Recanalization rate in patients with proximal vein thrombosis treated with the direct oral anticoagulants

A retrospective assessment of venous recanalization outcomes for oral anticoagulant treatment in deep vein thrombosis

OBJECTIVE

This study aims to provide effective treatment by comparing the venous recanalization responses of oral anticoagulants in deep vein thrombosis therapy.

METHODS

From January 2013 to March 2019, a retrospective analysis was conducted on 109 patients who had been diagnosed with deep vein thrombosis and received treatment with apixaban, rivaroxaban, or warfarin within 1 week of symptom onset. Demographic, clinical data, and venous recanalization responses on Doppler ultrasonography of the patients that were followed-up 1 year from the date of diagnosis were evaluated.

RESULTS

At the end of the 1-year follow-up, 21 (19.3%) patients had delayed recanalization, 39 (35.8%) patients had partial recanalization, and 49 (44.9%) patients had complete recanalization. The mean time to complete recanalization was 9.178 months for apixaban, 8.986 months for rivaroxaban, and 10.641 months for warfarin. Rivaroxaban was found to result in earlier completion of recanalization compared to warfarin (p = .012).

CONCLUSION

Direct oral anticoagulants might be more effective than vitamin K antagonists in achieving complete recanalization in patients that have deep vein thrombosis. Improving outcomes can be achieved by evaluating current treatment options.

Post-thrombotic syndrome and chronic thromboembolic pulmonary hypertension: diagnosis and management

Post-thrombotic syndrome and chronic thromboembolic pulmonary hypertension are two distinct clinical syndromes associated with adverse patient outcomes following a venous thromboembolism. Clinical manifestations of post-thrombotic syndrome include persistent pain, swelling and ultimately venous ulceration following a deep venous thrombosis. Patients experiencing chronic thromboembolic pulmonary hypertension may have symptoms ranging from exertional dyspnoea to overt right heart failure. From a physician's perspective, the most effective preventative strategy is good quality anticoagulation for prophylaxis of primary and secondary venous thromboembolism. The treatment of post-thrombotic syndrome mainly involves lifestyle modifications alongside the use of elastic compression stockings while patients with chronic thromboembolic pulmonary hypertension should be offered targeted surgical and medical treatment options available at expert centres. Further research is warranted for both conditions to determine the role of direct oral anticoagulants when used with a preventive or therapeutic intent.

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.

[Risk of post-thrombotic syndrome following direct oral anticoagulant intake: a systematic review and meta-analysis]

OBJECTIVE

To perform a systematic review and meta-analysis of data devoted to the risk of post-thrombotic syndrome (PTS) following direct oral anticoagulant (DOAC) intake.

MATERIAL AND METHODS

A systematic review and meta-analysis of trials available in the PubMed database were performed in March 2021. Analysis included the reports with known Villalta score for PTS in patients receiving DOACs or alternative anticoagulation. We analyzed the incidence and risk of any form of PTS.

RESULTS

We found 10 comparative studies comprising 3161 patients. Incidence of PTS under DOAC therapy was 30.8% (95% confidence interval (CI) 22.2-39.3%), severe PTS - 2.2% (95% CI 1.0-3.4%). DOACs were associated with significantly less risk of any form of PTS (odds ratio (OR) 0.57; 95% CI 0.48-0.68; p<0.001) and severe PTS (OR 0.56; 95% CI 0.36-0.87; p=0.010) compared to vitamin K antagonists. Among various DOACs, specified data were available only for rivaroxaban (OR 0.54, 95% CI 0.42-0.71, p<0.001 for any PTS; OR 0.49, 95% CI 0.27-0.89, p=0.019 for severe PTS). The use of flavonoids in adjunction to rivaroxaban was associated with additional risk reduction for PTS (OR 0.14; 95% CI 0.06-0.31; p<0.001).

CONCLUSION

Moderate quality evidence suggests that DOACs are associated with significant less risk of any PTS and severe PTS compared to VKA in patients with deep vein thrombosis. Among all DOACs, only rivaroxaban has clear data confirming PTS risk reduction. The use of flavonoids in adjunction to rivaroxaban can further improve treatment outcomes.

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.

ERS statement on chronic thromboembolic pulmonary hypertension

Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare complication of acute pulmonary embolism, either symptomatic or not. The occlusion of proximal pulmonary arteries by fibrotic intravascular material, in combination with a secondary microvasculopathy of vessels <500 µm, leads to increased pulmonary vascular resistance and progressive right heart failure. The mechanism responsible for the transformation of red clots into fibrotic material remnants has not yet been elucidated. In patients with pulmonary hypertension, the diagnosis is suspected when a ventilation/perfusion lung scan shows mismatched perfusion defects, and confirmed by right heart catheterisation and vascular imaging. Today, in addition to lifelong anticoagulation, treatment modalities include surgery, angioplasty and medical treatment according to the localisation and characteristics of the lesions.This statement outlines a review of the literature and current practice concerning diagnosis and management of CTEPH. It covers the definitions, diagnosis, epidemiology, follow-up after acute pulmonary embolism, pathophysiology, treatment by pulmonary endarterectomy, balloon pulmonary angioplasty, drugs and their combination, rehabilitation and new lines of research in CTEPH.It represents the first collaboration of the European Respiratory Society, the International CTEPH Association and the European Reference Network-Lung in the pulmonary hypertension domain. The statement summarises current knowledge, but does not make formal recommendations for clinical practice.

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.

Post-thrombotic syndrome

Post-thrombotic syndrome (PTS) is a chronic venous insufficiency manifestation following an episode of deep-vein thrombosis (DVT). It is an important and frequent long-term adverse event of proximal DVT affecting 20-50% of patients. This position paper integrates data guiding clinicians in deciding PTS diagnosis, treatment and follow-up.

Direct Oral Anticoagulants in Patients With Inherited Thrombophilia and Venous Thromboembolism: A Prospective Cohort Study

Background

In this prospective cohort study, we aimed to evaluate the efficacy and safety of direct oral anticoagulants (DOACs) versus heparin/vitamin K antagonists for the treatment of venous thromboembolism (VTE) in patients with inherited thrombophilia.

Methods and Results

We enrolled consecutive patients with acute VTE and inherited thrombophilia treated with DOACs (cases) or heparin/vitamin K antagonists (controls), matched for age, sex, ethnicity, and thrombophilia type. End points were VTE recurrence and bleeding complications; residual vein thrombosis and post‐thrombotic syndrome; VTE recurrence after anticoagulant discontinuation. Two hundred fifty‐five cases (age 52.4±17.3 years, Female 44.3%, severe thrombophilia 33.1%) and 322 controls (age 49.7±18.1 years, Female 50.3%, severe thrombophilia 35.1%) were included. The cumulative incidence of VTE recurrence during anticoagulation was 1.09% in cases versus 1.83%, adjusted hazard ratio (HR) 0.67 (95% CI, 0.16–2.77). The cumulative incidence of bleeding was 10.2% in cases versus 4.97%, HR 2.24 (95% CI 1.10–4.58). No major bleedings occurred in cases (versus 3 in controls). No significant differences regarding residual vein thrombosis and post‐thrombotic syndrome. After anticoagulant discontinuation, DOACs yielded a significantly lower 2‐year VTE recurrence risk versus traditional anticoagulants (HR, 0.61 [95% CI, 0.47–0.82]).

Conclusions

DOACs and heparin/vitamin K antagonists showed a similar efficacy in treating VTE in patients with thrombophilia. Although major bleeding episodes were recorded solely with heparin/vitamin K antagonists, we noted an overall increased bleeding rate with DOACs. The use of DOACs was associated with a lower 2‐year risk of VTE recurrence after anticoagulant discontinuation.

Quality of anticoagulant therapy and the incidence of in-stent thrombosis after venous stenting

BACKGROUND

In patients with a venous outflow obstruction following iliofemoral deep vein thrombosis stenting of the venous tract to prevent or alleviate postthrombotic syndrome is applied with increasing frequency. The impact of the quality of anticoagulant therapy with vitamin K antagonists (VKAs) on the development of in-stent thrombosis is currently unknown.

OBJECTIVES

To determine the association between the quality of postinterventional VKA treatment and the occurrence of in-stent thrombosis.

METHODS

Seventy-nine patients with iliofemoral and/or caval venous stent placement for obstruction of the venous outflow were included in this study. All patients received postinterventional VKA. The quality of VKA anticoagulant therapy was expressed as the time within therapeutic range (TTR) calculated using the linear interpolation method and as the proportion of International Normalized Ratio (INR) values < 2.0. In-stent thrombosis was assessed by the use of duplex ultrasound. Survival analysis (Kaplan-Meier curves, Cox regression) was used to analyze the data.

RESULTS

In-stent thrombosis developed in 16 patients (20.3%). The total population had a mean TTR of 64.0% (±19.0) and a mean proportion of INR values < 2.0 of 11.6% (±12.0). Overall, a TTR < 49.9% was associated with an increased risk of in-stent thrombosis. The multivariable adjusted analysis showed a hazard ratio (HR) of 0.96 (95% confidence interval [CI], 0.92-0.99; P = .02) per 1% increase in TTR. The proportion of INR values < 2.0 had no significant association with the occurrence of in-stent thrombosis: HR 0.98 (95% CI, 0.91-1.06; P = .66).

CONCLUSIONS

We conclude that the quality of anticoagulant treatment reflected in the TTR following a venous stenting procedure is an important independent determinant for the risk of in-stent thrombosis. The role of anticoagulant treatment for the prevention of in-stent thrombosis following stenting procedures therefore merits further research.

Diosmin 600 in adjunction to rivaroxaban reduces the risk of post-thrombotic syndrome after femoropopliteal deep vein thrombosis: results of the RIDILOTT DVT study

BACKGROUND

To assess the efficacy and safety of long-term diosmin 600 therapy added to rivaroxaban and elastic compression stockings (ECS) in patients with femoropopliteal deep vein thrombosis (DVT).

METHODS

This single-center, open-label randomized clinical trial RIDILOTT DVT enrolled patients with their first femoropopliteal DVT confirmed by duplex ultrasound scan (DUS). Participants were randomly allocated to the control group (standard treatment with rivaroxaban for six months and ECS for 12 months) or the experimental group (standard treatment with the additional use of diosmin 600 mg once daily for 12 months). Patients were followed for 12 months. The primary outcome was post-thrombotic syndrome (PTS), according to the Villalta Score (≥5). The secondary outcomes were deep vein recanalization, chronic venous disease (CVD) progression, the severity of PTS (Villalta), and CVD (VCSS), quality of life (CIVIQ-20), venous thromboembolism recurrence, and adverse event (AE).

RESULTS

Ninety patients were randomized (45 per group). There were 56 men and 34 women with a mean age of 57.8±13.4 years, and 69% had clinically unprovoked DVT. PTS frequency at 12 months was significantly lower (8.9% vs. 48.9%) in the experimental group compared with control one (relative risk, 0.14; 95% confidential interval, 0.04-0.43, P<0.001). Adding diosmin 600 was associated with quicker and complete vein recanalization, lower CVD progression rate, and lower Villalta, VCSS, and CIVIQ-20 scores. There was no difference in recurrent DVT or AE.

CONCLUSIONS

Adjunctive use of diosmin 600 to rivaroxaban and ECS in patients with femoropopliteal DVT can improve the clinical and ultrasound outcomes after 12 months of treatment.

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.

Use of Micronized Purified Flavonoid Fraction Together with Rivaroxaban Improves Clinical and Ultrasound Outcomes in Femoropopliteal Venous Thrombosis: Results of a Pilot Clinical Trial

Introduction

The aim of this study was to assess the impact of adding long-term micronized purified flavonoid fraction (MPFF) to standard treatment of femoropopliteal deep vein thrombosis (DVT).

Methods

This pilot, comparative, open-label study with blinded outcome assessor enrolled patients with a first episode of femoropopliteal DVT confirmed by duplex ultrasound scanning (DUS). All participants were randomly allocated to one of two treatment groups: (1) control that received a standard treatment with oral rivaroxaban, and (2) experimental that involved additional treatment with MPFF 1000 mg/day. Both drugs were used for 6 months. Patients were followed for the whole treatment period and underwent DUS every 2 months to determine the degree of recanalization by popliteal (PV), femoral vein (FV), and common femoral vein (CFV) compressibility. Thrombi extension were assessed by the modified Marder score. At the end of the follow-up period, patients were assessed with Villalta and venous clinical severity scales (VCSS). Patients with a Villalta score ≥ 5 were diagnosed with post-thrombotic syndrome (PTS).

Results

Sixty patients were randomized to the control or MPFF groups (n = 30 in each group). There were 40 men and 20 women with a mean age ± SD of 56.3 ± 13.4 years. Clinically unprovoked DVT was recognized in 65% of cases and left side localization in 45%. The mean baseline Marder score was 15.0 ± 4.8 and 11.1 ± 4.3 in the experimental and control groups, respectively (p = 0.002). At 6 months, the mean Villalta score in the MPFF group was significantly lower compared with control (2.9 ± 2.7 versus 5.8 ± 3.0; p < 0.0001). PTS was diagnosed in six patients (20%) and 17 patients (57%) in the experimental and control groups respectively (p = 0.007). A significant difference between the groups was also observed for the VCSS value (2.3 ± 1.9 versus 4.9 ± 1.9; p < 0001). After 6 months of treatment the Marder score decreased to 0.8 ± 1.6 and 2.8 ± 3.5 in the experimental and control groups, respectively (p = 0.006). In the MPFF group, there was a greater reduction in the Marder score (p < 0.0001) and more rapid rate of recanalization for the FV (p < 0.0001), with a non-significant trend for the CFV (p = 0.130) and PV (p = 0.204) compared with the control group. Full recanalization of the PV at 6 months was observed in 24 patients (80%) who had received MPFF, and only 17 patients (57%) in the control group (p = 0.095).

Conclusion

The addition of MPFF to standard therapy for DVT in the form of oral rivaroxaban can reduce the incidence of PTS at 6 months in patients with proximal DVT and increase the speed of deep vein recanalization.

Funding

Les Laboratoires Servier funded the article processing fees, editorial assistance, and open access fee for this manuscript.

Ultrasound elastography is useful to distinguish acute and chronic deep vein thrombosis

Essentials Ultrasound elastography uses tissue deformation to assess the relative quantification of its elasticity. Compression and duplex ultrasonography may be unable to correctly determine the thrombus age. Ultrasound elastography may be useful to distinguish between acute and chronic deep vein thrombosis. The exact determination of the thrombus age could have both therapeutic and prognostic implications. BACKGROUND: Background Ultrasound elastography (UE) imaging is a novel sonographic technique that is commonly employed for relative quantification of tissue elasticity. Its applicability to venous thromboembolic events has not yet been fully established; in particular, it is unclear whether this technique may be useful in determining the age of deep vein thrombosis (DVT). Thus, the aim of this study was to assess the role of UE in distinguishing acute from chronic DVT. Methods Consecutive patients with a first unprovoked acute and chronic (3 months old) DVT of the lower limbs were analyzed. Patients with recurrent DVT or with a suspected recurrence were excluded. The mean elasticity index (EI) values of acute and chronic popliteal and femoral vein thrombosis were compared. The accuracy of the EI in distinguishing acute from chronic DVT was also assessed by measuring the sensitivity, specificity, positive and negative predictive values, and likelihood ratios. Results One-hundred and forty-nine patients (mean age 63.9 years, standard deviation 13.6; 73 males) with acute and chronic DVT were included. The mean EI of acute femoral DVT was higher than that of chronic femoral DVT (5.09 versus 2.46), and the mean EI of acute popliteal DVT was higher than that of chronic popliteal DVT (4.96 versus 2.48). An EI value of > 4 resulted in a sensitivity of 98.9% (95% confidence interval [CI] 93.3-99.9), a specificity of 99.1% (95% CI 94.8-99.9), a positive predictive value of 91.1% (95% CI 77.9-97.1), a negative predictive value of 98.6% (95% CI 91.3-99.9), a positive likelihood ratio of 13.23 (95% CI 93-653) and a negative likelihood ratio of 0.001 (95% CI 0.008-0.05) for acute DVT. Conclusions UE appears to be a promising technique for distinguishing between acute and chronic DVT. Larger prospective studies are warranted to confirm our preliminary findings.

What have we learned from real-world NOAC studies in venous thromboembolism treatment?

Venous thromboembolism (VTE) remains a substantial clinical and health-economic burden worldwide and effective anticoagulant treatment is necessary immediately after VTE is suspected to reduce short- and long-term VTE related morbidity and mortality. For decades, low molecular weight heparin (LMWH), fondaparinux and Vitamin K antagonists (VKAs) have been the standard of anticoagulant therapy for VTE patients but these treatment options had clinically relevant drawbacks and limitations. The introduction of non-VKA oral anticoagulants (NOACs) that specifically inhibit either thrombin or factor Xa have resolved many of these drawbacks because these new compounds exhibit a rapid onset and offset of action, fewer food and drug interactions and a predictable anticoagulant effect. All NOACs have successfully completed their respective phase-III trial programs consisting of many large randomized controlled trials, leading to approval for acute VTE treatment around the world. Nevertheless, their introduction into daily care practice is challenging and a careful evaluation of the effectiveness and safety of NOACs in less selected cohorts outside carefully monitored clinical trials is essential. This review introduces the different types of real-world evidence (RWE) and explores the available data for VTE treatment with NOACs, based on a literature search using the key words "venous thromboembolism" or "VTE" in combination with "NOAC", "DOAC", "apixaban", "dabigatran", "edoxaban" and "rivaroxaban" on June 30; 2017, followed by data extraction from studies that reported real-world outcome data for VTE treatment with NOACs, although available evidence is almost exclusively limited to rivaroxaban.