Cost Effectiveness of Early Endovenous Thrombus Removal for Acute Iliofemoral Deep Vein Thrombosis in the United Kingdom

OBJECTIVE

Early clot removal using endovascular intervention aims to reduce post-thrombotic syndrome (PTS) following iliofemoral deep venous thrombosis (DVT). This may reduce long term morbidity but incurs a higher initial cost. This study examined the cost effectiveness of catheter directed thrombolysis (CDT) and pharmacochemical thrombectomy (PMT) compared with oral anticoagulation (OAC) alone for treatment of acute iliofemoral DVT in the United Kingdom.

METHODS

A combined decision tree (acute DVT complications) and Markov model (long term complications [PTS]) was used for decision analytic modelling with five states: no PTS, mild PTS, moderate PTS, severe PTS, and dead. All patients started with acute DVT. Patients who survived acute complications transitioned into the Markov model. Cycle time was six months. A healthcare payer perspective and lifetime horizon was used, adjusting for excess mortality due to history of thrombosis. Data for probabilities, transition probabilities, mortality, and utilities were obtained from the published literature. Cost data were obtained from UK NHS tariffs and published literature. Outcomes were mean lifetime cost, quality adjusted life years (QALYs), and cost effectiveness.

RESULTS

Over a patient's lifetime, OAC was more costly (£37 206) than CDT (£32 043) and PMT (£36 288). Mean lifetime QALYs for OAC (12.9) were lower than CDT (13.5) and PMT (13.3). Therefore, in the incremental cost effectiveness analysis, both CDT and PMT were dominant: CDT was less costly (-£5 163) and more effective (+0.6 QALYs) than OAC, and PMT was also less costly (-£917) and more effective (+0.3 QALYs) than OAC. Results were robust to univariable sensitivity analyses, but probabilistic sensitivity analyses suggested considerable parameter uncertainty.

CONCLUSION

Early interventional treatment of iliofemoral DVT is cost effective in the UK. Future clinical and epidemiological studies are needed to characterise parameter uncertainty. Further analysis of modern practice, alternative treatments, and optimised care models is warranted.

Effect of exercise after a deep venous thrombosis: A systematic review

Post-thrombotic syndrome (PTS) is a common complication after deep vein thrombosis (DVT) and has a major impact on physical symptoms, quality of life (QoL) and economic costs. Relatively simple lifestyle interventions as physical exercise might reduce PTS severity and increase QoL. To evaluate the direct and long-term effects of physical activity in patients with an acute or previous DVT. We conducted a systematic review through an additional search from 2007 up to March 2022, to complement the comprehensive systematic review of Kahn et al. Articles evaluating the effect of exercise after a DVT including symptoms, QoL and the incidence and severity of PTS, were included. Quality of the studies was assessed using a GRADE-like checklist and results were reported according to the PRISMA Statement. Ten studies were included, seven randomized controlled trials and three cohort studies. We identified three types of physical activity based on timing and duration; (1) early mobilisation in the acute phase of the DVT; (2) short duration exercise 1 year after DVT and (3) prolonged exercise during follow-up after a previous DVT. Early mobilisation showed improvement in QoL and pain reduction and after 2 years it resulted in a significant reduction of PTS severity. Prolonged supervised exercise resulted in improvement of QoL. In addition, positive effects on symptoms of venous insufficiency and muscle functions were observed. None of the included studies reported an increased risk of PTS or worsening of symptoms due to physical activity. Physical exercise after a DVT is safe, improves QoL, reduces pain and decreases PTS severity. Lifestyle intervention such as guided individualized training programs can be a useful supplementary therapy for patients after a DVT or for PTS patients. Optimal training programs may be identified by further studies that improve patient-oriented outcomes for both adults and children after a DVT.

TILE pilot trial study protocol: Tinzaparin Lead-in to Prevent the Post-Thrombotic syndrome study protocol

INTRODUCTION

The post-thrombotic syndrome (PTS) is a form of chronic venous insufficiency due to a prior ipsilateral deep venous thrombosis (DVT). This is a frequent complication that develops in 20%-50% of patients after a proximal DVT and is associated with significant healthcare, economic and societal consequences. In the absence of effective and well-tolerated treatment options for established PTS, effective preventative measures are needed. Anticoagulation itself reduces the risk of PTS, and low-molecular-weight heparin may reduce this further through anti-inflammatory properties targeting the initial acute inflammatory phase of DVT.

METHODS AND ANALYSIS

The Tinzaparin Lead-In to Prevent the Post-Thrombotic syndrome pilot trial is an investigator-initiated, multicentre, open-label assessor-blinded trial that will randomise patients with first acute symptomatic common femoral or iliac DVT to receive either a 3-week lead-in course of tinzaparin, followed by rivaroxaban (experimental arm) or rivaroxaban alone (control arm). Its primary objectives are to assess: (1) proportion of PTS at 6 months using the Villalta scale and (2) study feasibility, which consists of (a) the proportion of screened patients eligible for the study, (2) the proportion of eligible patients recruited and (c) the proportion of recruited patients adherent to treatment (defined as at least 80% of drug taken). This study will determine the feasibility of a subsequent larger definitive trial. Secondary outcomes include change of quality of life scores, PTS severity, global improvement, patient satisfaction, bleeding, recurrent venous thromboembolism, leg pain, death and lost to follow-up. Target recruitment will be a total of 60 participants, recruited at 5-6 centres.

ETHICS AND DISSEMINATION

Primary ethics approval was received from the Sunnybrook Health Sciences Center Research Ethics Board (approval ID 3315). Results of the study will be disseminated via peer-reviewed presentation at scientific conferences and open access publication.

TRIAL REGISTRATION NUMBER

NCT04794569.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Overall Hemostatic Potential Assay Detects Risk of Progression to Post-Thrombotic Syndrome in Anticoagulated Patients following Deep Vein Thrombosis

Deep vein thrombosis (DVT) frequently leads to post-thrombotic syndrome (PTS) which is challenging to predict and prevent. Identifying those at high risk of developing PTS may help to focus preventative strategies. Adults were recruited within 3 months of DVT diagnosis. Blood was sampled during the therapeutic anticoagulation phase. Overall hemostatic potential (OHP) assay, a spectrophotometric assay, was performed on platelet-poor plasma (PPP). In this assay, fibrin formation is triggered by small amounts of thrombin and termed the overall coagulation potential (OCP). Simultaneously, thrombin and tissue plasminogen activator are added to PPP and the resulting fibrin aggregation curve is the overall hemostatic potential (OHP). Fibrinolysis is expressed by the parameter overall fibrinolytic potential (OFP%). Patients were followed up at regular intervals. PTS was diagnosed if the Villalta score was ≥5 at least 3 months after the DVT diagnosis. Results were obtained from 190 patients (53.7% male, mean age 56.9 years). PTS developed in 62 (32.6%) patients. Patients with PTS displayed significantly higher median OCP (45.8 vs. 38.8 units, p = 0.010), OHP (12.8 vs. 9.2 units, p = 0.005) and significantly lower OFP (74.1 vs. 75.6%, p = 0.050). PTS patients had higher neutrophil/lymphocyte ratios (NLR) (2.3 vs. 1.9, p = 0.007). After multivariate analysis, proximal DVT location, history of varicose veins, NLR ≥ 2.6, OHP > 13.0 units and weight >108 kg were independent predictors for PTS. The c-statistic of the multivariate model was 0.77. This pilot study suggests that OHP testing while patients are still anticoagulated may assist in the prediction of PTS development and could assist in prognostication and targeting of preventative measures. However, larger prospective studies are needed to confirm these findings.

New and known predictors of the postthrombotic syndrome: A subanalysis of the ATTRACT trial

Introduction

Postthrombotic syndrome (PTS) remains associated with significant clinical and economic burden. This study aimed to investigate known and novel predictors of the development of PTS in participants of the ATTRACT (Acute Venous Thrombosis: Thrombus Removal With Adjunctive Catheter‐Directed Thrombolysis) trial.

Methods

We used multivariable logistic regression to identify baseline and postbaseline factors that were predictive of the development of PTS during study follow‐up, as defined by a Villalta score of 5 or greater or the development of a venous ulcer from 6 to 24 months after enrollment.

Results

Among 691 patients in the study cohort (all had proximal deep vein thrombosis [DVT] that extended above the popliteal vein, of which 57% had iliofemoral DVT), 47% developed PTS. Further, we identified that Villalta score at baseline (odds ratio [OR], 1.09 [95% confidence interval [CI], 1.05–1.13] per one‐unit increase) and employment status (unemployed due to disability: OR, 3.31 [95% CI, 1.72–6.35] vs. employed more than 35 hours per week) were predictive of PTS. In terms of postbaseline predictors, leg pain severity at day 10 (OR, 1.28 [95% CI, 1.13–1.45] per 1‐point increase in a 7‐point scale) predicted PTS. Also, patients receiving rivaroxaban on day 10 following randomization had lower rates of PTS (OR, 0.53 [95% CI, 0.33–0.86]) than patients on warfarin.

Conclusions

Novel predictors for PTS identified in our study include baseline Villalta score, leg pain severity at 10 days, and unemployed due to disability. Our findings also suggest that the initial choice of anticoagulant to treat DVT may have an impact on the development of PTS.

Patient-Completed Caprini Risk Score for Venous Thromboembolism Risk Assessment: Developed and Validated from 1,017 Medical and Surgical Patients

Background The Caprini Risk Score (CRS) is one of the most widely used risk assessment models for venous thromboembolism (VTE). A well-validated patient-completed CRS form may allow patients to self-report and simplify the evaluation by health care workers.

Methods The Chinese version of the CRS was optimized for easy understanding in a pilot study. The amended CRS form was completed by prospectively recruited patients and blinded nurses. The agreement levels of the individual questions and the total scores of patient and nurse-completed forms were compared using the Kappa value. The total scores were used for risk stratification of patients. Correlation and differences between patient and nurse-completed forms were analyzed using the Spearman correlation and Bland–Altman method, respectively.

Results We recruited 504 medical patients and 513 surgical patients, aged 52.7 ± 16.3 years, of which 443 (43.6%) were men, and 91.6% of the patients were educated beyond junior high school. The patients spent less time to complete the form compared with trained nurses. There was good question-to-question agreement between patient and nurse-completed CRS (k >0.6 for most questions, p < 0.0001). The total scores also showed good agreement (k = 0.6097, p < 0.0001), and enabled the classification of patients into different risk groups. The patient and nurse-derived scores were highly correlated (Spearman's r = 0.84), and without extreme values (p < 0.0001).

Conclusion We have created and verified a Chinese version of the patient-completed CRS, which showed good agreement and correlation with nurse-completed CRS. CRS represents a suitable tool for VTE risk assessment of hospitalized patients in China.

Performance of Open and Closed Cell Laser Cut Nitinol Stents for the Treatment of Chronic Iliofemoral Venous Outflow Obstruction in Patients Treated at a Single Centre

OBJECTIVE

A number of dedicated self expanding nitinol stents have been developed for use in the venous system, with both open cell (OC) and closed cell (CC) designs available. Data comparing these different designs are lacking. The objective of this study was to evaluate outcomes in patients treated with open and closed cells for unilateral chronic iliac vein obstruction.

METHODS

A single centre retrospective cohort study was conducted, including all patients treated with a dedicated nitinol venous stent between 2014 and 2019. Stent patency and details of re-interventions (including lysis, venoplasty, reinforcement, extension, arteriovenous fistula formation) were examined in the first post-operative year. Subgroup analysis described outcomes for patients treated with OC and CC stents ending above the inguinal ligament and those who required extension into the common femoral vein. Cox regression analysis was used to identify factors associated with loss of primary patency.

RESULTS

A total of 207 patients were included (OC 100 patients, CC 107 patients). There was no significant difference between the groups for age (OC 42 years, CC 44 years); gender (OC and CC 67% female); presence of post-thrombotic lesions (OC 71%, CC 73%); stenting across the inguinal ligament (OC 58%, CC 56%), or presence of inflow disease (OC 49%, CC 47%). Primary and cumulative patency at 12 months were similar between groups (primary: OC 63%, CC 65%; cumulative: OC 93%, CC 90%). Patients with a CC stent across the inguinal ligament had a greater risk of needing multiple re-interventions at one year compared with those with an OC stent (odds ratio 2.84, 95% confidence interval [CI] 1.16 - 6.9) but overall, the only factor significantly associated with loss of primary patency was inflow vessel disease (hazard ratio 3.39, 95% CI 1.73 - 6.62, p < .001).

CONCLUSION

OC and CC dedicated nitinol venous stents were observed to perform similarly in terms of patency and symptom improvement at one year. Disease of the inflow vessels was the most important factor associated with a loss of stent patency irrespective of stent design.

Determinants of Quality of Life in Patients with Post-Thrombotic Syndrome

OBJECTIVES

Chronic post-thrombotic syndrome (PTS) may develop in up to 50% of patients after deep vein thrombosis (DVT) and may reduce patients' quality of life (QoL). We aimed to evaluate the association of PTS severity with QoL in patients with proximal DVT submitted to medical treatment and also to identify modifiable and non-modifiable risk factors related to PTS.

METHODS

Patients with iliac or femoropopliteal DVT observed in Vascular Surgery consultation in our institution from 1 year period with unilateral DVT were selected. Patients with total vein recanalization were excluded. Villalta scale was applied to assess PTS degree and VEINES-QoL/Sym questionnaire was used as a disease-specific QoL measure. Correlation between PTS degree and VEINES-QoL/Sym score and predictors of PTS were determined.

RESULTS

56 patients accepted to enter the study. From those, 66.1% were female, 64.3% (n=36) had iliac and 35.7% (n=20) femoropopliteal DVT. PTS was present in 52.8% of iliac and 65.0% of femoropopliteal DVT patients observed in consultation (P=0.413). There was a significant correlation with PTS degree and both VEINES-QoL and VEINES-Sym scores (P<0.001). Major depression (OR=5.63, P=0.045) and regular wear of compressing stockings (OR=4.69, P=0.041) were the only independent factors associated with PTS. Patients with depression had lower QoL scores, while patients with PTS who wear compression stockings had similar QoL scores compared to patients without PTS. Ultrasound alterations (OR=3.28, P=0.174), age, gender, iliac DVT, multiple DVT and time after DVT (P>0.2) were not associated with PTS syndrome.

CONCLUSIONS

VEINES-QoL/Sym had moderate inverse correlation with PTS degree. Depression was associated with both PTS and lower QoL scores. Patients with PTS criteria compliant to wearing compressing stockings had similar QoL scores to patients without PTS.

Prevention of the post thrombotic syndrome with anticoagulation: a narrative review

The post thrombotic syndrome (PTS) is chronic venous insufficiency secondary to a prior deep vein thrombosis (DVT). It is the most common complication of VTE and, while not fatal, it can lead to chronic, unremitting symptoms as well as societal and economic consequences. The cornerstone of PTS treatment lies in its prevention after DVT. Specific PTS preventative measures include the use of elastic compression stockings (ECS) and pharmacomechanical catheter directed thrombolysis (PCDT). However, the efficacy of these treatments has been questioned by large RCTs. So far, anticoagulation, primarily prescribed to prevent DVT extension and recurrence, appears to be the only unquestionably effective treatment for the prevention of PTS. In this literature review we present pathophysiological, biological, radiological and clinical data supporting the efficacy of anticoagulants to prevent PTS and the possible differential efficacy among available classes of anticoagulants (vitamin K antagonists (VKA), low molecular weight heparins (LMWHs) and direct oral anticoagulants (DOACs)). Data suggest that LMWHs and DOACs are superior to VKAs, but no head-to-head comparison is available between DOACs and LMWHs. Owing to their potentially greater anti-inflammatory properties, LMWHs could be superior to DOACs. This finding may be of interest particularly in patients with extensive DVT at high risk of moderate to severe PTS, but needs to be confirmed by a dedicated RCT.

A Systematic Review and Meta-Analysis of 12-Month Patency After Intervention for Iliofemoral Obstruction Using Dedicated or Non-Dedicated Venous Stents

BACKGROUND

Endovascular stenting of the deep venous system has been proposed as a method to treat patients with symptomatic iliofemoral outflow obstruction. The purpose of this systematic review and meta-analysis was to compare the effectiveness of this treatment at 1-year following the development of dedicated venous stents.

METHOD AND RESULTS

We searched MEDLINE and EMBASE for studies evaluating the effectiveness of venous stent placement. Data were extracted by disease pathogenesis: non-thrombotic iliac vein lesions (NIVL), acute thrombotic (DVT), or post-thrombotic syndrome (PTS). Main outcomes included technical success, stent patency at 1 year and symptom relief. A total of 49 studies reporting outcomes in 5154 patients (NIVL, 1431; DVT, 950; PTS, 2773) were included in the meta-analysis. Technical success rates were comparable among groups (97%-100%). There were no periprocedural deaths. Minor bleeding was reported in up to 5% of patients and major bleeding in 0.5% upon intervention. Transient back pain was noted in 55% of PTS patients following intervention. There was significant heterogeneity between studies reporting outcomes in PTS patients. Primary and cumulative patency at 1 year was: NIVL-96% and 100%; DVT-91% and 97%; PTS (stents above the ligament)-77% and 94%, and; PTS (stents across the ligament)-78% and 94%. There were insufficient data to compare patency outcomes of dedicated and nondedicated venous stents in patients with acute DVT. In NIVL and PTS patients, stent patency was comparable at 1 year. There was inconsistency in the use of validated tools for the measurement of symptoms before and after intervention. When reported, venous claudication, improved in 83% of PTS patients and 90% of NIVL patients, and ulcer healing occurred in 80% of PTS patients and 32% of NIVL patients.

CONCLUSIONS

The first generation of dedicated venous stents perform comparably in terms of patency and clinical outcomes to non-dedicated technologies at 1 year for the treatment of patients with NIVL and PTS. However, significant heterogeneity exists between studies and standardized criteria are urgently needed to report outcomes in patients undergoing deep venous stenting.

Risk of a permanent work-related disability pension after incident venous thromboembolism in Denmark: A population-based cohort study

BACKGROUND

Long-term complications of venous thromboembolism (VTE) hamper physical function and impair quality of life; still, it remains unclear whether VTE is associated with risk of permanent work-related disability. We aimed to assess the association between VTE and the risk of receiving a permanent work-related disability pension and to assess whether this association was explained by comorbidities such as cancer and arterial cardiovascular disease.

METHODS AND FINDINGS

A Danish nationwide population-based cohort study consisting of 43,769 individuals aged 25 to 66 years with incident VTE during 1995 to 2016 and 218,845 birth year-, sex-, and calendar year-matched individuals from the general population, among whom 45.9% (N = 120,540) were women, was established using Danish national registries. The cohorts were followed throughout 2016, with permanent work-related disability pension as the outcome. Hazard ratios (HRs) with 95% confidence intervals (CIs) for disability pension were computed and stratified by sex and age groups (25 to 34, 35 to 44, 45 to 54, and 55 to 66 years of age) and adjusted for comorbidities and socioeconomic variables. Permanent work-related disability pensions were granted to 4,415 individuals with VTE and 9,237 comparison cohort members (incidence rates = 17.8 and 6.2 per 1,000 person-years, respectively). VTE was associated with a 3-fold (HR 3.0, 95% CI: 2.8 to 3.1) higher risk of receiving a disability pension. Adjustments for socioeconomic status and comorbidities such as cancer and cardiovascular diseases reduced the estimate (HR 2.3, 95% CI: 2.2 to 2.4). The risk of disability pension receipt was slightly higher in men than in women (HR 2.5, 95% CI: 2.3 to 2.6 versus HR 2.1, 95% CI: 2.0 to 2.3). As this study is based on medical and administrative registers, information on post-VTE care, individual health behavior, and workplace factors linked to disability pension in the general population are lacking. Furthermore, as disability pension schemes vary, our results might not be directly generalizable to other countries or time periods.

CONCLUSIONS

In this study, incident VTE was associated with increased risk of subsequent permanent work-related disability, and this association was still observed after accounting for comorbidities such as cancer and cardiovascular diseases. Our results emphasize the social consequences of VTE and may help occupational and healthcare professionals to identify vulnerable individuals at risk of permanent exclusion from the labor market after a VTE event.

Validation of Outcome Instruments for Pediatric Postthrombotic Syndrome: Introducing the Peds-VEINES-QOL, a New Health-Related Quality of Life Instrument

BACKGROUND

 There is need for validated outcome measures for postthrombotic syndrome (PTS) following pediatric venous thromboembolism (VTE), with a focus on quality of life (QoL).

AIMS

 This article assesses reliability and validity of two PTS and two QoL scales for children following lower extremity VTE.

METHODS

 Pediatric patients following lower extremity VTE were recruited from three thrombosis clinics. The Manco-Johnson (MJ) and the modified Villalta (MV) PTS scales were compared with each other and with the generic pediatric health-related QoL, PedsQL, and a newly developed pediatric venous-specific QoL, the Peds-VEINES-QOL.

RESULTS

 Eighty children following VTE and 60 healthy control children were enrolled. Internal consistency measured by Cronbach's α was high for the two QoL scales, and moderate for the two PTS scales. Inter-rater reliability using intraclass correlation coefficients was moderate to high for the MJ, MV, and Peds-VEINES-QOL, and moderate for the PedsQL. Evidence of high internal consistency by Cronbach's α coefficients, and moderate to high interitem correlations support the premise that a single construct was measured by each instrument. Correlations between the four instruments indicate convergent validity.

CONCLUSION

 The MJ and MV scales detect similar outcomes in children following VTE. As used, the MJ is slightly more sensitive to QoL because a positive diagnosis requires pain which is the leading factor in reduced QoL following deep vein thrombosis. When using the MV, a requirement for pain or abnormal use to diagnose PTS would make the MV a better predictor of QoL.

Performance of two clinical scales to assess quality of life in patients with post-thrombotic syndrome

OBJECTIVE

We directly compared the Villalta scale and the Venous Clinical Severity Score (VCSS) to determine which of the two measures would be better at capturing clinically important cases of post-thrombotic syndrome (PTS) and PTS severity compared with patient-reported quality of life (QOL) scores.

METHODS

We performed a secondary analysis of the ATTRACT (acute venous thrombosis: thrombus removal with adjunctive catheter-directed thrombolysis) trial study population. We calculated the correlations of the Villalta scores and VCSSs with QOL scores (short-form 36-item health survey [SF-36] physical component summary [PCS] and mental component summary [MCS]; and VEINES [venous insufficiency epidemiological and economic study]-QOL/symptom [VEINES-QOL/Sym] questionnaire) at each study visit (6, 12, 18, and 24 months of follow-up). The correlation of the random intercept (mean scores) and random slope (rate of change of the scores) among the Villalta scores, VCSS, and VEINES-QOL/Sym scores was assessed using a multivariate longitudinal model.

RESULTS

The median correlation between Villalta scores and VCSSs was 0.72. The median correlation between the Villalta scores and VEINES-QOL and VEINES-Sym scores at all follow-up visits was -0.68 and -0.71, respectively. The median correlation between the Villalta scores and SF-36 PCS and MCS scores was -0.51 and -0.31, respectively. For the VCSSs, the median correlation with the VEINES-QOL and VEINES-Sym scores at all follow-up visits was -0.39 and -0.41, respectively. The median correlation between the VCSSs and SF-36 PCS and MCS scores was -0.32 and -0.13, respectively. The correlations between the random effects in the multivariate longitudinal models showed a similar pattern. The effect of covariate adjustment by age, sex, and body mass index was minor.

CONCLUSIONS

The Villalta scores and VCSSs correlated strongly. The Villalta scale showed a substantially greater correlation with venous disease-specific and general QOL scores compared with the correlation with the VCSS. Our findings suggest that when a single scale is used to assess for clinically meaningful PTS, the Villalta scale will better capture the effects of PTS on patient-reported QOL.

Quality of life outcomes for patients undergoing venous stenting for chronic deep venous disease

OBJECTIVE

The objective of the study was to evaluate change in venous disease-specific quality of life (QoL) after iliac vein stenting for chronic venous outflow obstruction.

METHODS

We performed a retrospective analysis of all Venous Insufficiency Epidemiological and Economic Study - Quality of Life/Symptoms (VEINES-QoL/Sym) questionnaires completed at a single-center between 2016 and 2019 by patients treated with iliac vein stenting for chronic venous outflow obstruction. Patients were asked to complete the questionnaire at baseline (before stenting) and at subsequent follow-up appointments (after stenting), at 6, 12, 24, and 36 months. The Villalta score was recorded by a venous nurse specialist. The initial unpaired analysis compared all completed VEINES-QoL/Sym and Villalta scores at baseline to all follow-up time-points, and then compared them individually between baseline and each follow-up point. A secondary paired analysis included data only from patients who had completed the questionnaire at baseline and at least one follow-up.

RESULTS

A total of 385 questionnaires from 187 patients who completed the VEINES-QoL/Sym between 2016 and 2019 were included. The median follow-up was 12 months, 127 patients (68%) were female, and 148 (79%) were treated for post-thrombotic syndrome. The median VEINES-QoL score at baseline was 35.69 (interquartile range [IQR], 20.85-46.67). Significant improvement was observed postoperatively and sustained throughout the study period (6 months, 64.81 [IQR, 38.12-83.88]; 12 months, 60.52 [IQR, 33.6-82.3]; 24 months, 60.37 [IQR, 34.31-80.65]; 36 months, 55.98 [IQR, 39.18-81.47]). The VEINES-Sym scores demonstrated similar improvement. A secondary analysis of paired baseline/follow-up data from 61 patients confirmed significant improvement from baseline for VEINES-QoL (6 months +26.45; 12 months, +25.81; 24 months, +30.09; P ≤ .0001), VEINES-Sym (6 months, +23.86; 12 months, +20.43; 24 months, +27.55; P > .001), and Villalta scores (6 months, -3.7; 12 months, -4.2; 24 months, -6.4; P < .0001). The median Villalta score was 14 (IQR, 10-16). This score improved to 9 (IQR, 5-13) at 6 months of follow-up; to 8 (IQR, 5-11) at 12 months; to 7 (IQR, 4-12) at 24 months; and to 6 (IQR, 3.75-10.25) at 36 months (P ≤ .0001). Good correlation between the Villalta and both VEINES-QoL and SYM scores was observed at follow-up (r = 0.69 and r = 0.71, respectively; P < .0001).

CONCLUSIONS

Venous disease-specific QoL improves and severity of post-thrombotic syndrome is decreased after iliac vein stenting for chronic venous outflow obstruction. These improvements are sustained at 36-month follow-up.

[Additional possibilities in conservative treatment of patients with post-thrombotic disease of lower limbs]

AIM

This study was undertaken to evaluate efficacy of Actovegin in the composition of comprehensive therapy in patients presenting with post-thrombotic disease of lower extremities free from trophic disorders.

PATIENTS AND METHODS

The study included a total of 60 patients (28 men and 32 women) diagnosed as having post-thrombotic disease of lower limbs without trophic disorders (C1-C3 according to the CEAP classification), induced by previously endured iliofemoral phlebothrombosis. The duration of the disease varied from 1 year to 10 years. All patients for 10 days received Actovegin intravenously in drips at a dose of 1200 mg (30 ml of the drug reconstituted in 400 ml of normal saline) followed by continuing taking the drug orally in a daily dose of 1200 mg for 30 days. During the whole follow up period the patients wore class 2 compression stockings (RAL standard). The results of the carried out treatment in relation to the subjective complaints (pain, feeling of heaviness, convulsions, pruritus and paresthesias) were assessed by the visual analogue scale and based on the CIVIQ-20 questionnaire, with additionally measuring the malleolar circumference.

RESULTS

On the background of the carried out therapy the patients demonstrated a significant decrease in the oedematous syndrome in the area of the ankles. This parameter decreased form 26.88±0.39 cm to 25.02±0.35 cm (p<0.05). The patients' complaints of tingling decreased form 5.73±0.79 to 2.32±0.68 points (p<0.05), the incidence and intensity of convulsions fell from 6.51±1.39 to 3.2±0.98 points (p<0.05). The intensity of the oedematous syndrome (swelling) decreased significantly from 8.11±1.75 to 4.33±1.20 points (p<0.05), the pain syndrome fell from 7.92±1.88 to 3.12±1.45 points (p<0.05), the feeling of heaviness in the lower limbs decreased from 8.52±1.73 to 3.91±1.48 points (p<0.05). Also, improvement of the general quality of life of patients was observed (the integral parameter decreased from 63.27±1.8 to 44.33±1.19 points, p<0.05).

Measuring functional limitations after venous thromboembolism: Optimization of the Post-VTE Functional Status (PVFS) Scale

INTRODUCTION

We recently proposed a scale for assessment of patient-relevant functional limitations following an episode of venous thromboembolism (VTE). Further development of this post-VTE functional status (PVFS) scale is still needed.

METHODS

Guided by the input of VTE experts and patients, we refined the PVFS scale and its accompanying manual, and attempted to acquire broad consensus on its use.

RESULTS

A Delphi analysis was performed involving 53 international VTE experts with diverse scientific and clinical backgrounds. In this process, the number of scale grades of the originally proposed PVFS scale was reduced and descriptions of the grades were improved. After these changes, a consensus was reached on the number/definitions of the grades, and method/timing of the scale assessment. The relevance and potential impact of the scale was confirmed in three focus groups totaling 18 VTE patients, who suggested additional changes to the manual, but not to the scale itself. Using the improved manual, the κ-statistics between PVFS scale self-reporting and its assessment via the structured interview was 0.75 (95%CI 0.58-1.0), and 1.0 (95%CI 0.83-1.0) between independent raters of the recorded interview of 16 focus groups members.

CONCLUSION

We improved the PVFS scale and demonstrated broad consensus on its relevance, optimal grades, and methods of assessing among international VTE experts and patients. The interobserver agreement of scale grade assignment was shown to be good-to-excellent. The PVFS scale may become an important outcome measure of functional impairment for quality of patient care and in future VTE trials.

Prevalence and Mortality of Venous Leg Diseases of the Deep Veins: An Observational Cohort Study Based on German Health Claims Data

This study estimates the prevalence and mortality of diseases of the deep veins of the legs such as deep vein thrombosis (DVT), postthrombotic syndrome (PTS), and venous leg ulceration (VLU). We used a random sample of 250 000 patients at age 50+ years of the register of the Allgemeine Ortskrankenkasse from 2004 to 2015. Selected manifestations of venous diseases assumed as risk factors for mortality were analyzed using Cox models while adjusting for various basic demographic and health characteristics. The prevalence in 2004 was 0.05% for DVT of the femoral veins, 0.50% for DVT of any deep veins, 0.86% for PTS, and 0.91% for VLU. The mortality rate in 2004 to 2015 was 20.40 deaths/100 person-years for DVT of the femoral veins, 10.69 for DVT of any deep veins, 4.34 for PTS, and 7.02 for VLU. The model revealed a 35% higher risk (p < .001) in patients with any DVT, an 88% higher mortality (p < .001) for femoral DVT, a 23% higher risk (p < .001) for VLU, and no health disadvantage in persons with PTS. Our study revealed an increased mortality for patients with VLU and DVT. Even after adjustment for embolic events and infections of the venous ulcers mortality remained significantly higher.

Cost-Effectiveness of Betrixaban Compared with Enoxaparin for Venous Thromboembolism Prophylaxis in Nonsurgical Patients with Acute Medical Illness in the United States

BACKGROUND

Studies show that the risk of venous thromboembolism (VTE) continues post-discharge in nonsurgical patients with acute medical illness. Betrixaban is the first anticoagulant approved in the United States (US) for VTE prophylaxis extending beyond hospitalization.

OBJECTIVE

The aim was to establish whether betrixaban for VTE prophylaxis in nonsurgical patients with acute medical illness at risk of VTE in the US is cost-effective compared with enoxaparin.

METHODS

A cost-effectiveness analysis was conducted, estimating the cost per quality-adjusted life-year (QALY) gained with betrixaban (35-42 days) compared with enoxaparin (6-14 days) from a US payer perspective over a lifetime horizon. A decision tree (DT) estimated primary VTE events, thrombotic events, and treatment complications in the first 3 months based on data from the phase III Acute Medically Ill VTE Prevention with Extended Duration Betrixaban study. A Markov model estimated recurrent events and long-term complication risks from published literature. EuroQoL-5 Dimensions utility data and costs inflated to 2017 US dollars (US$) were from published literature. Results were discounted at 3.0% per annum. Deterministic and probabilistic sensitivity analyses explored uncertainty.

RESULTS

Betrixaban dominated enoxaparin, with savings of US$784 and increased QALYs of 0.017 per patient. In addition, betrixaban dominated enoxaparin across all sensitivity analyses, but was most sensitive to utilities and DT probabilities. Furthermore, probabilistic sensitivity analysis found that betrixaban was more cost-effective than enoxaparin at all willingness-to-pay thresholds.

CONCLUSION

Betrixaban can be considered cost-effective for nonsurgical patients with acute medical illness at risk of VTE, requiring longer VTE prophylaxis from hospitalization through post-discharge.

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.

Is thromboprophylaxis cost effective in ovarian hyperstimulation syndrome: A systematic review and cost analysis

BACKGROUND

The majority of serious thromboembolic events occurring in assisted reproductive technologies (ART) are in women with ovarian hyperstimulation syndrome (OHSS).

OBJECTIVES

The purpose of this study was to present a thorough review and cost analysis regarding the use of venous thromboembolism (VTE) prophylaxis in OHSS to inform clinical management.

DATA SOURCES

Databases used were Pubmed and Embase, in addition to checking reference lists of retrieved articles (inception to November 2017).

METHODS

The systematic search strategy identified 365 titles and abstracts. Articles included in the qualitative synthesis had identified venous thrombosis incidence rates or ratios. A separate search for the cost model was conducted recognizing all associated complications of VTE. The decision tree was modeled to best fit the patient population and a sensitivity analysis was performed over a range of variables.

RESULTS

The cost of VTE event per OHSS patient not on prophylaxis was €5940 (range €3405 to €38,727), versus €4134 (€2705 to €23,192) per event per patient on prophylaxis, amounting to a saving of (€19 to €23,192) per VTE per patient. Sensitivity analysis found VTE prophyaxis to be cost effective if the incidence of VTE in the OHSS population was greater than 2.79%. Prophylactic therapy was cost effective through 16 weeks of treatment.

LIMITATIONS

OHSS is infrequent and hence, the incidence of VTE in patients with OHSS is low; therefore, the data used to inform the incidence of VTE in OHSS in the model carry some uncertainty. Further, low molecular weight heparin (LMWH) has side effects therefore individualization of care must be considered.

CONCLUSIONS

With the increasing incidence of infertility and requirement for ART, thromboembolism in OHSS poses a major health threat for patients. VTE prophylaxis using enoxaparin was cost effective in patients with severe OHSS over a wide range of costs and incidences. Prophylaxis was also cost effective through the completion of the first trimester of pregnancy.

Postthrombotic Syndrome: Long-Term Sequela of Deep Venous Thrombosis

Postthrombotic syndrome is a common long-term complication of proximal lower extremity deep venous thrombosis, which not only significantly affects the quality of life of patients but also imposes a substantial financial burden on our healthcare system. Due to limited awareness and inability of physicians to recognize and treat this condition early, its prevalence is steadily increasing. In this article, we review the pathophysiology, the risk factors involved, diagnostic workup, and the various management options available to treat this condition.

Thrombosis: A major contributor to global disease burden

Thrombosis is a common pathology underlying ischaemic heart disease, ischaemic stroke, and venous thromboembolism (VTE). The Global Burden of Disease Study 2010 (GBD 2010) documented that ischaemic heart disease and stroke collectively caused one in four deaths worldwide. GBD 2010 did not report data for VTE as a cause of death and disability. We performed a systematic review of the literature on the global disease burden due to VTE in low, middle and high income countries. Studies from Western Europe, North America, Australia, and Southern Latin America (Argentina) yielded consistent results with annual incidences ranging from 0.75 to 2.69 per 1,000 individuals in the population. The incidence increased to between 2 and 7 per 1,000 among those 70 years of age or more. Although the incidence is lower in individuals of Chinese and Korean ethnicity, their disease burden is not low because of population aging. VTE associated with hospitalisation was the leading cause of disability-adjusted-lifeyears (DALYs) lost in low and middle income countries, and second in high income countries, responsible for more DALYs lost than nosocomial pneumonia, catheter-related blood stream infections, and adverse drug events. VTE causes a major burden of disease across low, middle, and high income countries. More detailed data on the global burden of VTE should be obtained to inform policy and resource allocation in health systems, and to evaluate if improved utilisation of preventive measures will reduce the burden.

Note: The copyright for the article is being held by the International Society on Thrombosis and Haemostasis under a CC-BY-NC-ND license.

Chronic complications of venous thromboembolism

Venous thromboembolism (VTE) is a common disease (~700 per 100 000) that is associated with significant risk of recurrence, chronic complications, and substantial mortality, with reported death rates of up to 40% at 10 years. The development of novel anticoagulants has revolutionized the treatment of acute VTE, while strategies for prevention and treatment of chronic complications still seek for such a landmark change. Impaired thrombus resolution is the common denominator behind VTE complications, which are postthrombotic syndrome (PTS) and chronic thromboembolic pulmonary hypertension (CTEPH). PTS and CTEPH are associated with substantial morbidity and high healthcare expenses. While PTS occurs in up to 50% of patients after symptomatic deep vein thrombosis, only a small and poorly defined number of patients are diagnosed with CTEPH after pulmonary embolism. This review is a comprehensive summary of VTE-related chronic complications, their epidemiology, diagnosis, and treatment.

Clinical and economic benefits of extended treatment with apixaban for the treatment and prevention of recurrent venous thromboembolism in Canada

Background and objective Venous thromboembolism (VTE) is associated with long-term clinical and economic burden. Clinical guidelines generally recommend at least 3 months of anticoagulation, but, in clinical practice, concerns over bleeding risk often limit extended treatment. Apixaban was studied for extended VTE treatment in the AMPLIFY-EXT trial, demonstrating superiority to placebo in VTE reduction without increasing risk of major bleeding. This study assessed the long-term clinical and economic benefits of extending treatment with apixaban when clinical equipoise exists compared to standard of care with enoxaparin/warfarin and other novel oral anti-coagulants (NOACs) for the treatment and prevention of recurrent VTE in Canada. Methods A Markov model was developed to follow patients with VTE over their lifetimes. Efficacy and safety for apixaban and enoxaparin/warfarin were based on AMPLIFY and AMPLIFY-EXT, while relative efficacy to other NOACs was synthesized by network meta-analysis (NMA). Dosages for NOACs and enoxaparin/warfarin were based on their respective trials and were given up to 18 months and up to 6 months, followed by no treatment, respectively. Patient quality adjusted life years (QALYs) were based on published studies, and costs for resource utilization were from a Ministry of Health perspective, expressed as 2014 CAD ($). Results Extended treatment with apixaban compared to enoxaparin/warfarin resulted in fewer recurrent VTEs, VTE-related deaths, and bleeding events, but at slightly increased cost. The incremental cost-effectiveness ratio was $4828 per QALY gained. Compared to other NOACs, apixaban had the fewest bleeding events, similar recurrent VTE events, and the lowest overall cost, which was driven by the strong bleeding profile. In scenario analyses of acute and lifetime treatments, apixaban was cost-effective against all strategies. Conclusions Extended treatment with apixaban can offer substantial clinical benefits and is a cost-effective alternative to enoxaparin/warfarin and other NOACs.

Engaging with quality improvement in anticoagulation management

Anticoagulants are highly effective at preventing thrombosis across a variety of clinical indications. However, their use can also lead to devastating effects, including major bleeding and death. Anticoagulation providers strive to balance the benefits of anticoagulant therapy with the risks of major bleeding. A measure of quality care can be used to assess the strengths and potential weaknesses in any system of coordinated care delivery. Quality measures in anticoagulation include patient-centered outcomes (e.g. major bleeding, time in the therapeutic range) and provider- or process-focused outcomes (e.g. compliance with guideline recommendations and response times to out-of-range laboratory values). Engaging in quality improvement activities allows anticoagulation providers to assess their own performance and identify areas for targeted interventions. This review summarizes the justification for engaging in quality improvement for anticoagulation management and describes a number of example programs. Interventions benefiting the management of both warfarin and the direct oral anticoagulants are included. The review also details potential quality measures and resources for any anticoagulation provider looking to begin a quality improvement process.

A Multicenter, Retrospective Study of the Effectiveness of the Trellis-8 System in the Treatment of Proximal Lower-Extremity Deep Vein Thrombosis

BACKGROUND

Deep vein thrombosis (DVT) occurs in up to 600,000 patients in the United States annually and can lead to long-term morbidity because of the post-thrombotic syndrome. The multicenter isolated-pharmacomechanical thrombolysis device (ISOL-8) study was designed to determine the safety and efficacy of the Trellis™-8 peripheral infusion system when used as the primary intervention to achieve DVT thrombolysis in patients with proximal lower-extremity occlusive DVT, and track the incidence and severity of the post-thrombotic syndrome (PTS) symptoms in patients 2 years after treatment.

METHODS

Data were collected retrospectively from 6 centers on patients treated with the Trellis-8 system, an isolated-pharmacomechanical thrombolysis device (IPMTD). Patients with occlusive lower-extremity DVT involving at least the iliac and/or common femoral vein were included. Patient demographics, medical history, procedure outcomes, complications, and follow-up venous duplex and Venous Clinical Severity Score (VCSS) were collected through 24 months. Data analysis of outcomes were performed at 1 and 12 months. A 24-month analysis was not performed because of the small number of patients for whom 24-month data could be collected.

RESULTS

A total of 151 limbs in 139 patients were treated with IPMTD. The mean ± standard deviation (SD) procedure time was 122.6 ± 63.4 min. Single session treatment was delivered in 69.9% (93 of 133) of cases. Occlusive DVT extended from the femoral into the external and/or common iliac vessel segments in most of the cases (113 of 151 limbs; 74.8%). Before treatment, 23.2% (35 of 151) of the treated limbs, based on a history of prior ipsilateral DVT or preoperative imaging revealing chronic venous scar, were expected to have some chronic venous disease despite presenting with acute symptoms. After treatment, 43.7% (66 of 151) of the limbs showed evidence of chronic thrombus. The average amount (mean ± SD) of thrombolysis, as determined by venogram, was highest in patients who had acute thrombus (81 ± 19.7%), compared with subacute thrombus (61 ± 22.5%) and complex cases involving acute and/or subacute thrombus on chronic scar (56 ± 26.5%). VCSS scoring showed the number of patients with none and/or mild pain, varicose veins, and skin changes at 1-month remained stable at 12 months whereas the percent of patients with none and/or mild venous edema improved from 71.7% at 1 month (38 of 53) to 86.8% (46 of 53) at 12 months. Twenty-four-month follow-up data were available for only 15% (23 of 151) of patients. No clinically significant pulmonary emboli or major periprocedural bleeding events were reported.

CONCLUSIONS

Patients with acute lower-extremity DVT involving the proximal veins can be safely and successfully treated with IPMTD. Major procedural bleeding was absent. The occurrence of severe PTS after primary treatment with Trellis-8 system IPMTD is low. Further long-term follow-up data are needed to confirm the benefit of intervention for thrombus removal compared with standard medical management.

Thrombosis: a major contributor to global disease burden

BACKGROUND

Thrombosis is the common pathology underlying ischemic heart disease, ischemic stroke, and venous thromboembolism (VTE). The Global Burden of Disease Study 2010 (GBD 2010) documented that ischemic heart disease and stroke collectively caused 1 in 4 deaths worldwide. GBD 2010 did not report data for VTE as a cause of death and disability.

OBJECTIVE

To review the literature on the global burden of disease caused by VTE.

APPROACH AND RESULTS

We performed a systematic review of the literature on the global disease burden because of VTE in low-, middle-, and high-income countries. Studies from Western Europe, North America, Australia, and Southern Latin America (Argentina) yielded consistent results with annual incidences ranging from 0.75 to 2.69 per 1000 individuals in the population. The incidence increased to between 2 and 7 per 1000 among those aged ≥70 years. Although the incidence is lower in individuals of Chinese and Korean ethnicity, their disease burden is not low because of population aging. VTE associated with hospitalization was the leading cause of disability-adjusted life-years lost in low- and middle-income countries, and second in high-income countries, responsible for more disability-adjusted life-years lost than nosocomial pneumonia, catheter-related blood stream infections, and adverse drug events.

CONCLUSIONS

VTE causes a major burden of disease across low-, middle-, and high-income countries. More detailed data on the global burden of VTE should be obtained to inform policy and resource allocation in health systems and to evaluate whether improved use of preventive measures will reduce the burden.

Thrombosis: a major contributor to global disease burden

Thrombosis is a common pathology underlying ischemic heart disease, ischemic stroke, and venous thromboembolism (VTE). The Global Burden of Disease Study 2010 (GBD 2010) documented that ischemic heart disease and stroke collectively caused one in four deaths worldwide. GBD 2010 did not report data for VTE as a cause of death and disability. We performed a systematic review of the literature on the global disease burden due to VTE in low, middle and high income countries. Studies from Western Europe, North America, Australia, and Southern Latin America (Argentina) yielded consistent results with annual incidences ranging from 0.75 to 2.69 per 1,000 individuals in the population. The incidence increased to between 2 and 7 per 1,000 among those 70 years of age or more. Although the incidence is lower in individuals of Chinese and Korean ethnicity, their disease burden is not low because of population aging. VTE associated with hospitalization was the leading cause of disability-adjusted-life-years (DALYs) lost in low and middle income countries, and second in high income countries, responsible for more DALYs lost than nosocomial pneumonia, catheter-related blood stream infections, and adverse drug events. VTE causes a major burden of disease across low, middle, and high income countries. More detailed data on the global burden of VTE should be obtained to inform policy and resource allocation in health systems, and to evaluate if improved utilization of preventive measures will reduce the burden.

Thrombosis: a major contributor to the global disease burden

Thrombosis is a common pathology underlying ischemic heart disease, ischemic stroke, and venous thromboembolism (VTE). The Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study 2010 documented that ischemic heart disease and stroke collectively caused one in four deaths worldwide. GBD 2010 did not report data for VTE as a cause of death and disability. We performed a systematic review of the literature on the global disease burden caused by VTE in low-income, middle-income and high-income countries. Studies from western Europe, North America, Australia and southern Latin America (Argentina) yielded consistent results, with annual incidence rates ranging from 0.75 to 2.69 per 1000 individuals in the population. The incidence increased to between 2 and 7 per 1000 among those aged ≥ 70 years. Although the incidence is lower in individuals of Chinese and Korean ethnicity, their disease burden is not low, because of population aging. VTE associated with hospitalization was the leading cause of disability-adjusted life-years (DALYs) lost in low-income and middle-income countries, and the second most common cause in high-income countries, being responsible for more DALYs lost than nosocomial pneumonia, catheter-related bloodstream infections, and adverse drug events. VTE causes a major burden of disease across low-income, middle-income and high-income countries. More detailed data on the global burden of VTE should be obtained to inform policy and resource allocation in health systems, and to evaluate whether improved utilization of preventive measures will reduce the burden.

Total Knee Arthroplasty Complicated by Distal Deep Venous Thromboembolism: Does it Affect the Functional Outcome?

The aim of this study is to determine the outcome of total knee arthroplasty (TKA) following patients with and without deep vein thrombosis (DVT) using patient-reported quality of life outcomes and therapist-reported knee range of motion. We carried out a retrospective study of 157 patients who underwent primary TKA at one large regional hospital. Thirty-six patients developed DVT after TKA. We scored patients at pre-operation, six months and two years post-operation using Short Form-36, Knee Society Clinical Rating System, Oxford 12-item Knee Score questionnaires, and knee range of motion. Our study found that there was no significant difference in the patient-reported quality of life outcomes and therapist-reported knee range of motion between patients who had developed DVT and those who did not.

New oral anticoagulants: prevention of VTE in phase III studies in total joint replacement surgery and the hospitalized medically-ill patients

Effective venous thromboembolism prophylaxis in hospitalized medically-ill patients and those undergoing orthopaedic surgery remains a challenge for clinicians in the United States. Several new oral anticoagulants, which either directly inhibit the activity of thrombin or factor Xa have been developed and studied for venous thromboembolism (VTE) prevention in phase III trials in these patient populations. These new medications demonstrate several advantages over traditional anticoagulants, including their administration at fixed doses with no requirement for routine coagulation monitoring. Such advantages may potentially be offset by the lack of well-studied methods to reverse their anticoagulant effects and the potential need for standardized testing to monitor their activity in certain situations. This review will provide an overview of the clinical trial results of dabigatran, apixaban and rivaroxaban for VTE prevention in the orthopaedic and medically-ill hospitalized patients.