Post-thrombotic syndrome: prevalence, prognostication and need for progress

Reduced incidence of vein occlusion and postthrombotic syndrome after immediate compression for deep vein thrombosis

Thus far, the association between residual vein occlusion and immediate compression therapy and postthrombotic syndrome is undetermined. Therefore, we investigated whether compression therapy immediately after diagnosis of deep vein thrombosis affects the occurrence of residual vein obstruction (RVO), and whether the presence of RVO is associated with postthrombotic syndrome and recurrent venous thromboembolism. In a prespecified substudy within the IDEAL (individualized duration of elastic compression therapy against long-term duration of therapy for prevention of postthrombotic syndrome) deep vein thrombosis (DVT) study, 592 adult patients from 10 academic and nonacademic centers across The Netherlands, with objectively confirmed proximal DVT of the leg, received no compression or acute compression within 24 hours of diagnosis of DVT with either multilayer bandaging or compression hosiery (pressure, 35 mm Hg). Presence of RVO and recurrent venous thromboembolism was confirmed with compression ultrasonography and incidence of postthrombotic syndrome as a Villalta score of at least 5 at 6 and 24 months. The average time from diagnosis until assessment of RVO was 5.3 (standard deviation, 1.9) months. A significantly lower percentage of patients who did receive compression therapy immediately after DVT had RVO (46.3% vs 66.7%; odds ratio, 0.46; 95% confidence interval, 0.27-0.80; P = .005). Postthrombotic syndrome was less prevalent in patients without RVO (46.0% vs 54.0%; odds ratio, 0.65; 95% confidence interval, 0.46-0.92; P = .013). Recurrent venous thrombosis showed no significant association with RVO. Immediate compression should therefore be offered to all patients with acute DVT of the leg, irrespective of severity of complaints. This study was registered at ClinicalTrials.gov (NCT01429714) and the Dutch Trial registry in November 2010 (NTR2597).

Contemporary outcomes of elective iliocaval and infrainguinal venous intervention for post-thrombotic chronic venous occlusive disease

BACKGROUND

Patients with iliofemoral deep venous thrombosis are at risk for development of post-thrombotic syndrome. Iliac vein stenting has been shown to significantly improve clinical outcomes in patients with venous outflow obstruction, although many studies include a heterogeneous population with several different venous pathologic processes. Our objective was to evaluate the results of iliocaval and infrainguinal venous intervention for venous outflow obstruction due to post-thrombotic chronic venous occlusive disease.

METHODS

All patients treated at a single institution for symptomatic iliocaval venous occlusive lesions with and without infrainguinal extension between 2008 and 2015 were retrospectively analyzed. Nonthrombotic iliac vein lesions were excluded from analysis. All patients with symptomatic post-thrombotic occlusion of the iliac vein or inferior vena cava (IVC) and a Clinical, Etiology, Anatomy, and Pathophysiology (CEAP) score of 3 or greater were included. Demographics of the patients, presence of IVC filters at presentation, presenting CEAP score, postintervention CEAP score, primary and secondary patency, wound healing and subjective clinical improvement outcomes, and procedural details were recorded in a database.

RESULTS

There were 105 patients with symptomatic iliocaval venous occlusive lesions identified, of which 31 patients (42 limbs) met inclusion criteria. Presenting symptoms included pain or swelling (100%); venous claudication (81%); and CEAP class 3 (76%), 4 or 5 (14%), or 6 (10%). All patients presented with either subacute (>30 days [35%]) or chronic (>90 days [65%]) iliocaval venous thrombosis. Procedural technical success with venous recanalization was achieved in 100% of cases and in 46% of IVC filter retrieval attempts. Overall clinical improvement was achieved in 84% of patients; complete clinical resolution was obtained in 42% and a decrease in CEAP score in 65%. At a mean follow-up of 14.7 months (range, 2-49 months), primary and secondary 1-year patency was 66% and 75% overall, and primary patency was equivalent between patients requiring isolated iliac venous stenting and those requiring infrainguinal stent extension (68% vs 65%, respectively; P = .74, not significant). Patients who presented with IVC filters had a higher rate of complete clinical resolution if the filter could be removed (100%) compared with those patients in whom the filter could not be removed (17%; P < .01).

CONCLUSIONS

Treatment of chronic venous occlusive disease with iliocaval and infrainguinal venous stenting is associated with acceptable 1-year patency rates, healing of venous ulcers, and a significant reduction in symptoms and CEAP score. Patients who underwent successful removal of indwelling IVC filters showed improved clinical outcomes compared with those in whom the IVC filter could not be removed.

Does Catheter-Directed Thrombolysis Prevent Postthrombotic Syndrome?

Purpose

The aim of this study is to identify risk factors of postthrombotic syndrome (PTS) and evaluate the efficacy of catheter-directed thrombolysis (CDT) for preventing the development of PTS in patients with lower extremity deep vein thrombosis (DVT).

Materials and Methods

From 2005 January to 2013 December, 139 limbs of 126 patients were included in this study who had the first episode of proximal DVT at the affected limb and who had visited our out-patient clinic. CDT was performed on 55 limbs (39.6%). We achieved complete recanalization in 39 limbs (70.9%) and partial recanalization (residual thrombus <50.0%) in 16 limbs (29.1%). We retrospectively reviewed medical records for possible predictors of PTS.

Results

Median follow-up duration was 83 months (range, 30–136 months). No differences were found between the CDT and non-CDT group in age, gender, duration of symptom, use of anticoagulation and recurrence of DVT. A significantly higher thrombotic burden was observed in the CDT group (P=0.009). In a binary logistic regression model, patients with PTS had significantly higher body mass index (BMI) (odds ratio [OR], 1.303; 95% confidence interval [CI], 1.079–1.574; P=0.006) and longer thrombotic burden involved in ilio-femoro-popliteal DVT (OR, 3.666; 95% CI, 1.093–12.296; P=0.035). CDT did not influence the risk of PTS (P>0.05).

Conclusion

We suggest that CDT is not effective in preventing PTS, while higher BMI and longer thrombotic burden are associated with the development of PTS in patients with DVT.

How I treat the postthrombotic syndrome

The postthrombotic syndrome (PTS) is a chronic complication of deep vein thrombosis (DVT) that imposes significant morbidity, reduces quality of life, and is costly. After DVT, 20% to 50% of patients will develop PTS, and up to 5% will develop severe PTS. The principal risk factors for PTS are anatomically extensive DVT, recurrent ipsilateral DVT, obesity, and older age. By preventing the initial DVT and DVT recurrence, primary and secondary prophylaxis of DVT will reduce occurrence of PTS. The effectiveness of elastic compression stockings (ECSs) for PTS prevention is controversial. Catheter-directed thrombolysis is not effective to prevent PTS overall but may prevent more severe forms of PTS and should be reserved for select patients with extensive thrombosis, recent symptoms onset, and low bleeding risk. For patients with established PTS, the cornerstone of management is ECS, exercise, and lifestyle modifications. Surgical or endovascular interventions may be considered in refractory cases. Because of a lack of effective therapies, new approaches to preventing and treating PTS are needed. This article uses a case-based approach to discuss risk factors for PTS after DVT, how to diagnose PTS, and available means to prevent and treat PTS, with a focus on new information in the field.

A Review of the Role of Non-Vitamin K Oral Anticoagulants in the Acute and Long-Term Treatment of Venous Thromboembolism

Venous thromboembolism (VTE), which includes both deep vein thrombosis and pulmonary embolism (PE), is a very common disorder with high risk for recurrence and is associated with significant morbidity and mortality. The non-vitamin K oral anticoagulants (NOACs), which include dabigatran, rivaroxaban, apixaban, and edoxaban, have been shown to be noninferior to conventional anticoagulant therapy for the prevention of recurrent VTE and are associated with more favorable bleeding risk. Evidence from the treatment of VTE with traditional therapy (low molecular weight heparin and vitamin K antagonists) implies that extended or indefinite treatment reduces risk of recurrence. Recently, mounting evidence suggests a role for the extended use of NOACs to reduce the risk of VTE recurrence. This review summarizes the existing evidence for the extended use of NOACs in the treatment of VTE from phase III extension studies with dabigatran, rivaroxaban, and apixaban. Additionally, it examines and discusses the major society guidelines and how these recommendations may change physician practices in the near future.

Endovascular treatment of post-thrombotic and non-thrombotic iliofemoral venous outflow obstructions with self-expanding nitinol stents

BACKGROUND

The aim of the study was to investigate venous patency and clinical outcomes for endovascular treatment of iliofemoral venous obstruction in patients with post-thrombotic syndrome (PTS) and non-thrombotic iliac vein lesion (NIVL) with dedicated self-expanding nitinol stents.

PATIENTS AND METHODS

Data were collected from the prospective Swiss Venous Stent Registry, enrolling consecutive patients with a standardized follow-up procedure since January 2008. Patency was evaluated by duplex sonography and clinical outcome by various scores including the Villalta score at baseline, three, six, and 12 months, and then annually after endovascular therapy.

RESULTS

Overall, 93 patients (64 PTS, 29 NIVL) were analysed. Mean follow-up time was 20 ± 16 (range 3-70) months. A total of 11 (12 %) patients had a stent occlusion, all of which occurred in the PTS group, and 13 (14 %) patients had a symptomatic stent stenosis. Primary patency was 79 % (95 % CI 68-87 %) at 12 months and 72 % (95 % CI 59-82 %) at 24 months. In PTS patients, primary patency at 12 months was 75 % (95 % CI 61-84 %) vs. 89 % (95 % CI 63-97 %) in NIVL patients (p = 0.10). Secondary patency at 24 months was 94 % (95 % CI 84-98 %) in PTS and 100 % in NIVL, p = 0.19). Overall, 62 (67 %) patients were free from PTS at the latest follow-up with a Villalta score < 5 points. Predictive factors for the loss of primary patency were stents placed below the inguinal ligament (OR 2.59, 95 % CI, 0.99-6.84, p = 0.05).

CONCLUSIONS

In symptomatic patients with chronic iliofemoral vein obstruction, endovascular therapy with self-expanding nitinol stents was associated with favourable patency rates and clinical improvement in the majority of patients.

Post-thrombotic syndrome in patients treated with rivaroxaban or enoxaparin/vitamin K antagonists for acute deep-vein thrombosis

Post-thrombotic syndrome (PTS) is a common complication of deepvein thrombosis (DVT). Poor quality treatment with vitamin K antagonists (VKA) is a risk factor for PTS. We hypothesised that treatment with the direct oral anticoagulant (DOAC) rivaroxaban may lower PTS incidence as compared to enoxaparin/VKA, as DOACs have a more stable pharmacologic profile than VKA. We performed a post-hoc subgroup analysis of the Einstein DVT trial (n=3449). Kaplan-Meier survival analysis was performed to compare the cumulative incidence of PTS between the rivaroxaban and enoxaparin/VKA groups. Hazard ratios (HR) and 95 % confidence intervals (CI) were calculated using Cox proportional hazards models. We included 336 patients with a mean age of 58 ± 16 years and a median follow-up after index DVT of 57 months (interquartile range 48–64). Of these, 162 (48 %) had been treated with rivaroxaban and 174 (52 %) with enoxaparin/VKA. The cumulative PTS incidence at 60 months follow-up was 29 % in the rivaroxaban group and 40 % in the enoxaparin/VKA group. After adjusting for age, gender, body mass index, previous VTE, ipsilateral recurrent DVT, extent of DVT, idiopathic DVT, duration of anticoagulant treatment, compliance to assigned study medication, elastic compression stocking use and active malignancy, the HR of PTS development for rivaroxaban was 0.76 (95 % CI: 0.51–1.13). In conclusion, treatment of acute DVT with rivaroxaban was associated with a numerically lower but statistically non-significant risk of PTS compared to enoxaparin/VKA treatment. The potential effect on reducing PTS deserves evaluation in a large randomised trial.

Supplementary Material to this article is available online at www.thrombosis-online.com.

Development and validation of a tool for patient reporting of symptoms and signs of the post-thrombotic syndrome

Post-thrombotic syndrome (PTS) is a long-term complication of deepvein thrombosis (DVT). The Villalta scale is the recommended tool for diagnosing PTS, but requires a clinician’s assessment in addition to patient self-assessment. In the present study, we validated a self-administered tool for patient reporting of leg symptoms and signs as a mean to assess PTS. We first validated a form for patient self-reported Villalta (PRV1), then developed and validated a visually assisted form (PRV2). The validity of PRV1 and PRV2 was assessed in patients diagnosed with DVT between 2004 and 2012. Median time from DVT to inclusion was 5.1 and 3.5 years for PRV1 (n=162) and PRV2 (n=94), respectively. Patients were requested to complete the PRV form before a scheduled visit. PTS diagnosed by the original Villalta scale during the visit served as the reference method. PRV1 showed only moderate agreement for diagnosing PTS compared with the original Villalta scale (kappa agreement 0.60, 95 % CI 0.48–0.72), whereas PRV2 showed very good agreement (0.82, 95 % CI 0.71–0.94). In the validation of PRV2, PTS was diagnosed in 54 (57 %) patients according to the original Villalta scale and in 60 (64 %) by PRV2. The sensitivity of PRV2 to detect PTS was 98 % and the specificity was 83 %. We conclude that the visually assisted form for PRV is a valid and sensitive tool for diagnosing PTS. Such a tool could be applied in further clinical studies of PTS, making studies less resource demanding by reducing the need for in-person clinic visits.

Supplementary Material to this article is available online at www.thrombosis-online.com.

Depiction of lower limb venous anatomy in patients undergoing interventional deep venous reconstruction-the role of balanced steady state free precession MRI

OBJECTIVES

This study evaluates the use of balanced steady-state free precession MRI (bSSFP-MRI) in the diagnostic work-up of patients undergoing interventional deep venous reconstruction (I-DVR). Intravenous digital subtraction angiography (IVDSA) was used as the gold-standard for comparison to assess disease extent and severity.

METHODS

A retrospective comparison of bSSFP-MRI to IVDSA was performed in all patients undergoing both examinations for treatment planning prior to I-DVR. The severity of disease in each venous segment was graded by two board-certified radiologists working independently, according to a predetermined classification system.

RESULTS

In total, 44 patients (225 venous segments) fulfilled the inclusion criteria. A total of 156 abnormal venous segments were diagnosed using bSSFP-MRI compared with 151 using IVDSA. The prevalence of disease was higher in the iliac and femoral segments (range, 79.6-88.6%). Overall sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and the diagnostic ratio for bSSFP-MRI were 99.3%, 91.9%, 12.3, 0.007 and 1700, respectively.

CONCLUSION

This study supports the use of non-contrast balanced SSFP-MRI in the assessment of the deep veins of the lower limb prior to I-DVR. The technique offers an accurate, fast and non-invasive alternative to IVDSA. Advances in Knowledge: Although balanced SSFP-MRI is commonly used in cardiac imaging, its use elsewhere is limited and its use in evaluating the deep veins prior to interventional reconstruction is not described. Our study demonstrates the usefulness of this technique in the work-up of patients awaiting interventional venous reconstruction compared with the current gold standard.

Compression therapy for prevention of post-thrombotic syndrome

BACKGROUND

Post-thrombotic syndrome (PTS) is a long-term complication of deep vein thrombosis (DVT) that is characterised by chronic pain, swelling, and skin changes in the affected limb. One of every three people with DVT will develop post-thrombotic complications within five years. Several non-pharmaceutical measures are used for prevention of post-thrombotic syndrome during the acute phase of DVT. These include elevation of the legs and compression therapy. Clinicians and guidelines differ in their assessment of the utility of compression therapy for treatment of DVT. This is an update of a review first published in 2003.

OBJECTIVES

To determine relative effectiveness and rate of complications when compression therapy is used in people with deep vein thrombosis (DVT) for prevention of post-thrombotic syndrome (PTS).

SEARCH METHODS

For this update, the Cochrane Vascular Information Specialist (CIS) searched the Cochrane Vascular Specialised Register (20 March 2017) and CENTRAL (2017, Issue 2). The CIS also searched trial registries for details of ongoing or unpublished studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and controlled clinical trials (CCTs) of compression therapy, such as bandaging and elastic stockings, in people with clinically confirmed DVT. The primary outcome was the occurrence of PTS.

DATA COLLECTION AND ANALYSIS

Two review authors (DK and EvL) identified and assessed titles and abstracts for relevance, and a third review author (DA) verified this assessment independently. Review authors imposed no restrictions on date or language of publications. Three review authors (DA, DK, EvL) used data extraction sheets to independently extract study data. We resolved disagreements by discussion.

MAIN RESULTS

We identified 10 RCTs with a total of 2361 participants that evaluated compression therapy. The overall methodological quality of these trials was low. We used only five studies in meta-analysis owing to differences in intervention types and lack of data. Three studies compared elastic compression stockings (pressure of 30 to 40 mmHg at the ankle) versus no intervention. Two studies compared elastic compression stockings (pressure 20 to 40 mmHg) versus placebo stockings. Overall, use of elastic compression stockings led to a clinically significant reduction in the incidence of PTS (risk ratio (RR) 0.62, 95% confidence interval (CI) 0.38 to 1.01; P = 0.05; 1393 participants; 5 studies; low-quality evidence); no reduction in the incidence of severe PTS (RR 0.78, 95% CI 0.53 to 1.15; P = 0.21; 1224 participants; 4 studies; low-quality evidence); and no clear difference in DVT recurrence (RR 0.94, 95% CI 0.69 to 1.28; 1212 participants; 4 studies; P = 0.69; low-quality evidence). We did not pool data on the incidence of pulmonary embolism because this information was poorly reported, but we observed no differences between groups included in individual studies (low-quality evidence).Two studies evaluated effects of compression in the acute phase versus no compression treatment and found no differences in the incidence of PTS (RR 0.76, 95% CI 0.49 to 1.16; P = 0.2; 101 participants). One study reported that thigh-length stockings did not provide better protection against development of PTS than knee-length stockings (RR 0.92, 95% CI 0.66 to 1.28; P = 0.6; 267 participants). Another trial reported that wearing compression stockings for two years seemed to be superior to wearing them for one year in terms of PTS incidence.Two of the 10 included studies described patient satisfaction and quality of life (moderate-quality evidence), using different measurement systems. The first study showed significant improvement in well-being and DVT-related quality of life with compression treatment (P < 0.05) compared with bed rest, and the second study showed no differences in quality of life scores between compression and placebo groups. Four studies poorly reported side effects (low-quality evidence) that included itching, erythema, and other forms of allergic reaction and described no serious adverse events. Compliance with wearing of compression stockings was generally high but varied across studies.

AUTHORS' CONCLUSIONS

Low-quality evidence suggests that elastic compression stockings may reduce the occurrence of PTS after DVT. We downgraded the quality of evidence owing to considerable heterogeneity between studies and lack of or unclear risk of blinding due to clinical assessment scores. No serious adverse effects occurred in these studies. Large randomised controlled trials are needed to confirm these findings because of current lack of high-quality evidence and considerable heterogeneity.

The importance of post thrombotic syndrome as an outcome after deep venous thrombosis: A survey of Canadian thrombosis clinicians

OBJECTIVES

The development of post thrombotic syndrome (PTS) is a major source of morbidity and reduced quality of life. We sought to determine the value assigned by clinicians to post thrombotic syndrome and whether clinicians believe that any post thrombotic syndrome or severe post thrombotic syndrome are important outcomes to assess after deep vein thrombosis (DVT) as compared to other outcomes.

DESIGN

The design of the study was a self-responded electronic survey. Questions for the online survey were designed by two authors (R.I. and E.G.).

METHODS

The survey was distributed to 233 members of Thrombosis Canada and the Canadian Society for Vascular Surgery between August 2014 and October 2014.

RESULTS

There were 84 responses to the survey with complete responses were obtained from 71 respondents for a response rate of 36%. PTS was ranked as a significantly less important outcome after DVT than recurrent DVT, pulmonary embolism during treatment, major bleeding, death, quality of life, venous ulceration and severe post thrombotic syndrome (all comparisons p<0.05 by two sample t-test).

CONCLUSIONS

Our survey determined that "any post thrombotic syndrome" is perceived by physicians as less important than other DVT outcomes. Thus, "Severe PTS" and not "Any PTS" should be included as an outcome measure in studies investigating acute DVT.

Late consequences of venous thromboembolism: Measuring quality of life after deep vein thrombosis and pulmonary embolism

The identification of specific post-thrombotic complications as well as an increased appreciation of the importance of patient-reported outcome measures have triggered an interest in studying health-related quality of life (HRQoL) in patients with a history of venous thromboembolism (VTE). In order to enable a comprehensive assessment of HRQoL in clinical trials it is recommended that both generic and disease-specific questionnaires be used. SF-36 and EQ-5D are the most widely used generic questionnaires in VTE studies, whereas several disease-specific questionnaires have been developed to evaluate HRQoL following deep vein thrombosis (DVT) and in chronic venous disease (CVD). The most widely used of these is the VEINES-QOL/Sym, which was developed for CVD. VT-QOL and DVTQOL are both questionnaires developed to evaluate HRQoL after DVT, while PEmb-QoL is currently the only available disease-specific questionnaire developed specifically for pulmonary embolism (PE). Although studies show inconsistent results, patients who sustain DVT seem in general to report similar HRQoL compared to the general population. However, patients who develop PTS after DVT report poorer HRQoL using both generic and disease-specific questionnaires. HRQoL appears to be impaired in patients who sustain PE compared to the general population. In these patients, persistent dyspnea after PE has been shown to be a predictor of reduced HRQoL. Further work is needed to develop practical, patient-derived, valid, reliable and responsive disease-specific HRQoL instruments covering the specific aspects of these diseases.

The natural history and outcomes of line-associated upper extremity deep venous thromboses in critically ill patients

OBJECTIVE

Anticoagulation remains the standard of care for line-associated upper extremity deep venous thrombosis (UEDVT). This treatment carries the risk of hemorrhagic complications, possibly more so in surgical patients. Considering the low-risk profile of UEDVT-which is associated with fewer, less severe pulmonary emboli than lower extremity deep venous thrombosis-current UEDVT treatment guidelines may be overly aggressive. The goal of this study was to review outcomes of line-associated UEDVT in critically ill patients and to define the efficacy of current treatment protocols in pulmonary embolism (PE) prevention while avoiding hemorrhagic complications.

METHODS

A retrospective review was performed of 193 consecutive patients admitted to the medical and surgical intensive care unit (ICU) at a tertiary care hospital between 2009 and 2014 diagnosed with acute line-associated UEDVT by duplex ultrasound. The examined treatment arms included anticoagulation with intent to reach therapeutic levels, prophylactic or subtherapeutic anticoagulation, and no anticoagulation. Primary outcomes included major hemorrhage (defined as any intracranial hemorrhage or any hemorrhage resulting in transfusion, ICU readmission, or death), PE, in-hospital mortality, total hospital length of stay (LOS), and ICU LOS.

RESULTS

Of the 10,907 patients, 161 (1.48%) were diagnosed with acute line-associated UEDVT, 81 of 6027 in the medical ICU (1.34%) and 80 of 4880 in the surgical ICU (1.64%), after exclusion of 32 patients with concurrent lower extremity deep venous thrombosis. In total, 122 patients (75.8%) received anticoagulation with intent to reach therapeutic levels, 23 (14.3%) received prophylactic anticoagulation, and 16 (9.94%) received no anticoagulation. Major hemorrhage was significantly more common than symptomatic PE in all patients (15.5% vs 4.97%; P < .001). A single fatal PE and two fatal hemorrhages were recorded across the series. There was no significant difference in in-hospital mortality (34.8% vs 16.7%; P = .726) or ICU LOS (33.1 vs 18.3 days; P = .739) for patients who developed major hemorrhage or symptomatic PE. On multivariate analysis, incidence of symptomatic PE was not significantly related to Acute Physiology and Chronic Health Evaluation III score (P = .963), anticoagulation regimen (P = .940), catheter type (P = .313), or bacteremia (P = .833).

CONCLUSIONS

Major hemorrhagic complications are more common than symptomatic PE after anticoagulation for line-associated UEDVT in ICU patients, raising concern that current treatment guidelines are too aggressive. These data necessitate further prospective investigation to determine the optimal treatment protocol for line-associated UEDVT in this critically ill cohort.

Novel perspectives on diagnosis and clinical significance of the post-thrombotic syndrome in children

INTRODUCTION

Given the increase in venous thromboembolic events (VTE) in children, the incidence, diagnosis and management of post thrombotic syndrome (PTS) in children is of increasing interest. Current challenges facing clinicians caring for children with VTE is the limited evidence of the long-term outcomes for this cohort; specifically the significance and potential functional impairment associated with PTS.

AREAS COVERED

This paper reviews the current evidence to elucidate the risk factors for PTS in children, methods for diagnosis and management of PTS in children (aged less than 18 years). Medline, Cinahl and PsycINFO database searches were undertaken using key search terms. Priority areas in need of further research are highlighted. Expert commentary: The two paediatric PTS assessment tools currently in use have been acknowledged to overcall the incidence of mild PTS in children. A PTS tool's ability to distinguish between clinically significant PTS and mild PTS is crucial. Variation in how PTS has been reported in children across the literature suggests that the real incidence of moderate and /or clinically significant PTS in children is unknown. Furthermore, evidence is lacking about the functional impairment experienced by children with clinically significant PTS and what this means for their long-term health.

After deep vein thrombosis, which patients refer to vascular specialist for anticoagulant withdrawal? A Delphi study results between general practitioners and vascular specialists

AIM

Deep vein thrombosis (DVT) is a potential serious common disease. Its management is, except in particular cases, on an outpatient basis. General practitioner's (GP) role usually includes the treatment risk/benefit reassessment. The treatment duration can vary and is difficult to define. The national and international guidelines do not explain clearly when to refer, or not, to a vascular specialist in order to stop treatment. The study's objective was to identify, for DVT, when a GP has to refer or not to a vascular specialist, for anticoagulant withdrawal.

METHODS

A modified Delphi consensus study had been conducted by a panel of general practitioners and vascular specialists to identify, in which situations all clinicians agree that GPs can stop anticoagulation on their own and other situations in which GP have to refer to vascular specialists. Clinical situations and their respective duration of anticoagulant therapy have been identified by a DVT management guideline literature research.

RESULTS

After two rounds, a strong agreement had been reached for each clinical situation. For 7 clinical situations, GPs were able to stop anticoagulation on their own, for 13 clinical situations; it was necessary to refer to a vascular specialist. We obtained a consensus regarding 3 modulating factors.

DISCUSSION

Consensual situations, in which the general practitioners may be able to stop anticoagulation themselves, are isolated distal DVT without cancer and proximal DVT caused by a major reversible risk factor. Situations justifying a vascular medical advice were unprovoked DVT, DVT in a context of pregnancy, postpartum, cancer and proximal DVT in a context of hormonal therapy.

Post thrombotic syndrome following deep vein thrombosis in paediatric patients

Background Although well characterised in adults, less is known about post-thrombotic syndrome in children. In this review, current knowledge regarding paediatric post-thrombotic syndrome is summarised, with particular emphasis on pathophysiology, aetiology, diagnosis and management. Methods A Medline literature review was performed using search terms 'post thrombotic syndrome', 'post phlebitic syndrome', paediatric and children. Relevant articles were identified and included for summation analysis. Results The incident of paediatric venous thromboembolism is rising. Deep vein thrombosis can cause venous hypertension through a combination of venous reflux, venous obstruction and impairment of the calf muscle pump, leading to development of post-thrombotic syndrome. In children, this is more likely to occur if deep vein thrombosis diagnosis and treatment are delayed, if a higher number of vessels are involved, and if factors such as D-dimer are elevated at diagnosis and throughout treatment. Post-thrombotic syndrome occurs in about 26% of paediatric deep vein thrombosis, though the results of individual studies vary widely. A number of tools exist to diagnose paediatric post-thrombotic syndrome, including the modified Villalta scale and Manco-Johnson instrument. Once post-thrombotic syndrome develops, the mainstay of treatment remains supportive, with little evidence of benefit from pharmacological measures. Conclusion Surgical or interventional treatment is not advised except in exceptional cirumstances, due to variable prognosis of PTS in paediatric populations with rising incidence of paediatric venous thromboembolism, it follows that the prevalence of post-thrombotic syndrome in children may also increase. Evidence-based venous thromboembolism prevention strategies need to be implemented for prevention of deep vein thrombosis, but when it does occur, deep vein thrombosis requires prompt and effective treatment to prevent post-thrombotic syndrome. Optimum treatment strategies for post-thrombotic syndrome require further investigation.

Oral anticoagulants, effect on thrombus resolution and post-thrombotic syndrome

INTRODUCTION

Venous thromboembolism is a frequently occurring phenomenon with a high risk of acute and chronic complications. To prevent these, subjects are treated with surgical options to restore venous blood flow combined with medical treatment or medical treatment alone. Despite great therapeutic advances considerable morbidity still persists. For example, thrombosis of the leg can result in post-thrombotic syndrome, which has a great impact on quality of life. The best management to prevent the post-thrombotic syndrome is a topic of research and debate. In this study, we searched the literature to identify studies that used oral anticoagulants and evaluated their properties for resolution of thrombus and hence prevention of the post-thrombotic syndrome.

METHODS

We searched PubMed, The Cochrane Library, and four international medical journals frequently reporting on venous thromboembolism. Furthermore, we looked at Clinicaltrials.gov for current research on this topic.

RESULTS

Only three suitable articles were identified.

DISCUSSION

We found experimental evidence that direct thrombin inhibitors and factor Xa inhibitors have an influence on clot lysis favoring a quicker recanalization compared to warfarin. Future studies investigating these effects in humans are warranted.

RE-COVERY DVT/PE: Rationale and design of a prospective observational study of acute venous thromboembolism with a focus on dabigatran etexilate

The therapeutic management of venous thromboembolism (VTE) is rapidly evolving. Following the positive results of pivotal large-scale randomised trials, the non-vitamin K antagonist oral anticoagulants (NOACs) represent an important alternative to standard anticoagulation. In phase III studies, dabigatran was as effective as, and significantly safer than warfarin. Additional information on real-world data of dabigatran is now warranted. RE-COVERY DVT/PE is a multi-centre, international, observational (i. e. non-interventional) study enrolling patients with acute DVT and/or PE within 30 days after objective diagnosis. The study is designed with two phases. Phase 1 has a cross-sectional design, enrolling approximately 6000 patients independently of treatment choice, with the aim of providing a contemporary picture of the management of VTE worldwide. Phase 2 has a prospective cohort design, with follow-up of one year, enrolling 8000 patients treated with dabigatran or vitamin K antagonists (VKAs) with the aim of comparing their safety, defined by the occurrence of major bleeding, and effectiveness, defined by the occurrence of symptomatic recurrent VTE. RE-COVERY DVT/PE will complement both the results of other observational studies in this field and the results of phase III studies with dabigatran, in particular by assessing its clinical benefit in various patient subgroups treated in routine clinical practice.

Pharmacomechanical thrombectomy for iliofemoral deep vein thrombosis

BACKGROUND

Deep venous thrombosis (DVT) occurs in approximately one in 1000 adults every year, and has an annual mortality of 14.6%. In particular, iliofemoral DVT can lead to recurrent thrombosis and post-thrombotic syndrome (PTS), a painful condition which can lead to chronic venous insufficiency, oedema, and ulceration. It causes significant disability, impaired quality of life, and economic burden. Early thrombus removal techniques have been advocated in patients with an iliofemoral DVT in order to improve vein patency, prevent valvular dysfunction, and reduce future complications, such as post-thrombotic syndrome and venous ulceration. One such technique is pharmacomechanical thrombectomy, a combination of catheter-based thrombectomy and catheter-directed thrombolysis.

OBJECTIVES

To assess the effects of pharmacomechanical thrombectomy versus anticoagulation (alone or with compression stockings), mechanical thrombectomy, thrombolysis, or other endovascular techniques in the management of people with acute DVT of the iliofemoral vein.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Specialised Register (last searched December 2015) and the Cochrane Register of Studies (last searched December 2015). We searched clinical trials databases for details of ongoing or unpublished studies and the reference lists of relevant articles retrieved by electronic searches for additional citations.

SELECTION CRITERIA

Randomised controlled trials in which patients with an iliofemoral deep vein thrombosis were allocated to receive pharmacomechanical thrombectomy versus anticoagulation, mechanical thrombectomy, thrombolysis (systemic or catheter directed thrombolysis), or other endovascular techniques for the treatment of iliofemoral DVT.

DATA COLLECTION AND ANALYSIS

At least two review authors independently assessed studies identified for potential inclusion.

MAIN RESULTS

We found no randomised controlled trials that met the eligibility criteria for this review. We identified one ongoing study.

AUTHORS' CONCLUSIONS

There were no randomised controlled trials that assessed the effects of pharmacomechanical thrombectomy versus anticoagulation (alone or with compression stockings), mechanical thrombectomy, thrombolysis, or other endovascular techniques in the management of people with acute DVT of the iliofemoral vein that met the eligibility criteria for this review. Further high quality randomised controlled trials are needed.

Guidance for the prevention and treatment of the post-thrombotic syndrome

The post-thrombotic syndrome (PTS) is a frequent, potentially disabling complication of deep vein thrombosis (DVT) that reduces quality of life and is costly. Clinical manifestations include symptoms and signs such as leg pain and heaviness, edema, redness, telangiectasia, new varicose veins, hyperpigmentation, skin thickening and in severe cases, leg ulcers. The best way to prevent PTS is to prevent DVT with pharmacologic or mechanical thromboprophylaxis used in high risk patients and settings. In patients whose DVT is treated with a vitamin K antagonist, subtherapeutic INRs should be avoided. We do not suggest routine use of elastic compression stockings (ECS) after DVT to prevent PTS, but in patients with acute DVT-related leg swelling that is bothersome, a trial of ECS is reasonable. We suggest that selecting patients for catheter-directed thrombolytic techniques be done on a case-by-case basis, with a focus on patients with extensive thrombosis, recent symptoms onset, and low bleeding risk, who are seen at experienced hospital centers. For patients with established PTS, we suggest prescribing 20–30 mm Hg knee-length ECS to be worn daily. If ineffective, a stronger pressure stocking can be tried. We suggest that intermittent compression devices or pneumatic compression sleeve units be tried in patients with moderate-to-severe PTS whose symptoms are inadequately controlled with ECS alone. We suggest that a supervised exercise training program for 6 months or more is reasonable for PTS patients who can tolerate it. We suggest that management of post-thrombotic ulcers should involve a multidisciplinary approach. We briefly discuss upper extremity PTS and PTS in children.

Venous thromboembolism and subsequent permanent work-related disability

Essentials The burden of venous thromboembolism (VTE) related to permanent work-related disability is unknown. In a cohort of 66 005 individuals, the risk of work-related disability after a VTE was assessed. Unprovoked VTE was associated with 52% increased risk of work-related disability. This suggests that indirect costs due to loss of work time may add to the economic burden of VTE.

SUMMARY

Background The burden of venous thromboembolism (VTE) related to permanent work-related disability has never been assessed among a general population. Therefore, we aimed to estimate the risk of work-related disability in subjects with incident VTE compared with those without VTE in a population-based cohort. Methods From the Tromsø Study and the Nord-Trøndelag Health Study (HUNT), Norway, 66 005 individuals aged 20-65 years were enrolled in 1994-1997 and followed to 31 December 2008. Incident VTE events among the study participants were identified and validated, and information on work-related disability was obtained from the Norwegian National Insurance Administration database. Cox-regression models using age as time-scale and VTE as time-varying exposure were used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs) adjusted for sex, body mass index, smoking, education level, marital status, history of cancer, diabetes, cardiovascular disease and self-rated general health. Results During follow-up, 384 subjects had a first VTE and 9862 participants were granted disability pension. The crude incidence rate of work-related disability after VTE was 37.5 (95% CI, 29.7-47.3) per 1000 person-years, vs. 13.5 (13.2-13.7) per 1000 person-years among those without VTE. Subjects with unprovoked VTE had a 52% higher risk of work-related disability than those without VTE (HR, 1.52; 95% CI, 1.09-2.14) after multivariable adjustment, and the association appeared to be driven by deep vein thrombosis. Conclusion VTE was associated with subsequent work-related disability in a cohort recruited from the general working-age population. Our findings suggest that indirect costs because of loss of work time may add to the economic burden of VTE.

Optimizing the prophylaxis of hospital-acquired deep vein thrombosis and pulmonary thromboembolism

Aim. To reduce the number of preventable hospital-acquired venous thromboembolic events (HA-VTE) and to improve the quality of VTE prophylaxis at multiprofile hospital. Materials and methods. A comprehensive approach to preventing HA-VTE was developed, which involved the global trigger tool method to assess adverse events, as well as the computerized clinical decision support system (CDSS) to prevent HA-VTE on the basis of relevant clinical practice guidelines, and HA-VTE registry. Results. A total of 50 patients (15 men, 35 women; their median age was 70.5 years) with HA-VTE were included in the HA-VTE registry in January 2014 to June 2015. Assessment of a trend in the prevalence of HA-VTE when introducing CDSS to prevent VTE showed its statistically significant decline in the total number of HA-VTE cases (χ2=7.325, df=1; p=0.0068) and in that of HA-VTE in surgical patients (χ2=7.266, df=1; p=0.0070). The statistical significance of χ2 for linear trend was not achieved for medical patients, which is probably due to the small sample size (χ2=2.764, df=1; p=0.0964). While introducing CDSS, there was a statistically significant reduction in the incidence of postoperative VTE from 8.76 to 4.17 cases per 1000 interventions (χ2=5.347, df=1; p=0.0208; the absolute values of HA-VTE and surgical interventions were used for the calculation). Conclusion. The proposed comprehensive approach can substantially increase the detection rate of HA-VTE and decrease its incidence rates. This requires a personified assessment of the risk of VTE and hemorrhage in all hospitalized patients on day 1 of their admission, timely initiation of recommended VTE prophylaxis, and dynamic assessment of the risk of VTE and hemorrhage for timely correction of the prophylaxis.

Endovascular stent placement for chronic post-thrombotic symptomatic ilio-femoral venous obstructive lesions: a single-center study of safety, efficacy and quality-of-life improvement

BACKGROUND

Post-thrombotic syndrome (PTS) is a frequent complication of deep vein thrombosis (DVT) despite adequate treatment. Venous angioplasty and stent placement has been progressively used to restore and maintain venous patency in PTS patients. This study reports our single-center experience with the use of endovascular treatment for chronic post-thrombotic symptomatic ilio-femoral venous obstructive lesions.

METHODS

A prospective mono-centric observational cohort study of PTS patients with chronic symptomatic ilio-femoral venous obstructive lesions referred for endovascular treatment was conducted from March 2012 to April 2016. Procedure consisted in recanalization, pre-dilation and self-expandable stenting of stenotic or occluded iliac and/or femoral veins. Severity of PTS, quality-of-life and treatment outcomes were assessed using Villalta scale and Chronic Venous Insufficiency Questionnaire (CIVIQ-20) at baseline and 3 months after the procedure. Imaging follow-up was based on duplex ultrasound (US) and computed tomography (CT).

RESULTS

Twenty-one patients (11 females, 10 males; median age, 41 years; range, 32-60) were included. Recanalization and stenting was successfully accomplished in all prime procedures, 4 patients benefitted from an additional procedure. Immediate technical success rate was 96% considering 25 procedures, performed without any complications. Median follow-up was 18 months (range, 6-30 months) with a 90.5% stent patency rate. Villalta score significantly decreased from baseline compared with 3 months after the procedure [14 (range, 11-22) and 5 (range, 1-10), respectively, P<0.0001], showing a significant decrease in the severity of PTS. CIVIQ-20 score significantly decreased from baseline compared with 3 months after stenting [48.5 (range, 39-73) and 26.5 (range, 21-45), respectively, P<0.0001] thus showing a significant improvement of quality-of-life. Post-procedural CIVIQ-20 score was significantly associated with Villalta score (95% CI, 1.53-2.95; P<0.0001).

CONCLUSIONS

Our results confirm the high clinical success rate and safety of endovascular PTS treatment and highlight the significant impact of stenting on the quality of life of patients with chronic symptomatic ilio-femoral venous obstructive lesions.

The post-thrombotic syndrome

Post-thrombotic syndrome (PTS) is a common complication of deep vein thrombosis (DVT) in the legs. Risk factors include recurrent ipsilateral DVT, proximal vein involvement, persistent occlusion of the deep venous system, obesity, and pre-existing chronic venous disease. Compression therapy, exercise, and weight loss, as well as effective anticoagulation of the initial DVT and secondary thromboprophylaxis, are all important aspects in the prevention and treatment of post-thrombotic syndrome.

Safety and Effectiveness of Stent Placement for Iliofemoral Venous Outflow Obstruction: Systematic Review and Meta-Analysis

BACKGROUND

Endovenous recanalization of iliofemoral stenosis or occlusion with angioplasty and stent placement has been increasingly used to maintain long-term venous patency in patients with iliofemoral venous outflow obstruction. The purpose of this systematic review and meta-analysis was to determine safety and effectiveness of venous stent placement in patients with iliofemoral venous outflow obstruction.

METHODS AND RESULTS

We searched MEDLINE and EMBASE for studies evaluating safety or effectiveness of stent placement in patients with iliofemoral venous outflow obstruction. Data were extracted by disease pathogenesis: nonthrombotic, acute thrombotic, or chronic post-thrombotic. Main outcomes included technical success, periprocedural complications, symptom relief at final follow-up, and primary/secondary patency through 5 years. A total of 37 studies reporting 45 treatment effects (nonthrombotic, 8; acute thrombotic, 19; and chronic post-thrombotic, 18) from 2869 patients (nonthrombotic, 1122; acute thrombotic, 629; and chronic post-thrombotic, 1118) were included. Technical success rates were comparable among groups, ranging from 94% to 96%. Complication rates ranged from 0.3% to 1.1% among groups for major bleeding, from 0.2% to 0.9% for pulmonary embolism, from 0.1% to 0.7% for periprocedural mortality, and from 1.0% to 6.8% for early thrombosis. Patient symptom relief data were reported inconsistently. At 1 year, primary and secondary patency were 96% and 99% for nonthrombotic, 87% and 89% for acute thrombotic, and 79% and 94% for chronic post-thrombotic.

CONCLUSIONS

Stent placement for iliofemoral venous outflow obstruction results in high technical success and acceptable complication rates regardless of cause of obstruction.

Short-Term Anticoagulant Therapy and Thrombus Location Are Independent Risk Factors for Delayed Recanalization of Deep Vein Thrombosis

Background

Prompt recanalization of the vein containing the thrombus is an important goal during the initial treatment of DVT, and risk factors for delayed recanalization in patients with deep vein thrombosis (DVT) in the lower extremities need to be determined.

Material/Methods

A total of 174 patients with DVT in lower extremities were recruited from June 2014 to March 2015 at our hospital. Duplex ultrasound scanning was conducted for all patients at 1 and 6 months after baseline evaluation. We divided the patients into recanalization and non-recanalization groups and analyzed risk factors for delayed recanalization.

Results

The univariate analysis revealed that an oral anticoagulant time of less than 3 months and venous thrombus location were risk factors for delayed recanalization (P<0.01). However, age, gender, hypertension, diabetes, pulmonary embolism, incidence factors, the use of catheter-directed thrombolytic (CDT) drugs, and inferior vena cava filter (IVCF) implantation had no influence on the incidence of delayed recanalization in patients with DVT (P>0.05). The multivariate analysis showed that patients with an anticoagulant time of less than 3 months had a lower incidence of recanalization than those with an anticoagulant time of more than 3 months (OR=2.358, P<0.05). The risk of delayed recanalization in patients with proximal DVT was 7 times higher than that in patients with distal DVT.

Conclusions

Duration of anticoagulant treatment of less than 3 months and venous thrombus location are independent risk factors for delayed recanalization of DVT in the lower extremities.

Post-thrombotic syndrome after catheter-directed thrombolysis for deep vein thrombosis (CaVenT): 5-year follow-up results of an open-label, randomised controlled trial

BACKGROUND

Post-thrombotic syndrome is a common complication after acute proximal deep vein thrombosis (DVT) and is associated with reduced quality of life and a substantial cost burden. In the 2-year results of the CaVenT study, additional catheter-directed thrombolysis reduced the risk of post-thrombotic syndrome by 14% compared with conventional therapy, but did not affect quality of life. In this study we report results at the 5-year follow-up, aiming to assess whether findings for post-thrombotic syndrome and quality of life have persisted.

METHODS

Between Jan 3, 2006, and Dec 22, 2009, we recruited patients aged 18-75 years with a first-time high proximal leg DVT from 20 hospitals in the Norwegian southeastern health region. With sealed envelopes, participants were randomly assigned (1:1) to standard treatment with compression stockings and anticoagulants (control group) or to standard treatment plus catheter-directed thrombolysis with alteplase within 21 days from symptom onset. Pre-specified outcomes in this analysis were post-thrombotic syndrome at 5 years as assessed with the Villalta score and scores for quality of life at 5 years with EQ-5D and the disease-specific VEINES-QOL/Sym. Analyses were by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00251771.

FINDINGS

At 5 year follow-up (last date Oct 14, 2014), data were available for 176 patients (84% of the 209 patients originally randomised)--87 originally assigned to catheter-directed thrombolysis and 89 originally assigned to the control group. 37 patients (43%; 95% CI 33-53) allocated to catheter-directed thrombolysis developed post-thrombotic syndrome, compared with 63 (71%; 95% CI 61-79) allocated to the control group (p<0·0001), corresponding to an absolute risk reduction of 28% (95% CI 14-42) and a number needed to treat of 4 (95% CI 2-7). Four (5%) patients assigned to catheter-directed thrombolysis and one (1%) to standard treatment had severe post-thrombotic syndrome (Villalta score ≥ 15 or presence of an ulcer). Quality-of-life scores with either assessment scale did not differ between the treatment groups.

INTERPRETATION

Additional catheter-directed thrombolysis resulted in a persistent and increased clinical benefit during follow-up for up to 5 years, supporting the use of additional catheter-directed thrombolysis in patients with extensive proximal DVT. However, allocation to this therapy did not lead to better quality of life. The optimal endovascular thrombolytic approach needs further investigation.

FUNDING

Southeastern Norway Regional Health Authority, the Research Council of Norway, University of Oslo, Oslo University Hospital.

Comparison of the Novel Oral Anticoagulants Apixaban, Dabigatran, Edoxaban, and Rivaroxaban in the Initial and Long-Term Treatment and Prevention of Venous Thromboembolism: Systematic Review and Network Meta-Analysis

Background

Anticoagulation with low molecular weight heparin and vitamin K antagonists is the current standard of care (SOC) for venous thromboembolism (VTE) treatment and prevention. Although novel oral anti-coagulants (NOACs) have been compared with SOC in this indication, no head-to-head randomised controlled trials (RCTs) have directly compared NOACs. A systematic review and network meta-analysis (NMA) were conducted to compare the efficacy and safety of NOACs for the initial and long-term treatment of VTE.

Methods

Electronic databases (accessed July 2014) were systematically searched to identify RCTs evaluating apixaban, dabigatran, edoxaban, and rivaroxaban versus SOC. Eligible patients included adults with an objectively confirmed deep vein thrombosis (DVT), pulmonary embolism (PE) or both. A fixed-effect Bayesian NMA was conducted for outcomes of interest, and results were presented as relative risks (RR) and 95% credible intervals (Crl).

Results

Six Phase III RCTs met criteria for inclusion: apixaban (one RCT; n = 5,395); rivaroxaban (two RCTs; n = 3,423/4,832); dabigatran (two RCTs; n = 2,539/2,568); edoxaban (one RCT; n = 8,240). There were no statistically significant differences between the NOACs with regard to the risk of ‘VTE and VTE-related death. Apixaban treatment was associated with the most favourable safety profile of the NOACs, showing a statistically significantly reduced risk of ‘major or clinically relevant non-major (CRNM) bleed’ compared with rivaroxaban (0.47 [0.36, 0.61]), dabigatran (0.69 [0.51, 0.94]), and edoxaban (0.54 [0.41, 0.69]). Dabigatran was also associated with a significantly lower risk of ‘major or CRNM bleed’ compared with rivaroxaban (0.68 [0.53, 0.87]) and edoxaban (0.77 [0.60, 0.99]).

Conclusions

Indirect comparisons showed statistically similar reductions in the risk of ‘VTE or VTE-related death for all NOACs. In contrast, reductions in ‘major or CRNM bleed’ for initial/long-term treatment were significantly better with apixaban compared with all other NOACs, and with dabigatran compared with rivaroxaban and edoxaban. Results from the current analysis indicate that the NOACs offer clinical benefit over conventional therapy while highlighting relative differences in their bleeding profile.

The economic burden of incident venous thromboembolism in the United States: A review of estimated attributable healthcare costs

Venous thromboembolism (VTE), which includes deep vein thrombosis and pulmonary embolism, is an important cause of preventable mortality and morbidity. In this study, we summarize estimates of per-patient and aggregate medical costs or expenditures attributable to incident VTE in the United States. Per-patient estimates of incremental costs can be calculated as the difference in costs between patients with and without an event after controlling for differences in underlying health status. We identified estimates of the incremental per-patient costs of acute VTEs and VTE-related complications, including recurrent VTE, post-thrombotic syndrome, chronic thromboembolic pulmonary hypertension, and anticoagulation-related adverse drug events. Based on the studies identified, treatment of an acute VTE on average appears to be associated with incremental direct medical costs of $12,000 to $15,000 (2014 US dollars) among first-year survivors, controlling for risk factors. Subsequent complications are conservatively estimated to increase cumulative costs to $18,000-23,000 per incident case. Annual incident VTE events conservatively cost the US healthcare system $7-10 billion each year for 375,000 to 425,000 newly diagnosed, medically treated incident VTE cases. Future studies should track long-term costs for cohorts of people with incident VTE, control for comorbid conditions that have been shown to be associated with VTE, and estimate incremental medical costs for people with VTE who do not survive. The costs associated with treating VTE can be used to assess the potential economic benefit and cost-savings from prevention efforts, although costs will vary among different patient groups.

Cost-effectiveness of edoxaban for the treatment of venous thromboembolism based on the Hokusai-VTE study

OBJECTIVE

Venous thromboembolism (VTE) is associated with almost 300,000 deaths per year in the United States. Novel oral anticoagulants (NOACs) offer an alternative to warfarin-based therapy without monitoring requirements and with fewer drug and food interactions. Edoxaban, a direct Xa inhibitor, is approved by the Food and Drug Administration (FDA), based upon results of the Hokusai-VTE Phase 3 trial. The trial demonstrated that edoxaban administered once daily after initial treatment with heparin was non-inferior in reducing the risk of VTE recurrence and caused significantly less major and clinically relevant non-major (CRNM) bleeding compared to warfarin. The objective of this study was to evaluate the cost-effectiveness of edoxaban versus warfarin for the treatment of adults with VTE.

METHODS

A cost-effectiveness model was developed using patient-level data from the Hokusai-VTE trial, clinical event costs from real-world databases, and drug acquisition costs for warfarin of $0.36 and edoxaban of $9.24 per tablet.

RESULTS

From a U.S. health-care delivery system perspective, the incremental cost-effectiveness ratio (ICER) was $22,057 per quality adjusted life year (QALY) gained. Probabilistic sensitivity analysis showed that edoxaban had an ICER <$50,000 per QALY gained relative to warfarin in 67% of model simulations. The result was robust to variation in key model parameters including the cost and disutility of warfarin monitoring.

CONCLUSION

Despite its higher drug acquisition cost, edoxaban is a cost-effective alternative to warfarin for the treatment of VTE.

Apixaban for the prophylaxis and treatment of deep vein thrombosis and pulmonary embolism: an evidence-based review

Venous thromboembolism (VTE) results in significant morbidity and mortality. The prevention and treatment of VTE is managed with anticoagulant therapy, historically parenteral anticoagulants such as unfractionated heparin, low molecular weight heparin, and fondaparinux, and oral vitamin K antagonists such as warfarin. In the last few years, several target-specific oral anticoagulants have been developed, including the direct thrombin inhibitor dabigatran and anti-Xa inhibitors rivaroxaban, apixaban, and edoxaban. The target-specific oral anticoagulants have proven to be noninferior to vitamin K antagonists and heparins in the prevention and treatment of VTE. This review will focus on the pharmacology, clinical trial data, and laboratory assessment of apixaban. Moreover, perioperative management, use in special populations, and management of bleeding complications in patients taking apixaban for the prevention and treatment of VTE will also be discussed.

Long-Term Results of Catheter-Directed Thrombolysis Combined with Iliac Vein Stenting for Iliofemoral Deep Vein Thrombosis

Purpose:

We were going to access the effect of catheter-directed thrombolytic therapy (CDT) on post-thrombotic syndrome (PTS) and the long term effects of iliac vein stenting in acute iliofemoral deep vein thrombosis (IFDVT).

Materials and Methods:

Fifty-six limbs in fifty-one patients (46 unilateral, 5 bilateral) were included from November 2001 through December 2007. Patients were classified based on the method of treatment: with stent implantation (n=37) and without stent implantation (n=19). The Villalta scale was chosen to assess for severity of PTS. The validated outcome measures were compared between the treatment groups. Statistical analysis was estimated according to the Kaplan-Meier test and Pearson chi-square test.

Results:

Mean age was 57±13 years (range, 27–76 years). Mean follow up duration was 56±12 months (range, 24–144 months). Overall 5-year primary patency rate was 66.1% (77.8% in the stenting group and 42.1% in the non-stenting group) and showed statistically significant difference between the two groups (P=0.02). The recurrence rate of deep vein thrombosis was 10/37 (27.1%) in the stenting group and 11/19 (57.9%) in the non-stenting group, respectively, which showed statistically significant difference between the two groups (P=0.024). Overall incidence of mild PTS was 8/30 (26.7%): 4/13 (30.8%) in the stenting group and 4/17 (23.5%) in the non-stenting group. None of the other factors showed statistically significant difference between the groups.

Conclusion:

Long term results of CDT in IFDVT were acceptable, and stent implantation to the iliac segment seems to have a good effect on the long term results. Therefore CDT with simultaneous stenting is recommended to improve long term results of IFDVT, if indicated.

Postthrombotic syndrome: a 2014 update

PURPOSE OF REVIEW

Postthrombotic syndrome (PTS) is the most frequent complication of deep vein thrombosis. Its pathophysiology is incompletely understood and therapeutic options are limited. This review aims to present and discuss recently published studies that have improved our knowledge related to PTS.

RECENT FINDINGS

From a prognostic point of view, some polymorphisms of plasminogen activator inhibitor-1 and platelet endothelial cell adhesion molecule 1 influence the degree of thrombus resolution after deep vein thrombosis and the subsequent rate of PTS, and could help in predicting the risk of PTS. From a therapeutic point of view, the results of a large multicenter placebo-controlled trial suggest an absence of effectiveness of elastic compression stockings to prevent PTS. In addition, although the Cavent trial of catheter-directed thrombolysis to treat ilio-femoral deep vein thrombosis showed significant reduction in the incidence of PTS that was cost-effective, secondary analyses did not show dramatic improvements in quality of life associated with use of catheter-directed thrombolysis.

SUMMARY

Choice of anticoagulant to treat deep vein thrombosis may represent a new cornerstone of PTS therapeutic management. Studies are needed to assess the impact of new oral anticoagulants and the benefit of extended courses of low molecular weight heparins on the risk of PTS.

Donning devices (foot slips and frames) enable elderly people with severe chronic venous insufficiency to put on compression stockings

OBJECTIVE/BACKGROUND

Compression therapy is highly effective in the treatment of post-thrombotic syndrome and venous leg ulcer. On average, 50-60% of the patients cooperate with compression therapy. Therefore, it is necessary to improve the user-friendliness. This prospective study investigated whether the use of donning devices can contribute to improving user-friendliness.

METHODS

Forty patients aged >65 years with severe chronic venous insufficiency (CVI; C4-C6) successively donned compression stockings in a randomized order: one 40 mmHg (CS40) or two superimposed 20 mmHg (CS20+20), each with open toe (CS-o-t) and closed toe (CS-c-t), using donning devices (three foot slips for CS-o-t; two foot slips and three frames for CS-c-t). The study endpoint was that the stocking was completely donned and correctly positioned on the patient's leg. The success rate and its association with age, sex, first time versus second time user, body mass index, abdominal circumference, ability to reach the forefoot with the hand, and hand grip strength were analyzed. Additionally, subjective evaluation by the patients was performed.

RESULTS

Without donning devices, success with CS40-c-t was 60% (24/40 patients) and with CS20+20-c-t 70% (28/40 patients) (p = .220). Using donning devices increased success rates significantly. With CS40-o-t the success rate was 88% (35/40 patients; p = .001) and with CS40-c-t it was 90% (36/40 patients; p = .002). With CS20+20-o-t and CS20+20-c-t, the success rate was 88% (35/40 patients; p = .016). The proportion of patients who successfully used either CS40 or CS20+20 increased from 73% to 93%. Relevant for the patients' success was the ability to reach the forefoot with the hand, and hand grip strength. Subjectively, donning with a device was rated significantly better than without.

CONCLUSION

Donning devices significantly improve the ability of elderly patients with CVI to don compression stockings successfully. However, there are differences in user-friendliness among the devices..

Relative importance of iliac vein obstruction in patients with post-thrombotic femoral vein occlusion

BACKGROUND

Patients with femoral vein occlusion rapidly develop collateral flow through the deep femoral vein, an embryonic collateral. In contrast, iliac vein collateralization is sparser and functionally poorer. It is not uncommon to have femoral vein occlusions associated with iliac vein obstruction, even though the femoral vein occlusion is often more readily apparent on venograms and duplex scans, whereas the iliac vein obstruction may remain occult. We examined whether percutaneous stent correction of iliac vein obstruction associated with femoral vein occlusions would yield symptomatic relief.

METHODS

During a 13-year period, 39 patients with femoral vein occlusions underwent stenting of associated iliac vein stenoses.

RESULTS

Median age was 51 years (17-86 years). The male-to-female and right-to-left ratios were 1:3 and 1:2, respectively. The clinical class of the Clinical, Etiologic, Anatomic, and Pathologic (CEAP) classification was as follows: C0-2 (with pain), two of 39 (5%); C3, 19 of 39 (48%); C4, 10 of 39 (26%); C5, one of 39 (3%); and C6, seven of 39 (18%). Concurrent ablation of a refluxive saphenous vein was performed in seven of 39 (18%). Reintervention was carried out in 14 of 39 limbs (36%). Median follow-up was 26 months (1-154 months). Median iliac vein stenosis was 80% (40%-100%). Primary, primary assisted, and secondary patency rates at 2 years were 57%, 88%, and 96%, respectively. Pain grade (visual analog scale, 0-10) improved from median 5 (0-9) to 3 (0-8) after stenting (P < .03); 12% were completely relieved of pain. Cumulative improvement in pain (≥ 3 of 10 on the visual analog scale) was 87% at 2 years. Median swelling (grade 0, none; grade 1, pitting; grade 2, ankle edema; grade 3, gross) improved from median 3/3 (0-3) to 2/3 (0-3) (P = .09, NS). Among 22 of 39 limbs (56%) with grade 3 swelling before stenting, seven of 22 limbs (32%) with grade 3 swelling improved (≥ 1 grade) after stent placement. In the 15 of 22 limbs (68%) with residual grade 3 swelling after stenting, subjective improvement was reported by all. Four of seven active ulcers (54%) healed. There were no obstructive sequelae after concurrent saphenous ablation. Saphenous flow in the erect position was not different from that of controls with patent femoral veins.

CONCLUSIONS

Percutaneous stenting of associated iliac vein obstruction in symptomatic limbs with femoral vein occlusion yields satisfactory clinical relief. The saphenous vein has little collateral role in this pathologic process and can be safely ablated if it is refluxive, in line with prior observations.

The IDEAL DVT study, individualised duration elastic compression therapy against long-term duration of therapy for the prevention of post-thrombotic syndrome: protocol of a randomised controlled trial

INTRODUCTION

Post-thrombotic syndrome (PTS) is a serious complication of deep vein thrombosis (DVT) of the leg that affects 20-50% of patients. Once a patient experiences PTS there is no treatment that effectively reduces the debilitating complaints. Two randomised controlled trials showed that elastic compression stocking (ECS) therapy after DVT for 24 months can reduce the incidence of PTS by 50%. However, it is unclear whether all patients benefit to the same extent from ECS therapy or what the optimal duration of therapy for individual patients should be. ECS therapy is costly, inconvenient, demanding and sometimes even debilitating. Tailoring therapy to individual needs could save substantial costs. The objective of the IDEAL DVT study, therefore, is to evaluate whether tailoring the duration of ECS therapy on signs and symptoms of the individual patient is a safe and effective method to prevent PTS, compared with standard ECS therapy.

METHODS AND ANALYSIS

A multicentre, single-blinded, allocation concealed, randomised, non-inferiority trial. A total of 864 consecutive patients with acute objectively documented proximal DVT of the leg are randomised to either standard duration of 24 months or tailored duration of ECS therapy following an initial therapeutic period of 6 months. Signs and symptoms of PTS are recorded at regular clinic visits. Furthermore, quality of life, costs, patient preferences and compliance are measured. The primary outcome is the proportion of patients with PTS at 24 months.

ETHICS AND DISSEMINATION

Based on current knowledge the standard application of ECS therapy is questioned. The IDEAL DVT study will address the central questions that remain unanswered: Which individual patients benefit from ECS therapy and what is the optimal individual treatment duration? Primary ethics approval was received from the Maastricht University Medical Centre.

RESULTS

Results of the study will be disseminated via peer-reviewed publications and presentations at scientific conferences.

TRIAL REGISTRATION NUMBER

NCT01429714 and NTR 2597.