Post-thrombotic syndrome after primary event of deep venous thrombosis 10 to 20 years ago

Graduated elastic compression stockings in the prevention of post-thrombotic syndrome: A systematic review and meta-analysis

BACKGROUND

The effect of graduated elastic compression stockings (ECS) in the prevention of post-thrombotic syndrome (PTS) has been questioned since a large randomized trial found no prophylactic effect of ECS.

OBJECTIVE

To assess the effect of the wearing time of ECS on the incidence of post-thrombotic syndrome (PTS) after proximal deep venous thrombosis, we performed a meta-analysis of the incidence of PTS across randomized and observational studies.

METHOD

PubMed, Embase and Cochrane databases were searched until 12 June 2023 for studies on the effect of ECS on PTS. References of eligible studies were also screened in order to identify other potential studies that might have been missed during the search.

RESULTS

Four studies comprising a total of 1467 patients met our inclusion criteria for early initiation and consistent use of ECS in patients with acute proximal DVT. ECS significantly reduced the incidence of mild-moderate PTS (OR: 0.48; 95% CI: 0.36-0.63) as well as severe PTS (OR: 0.44; 95% CI: 0.28-0.58).

Management of iliofemoral deep vein thrombosis with distal involvement

Endovascular treatment of iliofemoral deep vein thrombosis (IF DVT) can become more complex when thrombus extends below the knee. This article discusses various techniques that can be used to treat IF DVT with distal involvement.

Effects of Deep Venous Thrombosis Treatments on Early and Long-term Quality of Life: Medical Therapy vs. Systemic Thrombolysis vs. Pharmacomechanical Thrombolysis

OBJECTIVES

The present study aimed to compare the effects of medical therapy (MT), systemic thrombolysis (ST), and pharmacomechanical thrombolysis (PMT) methods used in our clinic for the treatment of deep venous thrombosis (DVT) on symptom reduction, the incidence of post-thrombotic syndrome (PTS) development, and quality of life.

METHODS

Data from160 patients diagnosed with acute DVT between January 2012 and May 2021 and treated and followed up in our clinic were retrospectively analyzed. The patients were divided into three groups according to treatment method. The patients who received MT treatment were defined as Group 1, anticoagulant treatment after ST as Group 2, and anticoagulant treatment after PMT as Group 3. The patients were called to the outpatient clinic, informed consent was obtained, EuroQol-5D-3 L (EQ-5D-3 L) scoring and Villalta scoring were performed, and anamnesis was taken.

RESULTS

A total of 160 patients were included, with 71 (44.4%) patients in Group 1, 45 (28.1%) in Group 2, and 44 (27.5%) in Group 3. The mean age was 48.9 ± 14.9 years for Group 1, 42.2 ± 10.8 for Group 2, and 29.0 ± 7.2 for Group 3. When the time to return to normal life and the EQ-5D-3 L score index were compared, the differences between Groups 1 and 2 and between Groups 1 and 3 were statistically significant (P = .000 and P = .000, respectively). However, the differences between Groups 2 and 3 were statistically insignificant (P = .213 andp = .074, respectively). When Villalta scores and EQ Visual Analogue Scale (EQ-VAS) scores were compared between groups, the difference between all groups was statistically significant (P = .000).

CONCLUSIONS

The medical treatment alone was observed to be insufficient in terms of symptomatic improvement, development of PTS, quality of life, and long-term complications. When the ST and PMT groups were compared, it was determined that PMT treatment was more advantageous in terms of EQ-VAS score and PTS development, although there was no statistical difference regarding complications, such as return to normal life and long-term quality of life, the incidence of recurrent DVT development, and pulmonary thromboembolism incidence.

Epidemiology and Diagnosis of Post-Thrombotic Syndrome: Qualitative Synthesis with a Systematic Review

Background: Post-thrombotic syndrome (PTS) is a common and debilitating sequela of lower limb deep vein thrombosis (DVT). There is significant heterogeneity in reported PTS incidence due to lack of standardised diagnostic criteria. This review aimed to develop diagnostic criteria for PTS and subsequently refine the reported incidence and severity. Methods: PRISMA principles were followed; however, the review was not registered. The Cochrane CENTRAL database, MEDLINE, Embase, the NHS NICE Healthcare Databases Advanced Search interface, and trial registers including isrctn.com and clinicaltrials.gov were searched for studies addressing areas of interest (PTS definition, epidemiology, assessment). An experienced Clinical Librarian undertook the systematic searches, and two independent reviewers agreed on the relevance of the papers. Conflicts were resolved through panel review. Evidence quality was assessed using a modified Coleman scoring system and weighted according to their relevance to the aforementioned areas of interest. Results: A total of 339 abstracts were retrieved. A total of 33 full-text papers were included in this review. Following qualitative analysis, four criteria were proposed to define PTS: (1) a proven thrombotic event on radiological assessment; (2) a minimum 24-month follow-up period after an index DVT; (3) assessment with a validated score; and (4) evidence of progression of venous insufficiency from baseline. Four papers conformed to our PTS definition criteria, and the incidence of mild to moderate PTS ranged from 7 to 36%. On reviewing the studies which utilised the recommended Villalta scale, PTS incidence narrowed further to 23-36%. Incidence and severity reached a plateau at 24 months. Conclusions: Four diagnostic criteria were developed from qualitative synthesis. When these criteria were applied to the literature, the range of reported PTS incidence narrowed. These four criteria may standardise PTS diagnosis in future studies, facilitating the pooling of data for meta-analysis and synthesis of higher levels of evidence.

The risk for post-thrombotic syndrome of subjects with deep vein thrombosis in an Indonesian referral hospital: a retrospective cohort study

BACKGROUND

Post-thrombotic syndrome (PTS) is a complication of deep vein thrombosis (DVT) and affects 20-40% of DVT subjects. The risk factor of PTS after DVT is difficult to determine. We aimed to evaluate the incidence of PTS after 3 months of DVT diagnosis and to determine the risk of PTS.

METHODS

A retrospective cohort study of subjects who developed DVT confirmed by Doppler ultrasound in Cipto Mangunkusumo Hospital from April 2014 until June 2015. The presence of PTS was assessed after 3 months of completed DVT treatment using the Villalta score. Risk factors for PTS were evaluated from medical records.

RESULTS

There were 91 subjects with DVT with mean age of 58 years. 56% were female. It was dominated by subjects aged ≥ 60 years (45.1%). Hypertension (30.8%) and diabetes mellitus (26.4%) were the major comorbidities in this study. Deep vein thrombosis occurred commonly in unilateral side (79.1%), proximal localization (87.9%), and unprovoked DVT (47.3%). The cumulative incidence of PTS after DVT was 53.8%, 69% of subjects had mild PTS. Heaviness of the leg (63.2%) and edema (77.5%) were the most common symptoms.

RESULTS

There were 91 subjects with DVT with mean age of 58 years. 56% were female. It was dominated by subjects aged ≥ 60 years (45.1%). Hypertension (30.8%) and diabetes mellitus (26.4%) were the major comorbidities in this study. Deep vein thrombosis occurred commonly in unilateral side (79.1%), proximal localization (87.9%), and unprovoked DVT (47.3%). The cumulative incidence of PTS after DVT was 53.8%, 69% of subjects had mild PTS. Heaviness of the leg (63.2%) and edema (77.5%) were the most common symptoms. Significant risk factors for PTS were unprovoked DVT (adjusted RR 1.67; 95%CI: 1.17-2.04; p = 0.01) and female gender (adjusted RR 1.55; 95%CI: 1.03-1.94; p = 0.04). Age, body mass index, thrombus location, immobilization, malignancy and surgery was not associated with PTS.

CONCLUSION

We conclude that 53.8% of subjects suffered PTS after 3 months of DVT. Unprovoked DVT and female gender were significant risk factors for PTS.

Postthrombotic syndrome and quality of life after deep vein thrombosis in patients treated with edoxaban versus warfarin

Background

Postthrombotic syndrome (PTS) is a long-term complication after deep vein thrombosis (DVT) and can affect quality of life (QoL). Pathogenesis is not fully understood but inadequate anticoagulant therapy with vitamin K antagonists is a known risk factor for the development of PTS.

Objectives

To compare the prevalence of PTS after acute DVT and the long-term QoL following DVT between patients treated with edoxaban or warfarin.

Methods

We performed a long-term follow-up study in a subset of patients with DVT who participated in the Hokusai-VTE trial between 2010 and 2012 (NCT00986154). Primary outcome was the prevalence of PTS, defined by the Villalta score. The secondary outcome was QoL, assessed by validated disease-specific (VEINES-QOL) and generic health-related (SF-36) questionnaires.

Results

Between 2017 and 2020, 316 patients were enrolled in 26 centers in eight countries, of which 168 (53%) patients had been assigned to edoxaban and 148 (47%) to warfarin during the Hokusai-VTE trial. Clinical, demographic, and thrombus-specific characteristics were comparable for both groups. Mean (SD) time since randomization in the Hokusai-VTE trial was 7.0 (1.0) years. PTS was diagnosed in 85 (51%) patients treated with edoxaban and 62 (42%) patients treated with warfarin (adjusted odds ratio 1.6, 95% CI 1.0-2.6). Mean differences in QoL scores between treatment groups were not clinically relevant.

Conclusion

Contrary to our hypothesis, the prevalence of PTS tended to be higher in patients treated with edoxaban compared with warfarin. No differences in QoL were observed. Further research is warranted to unravel the role of anticoagulant therapy on development of PTS.

MiR-150 promotes angiogensis and proliferation of endothelial progenitor cells in deep venous thrombosis by targeting SRCIN1

Venous thromboembolism (VTE), encompassing deep venous thrombosis (DVT) and pulmonary embolism (PE), is the third most common cardiovascular disease. miR-150 is one of important microRNAs which play critical role in various cellular function such as endothelial progenitor cells (EPCs). In this study, we investigate the effect of miR-150 on EPCs function ex vivo and thrombus resolution in vivo. We determined miR-150 expression in EPCs isolated from DVT patients and control subjects by RT-PCR. Potential target of miR-150 was confirmed by bioinformatics analysis and luciferase reporter respectively. The angiogenesis and proliferation were tested by MTT and tube formation assay. A murine model of venous thrombosis was developed as in vivo model. Finally, the effect of miR-150 on EPCs with inferior venous thrombosis were evaluated in vivo. Our data showed that miR-150 was downregulated in EPCs from DVT patients. By using miR-150 agomir and antagomir, we found that miR-150 promoted angiogenesis and proliferation of EPCs. Bioinformatics analysis revealed SRCIN1 as a target of miR-150 and SRCIN1 knockdown inhibited function of EPCs. Forced expression of miR-150 contributed thrombus resolution in a murine model of venous thrombosis. In general, miR-150 was downregulated in EPCs from DVT. Upregulation of miR-150 promoted angiogenesis and proliferation of EPCs by targeting SRCIN1 in vitro and thrombus resolution in vivo.

Receiver array design for sonothrombolysis treatment monitoring in deep vein thrombosis

High intensity focused ultrasound (HIFU) can disintegrate blood clots through the generation and stimulation of bubble clouds within thrombi. This work examined the design of a device to image bubble clouds for monitoring cavitation-based HIFU treatments of deep vein thrombosis (DVT). Acoustic propagation simulations were carried out on multi-layered models of the human thigh using two patient data sets from the Visible Human Project. The design considerations included the number of receivers (32, 64, 128, 256, and 512), their spatial positioning, and the effective angular array aperture (100° and 180° about geometric focus). Imaging array performance was evaluated for source frequencies of 250, 750, and 1500 kHz. Receiver sizes were fixed relative to the wavelength (pistons, diameter  =  λ/2) and noise was added at levels that scaled with receiver area. With a 100° angular aperture the long axis size of the  -3 dB main lobe was ~1.2λ-i.e. on the order of the vessel diameter at 250 kHz (~7 mm). Increasing the array aperture to span 180° about the geometric focus reduced the long axis by a factor of ~2. The smaller main lobe sizes achieved by imaging at higher frequencies came at the cost of increased levels of sensitivity to phase aberrations induced during acoustic propagation through the intervening soft tissue layers. With noise added to receiver signals, images could be reconstructed with peak sidelobe ratios  <  -3 dB using single-cycle integration times for source frequencies of 250 and 750 kHz (NRx  ⩾  128). At 1500 kHz, longer integration times and/or higher element counts were required to achieve similar peak sidelobe ratios. Our results suggest that a modest number of receivers(i.e. NRx  =  128) arranged on a semi-cylindrical shell may be sufficient to enable passive acoustic imaging with single-cycle integration times (i.e. volumetric rates up to 0.75 MHz) for monitoring cavitation-based HIFU treatments of DVT.

Rivaroxaban or vitamin-K antagonists following early endovascular thrombus removal and stent placement for acute iliofemoral deep vein thrombosis

BACKGROUND

The optimal anticoagulant following catheter-based therapy of acute iliofemoral deep vein thrombosis (IFDVT) is unknown.

METHODS

From the Swiss Venous Stent registry, an ongoing prospective cohort study, we performed a subgroup analysis of patients with acute IFDVT who underwent catheter-based early thrombus removal followed by nitinol stent placement. Duplex ultrasound and Villalta scores were used to determine patency rates and incidence of the post-thrombotic syndrome (PTS) in patients treated with either rivaroxaban (n = 73) or a vitamin K-antagonist (VKA; n = 38) for a minimum duration of 3 months.

RESULTS

Mean follow-up duration was 24 ± 19 months (range 3 to 77 months). Anticoagulation therapy was time-limited (3 to 12 months) in 56% of patients (47% in the rivaroxaban group and 58% in the VKA group, p = 0.26), with shorter mean duration of anticoagulation in the rivaroxaban group (180 ± 98 days versus 284 ± 199 days, p = 0.01). Overall, primary and secondary patency rates at 24 months were 82% (95%CI, 71-89%) and 95% (95%CI, 87-98%), respectively, with no difference between the rivaroxaban (87% [95%CI, 76-94%] and 95% [95%CI, 85-98%]) and the VKA group (72% [95%CI, 52-86%] and 94% [95%CI, 78-99%]; p > 0.10 for both). Overall, 86 (86%) patients were free from PTS at latest follow-up, with no difference between the rivaroxaban and the VKA groups (57 [85%] versus 29 [88%]; p = 0.76). Two major bleeding complications (1 in each group) occurred in the peri-interventional period, without any major bleeding thereafter.

CONCLUSIONS

In patients with acute IFDVT treated with catheter-based early thrombus removal and venous stent placement, the effectiveness and safety of rivaroxaban and VKA appear to be similar.

CLINICAL TRIAL REGISTRATION

The study is registered on the National Institutes of Health website (ClinicalTrials.gov; identifier NCT02433054).

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).

Health-related quality of life after adverse bleeding events associated with antithrombotic drug therapy - A systematic review

Little is known about the health-related quality of life (HRQOL) following adverse bleeding events associated with antithrombotic drug therapy. This systematic review assesses the HRQOL of patients who suffered a bleeding event related to antithrombotic drug use. A literature search was performed using PubMed, EMBASE, and the Cochrane Library from inception through June 16, 2017. Studies measuring HRQOL after a bleeding event related to antithrombotic drug therapy for primary or secondary prevention of a thromboembolic event were included. Four studies with a total of 13,209 patients met the inclusion criteria, and of them, 3,649 patients developed a bleeding event. Patients who were included received antithrombotic drugs because of acute myocardial infarction or atrial fibrillation. EQ-5D, SF-36, and GHP MOS-13 were used to measure HRQOL. The follow-up time ranged from 6 to 29 months. Patients who suffered a bleeding event reported worse HRQOL compared to those who did not (EQ-5D - average increase on all domains of 0.09, p-values ranging from <0.001 to 0.003; SF-36 - average decrease on all domains of 21.4, p < 0.001; and GHP MOS-13 score - decrease of 11.9 points, p < 0.05) and an increased health concern (13.4-point increase; p < 0.05). In conclusion, adverse bleeding events occurring because of the use of antithrombotic agents are associated with a clinically relevant lower HRQOL and hence deserve more attention as part of the shared decision-making process between patients and providers. These data should be valuable for facilitating more substantive care and risk discussions regarding potential changes in outcome and rehabilitation.

Prevention and treatment of the post-thrombotic syndrome

Post thrombotic syndrome (PTS) is a common chronic complication of deep vein thrombosis of the leg (DVT). Treatment options are limited therefore emphasis is placed on its prevention. Several risk factors have been recognized, but were so far not used for risk stratification or translation into prediction models. Early interventions did not yet result in more successful preventive treatment strategies; for the acute phase of DVT there is equipoise on the value of elastic compression, as well as on catheter directed thrombolysis. There are no drugs specifically targeted at PTS prevention. The use of anticoagulant medication such as direct oral anticoagulants (DOACs) might decrease PTS incidence, but this needs to be corroborated. Both research into more effective treatment options as well as future PTS management may benefit from a uniform diagnostic strategy and the use of prediction rules to better allocate treatment and thereby increase treatment efficacy.

Epidemiology of the post-thrombotic syndrome

The post thrombotic syndrome (PTS) refers to clinical manifestations of chronic venous insufficiency (CVI) following a deep-vein thrombosis (DVT). PTS is the most frequent complication of DVT, which develops in 20 to 50% of cases after proximal DVT and is severe in 5-10% of cases. The reported prevalence of PTS differs widely among studies because of differences in study populations, tools used to assess PTS, and time interval between acute DVT and PTS assessment. The two most important predictors of PTS are extensive proximal character of DVT and previous ipsilateral DVT. Other reported risk factors include pre-existing CVI, obesity, quality of anticoagulant treatment, older age and residual venous obstruction. Standardization of PTS assessment tools combined with the development of patient self-reported PTS scales are likely to constitute a breakthrough in research of the epidemiology of PTS, by allowing comparison between studies, meta-analyses and increasing the feasibility of longer follow-up of DVT patients. This should enable identification of patient populations at high risk of severe PTS, new predictors of PTS and targets for potential new treatments. In this perspective, identification of biomarkers that are predictive of PTS such as markers of inflammation is crucial in ongoing research.

Impact of optimal anticoagulation therapy on chronic venous ulcer healing in thrombophilic patients with post-thrombotic syndrome

OBJECTIVE

Post-thrombotic syndrome (PTS) is the long-term sequelae of deep venous thrombosis (DVT). PTS clinical manifestations include chronic leg pain, oedema, lipodermatosclerosis and ulcers. The objective of this study is to determine in patients with documented history of thrombophilias and DVT whether the number of previous thrombotic events and optimal anticoagulation therapy are associated with the time to venous ulcer healing following the start of compression therapy.

METHOD

Retrospective analysis performed in thrombophilic patients under the age of 50 years old with chronic venous ulcers secondary to DVT at the wound clinic in the National Institute of Medical Sciences and Nutrition 'Salvador Zubirán ' in Mexico City. Variables such as the number or episodes of thrombotic events, type of hypercoagulable disorder, optimal anticoagulation therapy with Warfarin monitored by therapeutic International Normalised Ratio (INR) (2-3) and compliance to compression therapy were examined. Patients that underwent superficial or perforator vein interruption or endovascular recanalisation of deep veins were excluded from the study.

RESULTS

From a database of 29 patients with chronic venous ulcers followed in our clinic from January 1992 to September 2012, only 13 patients (61% female) met the inclusion criteria. Mean age±standard deviation (SD) was 32±12 years old. Of these, seven (54%) patients with suboptimal INR presented with an average of two previous thrombotic events and the remaining six (46%) patients with optimal INR only one event (p=0.28), the mean time to the clinical manifestation of a venous ulcer after the first episode of DVT was 39 months (range: 12-72) for patients with suboptimal INR and 82 months (range: 12-216) for those with optimal anticoagulation therapy (p=0.11). During the mean follow-up period of 52 months, all patients in optimal anticoagulation healed their ulcer; their mean time for wound healing was 44 months (range: 4-102). In the suboptimal INR group, only four healed the ulcers with an mean of 72 months (range: 2-204) (p=0.94).

CONCLUSION

There seems to be an association between an optimal anticoagulation therapy with Warfarin monitored by INR and wound healing rates in thrombophilic patients with chronic venous ulcers. Further research is warranted.

DECLARATION OF INTEREST

The authors have no conflict of interest.

Contemporary management of acute and chronic deep venous thrombosis

INTRODUCTION

This review aims to provide an update on the management of deep vein thrombosis (DVT).

SOURCES OF DATA

A systematic search of PubMed, Google Scholar and Cochrane databases was carried out.

AREAS OF AGREEMENT

Direct oral anticoagulants (DOACs) are as effective and easier to use than vitamin K antagonists for the treatment of DVT. Catheter-directed thrombolysis can reduce post thrombotic syndrome in patients with iliofemoral DVT. Compression bandaging can help heal a venous ulcer.

AREAS OF CONTROVERSY

Compression hosiery to prevent post thrombotic syndrome. Long-term evidence to show clinical benefit of using endovenous therapies to restore deep vein patency.

GROWING POINTS

Developing imaging methods to identify patients who would benefit from venous thrombolysis. The evolution of dedicated venous stents.

AREAS TIMELY FOR DEVELOPING RESEARCH

Understanding the mechanisms that lead to stent occlusion and investigation into the appropriate treatments that could prevent in-stent thrombosis is required.

Analysis of 1,338 Patients with Acute Lower Limb Deep Venous Thrombosis (DVT) Supports the Inadequacy of the Term "Proximal DVT"

OBJECTIVE/BACKGROUND

For decades acute lower limb deep venous thrombosis (DVT) has been subdivided into distal DVT (isolated to the calf veins) and proximal DVT (extending above calf vein level). The aim of this study was to analyse the anatomical site and extent of thrombus in a large cohort of patients with acute DVT.

METHODS

A retrospective analysis of all patients aged >18 years, presenting with unilateral DVT according to duplex ultrasound investigation was performed at the University Hospital of Antwerp, Belgium (1994-2012). The anatomical site and extent of thrombus was registered and subdivided into five segments: calf veins (segment 1), popliteal vein (segment 2), femoral vein (segment 3), common femoral vein (segment 4), and iliac veins, with or without inferior vena cava (segment 5).

RESULTS

The median age of the 1,338 patients (50% male) included was 62 years (range 18-98 years). Left sided DVT was predominant (57%). DVT was limited to one segment in 443 patients, of whom 370 had DVT isolated to the calf veins (28% of total cohort). In 968 patients with what was previously called "proximal DVT", the median number of affected segments was three (range 1-5 segments). In this group iliofemoral DVT (at least involving segment four and/or five) was present in 506 patients (38% of total cohort), whereas the remaining patients had femoropopliteal DVT (at least in segment two and/or three but not in four or five). Iliofemoral DVT without thrombus in segments one and two was present in 160 patients (12% of total cohort).

CONCLUSION

This study illustrates the large diversity of thrombus distribution in patients previously described as having "proximal DVT". Therefore, this term should be abandoned and replaced with iliofemoral and femoropopliteal DVT. Patients with iliofemoral DVT (38%) could be considered for early clot removal; 12% of all patients with DVT would be ideal candidates for such intervention.

[Recanalisation therapy of deep leg and pelvic vein thrombosis]

The conservative treatment of deep leg and pelvic vein thrombosis leads to permanent damage of recanalised veins, which in cases of long distance clots as well as involvement of the pelvic level, increase the risk of developing a postthrombotic syndrome. Such subsequent damage of the deep veins can only be avoided if occluded veins are rapidly recanalised and the function of the valves is successfully reestablished. Recanalisation may consist of surgical, fibrolytic and interventional methods and aims to minimize any subsequent damage; however no potential benefit of recanalisation versus standard treatment has yet been proven by means of methodologically adequate comparative studies. Thus, the indications for recanalisation must remain strict and be founded on a thorough risk-benefit assessment.

Haematological considerations in urology: A systematic review

Deep venous thrombosis (DVT) remains a serious and common complication of surgical procedures and is therefore an issue of importance for all urologists. In the UK, pulmonary embolism (PE) following DVT in hospitalised patients causes 32,000 deaths each year. DVT and PE represent the outcome of venous thromboembolism (VTE). The total cost for management of VTE in 2005 was approximately ₤640 million. Early risk assessment and optimising modifiable risks are paramount in order to reduce the incidence of VTE. In this article we review common risk factors for VTE and emphasise specific risk factors for urological procedures. The perioperative management of urological patients who are chronically anticoagulated is discussed. We review the literature regarding anticoagulation and its relevance to all urological procedures and mention the problems associated with new anticoagulant agents. All urologists should be familiar with the new range of anticoagulant agents due to the increasing number of patients taking them.

Efficacy of a short course of complex lymphedema therapy or graduated compression stocking therapy in the treatment of post-thrombotic syndrome

Treatment options for established post-thrombotic syndrome (PTS) are limited. Complex lymphedema therapy (CLT), a non-invasive treatment that improves lymphatic flow, may have the potential to improve PTS. We conducted a single-center, investigator-blind, randomized controlled trial of 31 patients with a clinically established diagnosis of PTS and compared the efficacy of graduated compression stockings alone (30-40 mmHg) with CLT, a treatment that includes compression stockings, exercise, patient education, skin care and lymphatic drainage. Primary outcomes were the 1- and 3-month changes in PTS severity by the Villalta score and disease-specific quality of life using the VEINES-QOL (Venous Insufficiency Epidemiological and Economic Study Quality of Life) questionnaire. Analysis was by intent-to-treat. We found from a baseline average score of 9.9 points, CLT reduced mean PTS severity scores by -2.4 points (p=0.02) at the 1-month and -2.3 points (p=0.05) at the 3-month follow-up. Score reductions with stockings only were similar at -2.1 (p=0.03) and -3.3 points (p=0.03) at 1 and 3 months. The differences in score between treatments were not significant. Neither treatment significantly changed the VEINES-QOL score except in patients with severe disease. Patients with moderate to severe PTS derived the greatest benefit from either therapy and the two therapies differentially impacted PTS signs and symptoms. We found a short course of lymphedema therapy and compression stockings offer similar benefit in patients with PTS; however, larger studies are needed to further explore the potential use of CLT in PTS, particularly in patients with more severe disease. ClinicalTrials.gov Identifier: NCT00633971.

Impact of graduated compression stockings on the prevention of post-thrombotic syndrome - results of a randomized controlled trial

OBJECTIVE

Post-thrombotic syndrome is a chronic complication of acute deep venous thrombosis in the lower extremity. The role of graduated compression stockings in the prevention of post-thrombotic syndrome has been studied with opinion being divided on the beneficial effects. We aim to answer this question with a randomized controlled study that uses multiple scoring instruments to assess post-thrombotic syndrome.

METHODS

Sixty-nine consecutive patients with acute deep venous thrombosis diagnosed by duplex ultrasonography were randomized to treatment with graduated compression stockings or no graduated compression stockings. Venous Clinical Severity Score and Villalta-Prandoni Score, commonly used scoring systems, were used to appraise post-thrombotic syndrome at 3, 6, 12, 18, and 24 months following diagnosis of deep venous thrombosis. In both scoring systems, the individual either had post-thrombotic syndrome or no post-thrombotic syndrome. Cumulative incidence was computed using Kaplan-Meier analysis. Relative risk was assessed for age, obesity, varicose veins, and iliofemoral deep venous thrombosis.

RESULTS

As measured by both Villalta-Prandoni Score and Venous Clinical Severity Score instruments, the graduated compression stockings group had a lower incidence of post-thrombotic syndrome compared to the control group, but only when one month was used as cut off time for the first diagnosis of post-thrombotic syndrome. When 6 or 12 months were used, there was no difference in the incidence of post-thrombotic syndrome between the two groups. The burden of post-thrombotic syndrome was significantly more when the Villalta-Prandoni Score instrument (∼75%) was used as compared to the Venous Clinical Severity Score instrument (∼30%) at 24 months' follow-up. Obesity was the only statistically significant predictor for the development of post-thrombotic syndrome.

CONCLUSION

As assessed by both Villalta-Prandoni Score and Venous Clinical Severity Score instruments, use of graduated compression stockings does not reduce the incidence of post-thrombotic syndrome. There is a significant difference in the incidence post-thrombotic syndrome as detected by Villalta-Prandoni Score and Venous Clinical Severity Score instruments with incidence of post-thrombotic syndrome dependent on instrument and cut off time interval used to assess post-thrombotic syndrome. However, larger prospective studies are required to confirm these differences.

What predicts outcome after recanalization of chronic venous obstruction: hemodynamic factors, stent geometry, patient selection, anticoagulation or other factors?

In this review we evaluated the effect of different suggested factors associate with the outcome after recanalization of chronic venous obstruction (CVO).

Hemodynamic factors:

Based upon literature no clear suggestions can be made to identify the risk of stent occlusion in association with the hemodynamic effects. However it is evident that ensuring optimal in- and outflow of the stented tract is key in maintaining the patency.

Patient selection:

Noninvasive imaging modalities are used to divide patients in three subgroups based on the place and extension of post-thrombotic changes. Moreover it should be noted that AV fistula in selected patients can reduce the risk of thrombosis or re-occlusion.

Geometry:

Excessive oversizing of the stent and stent compression from outside are considered to be associated with stent occlusion. Additionally, overlapping rigid stents, unnatural angel between stents and in-stent kinking are other geometrical factors related to worse outcome after venous recanalization.

Anticoagulation:

Adequate peri-and postoperative anticoagulation has a crutial role in stent patency. There is no data regarding the duration of anticoagulation therapy and recommendations vary between 6 weeks to 6 months.

Result:

impaired inflow or outflow, presence of a hypercoagulability, total number of treated segments and use of stents designed for implantation in arterial system are associated with decreased stent patency.

Post-thrombotic syndrome 3 years after deep venous thrombosis in the Thrombosis and Pulmonary Embolism in Out-Patients (TULIPA) PLUS Registry

BACKGROUND

Reported post-thrombotic syndrome (PTS) rates may be confounded by including patients with a history of deep venous thrombosis (DVT) before the index event, varicose veins, or chronic venous insufficiency independent of PTS. We were interested in assessing PTS incidence rates of patients without these pre-existing disease conditions.

METHODS

A prospective registry with a 3-year follow-up after an initial DVT was assessed. Available for analysis were 135 ambulatory patients without a history of DVT (before the index DVT), signs of varicose veins, or chronic venous insufficiency affecting the ipsilateral or contralateral leg, and Villalta score.

RESULTS

PTS was detected in 24.5% of patients, with 17.0% having mild (Villalta score, 5-9), 6.0% moderate (score, 10-14), and 1.5% severe PTS (score ≥15) after a first DVT. Of these, 52.6% had proximal and 47.4% distal DVT; 63.7% were provoked and 35.6% unprovoked (one patient missing). Patients with proximal DVT (32.4%) significantly more often developed any PTS compared with patients with distal DVT (15.6%; P = .024); however, groups were similar with regard to severity of PTS by the four-level Villalta score (P = .109). In univariate analysis, PTS was more frequent (odds ratio, 95% confidence interval) with higher age (1.06 per year; 1.02-1.09), a body mass index of 25 to 30 kg/m(2) (2.38; 0.71-7.97) and ≥30 kg/m(2) (6.08; 1.75-21.14), proximal vs distal DVT (2.59; 1.12-5.98), and calf swelling ≥3 cm larger than the asymptomatic leg (3.77; 1.66-8.55). In a multivariate analysis, age (1.05; 1.01-1.09) and calf swelling ≥3 cm larger than the asymptomatic leg (2.94; 1.20-7.20) remained predictive for PTS. Compression therapy was used by 78.5% of patients at the 1-year follow-up and by 46.7% at the 3-year follow-up. Both rates were higher in patients with PTS (93.9%) vs no PTS (66.7%).

CONCLUSIONS

This prospective survey demonstrates a low rate of PTS in patients with a first DVT and no pre-existing DVT, varicose veins, or chronic venous insufficiency, and a high adherence rate to compression therapy, within the first 3 years of follow-up. Age and marked calf swelling were independent predictors of PTS.

Value-of-information analysis to reduce decision uncertainty associated with the choice of thromboprophylaxis after total hip replacement in the Irish healthcare setting

BACKGROUND

The National Centre for Pharmacoeconomics, in collaboration with the Health Services Executive, considers the cost effectiveness of all new medicines introduced into Ireland. Health Technology Assessments (HTAs) are conducted in accordance with the existing agreed Irish HTA guidelines. These guidelines do not specify a formal analysis of value of information (VOI).

OBJECTIVE

The aim of this study was to demonstrate the benefits of using VOI analysis in decreasing decision uncertainty and to examine the viability of applying these techniques as part of the formal HTA process for reimbursement purposes within the Irish healthcare system.

METHOD

The evaluation was conducted from the Irish health payer perspective. A lifetime model evaluated the cost effectiveness of rivaroxaban, dabigatran etexilate and enoxaparin sodium for the prophylaxis of venous thromboembolism after total hip replacement. The expected value of perfect information (EVPI) was determined directly from the probabilistic analysis (PSA). Population-level EVPI (PEVPI) was determined by scaling up the EVPI according to the decision incidence. The expected value of perfect parameter information (EVPPI) was calculated for the three model parameter subsets: probabilities, preference weights and direct medical costs.

RESULTS

In the base-case analysis, rivaroxaban dominated both dabigatran etexilate and enoxaparin sodium. PSA indicated that rivaroxaban had the highest probability of being the most cost-effective strategy over a threshold range of &U20AC;0-&U20AC;100 000 per QALY. At a threshold of &U20AC;45 000 per QALY, the probability that rivaroxaban was the most cost-effective strategy was 67%. At a threshold of &U20AC;45 000 per QALY, assuming a 10-year decision time horizon, the PEVPI was &U20AC;11.96 million and the direct medical costs subset had the highest EVPPI value (&U20AC;9.00 million at a population level). In order to decrease uncertainty, a more detailed costing study was undertaken. In the subsequent analysis, rivaroxaban continued to dominate both comparators. In the PSA, rivaroxaban continued to have the highest probability of being optimal over the threshold range &U20AC;0-&U20AC;100 000 per QALY. At &U20AC;45 000 per QALY, the probability that rivaroxaban was the most cost-effective strategy increased to 80%. At &U20AC;45 000 per QALY, the 10-year PEVPI decreased to &U20AC;3.58 million and the population value associated with the direct medical costs fell to &U20AC;1.72 million.

CONCLUSION

This increase in probability of cost effectiveness, coupled with a substantially reduced potential opportunity loss could influence a decision maker's confidence in making a reimbursement decision. On discussions with the decision maker we now intend to incorporate the use of VOI into our HTA process.

Risk of post-thrombotic syndrome after subtherapeutic warfarin anticoagulation for a first unprovoked deep vein thrombosis: results from the REVERSE study

BACKGROUND

Risk factors for post-thrombotic syndrome (PTS) remain poorly understood.

OBJECTIVES

In this multinational multicenter study, we evaluated whether subtherapeutic warfarin anticoagulation was associated with the development of PTS.

METHODS

Patients with a first unprovoked deep venous thrombosis (DVT) received standard anticoagulation for 5-7 months and were then assessed for PTS. The time in the therapeutic range was calculated from the international normalized ratio (INR) data. An INR below 2, more than 20% of the time, was considered as subtherapeutic anticoagulation.

RESULTS

Of the 349 patients enrolled, 97 (28%) developed PTS. The overall frequency of PTS in patients with subtherapeutic anticoagulation was 33.5%, compared with 21.6% in those with an INR below two for ≤ 20% of the time (P = 0.01). During the first 3 months of therapy, the odds ratio (OR) for developing PTS if a patient had subtherapeutic anticoagulation was 1.78 (95% confidence interval [CI] 1.10-2.87). After adjusting for confounding variables, the OR was 1.84 (95% CI 1.13-3.01). Corresponding ORs for the full period of anticoagulation were 1.83 (95% CI 1.14-3.00) [crude] and 1.88 (95% CI 1.15-3.07) [adjusted].

CONCLUSION

Subtherapeutic warfarin anticoagulation after a first unprovoked DVT was significantly associated with the development of PTS.

Endovascular treatment for post-thrombotic syndrome. Two case studies and a literature review

The recent application of endovascular treatment techniques to venous pathologies has meant that new therapeutic solutions can be offered to patients suffering from post-thrombotic syndrome. This often-underestimated condition frequently complicates cases of deep vein thrombosis, whether treated or not, leading to a chronic and disabling set of clinical symptoms (oedema, claudication, pain, venous ulcers, etc.) due to the combination of the pathophysiological phenomena of obstructions and reflux. These clinical signs see only minimal improvement when managed with the classic medical treatment, venotonic agents, and venous compression. We report the cases of two patients suffering with chronic post-thrombotic venous obstruction of the lower limbs in whom endovascular treatment brought clear and long-lasting clinical improvement.

Incidence and Risk Factors of the Post-thrombotic Syndrome

Annually 1–2 in every 1000 adults will develop a deep venous thrombosis of the lower extremity. A third to half of these patients will develop the post-thrombotic syndrome (PTS). However, predicting which patients will develop the PTS remains elusive. Ipsilateral thrombosis recurrence seems to be the most important risk factor. Moreover, residual venous occlusion and valvular reflux seem to predict PTS incidence to some degree. Laboratory parameters, including D-dimers and inflammatory markers, have shown promise in predicting development of the PTS in patients and are currently under investigation. Creating a model based on all combined risk factors and patient characteristics might aid in risk stratification in individual patients.

Pathophysiology of Post-Thrombotic Syndrome: The Effect of Recurrent Venous Thrombosis and Inherited Thrombophilia

Post-thrombotic syndrome is an important chronic complication of deep vein thrombosis. This syndrome can be debilitating to patients and has a major economic impact on health care services. The pathophysiology of post-thrombotic syndrome is currently incompletely understood. Because therapeutic options for post-thrombotic syndrome are extremely limited and results are often disappointing, recognizing of the pathophysiology and risk factors of this syndrome is essential to prevent the disabling consequences of this disease. The present paper focuses on risk determinants of post-thrombotic syndrome after deep vein thrombosis. The contribution of recurrent venous thrombosis and inherited thrombophilia to the pathogenesis of this syndrome is reviewed and discussed in details.

Factors predicting development of post-thrombotic syndrome in patients with a first episode of deep vein thrombosis: preliminary report

OBJECTIVE

To investigate the indicative parameters reflecting the progression of post-thrombotic syndrome (PTS) in patients with a first episode of deep vein thrombosis (DVT).

DESIGN AND METHODS

The patients' initial risk factors were assessed at presentation. Venous occlusion, and reflux and reflux parameters were evaluated at 6 months using venous duplex scanning. Near-infrared spectroscopy (NIRS) was also used to measure calf muscle deoxygenated haemoglobin levels at 6 months. Clinical manifestations were categorised using the clinical, etiologic, anatomic and pathophysiologic (CEAP) classification for chronic venous insufficiency (CVI), and the patients were divided into those having no PTS (C(0-3S),E(s),A(s,d,p),P(r,o)) and those having PTS (C(4-6S),E(s),A(s,d,p),P(r,o)).

RESULTS

Of the 121 patients evaluated, 25 (21%) developed PTS with a mean follow-up period of 66 months. At initial presentation, ilio-femoral DVT (odds ratio (OR) 3.4, 95% confidence interval (CI) 1.4-8.6) was associated with development of PTS. At 6 months, venous occlusion combined with reflux (OR 4.4, 95% CI 2.9-20.7), peak reflux velocity >29.7 cm s(-1) (OR 13.7, 95% CI 4.1-45.7) and mean reflux velocity >8.6 cm s(-1) (OR 4.4, 95% CI 1.5-12.9) in the popliteal vein detected by duplex scanning were strong predictors of PTS. NIRS-derived retention index >3.5 was the strongest predictor of PTS at 6 months (OR 67.4, 95% CI 14.3-318.1).

CONCLUSIONS

Ilio-femoral DVT is associated with the development of PTS at initial presentation. By contrast, occlusion and reflux, high reflux velocity in the popliteal vein and increased NIRS-derived retention index are important time-course predictors of PTS progression.

The postthrombotic syndrome

Following deep vein thrombosis (DVT), one of every two patients will develop postthrombotic syndrome (PTS), which causes remarkable consequences on the socioeconomic level. Residual thrombosis is an important predictor of PTS, and severe early symptoms, old age, obesity, improper anticoagulation, recurrent thrombosis and varicose veins are major risk factors. Diagnosis of PTS is mainly based on the clinical findings for patients with a history of DVT, while in those without it, instrumental diagnosis might help in detecting a previous DVT. Prompt administration of adequate compression elastic stockings (ECS) in patients with symptomatic DVT reduces the frequency of PTS by half. Usually, the management of an established PTS is demanding, and often discouraging. However, when carefully supervised and instructed to wear proper ECS, more than 50% of patients either remain quiescent or improve during long-term follow-up.

Recurrent deep vein thrombosis: long-term incidence and natural history

OBJECTIVE

To determine the long-term incidence, risk factors, and associated morbidity and mortality of recurrent deep vein thrombosis (DVT).

SUMMARY BACKGROUND DATA

Few studies have examined the long-term natural history and impact of recurrent DVT.

METHODS

We conducted a prospective observational study that followed 153 consecutive patients with an acute first episode of DVT. Clinical examination and ultrasound were performed serially for at least 5 years. Location and extent of the initial DVT, recurrence, pulmonary embolism, cause of mortality, signs and symptoms of post thrombotic syndrome (PTS), and the risk factors were recorded.

RESULTS

The incidence of recurrence at 5 years was 26.1%. Patients with both proximal and distal DVT had a higher recurrence rate than proximal (17/48 35% vs. 12/49, 24%, P = 0.27) or calf alone (11/56, 20%, P = 0.08). Unprovoked DVT and age >65 years were associated with higher recurrence rates (P < 0.001; relative risk [RR]: 2.9, 95% confidence interval [CI]: 1.5-5.7) and (P = 0.025; RR: 1.5, 95% CI: 1-2.3), respectively. Thrombophilia was not associated with increased risk of recurrence (P = 0.21). Patients with DVT due to surgery or trauma had a lower recurrence (P < 0.001). Ipsilateral recurrence was associated with increased severity of PTS (P < 0.001; RR: 1.6, 95% CI: 1.4-2.2). PE occurred 47 times, 12 (25%) of which were fatal events.

CONCLUSIONS

Factors associated with a higher rate of recurrence included unprovoked DVT and age >65. Elevated thrombus burden had a trend towards higher risk. Patients with surgery and trauma had low recurrence rates. Ipsilateral recurrence was strongly associated with PTS. PE occurred frequently and was a common cause of death.

How I treat postthrombotic syndrome

Postthrombotic syndrome (PTS) is a chronic complication of deep venous thrombosis (DVT) that reduces quality of life and has important socioeconomic consequences. More than one-third of patients with DVT will develop PTS, and 5% to 10% of patients will develop severe PTS, which may manifest as venous ulceration. The principal risk factors for PTS are persistent leg symptoms 1 month after the acute episode of DVT, extensive DVT, recurrent ipsilateral DVT, obesity, and older age. Daily use of elastic compression stockings (ECSs) for 2 years after proximal DVT appears to reduce the risk of PTS; however, there is uncertainty about optimal duration of use and compression strength of ECSs and the magnitude of their effect. The cornerstone of managing PTS is compression therapy, primarily using ECSs. Venoactive medications such as aescin and rutoside may provide short-term relief of PTS symptoms. The likelihood of developing PTS after DVT should be discussed with patients, and symptoms and signs of PTS should be monitored during clinical follow-up. Further studies to elucidate the pathophysiology of PTS, to identify clinical and biologic risk factors, and to test new preventive and therapeutic approaches to PTS are needed to ultimately improve the long-term prognosis of patients with DVT.