Anticoagulants for the treatment of isolated lower limb superficial vein thrombosis a Bayesian network meta-analysis of randomized controlled trials

OBJECTIVE

Assess the safety and efficacy of anticoagulants in treating isolated superficial vein thrombosis (iSVT).

MATERIALS AND METHODS

A systematic review was conducted according to PRISMA 2020 guidelines, for randomized controlled trials (RCTs) investigating anticoagulants in the treatment of iSVT. The primary endpoint of thrombotic complications encompassed any incident of iSVT progression/recurrence and the development of new-onset (deep vein thrombosis) DVT or (pulmonary embolism) PE.

RESULTS

Eight RCT's and 4721 patients treated once daily with either fondaparinux 2.5 mg, rivaroxaban 10 mg, therapeutic, intermediate, and prophylactic low molecular weight heparin (LMW) were included. While all anticoagulants displayed a statistically significant risk reduction compared to placebo in terms of thrombotic complications and iSVT progression/recurrence, only fondaparinux reduced the risk for DVT/PE. Additionally, fondaparinux exhibited enhanced efficacy in decreasing DVT/PE events relative to prophylactic and therapeutic LMWH. Furthermore, rivaroxaban and fondaparinux demonstrated superior outcomes in terms of preventing thrombotic complications compared to all three dosing regimens of LMWH without significant differences between the two, risk ratio RR 1.00(95%CI:0.51-1.92). SUCRA identified fondaparinux as the most effective treatment regarding thrombotic complications, (SUCRA,91.6) and DVT/PE, (SUCRA,96) and rivaroxaban in terms of iSVT progression/recurrence (SUCRA,94.68). Ultimately and despite certain model limitations, meta-regression analysis suggested a possible trend towards improved outcomes with longer treatment durations for thrombotic complications β = -0.34(95%CI:-16.39to12.23).

CONCLUSIONS

Despite inherent limitations such as variations in treatment durations and follow-up periods, this review displayed the efficacy of fondaparinux, rivaroxaban and LMWH in treating iSVT. The improved efficacy of fondaparinux over therapeutic LMWH in terms of DVT/PE outcomes necessitates cautious interpretation underscoring the need for further investigation through adequately powered RCTs.

A systematic review and meta-analysis for the association between duration of anticoagulation therapy and the risk of venous thromboembolism in patients with lower limb superficial venous thrombosis

OBJECTIVE

The aim of this study was to determine the association between the duration of systemic anticoagulation therapy (ACT) and the risk of further venous thromboembolism (VTE) in patients with superficial venous thrombosis (SVT).

METHODS

A systematic review and meta-analysis were performed using searches of Medline and Cochrane Library databases in September 2023. Papers that provided VTE incidence within mid-term follow-up of ≥45 days in patients who received any ACT were included. Patients were categorized into subgroups according to the course of treatment: (1) no ACT (0 days); (2) ACT of ≤14 days; (3) ACT of 15 to 30 days; (4) ACT of 31 to 45 days; and (5) ACT of >45 days. Reported events were transformed to events per 100 patient-years, and a random-effects model was used to calculate pooled rates for proportions. The primary outcome (VTE) was a combination of SVT progression or recurrence with the occurrence of deep vein thrombosis (DVT) and pulmonary embolism (PE). Secondary outcomes included major and clinically relevant non-major or minor bleeding.

RESULTS

Twenty-four studies (10 randomized controlled trials and 14 cohort studies) combining outcomes in 12,341 patients were included in the quantitative synthesis. Minimum VTE and SVT recurrence or progression rates were observed with the ACT duration of 31 to 45 days of 16.2 (95% confidence interval [CI], 10.4-23.3) and 8.2 (95% CI, 3.1-15.8) events per 100 patient-years, respectively. Minimum DVT and PE rates observed with the treatment duration of 15 to 30 days were 5.5 (95% CI, 2.8-9.1) and 0.9 (95% CI, 0.5-1.3) events per 100 patient-years, respectively. Short-term treatment of ≤14 days was associated with the highest rates of VTE of 59.7 (95% CI, 37.7-86.4), DVT of 13.7 (95% CI, 9.6-18.4), and PE of 3.1 (95% CI, 1.4-5.6) events per 100 patient-years. Major bleeding rates were unrelated to the duration of ACT and did not exceed 0.5 events per 100 patient-years. The highest rate of clinically relevant non-major or minor bleeding was observed with ACT duration of 31 to 45 days of 14.2 (95% CI, 5.5-26.8) events per 100 patient-years. The most common risk factors for VTE included male sex, cancer, personal history of DVT, PE, or SVT, and thrombosis of non-varicose veins.

CONCLUSIONS

Prolonged systemic anticoagulation is associated with the tendency to decrease VTE rates in patients with lower limb SVT.

Three-Month Outcomes in Cancer Patients with Superficial or Deep Vein Thrombosis in the Lower Limbs: Results from the RIETE Registry

Background: The clinical characteristics and outcomes of cancer patients with lower-limb isolated superficial vein thrombosis (SVT) have not been consistently evaluated. Methods: We used data in the RIETE registry to compare the clinical characteristics and 90-day outcomes for patients with: (1) active cancer and lower-limb SVT; (2) active cancer and lower-limb deep vein thrombosis (DVT); (3) lower-limb SVT without cancer. The primary outcomes included subsequent symptomatic SVT, DVT or pulmonary embolism (PE). Secondary outcomes were major bleeding and death. Results: From March 2015 to April 2021, there were 110 patients with cancer and SVT, 1695 with cancer and DVT, and 1030 with SVT but no cancer. Most patients in all subgroups (93%, 99% and 96%, respectively) received anticoagulants, while those with SVT received lower daily doses of low-molecular-weight heparin (114 ± 58, 163 ± 44, and 106 ± 50 IU/kg, respectively). During the first 90 days, 101 patients (3.6%) developed subsequent VTE (PE 47, DVT 41, SVT 13), whereas 72 (2.5%) had major bleeding and 282 (9.9%) died. Among the three groups, 90-day events were, respectively: VTE at rates of 7.3%, 4.0% and 2.4%; major bleeding at rates of 2.7%, 3.9% and 0.3%; mortality at rates of 8.2%, 16% and 0.3%. Between D90 and D180, only one SVT recurrence and one death occurred in SVT cancer patients. In multivariable analysis, cancer was associated with subsequent VTE (HR = 2.04; 1.15–3.62), while initial presentation as SVT or DVT were not associated with a different risk. Conclusions: The risk for subsequent VTE (including symptomatic SVT, DVT or PE) was similar in cancer patients with isolated SVT than in those with isolated DVT.

Position Paper on the Management of Pregnancy-Associated Superficial Venous Thrombosis. Balkan Working Group for Prevention and Treatment of Venous Thromboembolism

Venous thromboembolism (VTE) is a multifactorial disease that can possibly affect any part of venous circulation. The risk of VTE increases by about 2 fold in pregnant women and VTE is one of the major causes of maternal morbidity and mortality. For decades superficial vein thrombosis (SVT) has been considered as benign, self-limiting condition, primarily local event consequently being out of scope of well conducted epidemiological and clinical studies. Recently, the approach on SVT has significantly changed considering that prevalence of lower limb SVT is twice higher than both deep vein thrombosis (DVT) and pulmonary embolism (PE). The clinical severity of SVT largely depends on the localization of thrombosis, when it concerns the major superficial vein vessels of the lower limb and particularly the great saphenous vein. If untreated or inadequately treated, SVT can potentially cause DVT or PE. The purpose of this review is to discuss the complex interconnection between SVT and risk factors in pregnancy and to provide evidence-based considerations, suggestions, and recommendations for the diagnosis and treatment of this precarious and delicate clinical entity.

Oberflächliche Venenthrombose der Beinvenen – Eine systematische Übersicht – Teil 2: Therapie

Einleitung Die oberflächliche Venenthrombose (OVT) der Beinvenen ist mit einer Inzidenz von 0,5–1/1000 Einwohner/Jahr ein häufiges und mit einer Frequenz assoziierter thromboembolischer Ereignisse in bis zu 25 % der Fälle ein ernst zu nehmendes Krankheitsbild. In der vorliegenden Übersichtsarbeit sollen alle relevanten Aspekte der OVT basierend auf der aktuellen wissenschaftlichen Literatur behandelt werden.

Methoden Die systematische Übersicht umfasst das Wissen über die OVT basierend auf dem gesamten, systemisch recherchierten Erkenntnismaterial in den Datenbanken PubMed und Google Scholar. Eine Literaturrecherche in PubMed von Publikationen (1968–2018) mit den Suchbegriffen „Superficial vein thrombosis; thrombophlebitis“ ergab 102 aussagekräftige Arbeiten, die nach Vorlage der Originalarbeit ausgewertet wurden. Teil 2 der Arbeit behandelt Aspekte zur Therapie.

Ergebnisse Die Bewertungskriterien der Therapie der OVT sind in den einzelnen Leitlinien und Übersichtsarbeiten z. T. unterschied­lich. Andererseits ist in den letzten Jahren eine zunehmende Stringenz in den Therapieempfehlungen festzustellen, die vom Ausprägungsgrad der OVT abhängig sind. Zu deren Prinzipien gehören die Mobilisation des Patienten und das Tragen eines medizinischen Kompressionsstrumpfes der Kompressionsklasse II. Die medikamentöse Therapie umfasst den Einsatz von Fondaparinux oder niedermolekularen Heparinen. Fondaparinux ist derzeit das einzig zugelassene Medikament für diese Indikation ab einer Thrombusausdehnung von mindestens 5 cm. Rivaroxaban in einer Tagesdosis von 10 mg war gegenüber Fondaparinux in einer randomisierten Studie nicht unterlegen; dies führte jedoch nicht zu einer Zulassung für die Indikation der OVT. Eine therapeutische Antikoagulation hingegen wird empfohlen, sobald sich das proximale Thrombusende 3 cm oder näher zum Übergang in das tiefe Venensystem befindet. Nichtsteroidale Antirheumatika reduzieren das Risiko einer OVT-Extension oder eines Rezidivs und wirken schmerzlindernd. Die Therapie mit Externa bietet nur lokale symptomlindernde Effekte. Eine operative Therapie der OVT kann in bestimmten Situationen erwogen werden, um Varizen, Schmerzen und das Risiko einer Thrombusaszension in einem Behandlungsschritt zu beseitigen.

Schlussfolgerung Aufgrund der Häufigkeit und des Risikos potenziell lebensbedrohender Komplikationen sollte der OVT der Beinvenen eine größere Beachtung zukommen, insbesondere mit Blick auf eine auf den individuellen Befund ausgerichtete Stadien-adaptierte Therapie.

Temporal and anatomic relationship between superficial and deep vein thromboses in hospitalized children

BACKGROUND

Recent publications have increasingly demonstrated a link between superficial-vein thrombosis (SVT) and deep-vein thrombosis (DVT) in the adult population and have led to changes in SVT treatment considerations. A similar relationship between SVT and DVT in pediatric populations, however, is not currently well established.

OBJECTIVES

We sought to evaluate the temporal and anatomic relationship between SVT and DVT among pediatric inpatients in order to determine to what degree SVT is associated with DVT.

METHODS

We first retrospectively reviewed our institution's local prospective hospital-acquired VTE (HA-VTE) registry to identify all children (age 0-21 years, inclusive) admitted to Children's Hospital Colorado for more than 48 h between January 2012 and September 2017 who developed a DVT while hospitalized. We then reviewed each patient's electronic health record for evidence of SVT to identify SVT + DVT cases. Afterwards, we utilized a list of ICD codes to identify all patients during this time frame who developed an SVT and removed patients whom we previously identified as SVT + DVT cases to obtain the number of patients with isolated SVT.

RESULTS

Of 59,910 patients admitted during the study period, 438 (0.7%) developed a thrombosis while hospitalized - 197 (0.3%) with isolated SVT, 161 (0.3%) with isolated DVT, and 80 (0.1%) with both SVT + DVT. These 80 SVT + DVT patients represent 33% of the 241 total DVT patients and 29% of the 277 total SVT patients. Of the 12 SVT + DVT patients in whom the SVT was diagnosed before the DVT, the subsequent DVT occurred within a mean of 6.4 (range 1-22) days and at the same anatomic site in 6 (50%). The age breakdown for this cohort was: 0 (0%) 0-1 months, 2 (17%) 1 month-2 years, 3 (25%) 2-12 years, 3 (25%) 12-16 years, and 4 (33%) 16-21 years.

CONCLUSIONS

Our results indicate a temporal and anatomic relationship between SVT and DVT in hospitalized children, particularly those with central venous catheters.

Treatment of superficial vein thrombosis with intermediate dose of tinzaparin: A real word cohort study - The SeVEN EXTension study

BACKGROUND

To assess the treatment of superficial vein thrombosis (SVT) with intermediate dose of tinzaparin in a setting of real world practice.

METHODS

Prospective observational study of consecutive patients treated by vascular physicians in the private sector with tinzaparin (131 IU/Kg) once daily. Treatment duration was at the treating physician's discretion. The outcomes of the study were symptomatic venous thromboembolism, extension of thrombus and bleeding complications.

RESULTS

660 patients were included and followed up for at least 3 months. Median duration of treatment was 30 days (14-120). History of prior deep vein thrombosis (HR 2.77; 95% CI= 1.18-6.49; p = 0.018) and current SVT above the knee (HR1.84; 95% CI = 1.33-3.53; p = 0.0002) were associated with prolonged treatment duration. Primary efficacy outcomes occurred in 20 (3%) patients. The median time to the event was 24 (6-92) days and was not related to treatment duration.

CONCLUSIONS

Tinzaparin at intermediate dose is an effective and safe treatment for SVT.

Sonographic evolution of the superficial vein thrombosis of the lower extremity

BACKGROUND

Superficial venous thrombosis (SVT) is a common clinical problem across various treatment settings. SVT shares risk factors with deep venous thrombosis (DVT) and carries a risk of thromboembolic complications, greater than previously expected. Little is known about the pathophysiology, resolution and recurrence of this disease.

OBJECTIVES

The objective of the present study was to describe the natural course of SVT, and factors correlated with the progression or resolution of the thrombus.

METHODS

We included 218 patients with a recent diagnosis of SVT that were consecutively referred to a thrombosis clinic from the Emergency Department (ED) between January 2016 and April of 2018.

RESULTS

The resolution of the thrombus prior to discharge was correlated to gender (female 73.8% vs. male 57.5%, p = 0.015), presence of varicose veins (62.4% vs. 46.4, p = 0.026), absence of family or personal history of thrombosis (98% vs. 91.3%, p = 0.021). The factor most correlated to thrombus resolution prior to discharge was the result of the 2nd ultrasound (improvement 83.9% vs. 16.1%, p < 0.001) immediately after initiation of heparin treatment. In the multivariate analysis, a high thrombus burden in the early follow-up ultrasound was the most significant predictive variable with prior to discharge recanalization (B = 20.9, 95% CI 9.8-44.7; p < 0.001).

CONCLUSION

The follow-up of SVT with duplex lower extremity ultrasound allows us to monitor the evolution and early identify residual thrombosis, as a marker of hypercoagulability and recurrence. This study offers new perspectives for future research, necessary to improve the management of this disease, to reduce long-term complications.

Factors influencing recanalization of thrombotic venous occlusions

Summary. The outcome of a thrombotic vessel occlusion is related to the resolution of thrombus and restitution of blood flow. Thrombus formation simultaneously activates an enzymatic process that mediates endogenous fibrinolysis to maintain vessel patency. The balance between coagulation and fibrinolysis determines the extent of thrombus formation, its resolution, and clinical outcome. Endogenic fibrinolysis is frequently unable to overcome coagulation and to resolve the thrombus. Therefore, for a complete resolution of thrombus in an acute phase, exogenic fibrinolytic agents are needed. Currently, tissue plasminogen activator (tPA) is most frequently used for therapeutic thrombolysis. Also, heparins, particularly low-molecular-weight heparins and direct oral anticoagulants which are known as anticoagulant drugs, have some pro-fibrinolytic properties. Besides the extent and age of a clot, different other factors influence the lysis of thrombus. Thrombus structure is one of the most important determinants of thrombus lysis. The concentration of thrombolytic agent (tPA) around and inside of thrombus importantly determines clot lysis velocity. Further, flow-induced mechanical forces which stimulate the transport of thrombolytic agent into the clot influence thrombolysis. Inflammation most probably represents a basic pathogenetic mechanism of activation of coagulation and influences the activity of the fibrinolytic system. Inflammation increases tissue factor release, platelet activity, fibrinogen concentration and inhibits fibrinolysis by increasing plasminogen activator inhibitor 1. Therefore, recanalization of a thrombotic vessel occlusion is inversely related to levels of some circulating inflammatory agents. Consequently, inhibition of inflammation with anti-inflammatory drugs may improve the efficacy of prevention of thromboembolic events and stimulate recanalization of thrombotic occlusions of veins.

In patients with superficial vein thrombosis the inflammatory response is increased and related to the recanalization rate

INTRODUCTION

Little is known about pathogenetic mechanisms of superficial venous thrombosis (SVT). We aimed to investigate the systemic inflammatory response in the acute phase of SVT, the time course of inflammatory markers and involvement of inflammation in resolution of thrombus in SVT.

MATERIAL AND METHODS

The circulatory inflammatory parameters high-sensitivity C-reactive protein (hsCRP), tumor necrosis factor α (TNF-α), interleukins 6, 8 and 10 (IL-6, IL-8, IL-10), and markers of fibrinolytic activity tissue plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1) and fibrinogen were determined in 68 patients with acute SVT of lower limbs, who were allocated to two groups, dalteparin 5000 IU once daily or 10 000 IU once daily. Recanalization of occluded veins was monitored by ultrasonography at regular intervals. Blood was drawn in the acute phase and after 12 weeks.

RESULTS

In the acute phase a majority of the measured inflammatory markers were increased, while after 12 weeks most of them significantly dropped: hsCRP: 13.6 ±11.9 vs. 7.4 ±4.4, p < 0.001; IL-6: 3.8 ±3.1 vs. 2.6 ±1.9, p = 0.007. Significant changes in endogenic fibrinolytic parameters were also observed: t-PA activity decreased (0.81 ±0.35 vs. 0.68 ±0.34, p = 0.003), while PAI-1 levels increased (5.6 ±5.1 vs. 8.8 ±8.5, p < 0.001). Levels of inflammatory markers at inclusion and after 12 weeks were related to less effective thrombus resolution: CRP: r = 0.386, p = 0.001; IL-6: r = 0.384; TNF-α: r = 0.255, p = 0.037.

CONCLUSIONS

In the acute phase of SVT, most of the circulating inflammatory markers were increased and most of their levels decreased after 12 weeks. Levels of inflammatory markers were negatively correlated with the recanalization rate.

Treatment of Lower Extremity Superficial Thrombophlebitis

CLINICAL QUESTION

Which treatments for lower extremity superficial thrombophlebitis (ST) are associated with lower rates of venous thromboembolic events (VTEs) vs placebo?

BOTTOM LINE

A dose of 2.5 mg of fondaparinux administered subcutaneously once daily for 45 days is associated with fewer cases of symptomatic VTE without an increase in major bleeding vs placebo. Low-molecular-weight heparin (LMWH) and nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with lower rates of ST extension or recurrence vs placebo, but data regarding symptomatic VTE remain inconclusive. Oral rivaroxaban requires further evaluation.

Treatment for superficial thrombophlebitis of the leg

BACKGROUND

The optimal treatment of superficial thrombophlebitis (ST) of the legs remains poorly defined. While improving or relieving the local painful symptoms, treatment should aim at preventing venous thromboembolism (VTE), which might complicate the natural history of ST. This is the third update of a review first published in 2007.

OBJECTIVES

To assess the efficacy and safety of topical, medical, and surgical treatments for ST of the leg in improving local symptoms and decreasing thromboembolic complications.

SEARCH METHODS

For this update, the Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register (March 2017), CENTRAL (2017, Issue 2), and trials registries (March 2017). We handsearched the reference lists of relevant papers and conference proceedings.

SELECTION CRITERIA

Randomised controlled trials (RCTs) evaluating topical, medical, and surgical treatments for ST of the legs that included people with a clinical diagnosis of ST of the legs or objective diagnosis of a thrombus in a superficial vein.

DATA COLLECTION AND ANALYSIS

Two authors assessed the trials for inclusion in the review, extracted the data, and assessed the quality of the studies. Data were independently extracted from the included studies and any disagreements resolved by consensus. We assessed the quality of the evidence using the GRADE approach.

MAIN RESULTS

We identified three additional trials (613 participants), therefore this update considered 33 studies involving 7296 people with ST of the legs. Treatment included fondaparinux; rivaroxaban; low molecular weight heparin (LMWH); unfractionated heparin (UFH); non-steroidal anti-inflammatory drugs (NSAIDs); compression stockings; and topical, intramuscular, or intravenous treatment to surgical interventions such as thrombectomy or ligation. Only a minority of trials compared treatment with placebo rather than an alternative treatment and many studies were small and of poor quality. Pooling of the data was possible for few outcomes, and none were part of a placebo-controlled trial. In one large, placebo-controlled RCT of 3002 participants, subcutaneous fondaparinux was associated with a significant reduction in symptomatic VTE (risk ratio (RR) 0.15, 95% confidence interval (CI) 0.04 to 0.50; moderate-quality evidence), ST extension (RR 0.08, 95% CI 0.03 to 0.22; moderate-quality evidence), and ST recurrence (RR 0.21, 95% CI 0.08 to 0.54; moderate-quality evidence) relative to placebo. Major bleeding was infrequent in both groups with very wide CIs around risk estimate (RR 0.99, 95% CI 0.06 to 15.86; moderate-quality evidence). In one RCT on 472 high-risk participants with ST, fondaparinux was associated with a non-significant reduction of symptomatic VTE compared to rivaroxaban 10 mg (RR 0.33, 95% CI 0.03 to 3.18; low-quality evidence). There were no major bleeding events in either group (low-quality evidence). In another placebo-controlled trial, both prophylactic and therapeutic doses of LMWH (prophylactic: RR 0.44, 95% CI 0.26 to 0.74; therapeutic: RR 0.46, 95% CI 0.27 to 0.77) and NSAIDs (RR 0.46, 95% CI 0.27 to 0.78) reduced the extension (low-quality evidence) and recurrence of ST (low-quality evidence) in comparison to placebo, with no significant effects on symptomatic VTE (low-quality evidence) or major bleeding (low-quality evidence). Overall, topical treatments improved local symptoms compared with placebo, but no data were provided on the effects on VTE and ST extension. Surgical treatment combined with elastic stockings was associated with a lower VTE rate and ST progression compared with elastic stockings alone. However, the majority of studies that compared different oral treatments, topical treatments, or surgery did not report VTE, ST progression, adverse events, or treatment adverse effects.

AUTHORS' CONCLUSIONS

Prophylactic dose fondaparinux given for 45 days appears to be a valid therapeutic option for ST of the legs for most people. The evidence on topical treatment or surgery is too limited and does not inform clinical practice about the effects of these treatments in terms of VTE. Further research is needed to assess the role of rivaroxaban and other direct oral factor-X or thrombin inhibitors, LMWH, and NSAIDs; the optimal doses and duration of treatment in people at various risk of recurrence; and whether a combination therapy may be more effective than single treatment. Adequately designed and conducted studies are required to clarify the role of topical and surgical treatments.