Postthrombotic Syndrome in Patients Treated With Rivaroxaban or Warfarin for Venous Thromboembolism

Acute phase determinant of post-thrombotic syndrome: A review of the literature

BACKGROUND

Post-thrombotic syndrome (PTS) is the main long-term complication of deep vein thrombosis (DVT). Several therapies are being evaluated to prevent or to treat PTS. Identifying the patients most likely to benefit from these therapies presents a significant challenge.

OBJECTIVES

The objective of this review was to identify risk factors for PTS during the acute phase of DVT.

ELIGIBILITY CRITERIA

We searched the PubMed and Cochrane databases for studies published between January 2000 and January 2021, including randomized clinical trials, meta-analyses, systematic reviews and observational studies.

RESULTS

Risk factors for PTS such as proximal location of DVT, obesity, chronic venous disease, history of DVT are associated with higher risk of PTS. On the initial ultrasound-Doppler, a high thrombotic burden appears to be a predictor of PTS. Among the evaluated biomarkers, some inflammatory markers such as ICAM-1, MMP-1 and MMP-8 appear to be associated with a higher risk of developing PTS. Coagulation disorders are not associated with risk of developing PTS. Role of endothelial biomarkers in predicting PTS has been poorly explored. Lastly, vitamin K antagonist was associated with a higher risk of developing PTS when compared to direct oral anticoagulants and low molecular weight heparin.

CONCLUSIONS

Several risk factors during the acute phase of VTE are associated with an increased risk of developing PTS. There is a high-unmet medical need to identify potential biomarkers for early detection of patients at risk of developing PTS after VTE. Inflammatory and endothelial biomarkers should be explored in larger prospective studies to identify populations that could benefit from new therapies.

Current challenges in the prevention and management of post-thrombotic syndrome-towards improved prevention

Post-thrombotic syndrome (PTS) is a common and potentially debilitating complication of deep vein thrombosis (DVT), affecting up to 50% of DVT patients. The consequence of this chronic condition includes reduced quality of life, increased use of the healthcare system and decreased productivity. The societal impact of this condition is projected to increase, given our ageing population and increased burden of thrombotic diseases. Despite significant recent advances in our understanding of PTS, many unanswered questions remain. Currently, there are few effective and proven options for established PTS; hence, the emphasis should be on instituting effective prevention to reduce the progression to PTS. Effective anticoagulation lowers the risk of PTS, with direct oral anticoagulants appearing to outperform vitamin-K antagonists. However, the evidence for elastic compression stockings and endovascular thrombolysis or thrombectomy techniques remains unclear. Accurate identification of individuals at high risk of developing PTS may also improve the targeting of preventative interventions. This review will examine the current body of evidence regarding PTS, with a focus on preventative strategies as well as novel biomarkers.

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.

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.

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.

Risk Factors for Post-Thrombotic Syndrome in Patients With a First Proximal Deep Venous Thrombosis Treated With Direct Oral Anticoagulants

The incidence of post-thrombotic syndrome (PTS) in patients with deep vein thrombosis (DVT) treated with direct oral anticoagulants (DOACs) remains a matter of debate. Hence, our endeavor to investigate a large cohort of patients with a first episode of proximal DVT treated with DOACs to ascertain the incidence and predisposing risk factors for PTS. All consecutive patients referred to the Thrombotic and Haemorrhagic Diseases Unit of Padova University Hospital (Italy) between January 2014 and January 2018 for a first episode of proximal DVT were considered for enrollment. Participants received DOACs for a minimum period of 3 months. PTS was assessed using the Villalta score up to 36 months after DVT diagnosis. Among 769 enrolled patients (M/F 353/416, age range 26–87 years), 152 (19.8%) developed PTS and 30 (3.9%) developed severe PTS. The adjusted hazard ratio was significant for obesity (1.64, 95% CI 1.28–2.39) and DVT site (femoral and/or iliac veins vs popliteal vein) (1.23, 95% CI 1.15–3.00). The incidence of PTS is not negligible in patients with proximal DVT despite the use of DOACs. We identified obesity and iliofemoral DVT as possible risk factors for PTS. Larger prospective studies are needed to confirm our findings and optimize therapeutic strategies.

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.

Post-thrombotic syndrome in patients with venous thromboembolism treated with dabigatran or warfarin: A long-term cross-sectional follow-up of RE-COVER study patients

BACKGROUND

Studies suggest that the direct factor Xa inhibitor rivaroxaban compared to warfarin reduces the risk of post-thrombotic syndrome (PTS) after deep vein thrombosis (DVT), but this has not been evaluated for oral direct thrombin inhibitors.

OBJECTIVES

To compare the long-term prevalence of PTS, recurrent venous thromboembolism (VTE), and health-related quality of life (HRQoL) in patients with acute DVT and/or pulmonary embolism (PE), randomized to treatment with dabigatran or warfarin in the phase III RE-COVER studies.

METHODS

We conducted a cross-sectional follow-up study of patients randomized in Canada, Norway, and Sweden. PTS was assessed by the patient-reported Villalta scale (PRV) and HRQoL by EQ-5D and VEINES-QOL/Sym.

RESULTS

We included 349 patients between December 2015 and November 2018; 166 were treated with dabigatran and 183 with warfarin. DVT (+/- PE) was index event in 255 patients, whereas 94 patients had PE only. Mean time from index event was 8.7 (standard deviation 1.4) years. PTS was diagnosed in 63% of patients with DVT and in 46% of patients with PE only, and did not differ between the treatment groups; the crude odds ratio (OR) for PTS in patients treated with dabigatran compared with warfarin was 1.1 (95% confidence interval [CI] 0.6-1.8) after DVT and 1.2 (95% CI 0.5-2.6) after PE only. The prevalence of recurrent VTE was 21% in both treatment groups. HRQoL scores did not differ between groups.

CONCLUSION

In this long-term cross-sectional study, the prevalence of PTS, recurrent VTE, and HRQoL were similar in patients treated with dabigatran and warfarin.

Efficacy of rivaroxaban in prevention of post-thrombotic syndrome: a systematic review and meta-analysis

OBJECTIVE

Direct oral anticoagulants (DOACs) have been recommended for the treatment of deep vein thrombosis (DVT). However, the benefits are uncertain for the prevention of post-thrombotic syndrome (PTS). We performed a systematic review and meta-analysis of reported studies to assess the efficacy of DOACs vs vitamin K antagonists for the risk reduction of PTS in patients with DVT.

METHODS

We searched PubMed, Medline, the Cochrane Library, Embase, and the Web of Science for studies reporting on the development of PTS after acute DVT. The outcomes were the risk reduction of PTS, PTS severity, the presence of residual vein thrombosis, and the incidence of recurrent venous thromboembolic (VTE) events.

RESULTS

A total of 59,199 patients from six retrospective and two randomized controlled studies had received DOAC treatment and were followed up for the development of PTS. In all studies, rivaroxaban had been compared with initial low-molecular-weight heparin followed by warfarin. Of the 59,199 patients, 19,840 (33.5%) had received rivaroxaban and 39,377 (66.5%), warfarin. The rivaroxaban group had a significant reduction in PTS development compared with the warfarin group (odds ratio [OR], 0.52; 95% confidence interval [CI], 0.43-0.63; P < .001). Severe PTS was less common in the rivaroxaban group than in the warfarin group (3.7% vs 6.4%; OR, 0.55; 95% CI, 0.36-0.85; P = .024). Additionally, rivaroxaban was associated with a significant reduction in VTE recurrence (OR, 0.83; 95% CI, 0.59-1.18; P = .03) and low rates of residual vein thrombosis compared with warfarin (36.5% vs 51.8%; P = .037).

CONCLUSIONS

Rivaroxaban after acute DVT was associated with a reduced risk of PTS compared with warfarin. Patients treated with rivaroxaban more rarely developed severe PTS and recurrent VTE events compared with patients treated with warfarin.

Comparing Safety and Efficacy of Rivaroxaban with Warfarin for Patients after Successful Stent Placement for Chronic Iliofemoral Occlusion: A Retrospective Single Institution Study

OBJECTIVE

The aim was to compare the safety and effectiveness of rivaroxaban and warfarin as anticoagulants for treating patients with post-thrombotic syndrome (PTS) with chronic iliofemoral venous occlusion undergoing iliofemoral venous stenting.

METHODS

This single institution retrospective study analysed patients with PTS with chronic iliofemoral venous occlusion who were prescribed rivaroxaban or warfarin for one year after successfully undergoing iliofemoral venous stenting. The primary safety and efficacy endpoints were bleeding complication rate and primary patency rate at one year. Secondary outcomes included Villalta score, symptom recurrence rate, ulcer healing rate, and clinically driven target lesion revascularisation (CD-TLR) rate during follow up.

RESULTS

From January 2016 to December 2017, 154 legs from 154 patients were included in this study (69 in rivaroxaban group and 85 in warfarin group). The groups were well matched for patient demographics, clinical characteristics, and procedural details. There was no significant difference between the rivaroxaban group and warfarin group in bleeding complication rate (10% vs. 16%, p = .23, hazard ratio [HR] 0.58, 95% confidence interval [CI] 0.25 - 1.37) at one year, as well as major bleeding complication rate (0% vs. 2%, p = .20, HR 0.16, 95% CI 0.01 - 2.61) and minor bleeding complication rate (10% vs. 14%, p = .40, HR 0.67, 95% CI 0.27 - 1.66). The primary patency rate was higher in the rivaroxaban group at one year (84% vs. 71%, p = .049, HR 0.50, 95% CI 0.26 - 0.96) and at two years (79% vs. 63%, p = .037, HR 0.52, 95% CI 0.29 - 0.93). At a mean follow up of 24 months (range 1 - 42 months), the rivaroxaban group had a significantly lower post-operative Villalta score (4.87 ± 3.51 vs. 6.88 ± 5.85, p = .010, t = 2.64, 95% CI 0.50 - 3.52), lower rate of symptom recurrence (4% vs. 32%, p < .001), lower CD-TLR rates (3% vs. 13%, p = .039), and higher ulcer healing rate (90% vs. 59%, p = .004) than the warfarin group.

CONCLUSION

For PTS patients with chronic iliofemoral venous occlusion undergoing iliofemoral venous stenting, rivaroxaban probably exhibited similar safety but superior efficacy to warfarin. However, further prospective control studies with large sample size are necessary to confirm the results.

The risk of post-thrombotic syndrome in patients with proximal deep vein thrombosis treated with the direct oral anticoagulants

The novel direct oral anticoagulants (DOAC) have been shown to be at least as effective as and safer than conventional anticoagulants for the initial and long-term treatment of venous thromboembolic disorders. However, the rate of post-thrombotic syndrome (PTS) in patients with deep-vein thrombosis (DVT) treated with the DOACs is unknown. With the adoption of the Villalta scale, we assessed the rate of PTS at the end of the follow-up period in a consecutive series of 309 outpatients with acute proximal DVT who had received at least 3 months of treatment with a DOAC and had been followed-up for up to 3 years. The rate of PTS development was compared with that recorded in a historical cohort of 1036 consecutive patients who had been treated with vitamin K antagonists (VKA) and had received a similar follow-up examination. Logistic regression analysis, including propensity scoring to adjust for differing probabilities of undergoing VKA/DOAC, was used to identify predictors of PTS. PTS developed in 87 patients (28.2%) treated with the DOACs (severe in 12), and in 443 patients (42.8%) treated with VKAs (severe in 61). After adjusting for estimated propensity score, age, gender, concomitant symptoms of pulmonary embolism, duration of anticoagulation and development of residual vein thrombosis, the risk of PTS in the DOAC-treated patients was reduced by 54% in comparison to patients treated with conventional anticoagulation (odds ratio 0.46; 95% CI 0.33 to 0.63). We conclude that in comparison to VKAs, the use of the direct oral anticoagulants has the potential to offer a more favorable prognosis in terms of PTS development.

Cessation of anticoagulation therapy following endovascular thrombus removal and stent placement for acute iliofemoral deep vein thrombosis

Summary. Background: The optimal duration of anticoagulation therapy (AT) following catheter-based therapy of acute iliofemoral deep vein thrombosis (IFDVT) with stent placement is unknown. Theoretically, resolving the underlying obstructive iliac vein lesion by a stent may eliminate the main trigger for recurrence, the post-thrombotic syndrome (PTS), and the need for extended-duration AT. Patients and methods: From 113 patients with acute IFDVT who underwent endovascular thrombus removal and stent placement, we compared patency rates and clinical outcomes between 58 patients on limited-duration AT (3–12 month) and 55 patients on extended-duration AT (> 12 months). Results: Mean follow-up duration was 26 ± 18 (range 3–77) months; it was 24 ± 18 (range 3–69) months after cessation of AT in the limited-duration AT group. In comparison to patients with extended-duration AT, patients with limited-duration AT were younger (38 versus 54 years; p < 0.001), more often female (74 % versus 49 %; p = 0.01), and had less often prior venous thromboembolism (VTE) (9 % versus 35 %; p = 0.001). May-Thurner syndrome was more frequent in the limited-duration AT group (66 % versus 38 %; p = 0.004). Overall, primary and secondary patency rates at 24 months were 80 % (95 % CI, 70–87 %) and 95 % (95 % CI, 88–98 %), respectively, with no difference between the groups. Overall, 17 (15 %) patients developed recurrent VTE, of which 14 (82 %) events were thrombotic stent occlusions, and 13 (76 %) events occurred during AT. In the limited-duration AT group, 98 % patients were free from the PTS at two years with a VTE recurrence rate of 3.5 per 100 patient years after cessation of AT. Conclusions: In selected patients with acute IFDVT and patent venous stent, particularly in younger and otherwise healthy patients with May-Thurner syndrome, it appears to be safe to discontinue AT 3–12 months after endovascular treatment. Clinical Trial Registration: The study is registered on the National Institutes of Health website (ClinicalTrials.gov; identifier NCT02433054).