follow-up. The primary safety outcome was major bleeding (ISTH criteria).

RESULTS

A total of 691 patients were randomized: 339 to receive enoxaparin and 352 to the control group. Over 30-day follow-up, the primary efficacy outcome occurred in 6.0 % of patients in the enoxaparin group vs. 5.8 % of controls for a risk ratio (RR) of 1.05 (95%CI 0.57-1.92). The incidence of major symptomatic venous thromboembolic events and arterial cardiovascular events was 0.9 % vs. 1.8 %, respectively (RR 0.52; 95%CI 0.13-2.06). Most cardiovascular thromboembolic events were represented by symptomatic venous thromboembolic events, occurring in 0.6 % vs. 1.5 % of patients, respectively. A similar distribution of outcomes between the treatment groups was observed over 90 days. No major bleeding occurred in the enoxaparin group vs. one (0.3 %) in the control group.

CONCLUSIONS

We found no evidence for the clinical benefit of early administration of enoxaparin thromboprophylaxis in outpatients with symptomatic COVID-19. These results should be interpreted taking into consideration the relatively low occurrence of events.

Diagnostic management of acute pulmonary embolism: a prediction model based on a patient data meta-analysis

AIMS

Risk stratification is used for decisions regarding need for imaging in patients with clinically suspected acute pulmonary embolism (PE). The aim was to develop a clinical prediction model that provides an individualized, accurate probability estimate for the presence of acute PE in patients with suspected disease based on readily available clinical items and D-dimer concentrations.

METHODS AND RESULTS

An individual patient data meta-analysis was performed based on sixteen cross-sectional or prospective studies with data from 28 305 adult patients with clinically suspected PE from various clinical settings, including primary care, emergency care, hospitalized and nursing home patients. A multilevel logistic regression model was built and validated including ten a priori defined objective candidate predictors to predict objectively confirmed PE at baseline or venous thromboembolism (VTE) during follow-up of 30 to 90 days. Multiple imputation was used for missing data. Backward elimination was performed with a P-value <0.10. Discrimination (c-statistic with 95% confidence intervals [CI] and prediction intervals [PI]) and calibration (outcome:expected [O:E] ratio and calibration plot) were evaluated based on internal-external cross-validation. The accuracy of the model was subsequently compared with algorithms based on the Wells score and D-dimer testing. The final model included age (in years), sex, previous VTE, recent surgery or immobilization, haemoptysis, cancer, clinical signs of deep vein thrombosis, inpatient status, D-dimer (in µg/L), and an interaction term between age and D-dimer. The pooled c-statistic was 0.87 (95% CI, 0.85-0.89; 95% PI, 0.77-0.93) and overall calibration was very good (pooled O:E ratio, 0.99; 95% CI, 0.87-1.14; 95% PI, 0.55-1.79). The model slightly overestimated VTE probability in the lower range of estimated probabilities. Discrimination of the current model in the validation data sets was better than that of the Wells score combined with a D-dimer threshold based on age (c-statistic 0.73; 95% CI, 0.70-0.75) or structured clinical pretest probability (c-statistic 0.79; 95% CI, 0.76-0.81).

CONCLUSION

The present model provides an absolute, individualized probability of PE presence in a broad population of patients with suspected PE, with very good discrimination and calibration. Its clinical utility needs to be evaluated in a prospective management or impact study.

REGISTRATION

PROSPERO ID 89366.

External validation of the PEGeD diagnostic algorithm for suspected pulmonary embolism in an independent cohort

Sequential diagnostic algorithms are used in the case of suspected pulmonary embolism (PE). The PEGeD study proposed a new diagnostic strategy to reduce the use of computed tomography pulmonary angiography (CTPA). We aimed to externally validate this diagnostic strategy in an independent cohort. We analyzed data from 3 prospective studies of outpatients with suspected PE. As per the PEGeD algorithm, patients were classified as having a low, moderate, or high clinical pretest probability (C-PTP). PE was excluded with a D-dimer <1000 ng/mL in case of low C-PTP and <500 ng/mL in case of moderate C-PTP. We assessed the yield and safety of this approach and compared them with those of previously validated algorithms. Among the 3308 evaluated patients, 1615 (49%) patients could have had PE excluded according to the PEGeD algorithm, without the need for imaging. Of these patients, 38 (2.3%; 95% confidence interval [CI], 1.7-3.2) were diagnosed with a symptomatic PE at initial testing or during the 3-month follow-up. On further analysis, 36 patients out of these 38 patients had a positive age-adjusted D-dimer. The risk of venous thromboembolic events among the 414 patients with a D-dimer <1000 ng/mL but above the age-adjusted D-dimer cut-off was 36 of 414 (8.7%; 95% CI, 6.4-11.8). We provide external validation of the PEGeD algorithm in an independent cohort. Compared with standard algorithms, the PEGeD decreased the number of CTPA examinations. However, caution is required in patients with a low C-PTP and a D-dimer <1000 ng/mL but above their age-adjusted D-dimer cut-off.

Enoxaparin versus Placebo to Prevent Symptomatic Venous Thromboembolism in Hospitalized Older Adult Medical Patients

Enoxaparin to Prevent Venous Thromboembolism in Older AdultsThis trial of thromboprophylaxis in medically ill, hospitalized older adults did not demonstrate that enoxaparin reduced the risk of symptomatic VTE after 1 month. Because the trial was prematurely discontinued, larger trials are needed to definitively address this question.

Noninvasive diagnostic work-up for suspected acute pulmonary embolism during pregnancy: a systematic review and meta-analysis of individual patient data

BACKGROUND

Few studies evaluated the performance of noninvasive diagnostic strategies for suspected acute pulmonary embolism (PE) in pregnant women.

OBJECTIVES

The aim of this study was to establish the safety and efficiency of the Wells rule with fixed and adapted D-dimer threshold, and the YEARS algorithm, combined with compression ultrasonography (CUS), in pregnant women with suspected PE in an individual patient data meta-analysis.

METHODS

We performed a systematic review to identify prospective diagnostic management studies in pregnant women with suspected PE. Primary outcomes were safety, defined as the failure rate, ie, the 3-month venous thromboembolism (VTE) incidence after excluding PE without chest imaging, and efficiency, defined as the proportion of patients in whom chest imaging could be avoided.

RESULTS

We identified 2 relevant studies, of which individual patient-level data were analyzed in a fixed-effect meta-analysis, totaling 893 pregnant women. The Wells rule with fixed and adapted D-dimer threshold as well as the YEARS algorithm could safely rule out acute PE (failure rate, 0·37%-1·4%), but efficiency improved considerably when applying pretest probability-adapted D-dimer thresholds. The efficiency of bilateral CUS was limited (2·3% overall; number needed to test 43), especially in patients without symptoms of deep-vein thrombosis (efficiency 0·79%; number needed to test 127).

CONCLUSION

This study supports the latest guideline recommendations (European Society of Cardiology 2019) to apply pretest probability assessment and D-dimer tests to rule out PE in pregnant women. From an efficiency perspective, the use of a strategy with pretest probability-adapted D-dimer threshold is preferred. The yield of CUS was very limited in patients without concomitant symptoms of deep-vein thrombosis.

Enoxaparin for outpatients with COVID-19: 90-day results from the randomised, open-label, parallel-group, multinational, phase III OVID trial

INTRODUCTION

The benefits of early thromboprophylaxis in symptomatic COVID-19 outpatients remain unclear. We present the 90-day results from the randomised, open-label, parallel-group, investigator-initiated, multinational OVID phase III trial.

METHODS

Outpatients aged 50 years or older with acute symptomatic COVID-19 were randomised to receive enoxaparin 40 mg for 14 days once daily vs. standard of care (no thromboprophylaxis). The primary outcome was the composite of untoward hospitalisation and all-cause death within 30 days from randomisation. Secondary outcomes included arterial and venous major cardiovascular events, as well as the primary outcome within 90 days from randomisation. The study was prematurely terminated based on statistical criteria after the predefined interim analysis of 30-day data, which has been previously published. In the present analysis, we present the final, 90-day data from OVID and we additionally investigate the impact of thromboprophylaxis on the resolution of symptoms.

RESULTS

Of the 472 patients included in the intention-to-treat population, 234 were randomised to receive enoxaparin and 238 no thromboprophylaxis. The median age was 57 (Q1-Q3: 53-62) years and 217 (46 %) were women. The 90-day primary outcome occurred in 11 (4.7 %) patients of the enoxaparin arm and in 11 (4.6 %) controls (adjusted relative risk 1.00; 95 % CI: 0.44-2.25): 3 events per group occurred after day 30. The 90-day incidence of cardiovascular events was 0.9 % in the enoxaparin arm vs. 1.7 % in controls (relative risk 0.51; 95 % CI: 0.09-2.75). Individual symptoms improved progressively within 90 days with no difference between groups. At 90 days, 42 (17.9 %) patients in the enoxaparin arm and 40 (16.8 %) controls had persistent respiratory symptoms.

CONCLUSIONS

In adult community patients with COVID-19, early thromboprophylaxis with enoxaparin did not improve the course of COVID-19 neither in terms of hospitalisation and death nor considering COVID-19-related symptoms.

[Hospital mechanical thromboprophylaxis]

Mechanical thromboprophylaxis is an important part of hospital prevention of venous thromboembolism. It comprises graduated compression stockings and intermittent pneumatic compression. In this review, we summarize its physiological effect on venous hemodynamics, recent clinical studies that offer contrasting results, and discuss its utility in contemporary clinical practice. Mechanical thromboprophylaxis is currently suggested in patients at high thrombotic and hemorrhagic risk, favoring intermittent pneumatic compression, but does not seem useful in addition to pharmacological thromboprophylaxis.

Risk of neonatal hypothyroidism in newborns from mothers exposed to CTPA during pregnancy: Ancillary data from a prospective outcome study

BACKGROUND

Neonatal hypothyroidism is often raised as a potential concern for the use of computed tomography pulmonary angiography (CTPA) in pregnant women with suspected pulmonary embolism (PE).

OBJECTIVES

To assess the incidence of neonatal hypothyroidism among newborns from mothers exposed to CTPA.

PATIENTS/METHODS

Pregnant women with clinically suspected PE were included in a multicenter, multinational prospective diagnostic management outcome study, based on pretest clinical probability assessment, high-sensitivity D-dimer testing, bilateral lower limb venous compression ultrasonography, and CTPA. Results of Guthrie tests were systematically collected for newborns of all women who required CTPA as part of the diagnostic strategy. A thyroid-stimulating hormone (TSH) level above 15 U/ml was used to define hypothyroidism.

RESULTS

Out of the 166 women included in the Swiss participating centers, 149 underwent a CTPA including 14 with twin pregnancies. Eight women suffered a pregnancy loss and results of the Guthrie test could not be retrieved for four newborns. All TSH levels were reported as being below 15 U/ml. The incidence of neonatal hypothyroidism was 0/151 (0.0%, 95% confidence interval: 0.0%-2.5%).

CONCLUSIONS

We did not identify any cases of neonatal hypothyroidism in our cohort of 149 pregnant women investigated for suspected PE using a CTPA. Along with previous literature data, this provides further reassuring data regarding the use of CTPA in this indication.

Development of an international standard set of outcome measures for patients with venous thromboembolism: an International Consortium for Health Outcomes Measurement consensus recommendation

The International Consortium for Health Outcomes Measurement assembled an international working group of venous thromboembolism experts and patient representatives to develop a standardised minimum set of outcomes and outcome measurements for integration into clinical practice and potentially research to support clinical decision making and benchmarking of quality of care. 15 core outcomes important to patients and health-care professionals were selected and categorised into four domains: patient-reported outcomes, long term consequences of the disease, disease-specific complications, and treatment-related complications. The outcomes and outcome measures were designed to apply to all patients with venous thromboembolism aged 16 years or older. A measurement tool package was selected for inclusion in the core standard set, with a minimum number of items to be measured at predefined timepoints, which capture all core outcomes. Additional measures can be introduced to the user by a cascade opt-in system that allows for further assessment if required. This set of outcomes and measurement tools will facilitate the implementation of the use of patient-centred outcomes in daily practice.

Enoxaparin for primary thromboprophylaxis in symptomatic outpatients with COVID-19 (OVID): a randomised, open-label, parallel-group, multicentre, phase 3 trial

Background

COVID-19 is a viral prothrombotic respiratory infection. Heparins exert antithrombotic and anti-inflammatory effects, and might have antiviral properties. We aimed to investigate whether thromboprophylaxis with enoxaparin would prevent untoward hospitalisation and death in symptomatic, but clinically stable outpatients with COVID-19.

Methods

OVID was a randomised, open-label, parallel-group, investigator-initiated, phase 3 trial and was done at eight centres in Switzerland and Germany. Outpatients aged 50 years or older with acute COVID-19 were eligible if they presented with respiratory symptoms or body temperature higher than 37·5°C. Eligible participants underwent block-stratified randomisation (by age group 50–70 vs >70 years and by study centre) in a 1:1 ratio to receive either subcutaneous enoxaparin 40 mg once daily for 14 days versus standard of care (no thromboprophylaxis). The primary outcome was a composite of any untoward hospitalisation and all-cause death within 30 days of randomisation. Analysis of the efficacy outcomes was done in the intention-to-treat population. The primary safety outcome was major bleeding. The study was registered in ClinicalTrials.gov (NCT04400799) and has been completed.

Findings

At the predefined formal interim analysis for efficacy (50% of total study population), the independent Data Safety Monitoring Board recommended early termination of the trial on the basis of predefined statistical criteria having considered the very low probability of showing superiority of thromboprophylaxis with enoxaparin for the primary outcome under the initial study design assumptions. Between Aug 15, 2020, and Jan 14, 2022, from 3319 participants prescreened, 472 were included in the intention-to-treat population and randomly assigned to receive enoxaparin (n=234) or standard of care (n=238). The median age was 57 years (IQR 53–62) and 217 (46%) were women. The 30-day risk of the primary outcome was similar in participants allocated to receive enoxaparin and in controls (8 [3%] of 234 vs 8 [3%] of 238; adjusted relative risk 0·98; 95% CI 0·37–2·56; p=0·96). All hospitalisations were related to COVID-19. No deaths were reported during the study. No major bleeding events were recorded. Eight serious adverse events were recorded in the enoxaparin group versus nine in the control group.

Interpretation

These findings suggest thromboprophylaxis with enoxaparin does not reduce early hospitalisations and deaths among outpatients with symptomatic COVID-19. Futility of the treatment under the initial study design assumptions could not be conclusively assessed owing to under-representation of older patients and consequent low event rates.

Funding

SNSF (National Research Programme COVID-19 NRP78: 198352), University Hospital Zurich, University of Zurich, Dr-Ing Georg Pollert (Berlin), Johanna Dürmüller-Bol Foundation.

A systematic review of biomarkers among hospitalized patients with COVID-19 predictive of venous thromboembolism: A communication from the Predictive and Diagnostic Variables Scientific and Standardization Committee of the ISTH

Background

Thrombosis is reported to occur more often among patients with COVID‐19 than otherwise expected in the setting of viral pneumonia and sepsis. Systemic inflammatory biomarkers may be associated with venous thromboembolism (VTE) risk. The ISTH subcommittee on Predictive and Diagnostic Variables in Thrombotic Disease aimed to report the evidence on prognostic biomarkers for VTE in hospitalized patients with COVID‐19.

Methods

Using a standardized Preferred Reporting Items for Systematic Reviews and Meta‐analysis methodology, we conducted a systematic literature review to identify studies reporting prognostic biomarkers for VTE among hospitalized patients with COVID‐19. Eligible studies included adults hospitalized with COVID‐19 and reported the prognostic associations between any biomarker measured on admission, and the subsequent diagnosis of deep vein thrombosis or pulmonary embolism. Two authors reviewed titles and abstracts, and three authors extracted study data and performed review of bias. Results were displayed descriptively. Meta‐analysis was not possible.

Results

From the initial 196 identified studies, full‐text review was performed for 72 studies. Admission D‐dimer levels were associated with VTE during hospitalization in five studies, and elevated platelet count was associated with VTE during hospitalization in one study. The risk of bias ranged from low to high for included studies. Overall, there was a paucity of high‐quality prognostic studies. Studies on other biomarkers did not meet the systematic review inclusion criteria.

Conclusions

Admission D‐dimer was associated with VTE diagnosis during hospitalization for COVID‐19; however, prospective validation of this finding is needed to identify optimal D‐dimer thresholds to guide VTE prophylaxis measures.

Diagnostic Management of Pregnant Women With Suspected Pulmonary Embolism

Pulmonary embolism (PE) is one of the most common causes of severe morbidity and mortality during pregnancy. PE diagnosis during pregnancy remains a true challenge for all physicians, as many of the symptoms and signs associated with PE are often reported during physiological pregnancy. The fear of missing a PE during pregnancy leads a low threshold of suspicion, hence to a low prevalence of confirmed PE among pregnant women with suspected PE. This means that most pregnant women with suspected PE do not have the disease. Until recently, international guidelines suggested thoracic imaging in all pregnant women with suspected PE. Two recent prospective management outcome studies based on clinical probability assessment, D-dimer measurement, venous compression ultrasonography of the lower limbs (CUS) and computed tomography pulmonary angiography (CTPA) proved the safety of such strategies, with a very low failure rate. For the first time, these studies also demonstrated that the association of a clinical prediction rule and D-dimer measurement allowed a safe exclusion of PE in a significant proportion of pregnant women, without the need for radiating imaging tests. These two prospective studies pave the way to further improvements in the diagnostic strategies. Indeed, both specific clinical prediction rules and possibly D-dimer cutoffs adapted to pregnant women could help to further reduce the proportion of patients needing thoracic imaging. As an imaging test will still ultimately be necessary in a significant proportion of women, further technical advances in CT scans protocols could reduce the radiation dose to both the fetus and the mother, an important step to reassure clinicians. Finally, educational efforts should be encouraged in the future to pass the challenge of implementing these validated diagnostic strategies in everyday clinical practice.

[Hemodynamic and cardiovascular implications of arteriovenous fistulas in hemodialysis]

Arteriovenous fistula (AVF) remains the vascular access of choice in hemodialysis but generates cardiovascular constraints. Its creation immediately induces an increase in cardiac output. Increased venous return and subsequent volume overload lead to biventricular remodeling, and eventually to dysfunction. High-output heart failure (HOHF) caused by high-flow AVF is a recognized but not strictly defined clinical entity, based on the combination of hypervolemia with an elevated cardiac output. A Qa greater than 2 L/min is a risk factor for HOHF, particularly in susceptible patients. The most used flow reduction procedure is post-anastomotic vein caliber reduction by a banding technique, relieving symptoms and partially reversing previously induced structural abnormalities, but the benefit often remains limited in time.

Diagnostic de l’embolie pulmonaire dans le contexte de la grossesse

Les problématiques posées par la prise en charge de la femme enceinte suspecte d’embolie pulmonaire (EP) aux urgences sont multiples. Les modifications physiologiques au cours de la grossesse majorent les sollicitations médicales pour des tableaux de douleur thoracique, de dyspnée, de malaise… En parallèle, ces manifestations aux cours de la grossesse peuvent se confondre avec les éléments évocateurs d’une EP et interférer sur nos capacités d’appréciation de sa probabilité. Enfin, l’élévation physiologique des D-dimères et le taux d’imageries thoraciques non conclusives complexifient la démarche diagnostique. C’est pourtant dans le contexte de la grossesse qu’il est particulièrement souhaitable de ne pas manquer un diagnostic d’EP, tout en évitant d’exposer inutilement la patiente et son foetus à l’imagerie thoracique. Pour aider dans les prises de décision, deux stratégies ont été validées dans le contexte de la grossesse. La première repose sur le score de Genève, incluant la réalisation d’une échographie de compression proximale chez les patientes à probabilité forte ou ayant un D-dimère supérieur à 500 μg/L. La seconde repose sur l’algorithme YEARS, avec réalisation d’une échographie uniquement chez les patientes ayant des symptômes évocateurs d’une thrombose veineuse des membres inférieurs associée, puis un dosage des D-dimères avec un seuil à 500 ou 1 000 μg/L en fonction de la probabilité clinique. La fiabilité de ces deux stratégies a été démontrée. La première stratégie présente l’avantage de ne reposer que sur des données objectives, et la deuxième de reposer le seuil décisionnel à 1 000 μg/L chez les patientes n’ayant aucun des critères YEARS.

Safety and Efficiency of Diagnostic Strategies for Ruling Out Pulmonary Embolism in Clinically Relevant Patient Subgroups : A Systematic Review and Individual-Patient Data Meta-analysis

BACKGROUND

How diagnostic strategies for suspected pulmonary embolism (PE) perform in relevant patient subgroups defined by sex, age, cancer, and previous venous thromboembolism (VTE) is unknown.

PURPOSE

To evaluate the safety and efficiency of the Wells and revised Geneva scores combined with fixed and adapted D-dimer thresholds, as well as the YEARS algorithm, for ruling out acute PE in these subgroups.

DATA SOURCES

MEDLINE from 1 January 1995 until 1 January 2021.

STUDY SELECTION

16 studies assessing at least 1 diagnostic strategy.

DATA EXTRACTION

Individual-patient data from 20 553 patients.

DATA SYNTHESIS

Safety was defined as the diagnostic failure rate (the predicted 3-month VTE incidence after exclusion of PE without imaging at baseline). Efficiency was defined as the proportion of individuals classified by the strategy as "PE considered excluded" without imaging tests. Across all strategies, efficiency was highest in patients younger than 40 years (47% to 68%) and lowest in patients aged 80 years or older (6.0% to 23%) or patients with cancer (9.6% to 26%). However, efficiency improved considerably in these subgroups when pretest probability-dependent D-dimer thresholds were applied. Predicted failure rates were highest for strategies with adapted D-dimer thresholds, with failure rates varying between 2% and 4% in the predefined patient subgroups.

LIMITATIONS

Between-study differences in scoring predictor items and D-dimer assays, as well as the presence of differential verification bias, in particular for classifying fatal events and subsegmental PE cases, all of which may have led to an overestimation of the predicted failure rates of adapted D-dimer thresholds.

CONCLUSION

Overall, all strategies showed acceptable safety, with pretest probability-dependent D-dimer thresholds having not only the highest efficiency but also the highest predicted failure rate. From an efficiency perspective, this individual-patient data meta-analysis supports application of adapted D-dimer thresholds.

PRIMARY FUNDING SOURCE

Dutch Research Council. (PROSPERO: CRD42018089366).

[Selected highlights in angiology and haemostasis for the year 2021]

Several topics among those that marked the year 2021 are discussed in this article. Factor XI represents an original target for new anticoagulants, and the first results of a phase 2 study of prophylaxis after knee replacement surgery are very promising. A real-life study confirms that the pulmonary embolism exclusion strategy using an age-adjusted D-dimer cut-off is safe and increases the diagnostic yield. Several studies of tranexamic acid provide further insight into the indications for its use and highlight some potential risks. Finally, the concerns regarding a potential risk of increased mortality related to paclitaxel-eluting technology used in lower limb revascularisation are questioned by the results of the latest trials.

Ruling out pulmonary embolism across different healthcare settings: A systematic review and individual patient data meta-analysis

BACKGROUND

The challenging clinical dilemma of detecting pulmonary embolism (PE) in suspected patients is encountered in a variety of healthcare settings. We hypothesized that the optimal diagnostic approach to detect these patients in terms of safety and efficiency depends on underlying PE prevalence, case mix, and physician experience, overall reflected by the type of setting where patients are initially assessed. The objective of this study was to assess the capability of ruling out PE by available diagnostic strategies across all possible settings.

METHODS AND FINDINGS

We performed a literature search (MEDLINE) followed by an individual patient data (IPD) meta-analysis (MA; 23 studies), including patients from self-referral emergency care (n = 12,612), primary healthcare clinics (n = 3,174), referred secondary care (n = 17,052), and hospitalized or nursing home patients (n = 2,410). Multilevel logistic regression was performed to evaluate diagnostic performance of the Wells and revised Geneva rules, both using fixed and adapted D-dimer thresholds to age or pretest probability (PTP), for the YEARS algorithm and for the Pulmonary Embolism Rule-out Criteria (PERC). All strategies were tested separately in each healthcare setting. Following studies done in this field, the primary diagnostic metrices estimated from the models were the "failure rate" of each strategy-i.e., the proportion of missed PE among patients categorized as "PE excluded" and "efficiency"-defined as the proportion of patients categorized as "PE excluded" among all patients. In self-referral emergency care, the PERC algorithm excludes PE in 21% of suspected patients at a failure rate of 1.12% (95% confidence interval [CI] 0.74 to 1.70), whereas this increases to 6.01% (4.09 to 8.75) in referred patients to secondary care at an efficiency of 10%. In patients from primary healthcare and those referred to secondary care, strategies adjusting D-dimer to PTP are the most efficient (range: 43% to 62%) at a failure rate ranging between 0.25% and 3.06%, with higher failure rates observed in patients referred to secondary care. For this latter setting, strategies adjusting D-dimer to age are associated with a lower failure rate ranging between 0.65% and 0.81%, yet are also less efficient (range: 33% and 35%). For all strategies, failure rates are highest in hospitalized or nursing home patients, ranging between 1.68% and 5.13%, at an efficiency ranging between 15% and 30%. The main limitation of the primary analyses was that the diagnostic performance of each strategy was compared in different sets of studies since the availability of items used in each diagnostic strategy differed across included studies; however, sensitivity analyses suggested that the findings were robust.

CONCLUSIONS

The capability of safely and efficiently ruling out PE of available diagnostic strategies differs for different healthcare settings. The findings of this IPD MA help in determining the optimum diagnostic strategies for ruling out PE per healthcare setting, balancing the trade-off between failure rate and efficiency of each strategy.

[COVID-19, anticoagulation and venous thromboembolism: what have we learned ?]

Severe COVID-19 is associated with venous thromboembolic events and and immuno-thrombotic phenomena, responsible for pulmonary vascular damage. This review summarizes the current knowledge on thrombotic risk in COVID-19 inpatients, the potential predictive factors (including D-dimer) and the randomized trials studying the effect of intermediate or therapeutic-dose anticoagulation on the clinical and thrombotic prognosis. Despite the initial hope, therapeutic anticoagulation does not improve the clinical prognosis in critically ill inpatients, and standard prophylactic anticoagulation is therefore recommended. In non-critical inpatients, the use of therapeutic anticoagulation may help reduce the risk of severe clinical deterioration, but its risk-benefit will be clarified in ongoing studies and meta-analyzes.

Management of high-risk pulmonary embolism in pregnancy

Pregnancy-associated high-risk pulmonary embolism (PE) is among the most frequent causes of maternal mortality in the Western world, by causing hemodynamic instability and circulatory failure through a large thrombotic pulmonary obstruction. The very challenging management of these dramatic situations comprises the need to quickly select a therapy of pulmonary reperfusion or hemodynamic replacement, while taking into account both maternal and fetal risks. In this review, we discuss the role of risk stratification in pregnancy-associated PE and the available evidence to support the use of thrombolysis, catheter-directed thrombectomy/thrombolysis, surgical embolectomy and extracorporeal membrane oxygenation. Despite the lack of comparative studies and solid evidence, most reported cases of high-risk pregnancy-associated PE have been treated with thrombolysis, with high maternal and fetal survivals, and thrombolysis is suggested by guidelines in life-threatening PE. For women in the peripartum and early post-partum period, non-fibrinolytic treatments may be preferred as a first-line treatment, if available, because of the particularly high bleeding risk. In all cases, pregnancy-associated high-risk PE requires a multidisciplinary approach involving PE response teams and obstetricians.

Proximal deep vein thrombosis and pulmonary embolism in COVID-19 patients: a systematic review and meta-analysis

BACKGROUND

COVID-19 appears to be associated with a high risk of venous thromboembolism (VTE). We aimed to systematically review and meta-analyze the risk of clinically relevant VTE in patients hospitalized for COVID-19.

METHODS

This meta-analysis included original articles in English published from January 1st, 2020 to June 15th, 2020 in Pubmed/MEDLINE, Embase, Web of science, and Cochrane. Outcomes were major VTE, defined as any objectively diagnosed pulmonary embolism (PE) and/or proximal deep vein thrombosis (DVT). Primary analysis estimated the risk of VTE, stratified by acutely and critically ill inpatients. Secondary analyses explored the separate risk of proximal DVT and of PE; the risk of major VTE stratified by screening and by type of anticoagulation.

RESULTS

In 33 studies (n = 4009 inpatients) with heterogeneous thrombotic risk factors, VTE incidence was 9% (95%CI 5-13%, I2 = 92.5) overall, and 21% (95%CI 14-28%, I2 = 87.6%) for patients hospitalized in the ICU. Proximal lower limb DVT incidence was 3% (95%CI 1-5%, I2 = 87.0%) and 8% (95%CI 3-14%, I2 = 87.6%), respectively. PE incidence was 8% (95%CI 4-13%, I2 = 92.1%) and 17% (95%CI 11-25%, I2 = 89.3%), respectively. Screening and absence of anticoagulation were associated with a higher VTE incidence. When restricting to medically ill inpatients, the VTE incidence was 2% (95%CI 0-6%).

CONCLUSIONS

The risk of major VTE among COVID-19 inpatients is high but varies greatly with severity of the disease. These findings reinforce the need for the use of thromboprophylaxis in all COVID-19 inpatients and for clinical trials testing different thromboprophylaxis regimens in subgroups of COVID-19 inpatients.

TRIAL REGISTRATION

The review protocol was registered in PROSPERO International Prospective Register of Systematic Reviews ( CRD42020193369 ).

[Towards new indications for direct oral anticoagulants]

Direct oral anticoagulants (DOAC) represent commonly prescribed drugs in everyday clinical practice for indications such as atrial fibrillation, prevention of venous thromboembolic disease (VTE) after major orthopaedic surgery, treatment of deep vein thrombosis and pulmonary embolism, and long term prevention of VTE recurrence. More recently, the efficacy of DOAC has been demonstrated in new clinical situations, such as heparin-induced thrombocytopenia, cancer-associated VTE and secondary prevention of cardiovascular events in patients with atherothrombotic arterial disease. This article's aims is to present the recent data on which these new indications are based.

[Evolution of thromboprophylaxis after hip and knee arthroplasties]

Venous thrombotic events frequently complicate major elective arthroplasties such as hip and knee replacements. The risk of proximal deep vein thrombosis and pulmonary embolism is estimated at 5 %. For decades, the use of low-dose heparins for up to 5 weeks post-surgery has helped to reduce the risk of thrombotic complications. In this narrative review, we describe the evidence supporting the use of direct oral anticoagulants (in Switzerland - rivaroxaban and apixaban), whose risk-benefit ratios appears superior to that of heparins, at a lower cost. Hybrid strategies combining a short-term anticoagulant followed by low-dose aspirin are also recommended for patients deemed at low thrombotic risk.

[Diagnosis and management of pulmonary embolism : some reflections on the latest ESC guidelines]

The latest recommendations from the European Society of Cardiology (ESC) on the diagnostic and therapeutic management of pulmonary embolism (PE) published this year provide an important update compared to the 2014 version. In terms of diagnosis, the use of the age-adjusted D-dimer cutoff is currently suggested, and a diagnostic algorithm for suspected PE during pregnancy is proposed. Detailed recommendations are provided for the initial orientation of patients with acute PE based on prognostic stratification criteria, as well as for clinical follow-up after PE. Finally, direct oral anticoagulants are included as therapeutic options for the treatment of cancer-associated thrombosis.

[Digital ischemia: a diagnostic challenge]

Digital ischemia is suspected in presence of a cold, pale or cyanotic and painful finger. It is a diagnostic and therapeutic emergency and needs urgent referral to a vascular specialist. Digital pressure measurement is needed to confirm the diagnosis. A thorough history taking and physical examination help to guide patients' management. Antithrombotic therapy - with an antiplatelet or anticoagulant drug depending on the most likely etiology - need to be introduced without delay, while awaiting the results of the individualized etiologic workup. Hospital admission is often necessary. A prompt diagnostic and therapeutic management allows satisfactory pain control and avoidance of irreversible digital lesions in the majority of cases.

External validation of the YEARS diagnostic algorithm for suspected pulmonary embolism

BACKGROUND

Validated diagnostic algorithms are used to manage patients with suspected pulmonary embolism (PE). The recently published YEARS study proposed a simplified diagnostic strategy to reduce the use of computed tomography pulmonary angiography.

OBJECTIVES

To externally validate this strategy in an independent cohort.

METHODS

We analyzed data from three previous prospective cohort studies of outpatients with suspected PE. We retrospectively applied the YEARS algorithm. The three YEARS clinical criteria are: clinical signs of deep vein thrombosis, hemoptysis, and PE as the most likely diagnosis. If zero YEARS criteria are met, a D-dimer < 1000 ng/mL will rule out PE. If ≥1 YEARS criteria are met, a D-dimer < 500 ng/mL will rule out PE.

RESULTS

Of the 3314 patients, 731 (22.1%) had PE. Applying the YEARS diagnostic algorithm, 1423 (42.9%) patients could have had PE ruled out without imaging. Of these patients, 17 (1.2%; 95% confidence interval 0.8-1.9) were diagnosed with PE at initial testing. All 17 had no YEARS item and a D-dimer < 1000 ng/mL. All 17 had a D-dimer level above their age-adjusted cutoff. Among the 272 patients with no YEARS criteria and a D-dimer < 1000 ng/mL but above their age-adjusted D-dimer cutoff, PE was diagnosed in 6.3% (17/272; 95% confidence interval 3.9-9.8).

CONCLUSION

We provide external validation of the YEARS diagnostic algorithm in an independent cohort. The rule appears to safely exclude PE. However, caution is required in patients with no YEARS item and a D-dimer < 1000 ng/mL but above their age-adjusted D-dimer cutoff.

Ventilation/perfusion SPECT for the diagnosis of pulmonary embolism: A systematic review

BACKGROUND

Ventilation/perfusion (V/Q) single-photon emission computed tomography (SPECT) has largely replaced conventional planar V/Q scan in nuclear medicine departments for pulmonary embolism (PE) diagnosis. However, the diagnostic performance of the test and its role in the diagnostic management of acute PE are still a matter of debate.

OBJECTIVE

The primary aim was to establish the diagnostic accuracy (sensitivity, specificity) of V/Q SPECT for PE diagnosis. The secondary aim was to review the clinical outcomes of patients investigated for PE suspicion with a standardized algorithm based on V/Q SPECT.

METHODS

We conducted a systematic review of diagnostic accuracy and management outcome studies involving patients evaluated with V/Q SPECT for suspected acute PE. We searched from inception to June 23, 2020, MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials for diagnostic accuracy studies, randomized controlled trials, and observational cohort studies. The methodological quality and risk of bias of eligible studies were assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) and the Risk of Bias in Nonrandomized Studies of Interventions tools.

RESULTS

We identified 13 accuracy studies and one prospective outcome study. Eleven diagnostic accuracy studies were deemed at high risk of bias in at least two of the four domains of QUADAS-2 evaluation and a further two studies raised concerns regarding the applicability of results, precluding the meta-analysis for accuracy indices. The only prospective cohort study demonstrated critical risk of bias.

CONCLUSIONS

Although V/Q SPECT has been widely implemented in daily clinical practice, the exact diagnostic performance of V/Q SPECT for PE is still unknown. This systematic review clearly identifies knowledge gaps and sets the agenda for future research.

Venous thromboembolism in COVID-19: systematic review of reported risks and current guidelines

AIMS OF THE STUDY

Many centres have noticed a high number of venous thromboembolism (VTE) events among critically ill inpatients with COVID-19 pneumonia. The aims of this study were (1) to summarise the reported risk of VTE associated with COVID-19 infections and (2) to summarise guidance documents on thromboprophylaxis in COVID-19 patients, in a systematic review.

METHODS

We systematically searched for peer-reviewed evidence on the risk of VTE in patients with COVID-19, in PubMed, Embase and Twitter, and for guidelines or guidance documents for thromboprophylaxis, from international or national societies relevant to the field of thrombosis and haemostasis, up to April 30 2020.

RESULTS

We found 11 studies (1 clinical trial, 7 retrospective cohorts and 3 prospective cohorts), which included a range of 16 to 388 in patients with COVID-19 (total of 1369 inpatients). The diagnoses of COVID-19 and VTE were of high quality, but the follow-up was often unclear. Most studies reported universal in-hospital thromboprophylaxis. Among all inpatients and among intensive care unit (ICU) inpatients with COVID-19, reported risks of VTE were 4.4&ndash;8.2% (three studies) and 0&ndash;35.3% (six studies), respectively. Two studies at least partially screened for VTE in ICU inpatients with COVID-19, and found risks of 24.7&ndash;53.8%. We found 12 guidelines for thromboprophylaxis of COVID-19 patients. The majority suggested universal pharmacological thromboprophylaxis in all COVID-19 inpatients, but there was heterogeneity in the suggested intensity of thromboprophylaxis: seven advised considering intensified doses of heparin according to the clinical or biological severity of the disease, especially in the ICU setting.

CONCLUSIONS

Venous thromboembolism very commonly complicates the clinical course of inpatients with COVID-19, despite thromboprophylaxis. The risk appears highest among critically ill inpatients. We found no estimates of risks among outpatients. Many questions remain unresolved, as delineated by the heterogeneity of national and international guidelines. This situation calls for fast randomised clinical trials, comparing different schemes of thromboprophylaxis in COVID-19 inpatients.

[Venous thrombotic risk related to SARS-CoV-2 : prevalence, recommendations and perspectives]

Since the SARS-CoV-2 pandemic outbreak, growing evidence suggests that patients suffering from COVID-19 are at increased risk of thrombotic events. The sepsis-related activation of the coagulation combined with a high prevalence of common thrombotic risk factors could contribute to this prothrombotic state. Coagulation biomarkers could help in the identification of patients at risk of complications and mortality. The incidence of venous thromboembolic events appears to be increased, especially in severe COVID-19 patients. Based on that knowledge, several societies have provided recommendation on the prevention of venous thromboembolism. In this narrative review, we summarize available epidemiologic data on venous thromboembolism and recommendations on thromboprophylaxis in COVID-19.

Long-term risk of postthrombotic syndrome after symptomatic distal deep vein thrombosis: The CACTUS-PTS study

BACKGROUND

After a proximal lower limb deep vein thrombosis (DVT; involving popliteal veins or above), up to 40% of patients develop postthrombotic syndrome (PTS) as assessed by the Villalta scale (VS). Poor initial anticoagulant treatment is a known risk factor for PTS. The risk of developing PTS after isolated distal DVT (infra-popliteal DVT without pulmonary embolism), and the impact of anticoagulant treatment on this risk, are uncertain.

METHODS

Long-term follow-up of CACTUS double-blind trial comparing 6 weeks of s.c. nadroparin (171 IU/kg/d) versus s.c. placebo for a first symptomatic isolated distal DVT. At least 1 year after randomization, patients had a PTS assessment in clinic or by phone using the VS.

RESULTS

After a median follow-up of 6 years, PTS was present in 30% (n = 54) of the 178 patients who had a PTS assessment. PTS was moderate or severe in 24% (n = 13) of cases. There was no statistically significant difference in prevalence of PTS in the nadroparin versus placebo groups (29% versus 32%, P = .6), except in patients without evidence of primary chronic venous insufficiency (9% versus 24%, P = .04). Rates of venous thromboembolism recurrence during follow-up in the nadroparin and placebo groups were, respectively, 8% (n = 7) and 14% (n = 13; P = .2).

CONCLUSION

After a first isolated distal DVT, the risk of PTS is substantial but much lower than that reported after proximal DVT. Anticoagulation with nadroparin doesn't provide any clear benefit to prevent PTS, except in patients without preexisting chronic venous insufficiency. Anticoagulation might be associated with a lower risk of venous thromboembolism recurrence.

Age-adjusted D-dimer cutoff for the diagnosis of pulmonary embolism: A cost-effectiveness analysis

BACKGROUND

In patients with suspected pulmonary embolism (PE) and a non-high pretest probability, the use of an age-adjusted D-dimer cutoff (AADD, <500 ng/mL up to 50 years, then

METHODS

We created a decision tree to compare the use of the AADD with the standard D-dimer cutoff. The model included short-term venous thromboembolism-related events and long-term complications, their associated morbidity/mortality, and costs. Probabilities were derived from published literature and the ADJUST-PE study, and costs from US estimates. The time horizon was lifetime, with a health care system perspective.

RESULTS

Using the AADD cutoff, compared with the standard cutoff, was associated with a loss of 0.0001 quality-adjusted life-years (QALY) and an average cost reduction of $33.4. The decremental cost-effectiveness ratio (DCER) was +$282 881/lost QALY (95% confidence interval from +$43 209/lost QALY to a dominant strategy). The probability that the use of the AADD cutoff was either dominant or gained >$200 000/lost QALY was 79.4%. In sensitivity analyses, the DCER became <+$200 000/lost QALY only if, among patients with D-dimer below the AADD cutoff, the mortality of an undiagnosed PE was >6% or the prevalence of PE was >0.6%.

CONCLUSIONS

The AADD cutoff results in a clinically nonsignificant decrease in QALY but important costs reductions. It is a decrementally cost-effective innovation, with a potential of cost savings of >$80 million per year for the United States health care system.

Collapse

Key Words

• biomarker
• cost-benefit analysis
• diagnosis
• fibrin fragment D
• pulmonary embolism

Collapse

MESH Headings

• Angiography
• Cost-Benefit Analysis
• Fibrin Fibrinogen Degradation Products
• Humans
• Pulmonary Embolism/diagnosis

Collapse

Grants Collapse

Affiliation(s)

Marc Blondon Division of Angiology and Haemostasis, Faculty of Medicine and Geneva University Hospitals, Geneva, Switzerland
Gregoire Le Gal Department of Medicine, Ottawa Hospital Research Institute, University of Ottawa, ON, Canada
Guy Meyer Department of Respiratory Disease, Hôpital Européen Georges Pompidou, APHP, Paris, France Université Paris Descartes, Paris, France
Marc Righini Division of Angiology and Haemostasis, Faculty of Medicine and Geneva University Hospitals, Geneva, Switzerland
Helia Robert-Ebadi Division of Angiology and Haemostasis, Faculty of Medicine and Geneva University Hospitals, Geneva, Switzerland

Collapse

Preventing Venous Thromboembolism in Ambulatory Patients with Cancer: A Narrative Review

Venous thromboembolism (VTE) is frequent among patients with cancer. Ambulatory cancer patients starting chemotherapy have a 5% to 10% risk of cancer associated thrombosis (CAT) within the first year after cancer diagnosis. This risk may vary according to patient characteristics, cancer location, cancer stage, or the type of chemotherapeutic regimen. Landmark studies evaluating thrombophrophylaxis with low molecular weight heparin (LMWH) for ambulatory cancer patients have shown a relative reduction in the rate of symptomatic VTE of about one half. However, the absolute risk reduction is modest among unselected patients given a rather low risk of events resulting in a number needed to treat (NNT) of 40 to 50. Moreover, this modest benefit is mitigated by a trend towards an increased risk of bleeding, and the economic and patient burden due to daily injections of LMWH. For these reasons, routine thromboprophylaxis is not recommended by expert societies. Advances in VTE risk stratification among cancer patients, and growing evidence regarding efficacy and safety of direct oral anticoagulants (DOACs) for the treatment and prevention of CAT have led to reconsider the paradigms of this risk–benefit assessment. This narrative review aims to summarize the recent evidence provided by randomized trials comparing DOACs to placebo in ambulatory cancer patients and its impact on expert recommendations and clinical practice.

External validation of the simplified Geneva risk assessment model for hospital-associated venous thromboembolism in the Padua cohort

BACKGROUND

The simplified Geneva risk assessment model (RAM) predicts the risk of hospitalization-related venous thromboembolism (VTE) in medical inpatients in its developmental cohort but has not been validated.

OBJECTIVES

To externally validate the simplified Geneva RAM.

PATIENTS/METHODS

For this secondary analysis of a prospective cohort set in Padua, we calculated the simplified Geneva RAM for all participants. They were followed up for 90 days for the occurrence of adjudicated VTE. Thirty- and 90-day risks of VTE were estimated by the Kaplan-Meier method, and categories of risks compared with a Cox regression model adjusted for the use of thromboprophylaxis.

RESULTS

Among 1180 medical inpatients, the 90-day risk of symptomatic VTE was 3.1%. The simplified Geneva RAM classified 56.9% as high risk (≥3 points; 90-day risk of VTE of 5.2%) and 43.1% as low risk (<3 points; 90-day risk of VTE of 0.4%). Compared with low-risk participants, high-risk participants had an 18-fold greater risk of VTE than low-risk participants (hazard ratio [HR] 17.9, 95% confidence interval [CI] 4.3-74.7). A very high-risk category (≥7 points) identified 5.3% of participants with a 9.5% probability of VTE at 90 days.

CONCLUSIONS

In this external validation study, we confirm the excellent discrimination and clinically adequate calibration of the simplified Geneva RAM as a stratification tool to guide the use of thromboprophylaxis.

[Direct oral anticoagulants in the treatment of cancer-associated thrombosis]

The use of direct oral anticoagulants (DOACs) has been largely -implemented in the management of venous thromboembolic disease in non-cancer patients. In cancer-associated thrombosis, low molecular weight heparins (LMWHs) and especially dalteparin have long been the reference standard therapy. Following the publication of two randomised trials comparing edoxaban and rivaroxaban to -dalteparin, DOACs now represent an alternative with an interesting efficacy and safety profile. Moreover, they offer the comfort of an oral administration and a lower cost. In patients with gastrointestinal or genitourinary cancers however, a higher bleeding risk has been shown with DOACs. LMWHs thus remain the treatment of choice in this group of patients.

Avoiding disease mongering: A checklist for vascular physicians and researchers

Disease mongering is an expression created in 1992 by a medical journalist, Lynn Payer, to qualify the "selling of sickness that widens the boundaries of treatable illness in order to expand markets for those who sell and deliver treatments". This interesting concept led us to question whether, as researchers with publication and career interests in superficial vein thrombosis, we were not shaping a benign condition into a disease. Since the publication of the CALISTO trial in 2010, anticoagulant management of superficial vein thrombosis remains debated. Issues raised, such as the cost-effectiveness of the treatment strategy, the use of a composite endpoint including death, the low event rate without mortality reduction and conflict of interest due to industrial funding. We searched Embase, Medline, Web of science, and Opengrey databases to review all aspects about disease mongering raised in the literature and created a checklist with seventeen items. We used this checklist as support for a narrative review, questioning known literature on superficial vein thrombosis. The main issues pointing towards disease mongering concerned definition and promotion; whereas management seemed rather spared. Many arguments could be counterbalanced, but researchers should pay particular attention to three major points: exaggeration of the severity of the disease and potential adverse outcomes without treatment, promotion by opinion leaders, and an openly declared, yet undoubtedly present, conflict of interest situation.

Could the YEARS algorithm be used to exclude pulmonary embolism during pregnancy? Data from the CT-PE-pregnancy study

INTRODUCTION

The recently proposed YEARS algorithm was shown to safely exclude pulmonary embolism (PE) and reduce the use of computed tomography pulmonary angiography (CTPA) among pregnant women with suspected PE. Our aim was to externally validate this finding.

METHODS

We performed a post hoc analysis of a prospective management outcome study for PE diagnosis in pregnant women. PE was diagnosed with an algorithm that combined the revised Geneva score, D-dimer testing, bilateral lower-limb compression ultrasonography, and CTPA. All women had a 3-month follow-up. All of the items necessary to use the YEARS algorithm were prospectively collected at the time of the study.

RESULTS

Of the 395 women included in the original study, 371 were available for the present analysis. The PE prevalence was 6.5%. Ninety-one women had no YEARS items, and 280 had one or more items. When the YEARS items were combined with D-dimer levels (<1000 ng/mL in women with no items, and <500 ng/mL in women with one or more items), 77 women (21%) met the criteria for PE exclusion and would not have undergone CTPA as per the YEARS algorithm. None of these 77 women had PE diagnosed during the initial work-up or 3-month follow-up. Therefore, the failure rate of the YEARS algorithm in our pregnant women population was 0/77 (95% confidence interval 0.0-3.9).

CONCLUSION

In our study, application of the YEARS algorithm would have resulted in safe exclusion of PE in one of five pregnant women without the need for radiation exposure, further supporting the use of the algorithm in this population.

Effect of anticoagulant treatment on pain in distal deep vein thrombosis: an ancillary analysis from the cactus trial

Essentials Management of patients with calf deep vein thrombosis remains controversial. We conducted a post-hoc analysis of a placebo controlled LMWH randomized clinical trial. Pain was assessed using visual analogue scale at inclusion, one and six weeks. There was no difference in pain control between the two arms. SUMMARY: Background The optimal management of distal deep vein thrombosis (DVT) is highly debated. The only available placebo-controlled trial suggested the absence of clear benefit of anticoagulation. Many physicians feel that, beyond preventing thromboembolic complications, anticoagulation with low-molecular-weight heparin (LMWH) has the potential to improve pain control. Objectives To analyze whether LMWHs decrease pain in patients with distal deep vein thrombosis. Patients and methods Two-hundred and fifty-two patients included in a multicenter, placebo-controlled, randomized clinical trial of LMWH in patients with acute distal DVT and who were asked to rate their pain at inclusion and at each medical visit, using a visual analogue pain scale (VAS). Results One hundred and thirty patients were randomized in the therapeutic nadroparin arm and 122 patients were randomized in the placebo arm. Mean VAS values were 4.6 (standard deviation [SD] 2.5) at inclusion, 2.1 (SD 2.0) at 1 week and 0.4 (SD 1.2) at 6 weeks. We calculated the individual variation in VAS between inclusion and 1 week in patients in whom VAS was available at the two study time-points. There was no difference in the mean VAS reduction between patients treated with therapeutic nadroparin (n = 106) and with placebo (n = 109): -2.6 (SD 2.4) vs. -2.3 (SD 2.0) after 1 week and -4.4 (SD 2.8) vs. -4.0 (SD 2.4) after 6 weeks, respectively. The use of compression stockings was associated with a reduction in pain. Conclusion These data suggests that LMWH use does not improve pain control as compared with placebo in patients with acute distal DVT.

[Diagnosis of pulmonary embolism]

The diagnosis of pulmonary embolism (PE) is nowadays based on the sequential use of several diagnostic tests rather than on a single test. These diagnostic strategies are safe and have been prospectively validated. The first step after identifying patients with suspicion of PE is to establish the pre-test clinical probability. Several scores are available in order to make a standardised and reproducible assessment of the clinical probability, and therefore represent precious diagnostic tools. Indeed, clinical probability guides further investigations. Indeed, in patients with a low or an intermediate clinical probability or an "unlikely" probability, PE can be safely ruled out by negative D-dimers in approximately one third of outpatients without additional imaging. In case of positive D-dimers and a high clinical probability or a "likely" clinical probability, CT pulmonary angiography is now the recommended imaging technique. However, lower limb venous compression ultrasound and ventilation/perfusion scans remain useful in patients with contra-indications to CT, mainly those with renal insufficiency. Finally, some novel diagnostic tests seem promising. For example, V/Q SPECT has arisen as a highly accurate test and a potential alternative to CTPA. However, prospective management outcome studies are still lacking and are warranted before its implementation in routine clinical practice.

Multiple arteriovenous malformations caused by RASA1 gene mutation presenting during pregnancy - a case report and review of the literature

Pregnancy can influence the development and progression of congenital arteriovenous malformations (AVM) and thus lead to life-threatening complications for the mother and fetus like high output cardiac failure and premature delivery. The simultaneous presence of a capillary malformation and AVM strongly suggests a RASA1 related disorder. Keywords: Arteriovenous malformations, capillary malformation-arteriovenous malformation, capillaries/abnormalities, port-wine stain, pregnancy, RASA1 protein.

[Arteriovenous malformations and its complex management]

Congenital arteriovenous malformations (AVM) represent a rare clinical entity. They are present at birth but can remain silent for many years. Due to their potential severity and their complex and specific management, the general practitioner should know when to suspect the presence of an AVM. Anatomic and hemodynamic characteristics of these malformations are well analysed by Doppler ultrasound, which is the first-line diagnostic test. MRI is often used in conjunction with ultrasound to better define the location and extension to neighbouring tissues and organs. Embolisation should be restricted to AVM associated with major functional disability, local complications or systemic cardiac complications in case of high flow volume life-threatening lesions.