Endovascular management of iliac vein compression (May-Thurner) syndrome

Final 3-Year Study Outcomes from the Evaluation of the Zilver Vena Venous Stent for the Treatment of Symptomatic Iliofemoral Venous Outflow Obstruction (The VIVO Clinical Study)

PURPOSE

To report 3-year outcomes from a prospective, multicenter, nonrandomized, single-arm study designed to assess the safety and effectiveness of the Zilver Vena Venous Stent for the treatment of symptomatic iliofemoral venous outflow obstruction.

MATERIALS AND METHODS

The VIVO study included patients with symptomatic obstruction of 1 iliofemoral venous segment (ie, 1 limb), characterized by a Clinical, Etiological, Anatomic, Pathophysiology (CEAP) clinical classification of ≥3 or a Venous Clinical Severity Score (VCSS) for pain of ≥2. Patients were retrospectively grouped based on baseline clinical presentation as postthrombotic syndrome (PTS), nonthrombotic iliac vein (NIVL) obstruction, or acute deep vein thrombosis (aDVT). Clinical improvement was assessed by change in VCSS, Venous Disability Score, Chronic Venous Disease Quality of Life Questionnaire (CIVIQ-20) scores, and CEAP C classification. Stent performance was evaluated by rates of patency by ultrasound (US), freedom from clinically driven reintervention, and freedom from stent fracture.

RESULTS

The 3-year results for the 243 patients in the VIVO cohort included a 90.3% rate of patency by US and a 92.6% rate of freedom from clinically driven reintervention. The 3-year rates of patency by US for the NIVL, aDVT, and PTS groups were 100%, 84.0%, and 86.1%, respectively. Sustained clinical improvement through 3 years was demonstrated by changes in VCSS, Venous Disability Score, CIVIQ-20, and CEAP C classification. No stent fractures were observed.

CONCLUSIONS

The VIVO study demonstrated sustained high rates of patency and freedom from clinically driven reintervention and improvements in venous clinical symptoms through 3 years. Each patient group (NIVL, aDVT, and PTS) showed clinical improvement and sustained patency through 3 years; some variation existed among groups (eg, only the NIVL group had a 100% patency rate).

Indications, technical aspects, and outcomes of stent placement in chronic iliofemoral venous obstruction

BACKGROUND

Iliofemoral Venous Stent Placement (IVS) has evolved to a well-established endovascular treatment modality for chronic iliofemoral venous obstruction (CIVO). Dedicated venous stents gained FDA approval in 2019 and solidified IVS as a defined intervention with clear indications, contraindications, risks, benefits, and procedural management principles. This review focuses on the indications, technical aspects and outcomes of stenting for CIVO. Other aspects pertaining to IVS are covered in manuscripts that are part of this series.

METHODS

This study conducted a literature search limited to English articles. Three search strategies were employed, and references were managed in Covidence software. Four investigators independently screened and evaluated articles, excluding meta-analyses, clinical trial protocols, and non-relevant studies. Eligible studies, focused on clinical outcomes and stent patencies, underwent thorough review.

RESULTS

The literature search yielded 1,704 studies, with 147 meeting eligibility criteria after screening and evaluation. Exclusions were based on duplicates, irrelevant content, and non-iliac vein stent placement.

CONCLUSION

Successful IVS for CIVO relies on meticulous patient selection, consistent use of IVUS during procedures, and attention to the technical details of IVS.

Initial experience with the ambulatory management of acute iliofemoral deep vein thrombosis with May-Thurner syndrome with percutaneous mechanical thrombectomy, angioplasty and stenting

OBJECTIVE

Patients undergoing intervention for acute iliofemoral deep vein thrombosis (IFDVT) with May-Thurner syndrome (MTS) typically require inpatient (IP) hospitalization for initial treatment with anticoagulation and management with pharmacomechanical thrombectomy. Direct oral anticoagulants and percutaneous mechanical thrombectomy (PMT) devices offer the opportunity for outpatient (OP) management. We describe our approach with these patients.

METHODS

Patients receiving intervention for acute IFDVT from January 2020 through October 2022 were retrospectively reviewed. Patients undergoing unilateral thrombectomy, venous angioplasty, and stenting for IFDVT with MTS comprised the study population and were divided into two groups: (1) patients admitted to the hospital and treated as IPs and (2) patients who underwent therapy as OPs. The two groups were compared regarding demographics, risk factors, procedural success, complications, and follow-up.

RESULTS

A total of 92 patients were treated for IFDVT with thrombectomy, angioplasty, and stenting of whom 58 comprised the IP group and 34 the OP group. All 92 patients underwent PMT using the Inari ClotTriever (Inari Medical), intravascular ultrasound, angioplasty, and stenting with 100% technical success. Three patients in the IP group required adjuvant thrombolysis. There was no difference in primary patency of the treated IFDVT segment at 12 months between the two groups (IP, 73.5%; OP, 86.7%; P = .21, log-rank test).

CONCLUSIONS

Patients with acute IFDVT and MTS deemed appropriate for thrombectomy and iliac revascularization can be managed with initiation of ambulatory direct oral anticoagulant therapy and subsequent return for ambulatory PMT, angioplasty, and stenting. This approach avoids the expense of IP care and allows for effective use of resources at a time when staffing and supply chain shortages have led to inefficiencies in the provision of IP care for nonemergent conditions.

Technical Feasibility and Clinical Efficacy of Iliac Vein Stent Placement in Adolescents and Young Adults with May-Thurner Syndrome

PURPOSE

To report technical feasibility and clinical efficacy of iliac vein stent placement in adolescent patients with May-Thurner Syndrome (MTS).

MATERIALS AND METHODS

Single-institution retrospective review of the medical record between 2014 and 2021 found 63 symptomatic patients (F = 40/63; mean age 16.1 years, 12-20 years) who underwent left common iliac vein (LCIV) stent placement for treatment of LCIV compression from an overriding right common iliac artery, or equivalent (n = 1, left IVC). 32/63 (50.7%) patients presented with non-thrombotic iliac vein lesions (NIVL). 31/63 (49.2%) patients presented with deep vein thrombosis of the lower extremity and required catheter-directed thrombolysis after stent placement (tMTS). Outcomes include technically successful stent placement with resolution of anatomic compression and symptom improvement. Stent patency was monitored with Kaplan-Meier analysis at 3, 6, 12, 24, and 36 months. Anticoagulation and antiplatelet (AC/AP) regimens were reported.

RESULTS

Technical success rate was 98.4%. 74 bare-metal self-expanding stents were placed in 63 patients. Primary patency at 12, and 24-months was 93.5%, and 88.9% for the NIVL group and 84.4% and 84.4% for the tMTS group for the same period. Overall patency for the same time intervals was 100%, and 95.4% for the NIVL group and 96.9%, and 96.9% for the tMTS group. Procedural complication rate was 3.2% (2/63) with no thrombolysis-related bleeding complications. Clinical success was achieved in 30/32 (93.8%) and 29/31 (93.5%) patients with tMTS and NIVL groups, respectively.

CONCLUSION

CIV stent placement in the setting of tMTS and NIVL is technically feasible and clinically efficacious in young patients with excellent patency rates and a favorable safety profile.

Acute left iliofemoral vein thrombosis: Comparison between simple and bony May-Thurner syndrome in CT venography

OBJECTIVES

To explore the etiology of May-Thurner syndrome (MTS) with acute iliofemoral deep vein thrombosis (DVT) regarding imaging findings and clinical features.

METHODS

We retrospectively analyzed 57 patients with acute left iliofemoral DVT from 2015 to 2020. The diameter of left common iliac vein (LCIV) at the maximal compression site and its percent compression regarding the average diameter of the uncompressed iliac vein were recorded in central and distal portions of the LCIV according to the location in the quadrant of lumbar vertebral body. Compression was categorized into simple and bony MTS; Simple MTS as LCIV compressed by the right common iliac artery (RCIA) versus Bony MTS as LCIV by lower lumbar degenerative changes regardless of RCIA compression. Initial computed tomographic venography (CTV) regarding chronic change of LCIV such as fibrotic atrophy or cordlike obliteration, extent of thrombus, and lumbar degenerative changes were evaluated. Therapeutic effect after initial therapy was assessed in follow-up CTVs after 3-6 months.

RESULTS

All patients showed LCIV compression with 19 simple MTS (mean age, 42.8 ± 14.1 years [23-67 years]; 12 females; symptom for 4.4 ± 5.5 days) and 38 bony MTS (mean age, 73.0 ± 10.2 years [49-85 years]; 26 females; symptom for 5.5 ± 4.8 days). There was significant difference in age (p < .001) and no significant difference in sex or symptom duration between two groups (p = .691 and 0.415, respectively). All simple MTS showed compression only in the central LCIV and half of bony MTS showed compression in both central and distal LCIV (p < .001). Among the lumbar degenerative changes, symmetric anterolateral osteophyte (p < .001) and asymmetric osteophyte (p < .001) were significantly associated with bony MTS, but not scoliosis (p = .799), compared to simple MTS. Although there was no significant difference in chronic change of LCIV, thrombosis extent, and therapeutic effect between two groups (p > .05), chronic change of LCIV showed significant difference between single and dual compression (23.7% vs. 57.9%, p = .024) and residual thrombus after initial therapy was occurred in 21.1% of single compression and 47.4% in dual compression with non-significant trend (p = .082).

CONCLUSION

Bony MTS related to lumbar degenerative changes with acute iliofemoral DVT occurs in older patients, presenting more than one stenosis at LCIV, inducing more chronic change with possibly weaker therapeutic effect than simple MTS.

Enhanced thrombolytic effect induced by acoustic cavitation generated from nitrogen-doped annealed nanodiamond particles

In biomedical research, ultrasonic cavitation, especially inertial cavitation (IC) has attracted extensive attentions due to its ability to induce mechanical, chemical and thermal effects. Like ultrasound contrast agent (UCA) microbubbles or droplets, acoustic cavitation can be effectively triggered beyond a certain pressure threshold through the interaction between ultrasound and nucleation particles, leading to an enhanced thrombolytic effect. As a newly developed nanocarbon material, nitrogen-doped annealed nanodiamond (N-AND) has shown promising catalytic performance. To further explore its effects on ultrasonic cavitation, N-AND was synthesized at the temperature of 1000 °C. After systematic material characterization, the potential of N-AND to induce enhanced IC activity was assessed for the first time by using passive cavitation detection (PCD). Based on experiments performed at varied material suspension concentration and cycle number, N-AND demonstrated a strong capability to generate significant cavitation characteristics, indicating the formation of stable bubbles from the surface of the materials. Furthermore, N-AND was applied in the in vitro thrombolysis experiments to verify its contribution to ultrasound thrombolysis. The influence of surface hydrophobicity on the cavitation potentials of ND and N-AND was innovatively discussed in combination with the theory of mote-induced nucleation. It is found that the cavitation stability of N-AND was better than that of the commercial UCA microbubbles. This study would provide better understanding of the potential of novel carbonous nanomaterials as cavitation nuclei and is expected to provide guidance for their future biomedical and industrial applications.

CFD Study of the Effect of the Angle Pattern on Iliac Vein Compression Syndrome

Iliac vein compression syndrome (IVCS, or May-Thurner syndrome) occurs due to the compression of the left common iliac vein between the lumbar spine and right common iliac artery. Because most patients with compression are asymptomatic, the syndrome is difficult to diagnose based on the degree of anatomical compression. In this study, we investigated how the tilt angle of the left common iliac vein affects the flow patterns in the compressed blood vessel using three-dimensional computational fluid dynamic (CFD) simulations to determine the flow fields generated after compression sites. A patient-specific iliac venous CFD model was created to verify the boundary conditions and hemodynamic parameter set in this study. Thirty-one patient-specific CFD models with various iliac venous angles were developed using computed tomography (CT) angiograms. The angles between the right or left common iliac vein and inferior vena cava at the confluence level of the common iliac vein were defined as α1 and α2. Flow fields and vortex locations after compression were calculated and compared according to the tilt angle of the veins. Our results showed that α2 affected the incidence of flow field disturbance. At α2 angles greater than 60 degrees, the incidence rate of blood flow disturbance was 90%. In addition, when α2 and α1 + α2 angles were used as indicators, significant differences in tilt angle were found between veins with laminar, transitional, and turbulent flow (p < 0.05). Using this mathematical simulation, we concluded that the tilt angle of the left common iliac vein can be used as an auxiliary indicator to determine IVCS and its severity, and as a reference for clinical decision making.

Successful Intravascular Ultrasound-Guided Thrombus Removal and Angioplasty for Phlegmasia Cerulea Dolens in a Young Male With a History of Multiple Lower Extremity Deep Vein Thrombosis

Phlegmasia cerulea dolens is a rare and severe form of deep venous thrombosis (DVT), characterized by an extensive thrombus burden and compromised venous outflow. We present the case of a 28-year-old male with a history of bilateral lower extremity DVTs and multiple venous stents who presented with acute-onset pain and swelling in the left lower extremity. Diagnostic imaging confirmed an acute DVT extending throughout the left lower extremity, including the external iliac vein. Given the diagnosis of phlegmasia cerulea dolens, a multidisciplinary approach involving interventional cardiology, orthopedic surgery, and vascular surgery was adopted. Intravascular ultrasound (IVUS)-guided thrombus removal and angioplasty were performed to restore venous outflow and improve limb perfusion. The procedure successfully removed a significant amount of thrombus and improved flow throughout the venous system. The patient exhibited an excellent clinical response, with pain resolution and improved perfusion. This case highlights the challenges and effectiveness of a combined intervention in managing complex phlegmasia cerulea dolens cases with previous venous stents.

Effect of stent treatment on hemodynamics in iliac vein compression syndrome with collateral vein

BACKGROUND

Iliac vein compression syndrome (IVCS) leads to blood flow obstruction in the lower extremities and is usually treated with stents, but stenting may worsen the hemodynamics and increase the risk of thrombosis in the iliac vein. The present work evaluates the advantages and disadvantages of the stent on IVCS with a collateral vein.

METHODS

The computational fluid dynamics method is adopted to analyze the preoperative and postoperative flow fields in a typical IVCS. The geometric models of the iliac vein are constructed from medical imaging data. The porous model is used to simulate the flow obstruction in IVCS.

RESULTS

The preoperative and postoperative hemodynamic characteristics in the iliac vein are obtained, e.g., the pressure gradient at two ends of the compressive region and the wall shear stress. It is found that the stenting restores the blood flow in the left iliac vein.

CONCLUSION

Impacts of the stent are classified into short-term and long-term effects. The short-term effects are beneficial in relieving IVCS, i.e., shortening the blood stasis and reducing the pressure gradient. The long-term effects increase the risk of thrombosis in the stent, i.e., enlarging wall shear stress due to a large corner and a diameter constriction in the distal vessel, and suggests the need to develop a venous stent for IVCS.

Deep venous stenting in females

Deep venous stenting has gained increasing prominence in recent years. This issue focuses on special considerations in female patients. The specific challenge relates to the fact that these patients are often much younger than those in whom arterial stents are placed. The stents have to perform adequately over potentially 60 years- and there is no data of that length available.

Predictors of long-term outcomes after catheter-directed thrombolysis combined with stent implantation in acute deep vein thrombosis secondary to iliac vein compression

The purpose of this study is to analyze predictive factors for long-term clinical outcomes after catheter-directed thrombolysis (CDT) combined with stent implantation for acute deep vein thrombosis (DVT) secondary to iliac vein compression (IVC). A retrospective analysis was performed to review clinical data and follow-up information on 52 patients who underwent CDT combined with stent implantation for acute DVT secondary to IVC from June 2015 to March 2020. Clinical outcomes including stent patency and incidence of postthrombotic syndrome (PTS) were investigated using Kaplan-Meier analysis. All included patients were categorized into 2 groups according to the presence of PTS. Potential risk factors, including age, gender, degree of iliac vein stenosis, time from onset to treatment, dosage of thrombolytic agent, stent extending below the inguinal ligament, and duration of anticoagulation for PTS were evaluated using multivariate logistic regression analysis. Over a median follow-up of 24 months, 4 individuals underwent reintervention due to in-stent stenosis or stent compression. Primary stent patency was 98.1% at 1 month, 94.2% at 6 months, 90.4% at 12 months, and 88.5% at 24 months. Freedom from PTS was 98.1% at 6 months, 84.6% at 12 months, and 75% at 24 months. No treatment-related mortality or morbidity was observed. Based on the development of PTS, 13 patients with PTS were classified into group A and 39 patients without PTS were regarded as group B. Upon multivariate logistic regression analysis, key prognostic factors for PTS were degree of iliac vein stenosis and time from onset to treatment. CDT combined with stent implantation is safe and effective for acute DVT secondary to IVC in the long-term perspective. Severe iliac vein stenosis and longer period from onset to treatment may be associated with a higher risk of PTS.

Management of May Thurner Syndrome in Pregnant Patients

May Thurner Syndrome contributes to thromboembolic disease and can cause significant morbidity in pregnant patients secondary to exaggerated anatomic relationships and physiologic changes in the hematologic system favoring thrombogenesis. Because this condition is both underrecognized and underreported, management in pregnant and postpartum patients is based on expert opinion without any formal evidence-based guidance. Herein, we review five pregnancies in four patients with May Thurner Syndrome and general management strategies. Through collaborative and multidisciplinary care, patients with May Thurner Syndrome can be safely and successfully managed during pregnancy and the postpartum period with appropriate anticoagulation.

May–Thurner Syndrome: A Forgotten Cause of Deep Vein Thrombosis

May–Thurner syndrome (MTS) is a relatively rare vascular condition that is characterized by external compression of the left common iliac vein by the right common iliac artery against the fifth lumbar vertebra. This condition slows the blood flow and is a predisposing factor for deep vein thrombosis (DVT). The key to its successful treatment is to remove the clot and fix the anatomical lesion. If this MTS diagnosis is missed, the recurrence of thrombosis will lead to significant morbidity and mortality. We report a case of 70-year-old female who had left leg DVT caused by MTS and was treated with catheter-directed thrombolysis along with long-term anticoagulation.

A systematic review of current trends in pharmacologic management after stent placement in nonthrombotic iliac vein lesions

Objective

Stenting of the iliac vein is increasingly recognized as a treatment for chronic venous insufficiency (CVI). However, the pharmacologic management after stent placement is unclear. This review was conducted to illustrate recent trends in anticoagulation and antiplatelet regimens following stent placement for nonthrombotic iliac vein lesions (NIVL).

Methods

The MEDLINE database was searched using the term “iliac vein stent.” Retrieval of articles was limited to studies conducted on humans and published in English between 2010 and 2020. Studies were included that described iliac vein stent placement. Studies were excluded that contained fewer than 25 patients, performed procedures other than stent placement, did not specify the postoperative anticoagulant used, or treated lesions of thrombotic origin.

Results

12 articles were included in this review, yielding a total of 2782 patients with a male-to-female ratio of 0.77. The predominant CEAP classification encountered was C3. The most common stent used in the included studies was the Wallstent (9/12), and the most common pharmacologic regimen was 3 months of clopidogrel (6/12). Warfarin, aspirin, cilostazol, and rivaroxaban were among other agents used. Primary stent patency ranged from 63.1 to 98.3%. There was no apparent correlation between pharmacologic agent used and stent patency or subjective patient outcomes.

Conclusion

Multiple different approaches are being taken to pharmacologically manage patients following stent placement for NIVL. There is no consensus on which agent is best, nor is there a formal algorithmic approach for making this decision. Additionally, the findings in this study call into question whether anticoagulation following stenting for NIVL is necessary at all, given the similar outcomes among the different agents utilized. This review underscores the potential value of undertaking a multi-institutional prospective study to determine what is the best pharmacologic therapy following venous stent placement for NIVL.

A Case of a Pediatric Patient With Protein S Heerlen Polymorphism and Deep Venous Thrombosis

Hereditary protein S (PS) deficiency is a rare autosomal dominant disorder with increased risk of venous thromboembolism. The PS Heerlen polymorphism at codon 501 of the PROS1 gene is considered a variant of uncertain significance. It has since been shown that PS Heerlen has a reduced half-life, resulting in reduced levels of free PS. We report a case of an adolescent female with May Thurner syndrome and heterozygous PS Heerlen mutation resulting in a mild PS deficiency and venous thromboembolism. With this nonmodifiable risk factor, the patient received prolonged anticoagulation with strong consideration for lifelong prophylaxis.

Endovascular Management of Venous Thromboembolic Disease in the Oncologic Patient Population

PURPOSE OF REVIEW

Venous thromboembolic disease causes significant mortality and morbidity in the oncologic patient population. Recently, minimally invasive endovascular technologies have been developed as an adjunct to antithrombotic therapy for the management of DVT and PE. The current and potential roles for endovascular treatment of cancer-associated venous thromboembolism (VTE) will be reviewed in this article.

RECENT FINDINGS

The recent NCCN guidelines recommend endovascular therapy in patients eligible for therapeutic anticoagulation who present with life-, organ-, or limb-threatening thrombosis. However, symptomatic non-life-threatening VTE can negatively affect QOL and physical function, both of which have prognostic implications in the cancer population. Endovascular therapies have been shown to improve physical function and QOL in prospective trials performed in a non-oncologic patient population as well as small retrospective studies in the cancer population. In addition to treating life- and limb-threatening thrombosis, endovascular therapy for VTE can improve QOL and physical function in comparison to anticoagulation alone. Prospective trials are warranted to assess the benefit of endovascular therapy for quality of life-years, performance status, and overall survival in the oncologic patient population.

Direct Iliac Vein Stenting in Phlegmasia Cerulea Dolens Caused by May-Thurner Syndrome

Phlegmasia cerulea dolens (PCD) is an uncommon but potentially limb-threatening complication of acute deep vein thrombosis. A 56-year-old male presented with PCD. Color Doppler ultrasonography revealed extensive thrombosis of the left superficial and common femoral and external and common iliac veins. After an unsuccessful iliofemoral thrombectomy, contrast-enhanced computed tomography revealed iliofemoral deep vein thrombosis due to May-Thurner syndrome (MTS). After the deployment of an inferior vena cava filter, the thrombotic occlusion was traversed with a guidewire and direct stenting was performed to achieve immediate recanalization. The patient was discharged two days after the procedure, demonstrating significant clinical improvement. MTS is a rare cause of PCD. Direct iliac vein stenting may be a safe and effective alternative treatment for rapid recanalization if percutaneous mechanical thrombectomy devices are unavailable.

Three-Year Results from the Venovo Venous Stent Study for the Treatment of Iliac and Femoral Vein Obstruction

Purpose

To assess safety and patency of the Venovo venous stent for the treatment of iliofemoral vein obstruction.

Materials and Methods

Twenty-two international centers enrolled 170 patients in the VERNACULAR study (93 post-thrombotic syndrome; 77 non-thrombotic iliac vein lesions). Primary outcome measures were major adverse events at 30 days and 12-month primary patency (freedom from target vessel revascularization, thrombotic occlusion, or stenosis > 50%). Secondary outcomes included the Venous Clinical Severity Score Pain Assessment and Chronic Venous Quality-of-Life Questionnaire assessments (hypothesis tested). Secondary observations included primary patency, target vessel and lesion revascularization (TVR/TLR), and assessment of stent integrity through 36 months.

Results

Freedom from major adverse events through 30 days was 93.5%, statistically higher than a pre-specified performance goal of 89% (p = 0.032) while primary patency at 12 months was 88.6%, also statistically higher than a performance goal of 74% (p < 0.0001). Mean quality-of-life measures were statistically improved compared to baseline values at 12 months (p < 0.0001). Primary patency at 36 months was 84% (Kaplan–Meier analysis) while freedom from TVR/TLR was 88.1%. There was no stent embolization/migration, and no core laboratory assessed stent fractures reported through 36 months. Six deaths were reported; none adjudicated as device or procedure related.

Conclusion

The Venovo venous stent was successfully deployed in obstructive iliofemoral vein lesions and met the pre-specified primary outcome measures through 12 months. At 3 years, primary patency was 84%, reintervention rates were low, standardized quality-of-life and pain measures improved from baseline, and there was no stent migration or fractures.

Level of Evidence

Level 2—prospective, multicenter, controlled clinical study without a concurrent control or randomization. Pre-specified endpoints were hypothesis-tested to performance goals derived from peer-reviewed clinical literature.

Registration clinicaltrials.gov

Unique Identifier NCT02655887.

[Diagnosis of arteriovenous compression in small pelvic varicose veins]

AIM

The study was aimed at assessing the incidence of arteriovenous compression in women with chronic venous insufficiency of the inferior vena cava and at developing an optimal diagnostic algorithm.

PATIENTS AND METHODS

During the period 2019-2020, we performed a cross-sectional study including a total of sixty-six 18-to-55-year-old (mean 33.5±5.0) women with clinical manifestations of chronic venous insufficiency of the basin of the inferior vena cava. A diagnostic algorithm included questionnaire, transvaginal ultrasound examination, multislice computed tomography, direct phlebography in combination with phlebotonometry.

RESULTS

Chronic venous insufficiency of lower limbs was diagnosed in 66 (100%) cases and was presented by the following clinical classes according to the CEAP classification: C0 - 4.5%, C1 - 60.6%, C2 - 27.2%, C3 - 3%. Symptoms of pelvic venous plethora were revealed in 36 (55.5%) examined patients. Arteriovenous compression syndrome according to the findings of multislice computed tomography was verified in 16 (24%) women, including May-Turner syndrome in 5 (7.6%), aortomesenteric compression syndrome in 8 (12%) women, with a combination of both syndromes observed in 3 cases; the frequency of their detection did not differ statistically in subgroups of women with and without clinical signs pelvic varicose veins. Direct phlebography in combination with phlebotonometry was performed in 9 women, the diagnosis of arteriovenous compression (May-Thurner syndrome) was confirmed in 1 case only.

CONCLUSION

In women with signs of chronic venous insufficiency in the system of the inferior vena cava the frequency of detecting arteriovenous compression on multislice computed tomography may reach 24% and does not depend on the presence of symptoms of pelvic venous plethora. The proportion of arteriovenous compression according to the findings of direct phlebography and phlebotonometry in the structure of causes of the development of pelvic varicose veins did not exceed 11%. An algorithm for diagnosing arteriovenous compression syndromes should obligatorily include multislice computed tomography, direct phlebography and phlebotonometry.

May-Thurner syndrome with inferior mesenteric vein drainage and porta system - Case report

We present the case of a 12-year-old girl with a history of vascular anomalies in the lower pelvic limbs and back, who developed unilateral deep vein thrombosis of the left lower limb after her pubertal development, she was diagnosed with May-Thurner syndrome with an abnormal venous drainage of the pelvic structures through the superior hemorrhoidal veins to the inferior mesenteric vein towards the porta system, this being a chronic manifestation. This kind of behavior has not been documented in the reviewed medical literature. Secondarily, balloon angioplasty was performed without breaking the stenotic ring. As a second attempt, it was decided to place the venous stent, with satisfactory resolution of the symptoms. There are controversies about the indications for the use of anticoagulants and antiplatelet agents, or the indications to place a venous stent in children. We must consider an approach to for effective therapeutic treatment in these cases is to control bleeding, the main goal being trying to avoid ulcerations in the lower limb due to venous insufficiency with irreversible affectation of the valvular system.

May-Thurner Anatomy in Patients With Chronic Thromboembolic Pulmonary Hypertension: An Important Clinical Association

OBJECTIVES

The aim of this study was to investigate the incidence of May-Thurner anatomy (MTA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH) and identify its predictors.

BACKGROUND

MTA is an anatomical variant characterized by compression of left common iliac vein by the overlying right iliac artery. Over time, this leads to venous intimal scarring, blood flow stasis, and the development of deep vein thrombosis (DVT). DVT is a known risk factor for the development of CTEPH. The prevalence of this anatomical variation in patients with CTEPH is unknown.

METHODS

A retrospective chart review was conducted in patients referred to Temple University Hospital's cardiac catheterization laboratory for the evaluation of CTEPH between January 2016 and June 2020. Among these patients, those who underwent invasive venography were evaluated for the presence of angiographic MTA. Multivariate regression was used to identify factors associated with presence of MTA.

RESULTS

A total of 193 patients with CTEPH were referred for pulmonary angiography, of whom 148 patients underwent invasive venography. MTA was identified in 44 patients (29.7%). Factors associated with the presence of MTA were lower extremity DVT (odds ratio: 3.5; 95% confidence interval: 1.58-7.8; P = 0.002), and left lower extremity post-thrombotic syndrome (odds ratio: 2.0; 95% confidence interval: 0.98-4.1; P = 0.05). Patients with MTA were more likely to undergo pulmonary thromboendarterectomy than patients without MTA (79.5% vs 58.7%; P = 0.015).

CONCLUSIONS

MTA is very common in patients with CTEPH. History of lower extremity DVT and or left lower extremity post-thrombotic syndrome was associated with the presence of MTA.

Comparison of Anticoagulation Regimens Following Stent Placement for Nonthrombotic Lower Extremity Venous Disease

PURPOSE

To determine whether subtherapeutic anticoagulation regimens are noninferior to therapeutic anticoagulation regimens following stent placement for nonthrombotic lower extremity venous disease.

MATERIALS AND METHODS

Fifty-one consecutive patients (88% women; mean age, 44 years) who underwent stent placement for nonthrombotic lower extremity venous disease between 2002 and 2016 were retrospectively identified. The patients were divided into 2 cohorts: those who received prophylactic enoxaparin or no anticoagulation (subtherapeutic) after the procedure and those who received therapeutic doses of anticoagulation with enoxaparin, warfarin, and/or rivaroxaban (therapeutic) after the procedure. Baseline demographic characteristics, procedure characteristics, and outcomes were compared between the 2 groups using the Student t test, Fisher exact test, and χ² test. The subtherapeutic and therapeutic anticoagulation groups did not differ significantly in the baseline demographic characteristics (eg, sex, race, and age) or procedure characteristics (eg, number of stents placed, stent brand, stent diameter, etc).

RESULTS

The mean clinical follow-up time was 4.4 years (range, 0-16.3 years). There were no thrombotic adverse events or luminal obstructions due to in-stent restenosis in either group. There were 5 minor bleeding adverse effects in the therapeutic group and no bleeding adverse effects in the subtherapeutic group (P = .051). There were no statistically significant differences in subjective symptom improvement (P = .75).

CONCLUSIONS

In this retrospective cohort, the subtherapeutic and therapeutic anticoagulation regimens produced equivalent outcomes in terms of adverse event rates, reintervention rates, and symptomatic improvement, suggesting that therapeutic doses of anticoagulation do not improve outcomes compared with subtherapeutic anticoagulation regimens following nonthrombotic venous stent placement.

May-Thurner Syndrome: A Rare Case of Unilateral Deep Vein Thrombosis in an Elderly Woman

Patient: Female, 78-year-old

Final Diagnosis: May-Thurner syndrome

Symptoms: Lower extremity edema • lower extremity pain

Medication: —

Clinical Procedure: —

Specialty: Critical Care Medicine • Hematology • General and Internal Medicine • Radiology

An Anomalous Cause of Deep Venous Thrombosis: A Case Report

Introduction

Lower extremity deep venous thrombosis (DVT) is a common diagnosis in the emergency department (ED). Deep venous thromboses can be the result of anatomical variation in the vasculature that predisposes the patient to thrombosis. May-Thurner syndrome (MTS) is one such anatomic variant defined by extrinsic compression of the left common iliac vein between the right common iliac artery and lumbar vertebrae.

Case Report

We report such a case of a 39-year-old woman with no risk factors for thromboembolic disease who presented to the ED with extensive unilateral leg swelling and was ultimately diagnosed with MTS.

Conclusion

This diagnosis is an important consideration particularly in patients who are young, female, have scoliosis or spinal abnormalities, or are at low risk for DVT yet who present with extensive lower extremity swelling and are found to have proximal thrombus burden. Often further imaging, anticoagulation, angioplasty, or thrombectomy are indicated to prevent morbidity and post-thrombotic syndrome in these patients.

Treatment of May-Thurner's Syndrome and Associated Complications: A Multicenter Experience

OBJECTIVE

To assess the treatment options and associated complications in patients with May-Thurner's syndrome (MTS).

METHODS

We retrospectively reviewed the charts of patients diagnosed with MTS. Thorough review was completed and data relevant to methods of diagnosis, treatment, complications, hospital readmission, and mortality were extracted from patient charts. The patients were followed for two years after diagnosis.

RESULTS

Of the 47 patients identified as having "MTS", 32 (70%) were diagnosed formally with either magnetic resonance venography, computed tomography venography, or ultrasound. Two patients were excluded for insufficient availability of follow-up records. Mean age of the population included (N = 30) was 50.24 ±15.33 years and 83% (N = 25) had female gender. The majority (40%) of patients were treated with anticoagulation, thrombolysis, and stent placement, and 13.3% received a combination of anticoagulation, antiplatelet agent, thrombolysis, and stent placement. Overall, we found 28 patients (93%) who underwent endovascular stenting. However, 39.3% (11/28) had stent-related complications that included stent thrombosis, stenosis, and migration. One patient underwent open heart surgery for stent retrieval. Duration of anticoagulation therapy ranged from 6 months to lifelong. Two patients (6.7%) suffered major bleeds requiring transfusion. Fourteen patients (46.6%) developed post-thrombotic syndrome. Seven (23.3%) patients required MTS-related readmission within 30 days. No mortality was noted at two-year follow-up.

CONCLUSION

Although our study only included 30 patients, it was evident to us that there is no consensus in the management of MTS. Furthermore, endovascular stenting, which has a major role in the management of MTS, has complication rates that hover close to 40%. Further research is needed to help develop a standardized evidence-based approach in the management of MTS that ensures a decreased risk of immediate and long-term complications.

Single-stage treatment with iliac vein stenting and stripping of great saphenous veins for patients with left iliac vein compression syndrome

BACKGROUND

We sought to evaluate the safety and feasibility of single-stage treatment with left iliac vein stenting and saphenous stripping in patients with left iliac vein compression (LIVC) and left great saphenous vein (GSV) incompetence.

METHOD

s: We conducted a prospective cohort study of 72 patients diagnosed with LIVC and left GSV incompetence between June 2012 to Oct 2018. We evaluated the periprocedural, 30-day, and 1-year outcomes of venous clinical severity score (VCSS), Chronic Venous Insufficiency Questionnaire 2 (CIVIQ2), the success rate of stent placement, duration of intervention, length of hospital stay, duplex recurrence, and clinically visible recurrence.

RESULTS

There were 43 patients in the two-staged group and 29 patients in the single-staged group. The clinical characteristics of the two groups were similar. There were no differences between the two groups in the technical success rate, perioperative mortality, and surgical morbidity. There was no significant difference in the duplex and clinically visible recurrence. The length of hospital stay was significantly lower in the single-staged group. The single-staged group was associated with a higher complication rate of ecchymosis. There was no death, pulmonary embolism, or contrast-induced nephropathy among the patients. The 1-year primary patency rate was similar.

CONCLUSIONS

Both treatment approaches were equally effective and had a high technical success rate. The single-staged group had a higher complication rate of ecchymosis due to heparin applying during the procedure.

Association between Laterality and Location of Deep Vein Thrombosis of Lower Extremity and Pulmonary Embolism

Purpose

The aim of this study was to investigate the relationship between the anatomical location of thrombi in the lower extremities and the development of pulmonary embolism (PE).

Methods

Materials and We collected and analyzed the data of patients diagnosed with deep vein thrombosis (DVT) of the lower extremities between 2006 and 2015, and included those whose computed tomography (CT) data were available for PE identification. We evaluated the relationship between the laterality and the proximal/distal location of the thrombi in lower extremites and the location of PE.

Results

CT images were available for 388/452 patients with DVT. After excluding 32 cases with bilateral involvement, 356 cases were included for analysis in this study. The ratio of DVT in the left:right leg was 232:124. PEs developed in 121 (52.2%) patients with left-sided DVT and in 78 (62.9%) with right-sided DVT (P=0.052). PEs in the main pulmonary arteries developed in 36 (15.5%) patients with left leg DVT and in 30 (24.2%) with right leg DVT (P=0.045). The most frequent site of thrombosis associated with the development of PE was the left iliac vein (59/199, 29.6%). According to the anatomical segment of the leg affected by DVT, patients with DVT in the right femoral vein (50/71, 70.4%; P=0.016) had the highest rate of occurrence of PE.

Conclusion

PE develops more frequently in patients with right-sided DVT than in those with left-sided DVT. Therefore, careful observation for the possible development of PE is recommended in cases with right-sided DVT of the lower extremity.

Transient arterial insufficiency and neurologic deficit following external iliac vein stent reconstruction for malignant compression

Acute iliofemoral deep vein thrombosis may present with pain and swelling or phlegmasia cerulea dolens. When thrombosis occurs in the setting of an underlying venous obstruction, stent reconstruction should be performed after thrombus clearance to prevent rethrombosis. Stent reconstruction after thrombus clearance is associated with high technical success rates and durable patency. This report describes transient lower extremity arterial insufficiency and neurologic deficit after external iliac vein stent expansion and reconstruction within a confined space resulting from a malignant obstruction. It serves as a cautionary tale that, in rare cases, aggressive venous stenting within a confined space can transfer clinically significant forces to adjacent arteries and nerves.

A clinical guide to Deep venous stenting for chronic iliofemoral venous obstruction

INTRODUCTION

An increase in endovenous interventions for deep venous pathologies has been observed. This article aims to provide an overview of the role of venous stenting in the management of chronic conditions affecting the deep venous system of the lower limbs, with a focus on intervention relating to the vena cava and iliofemoral venous segments.

METHOD

An overview of the literature on the minimally invasive venous stenting procedures that are being increasingly used in the management of chronic conditions affecting the deep venous system of the lower limbs.

RESULTS

We discuss key areas of interest to a venous specialist practicing in this area, including diagnostic imaging in chronic deep venous disease, with a focus on the use of intravascular ultrasound in this context; treatment of chronic venous outflow obstruction, including the rationale and structural indications for stenting, current guidance regarding stent placement, and fundamental points to consider during decision-making (endophlebectomy and stenting, stenting across the inguinal ligament, optimal sizing of venous stents, extension of venous stenting to beyond the common femoral vein confluence, the role of thrombolysis useful in chronic venous disease, and arteriovenous fistulae); outcomes and initial reports of stenting; and the future of venous stents.

CONCLUSION

Deep venous stenting has become a key treatment option for chronic (thrombotic or non-thrombotic) obstructive venous disease. Dedicated venous stents and intravascular ultrasound represent important technological advances in the minimally invasive treatment of symptomatic chronic deep venous obstruction, which previously required open surgical reconstruction.

Nonnegligible causes of symptoms of acute lower extremities--3 cases of May-Thurner syndrome with deep vein thrombosis

Background

May-Thurner syndrome is a kind of disease caused by the compression of the left common iliac vein. It is one of the causes of incomplete venous valves and superficial varicose veins in lower limbs, and is also a potential factor of acute deep vein thrombosis (DVT).

Method

Here 3 cases are diagnosed as May-Thurner syndrome at different ages.

Case presentations

1. A 35-year-old female patient was hospitalized with swelling of the left lower limb for 1 week. Computed tomography (CT) showed compression of the left common iliac vein with thrombosis. May-Thurner syndrome was diagnosed and catheter-directed thrombolysis was performed. 2. A 37-year-old male patient came to our hospital due to sudden swelling of the right lower extremity and pain for 3 days. Computed tomography showed compression of the left common iliac vein and deep venous thrombosis (DVT) of the right iliac vein. May-Thurner syndrome was diagnosed. The patient was performed with inferior vena cava (IVC) filter implantation, catheter-directed thrombolysis and balloon angioplasty for right iliac vein. And the patient recovered well; 3. A 55-year-old female patient came to our hospital with swelling and discomfort in the left lower extremity for 3 days. Computed tomography showed stenosis of the left common iliac vein with deep vein thrombosis. May-Thurner syndrome was diagnosed, balloon dilation and stent implantation were performed. During 3 years of follow-up, there was no swelling or new thrombosis in her lower limbs.

Conclusion

When encountering unexplained deep vein thrombosis, iliac vein compression syndrome should be considered and treated in time to prevent the recurrence of thrombosis. Catheter-directed thrombolysis can relieve symptoms and stenting placement is the optimal way to relieve stenosis, supplemented by long-term anticoagulation therapy and graduated compression stockings.

Imaging of Pelvic Venous Disorders (PeVD); Should Every Patient Get an MRI?

Pelvic venous disease (PeVD) is part of the broad differential diagnosis of chronic pelvic pain with a challenging diagnosis and clinical workup to identify those patients that are most likely to benefit from intervention. Ultrasound, MRI, CT, venography, and intravascular ultrasound can all provide information to aid in the diagnostic algorithm. The purpose of this article is to review imaging as a component of the outpatient workup of patients with chronic pelvic pain to guide appropriate understanding and use of imaging modalities to accurately identify patients suffering from PeVD. A favored approach is to begin with transabdominal sonography with selective use of MRI/MRV in specific patient populations.

Clinical Outcomes of Stenting Extending Below the Inguinal Ligament for Treatment of Chronic Iliofemoral Venous Obstruction

BACKGROUND

Patients with chronic iliofemoral venous obstructive lesions that often require stenting extending below the inguinal ligament. However, the issue of stents crossing the inguinal ligament is currently controversial. Some guidelines suggest that it should be avoided, and some guidelines suggest that in order to ensure adequate flow, the inguinal ligament can be crossed if necessary. The aim of this study was to evaluate the technical aspects and examine patency rates of stent placement across the inguinal ligament for managing iliofemoral venous obstruction.

METHODS

A retrospective analysis of 127 patients with chronic iliofemoral venous obstruction were treated with interventional surgery in a single institution from January 2012 to January 2018 was conducted. All patients underwent balloon dilatation and placement of at least 2 stents extending below inguinal ligament. Inflow condition, technical success, operation duration, stent patency rates, anticoagulant selection and duration, and complications were recorded after the interventions.

RESULTS

The technical success rate was 100%. No major perioperative complications occurred. The mean number of stents was 2.14 ± 0.37. Follow up periods ranged from 12 to 60 months (28.79 ± 10.90 months). Overall cumulative primary, assisted primary, and secondary stent patency rates were 81.9%, 90.5%, and 92.9% at 12 months and 70.4%, 80.9%, and 86.0% at 24 months, and 64.2%, 72.3%, and 74.3% at 36months, respectively. Cumulative patency rates at 12 months, 24 months and 36 months were significantly greater in the patients with "good" inflow as compared to "fair" inflow. The symptoms of all patients improved. None of the stents were compressed, fractured or migrated.

CONCLUSIONS

Stenting across the inguinal ligament for treatment of the patients with chronic iliofemoral venous obstruction was a feasible and safe treatment with good patency and clinical results in short and midterm follow up, and stents with good inflow have better patency.

Postinterventional antithrombotic management after venous stenting of the iliofemoral tract in acute and chronic thrombosis: A systematic review

Venous stenting has become a common treatment option for central deep venous outflow obstructions and postthrombotic syndrome. Following successful recanalization and stenting, stent patency is endangered by in-stent thrombosis and recurrent venous thromboembolism. Antithrombotic therapy might reduce patency loss. This systematic review summarizes the literature on antithrombotic therapy following (post)thrombotic venous stenting. A systematic PubMed, MEDLINE, EMBASE, and Cochrane search was performed for studies addressing antithrombotic therapy prescribed following venous stenting of the iliofemoral tract indicated by acute or chronic thrombotic pathology. A total of 277 articles was identified of which 64 (56 original studies) were selected. Overall, a mean primary patency rate of 82.3% was seen 1 year after the intervention, which decreased to 73.3% after 2 years. In the majority (43 of 56 studies, 77%), treatment was based on use of vitamin K antagonists, either with (18%) or without (59%) use of antiplatelet drugs. Only two studies (4%) directly assessed the effect of antithrombotic therapy on treatment outcomes. The impact of postinterventional antithrombotic therapy on stent patency remains unknown because of limited and insufficient data available in current literature. Further clinical research should more clearly address the role of antithrombotic therapy for preservation of long-term patency following venous stenting.

The Protégé Nitinol Self-Expanding Stent for the Treatment of Iliofemoral Veno-Occlusive Disease

PURPOSE

To evaluate the safety and effectiveness of the Protégé nitinol self-expanding stent for the treatment of iliofemoral veno-occlusive disease.

MATERIALS AND METHODS

A retrospective review was performed of 376 (284 left, 92 right) Protégé stents in 212 limbs of 183 patients (mean age: 53 ± 17 years, 52% female) treated for iliofemoral veno-occlusive disease between 2011 and 2018. Binary patency was assessed with duplex ultrasound and calculated by Kaplan Meier analysis. Clinical outcomes were evaluated by clinical-etiology-anatomy-pathophysiology (CEAP) classification and Villalta scores. Adverse events were recorded and categorized per Society of Interventional Radiology reporting standards.

RESULTS

Of the 212 limbs, 125 presented with acute thrombosis and 28 with chronic thrombosis requiring thrombectomy (n = 44), catheter directed thrombolysis (n = 32), or both (n = 77). Fifty-nine limbs were non-thrombotic. Mean follow-up time was 11.44 ± 11.37 months. Kaplan Meier analysis revealed a primary limb-level patency of 92.3%, 88.6%, 86.9% and 86.9% at 6, 12, 24 and 36 months, respectively. CEAP and Villalta scores improved from a median of C3 (range: 0-6) to C1 (0-5) (p < 0.001) and from a mean of 13.4 ± 7.5 to 5.3 ± 4.9 (p < 0.001), respectively. Nine minor and 2 major adverse events were recorded.

CONCLUSIONS

Endovascular treatment of iliofemoral veno-occlusive disease with the Protégé self-expanding stent appears to have good mid-term patency.

LEVEL OF EVIDENCE

Level 4, Case Series.

An efficacy and safety study of rivaroxaban for the prevention of deep vein thrombosis in patients with left iliac vein compression treated with stent implantation (PLICTS): study protocol for a prospective randomized controlled trial

BACKGROUND

Balloon dilatation with stent implantation has been proved to be an effective option for left iliac vein compression syndrome (LIVCS), but thrombosis may still occur after the operation. Currently, warfarin is used for anticoagulant therapy, but long-term monitoring is required, while rivaroxaban does not need laboratory monitoring, which can simplify treatment. Therefore, this study aimed to compare the efficacy and safety of rivaroxaban and warfarin in anticoagulation.

METHODS

This study is a multicenter, randomized controlled trial. We will recruit 224 patients with thrombotic LIVCS from 9 hospitals. Moreover, these patients will be randomized to either the experimental group (rivaroxaban) or the control group (warfarin plus nadroparin). The primary outcome is stent occlusion rate. Secondary outcomes are quality of life scale survey results, all-cause mortality, anticoagulation-related mortality, and the proportion of participants with stent displacement/fracture, thrombosis, hemorrhage, and other vascular events.

DISCUSSION

This study will provide reliable, evidence-based clinical evidence for the efficacy and safety of rivaroxaban antithrombotic therapy after stent implantation.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04067505 . Registered on August 26, 2019.

Clinical Outcomes of May-Thurner Syndrome in Pediatric Patients: A Single Institutional Experience

Introduction  May-Thurner syndrome (MTS) is a vascular anatomic variant resulting in compression of the left common iliac vein by the right common iliac artery, affecting approximately 22% of the population. In adults, following acute deep vein thrombosis (DVT) of the iliofemoral veins, the incidence of postthrombotic syndrome (PTS) and recurrent DVT are high if treated with anticoagulation alone, warranting adjunctive treatment with thrombolysis and stent placement. However, there is paucity of literature documenting the course of treatment and associated outcomes in pediatric patients with MTS. Methods  A retrospective chart review of pediatric patients (≤ 18 years of age) with radiologic confirmation of MTS with or without DVT evaluated and/or treated at our institution from January 1, 2005 through December 31, 2015 was conducted. Results  Seventeen patients (4 male; 13 female) were identified. Median age was 15.4 years (range 8.8-17.1 years) with a median follow-up of 1.2 years (range 0.4-7.5 years). Thirteen (76.5%) patients presented with left lower extremity DVT. Management included catheter-directed thrombolysis ( n  = 5), systemic thrombolysis ( n  = 1), and mechanical thrombectomy ( n  = 1). Fifteen patients were treated with anticoagulation including two patients with endovascular stents without DVT. Median duration of anticoagulation was 6.3 months (range 3.2-18.7 months). Ten patients (59%) underwent stent placements. Complete and partial thrombus resolution was noted in six patients each and no resolution in one patient. Four patients had recurrence/progression of thrombus ( n  = 3 with stents) at a median time of 29 days (range 12-495 days). No bleeding complications were observed. Clinically documented or self-reported PTS was noted in 8 patients (62%). Conclusion  There are no clear guidelines for MTS management in children and adolescents. In our cohort, thrombolysis, anticoagulation, or stent placements were not associated with bleeding risks, with recurrence/progression of DVT and signs and symptoms of PTS noted in 30 and 62%, respectively. Further studies are needed to determine a standardized treatment approach of the pediatric patient with MTS with or without thrombosis.

Association between deep vein thrombosis and stent patency in symptomatic iliac vein compression syndrome: Systematic review and meta-analysis

BACKGROUND

The study intended to evaluate stent primary patency rates for patients with iliac vein obstruction related with iliac vein compression syndrome according to clinic presentation.

METHODS

A systematic review and meta-analysis was conducted of studies that compared: unexposed patients with nonthrombotic iliac vein lesion (NIVL, group 1) vs exposed patients with iliac acute deep vein thrombosis (DVT, group 2); and NIVL (group 1) vs exposed patients with iliac vein obstruction and post-thrombotic syndrome (PTS, group 3). The following databases were searched: EMBASE, PubMed, Web of Science, Scopus, SciELO, and LILACS. Two reviewers independently selected the potential studies and extracted data. The pooled odds ratio (OR) and 95% confidence interval (95% CI) are shown for each outcome.

RESULTS

Five studies with a total of 1050 participants and 1169 lower limbs were included. Five hundred eighty-eight lower limbs presented NIVL (50.3%), 91 lower limbs presented acute DVT (7.7%), and 490 lower limbs presented PTS (42%). The endovascular technical success rate of stenting did not differ in any of the groups: 99.6% in NIVL, 94.5% in acute DVT, and 96.5% in PTS (P = .0632). The primary stent patency rates in the 6-month follow-up were 98.3% in NIVL vs 90.9% in PTS, with a statistical difference showing reduced stent patency rates in PTS (OR, 0.17; 95% CI, 0.06-0.48; P = .0008; I² = 0%), and 100% in the NIVL group vs 91.6% in acute DVT, with no statistical difference (OR, 0.30; 95% CI, 0.06-2.32; P = .30; I² = 0%). The primary stent patency rates in the 12-month follow-up were 94.6% in NIVL vs 84.1% in PTS, with a statistical difference showing decreases stent patency rates in the PTS group (OR, 0.29; 95% CI, 0.14-0.63; P = .0008; I² = 0%), and 91.1% in NIVL vs 90.9% in acute DVT, with no statistical difference (OR, 1.03; 95% CI, 0.26-4.07; P = .96; I² = 0%).

CONCLUSIONS

There is no statistical difference for the stent primary patency rates when the treatment is conducted in NIVL as compared with acute DVT lower limbs (at 6 and 12 months); therefore, other criteria must be considered for the indication of this treatment in NIVL patients. However, because there were better results of stent primary patency rates for NIVL vs PTS patients, this finding favors the treatment of acute DVT instead of PTS in lower limbs, once PTS renders smaller stent patency rates at 6 and 12 months.

Single-Session Percutaneous Mechanical Thrombectomy Using the Aspirex®S Device Plus Stenting for Acute Iliofemoral Deep Vein Thrombosis: Safety, Efficacy, and Mid-Term Outcomes

To assess the safety, efficacy and mid-term outcomes of single-session percutaneous mechanical thrombectomy (PMT) for acute symptomatic iliofemoral deep vein thrombosis (DVT) using the Aspirex^®S device. Retrospective review of 30 patients (women, 23; mean age, 45.5 ± 19.9 years; range, 17-76) who underwent PMT with the 10-French Aspirex^®S device (Straub Medical AG, Wangs, Switzerland) for acute DVT between December 2015 and March 2019. Procedures were performed by popliteal (n = 22) or jugular (n = 7) approach, or both (n = 1). Mean time from diagnosis to PMT was 5.5 ± 4.6 days (range, 2-11). Successful thrombus removal and venous patency restoration were achieved in all patients (100%). Fluid removal was 307.8 ± 66.1 mL (range, 190-410). Additional venous stenting rate was 100%. Mean procedural time was 107.3 ± 33.9 min (range, 70-180). No major complication occurred. The patient's postprocedural course was uneventful in all cases, with hospital discharge within 2 days in 83.3%. Early in-stent rethrombosis occurred within 1 week in 3 patients, successfully managed by endovascular approach. Secondary stent patency rate was 86.7% at a mean follow-up of 22.3 ± 14.2 months (range, 6-48), as assessed by Duplex ultrasound. Single-session of PMT using the Aspirex^®S device is a safe and effective therapeutic option in patients presenting with acute symptomatic iliofemoral DVT.

Iliac vein stenting is a safe and effective treatment for iliac vein compression syndrome: A systematic review of Chinese data

OBJECTIVES

This study was a systematic review of available data from China, and our aim was to evaluate the safety and efficacy of stenting in iliac vein compression syndrome.

METHODS

We searched the PubMed, National Knowledge Infrastructure, Chongqing Weipu Information Company, and Cochrane Central Register for Controlled Trials databases, and key references.

RESULTS

Twelve studies were included (nine retrospective analyses, two retrospective case series studies, and one prospective cohort study) involving 2292 patients and 1897 stented limbs. The overall primary patency rates ranged from 81.8% to 100%. Studies showed significant improvements in patients' symptoms, and ulcer healing rates ranged from 71.4% to 100% in stented limbs. The incidence of severe complications ranged from 0 to 16.8%.

CONCLUSIONS

For Chinese patients with iliac vein compression syndrome, stenting provided significant efficacy regarding favorable patency rates, symptom relief, and complications. However, the quality of evidence to support the use of iliac vein stenting to treat iliac vein compression syndrome is currently weak, especially for Chinese patients.

Iatrogenic Iliac Vein Compression Syndrome Caused Because of Inappropriate Length and Positioning of Vascular Graft

Iliac vein compression syndrome (IVCS) can occasionally be iatrogenic; however, iatrogenic IVCS cases occurring because of inappropriate length and positioning of vascular grafts have not been reported. We present the case of an 80-year-old woman with iatrogenic IVCS resulting from kinked and overlapping limbs of a bifurcated abdominal vascular prosthesis for an abdominal aortic aneurysm. She complained of discomfort in her left leg immediately after aortic replacement. Venous stenting was effective for IVCS occurring because of compression of the vascular prosthesis. Iatrogenic IVCS occurred because of inappropriate length and positioning of the vascular graft and was considered a postoperative complication.

May-Thurner Syndrome: A Consideration for Deep Vein Thrombosis in Males

May–Thurner syndrome (MTS) is an underdiagnosed cause of lower limb deep vein thrombosis (DVT). The clinical prevalence of MTS-related DVT is likely underestimated, particularly in patients with other more recognisable risk factors. MTS is classically described in females between the age group of 20–50 years. In patients with acute iliofemoral thrombosis, medical treatment with anticoagulation alone has been associated with higher risk of postthrombotic syndrome (PTS) and lower iliofemoral patency rates, as compared to endovascular correction. We describe a case of MTS-related extensive iliofemoral DVT occurring in a middle age male who presented with acute onset of left lower limb swelling and pain, complicated by pulmonary embolism. Doppler compression ultrasonography of the left lower limb showed partial DVT extending from the left external iliac to the popliteal veins, and contrasted computed tomography (CT) of the thorax abdomen and pelvis established features of MTS, together with right pulmonary embolism. He was started on low molecular weight heparin (LMWH) and then underwent left lower limb AngioJet pharmacomechanical thrombolysis/thrombectomy, iliac vein stenting, and temporary inferior vena cava (IVC) filter insertion. After the procedure, the patient recovered and improved symptomatically with rapid resolution of this left lower limb swelling and pain. He was switched to an oral Factor Xa inhibitor and was subsequently discharged. After 1-month follow-up, he remained well with stent patency visualised on repeat ultrasound and underwent an uneventful elective IVC filter retrieval with subsequent plans for a 1-year follow-up.

A review into the management of May-Thurner syndrome in adolescents

OBJECTIVE

To investigate the presentation, etiology, management and outcomes of May-Thurner syndrome (MTS) in adolescents aged under 18.

METHODS

We searched electronic bibliographic databases to identify published reports of MTS in patients under 18 years of age. We conducted our review according to the PRISMA statement standards.

RESULTS

Ten studies encompassing 22 patients treated for MTS in adolescent cases were identified. The mean age of patients was 15 years (range, 10-18 years). Of the 22 patients, 12 (55%) were confirmed to have proximal deep vein thrombosis as the primary indication for intervention. Treatment methods included catheter-directed thrombolysis and iliac vein stenting (41%), pharmacomechanical thrombolysis and iliac vein stenting (18%), iliac vein stenting alone (27%), open surgery (14%), catheter-directed thrombolysis (5%), and anticoagulation alone (5%). Complications were infrequent. All studies reported subjective improvements in clinical symptoms with only two studies using validate outcome measures. In total, 9 of 22 patients (41%) had addition risk factors that may precipitate thrombosis.

CONCLUSIONS

As in adults, the most common form of treatment seen in the literature is a combination of catheter direct thrombolysis, followed by iliac vein stenting with subsequent anticoagulation. Complications from interventions were low. It is unclear how these interventions affect symptomology and the long-term sequalae associated endovascular surgery and stenting in adolescents. Further research is needed in well-designed studies with adequate follow-up.

Deep vein thrombosis due to May-Thurner syndrome: a case report

Background

May-Thurner syndrome (MTS) or Cockett’s syndrome is a rare clinical syndrome, which refers to the compression of the left common iliac vein (LCIV) by right common iliac artery and vertebral body. Complications of MTS include deep vein thrombus formation and even life-threatening pulmonary embolism.

Case presentation

Here, we report the case of a 60-year-old female patient with a complaint of swelling in the left lower limb and pain for 5 days. Computed tomography angiography indicated MTS, and thrombus formation of left external iliac vein and femoral vein. The patient was diagnosed with deep venous thrombosis (DVT) and MTS. The patient underwent ascending venography from the lower extremity to inferior vena cava (IVC) and then to the pulmonary artery with IVC filter implantation, left iliac vein balloon plasty, and stent placement. The patient visited the hospital for the removal of IVC filter, 28 days after the operation. After the interventional therapy, the patient had no in-stent restenosis and had remission during the 2-year follow-up.

Conclusions

This case presents a successful management of MTS in presence of DVT. Although clinicians are rarely aware, the presence of unilateral lower limb swelling and thrombosis may be the manifestations of MTS.

Review of imaging and endovascular intervention of iliocaval venous compression syndrome

Iliocaval venous compression syndrome (ICS) is the extrinsic compression of the common iliac vein by the overlying iliac artery against the vertebra. Chronic compression can lead to venous stenosis and stasis, which manifests as chronic venous disease and treatment resistance. Therefore, early recognition of ICS and prompt treatment are essential. Clinical presentations of ICS can be ambiguous and diagnosis requires a high index of suspicion with the relevant imaging studies. The initial imaging test is typically a Duplex ultrasound for vessel assessment and pelvic ultrasound to exclude a compressive mass, which is followed by computed tomography (CT) or magnetic resonance (MR) venography. CT and MRI can identify the anatomical causes for venous compression. In patients with high clinical suspicion for ICS, negative findings on CT and MR venography would still warrant further investigations. Definitive diagnosis can be established using catheter-based venography complemented with intravascular ultrasonography but the nature of their invasiveness limits its utility as a routine imaging modality. In this review paper, we will discuss the evidence, utility and limitations of the existing imaging modalities and endovascular intervention used in the management of ICS.

May-Thurner Syndrome: A Forgotten Cause of Venous Thromboembolism

The annual incidence rates of venous thromboembolism are approximately 1 per 1,000 persons per year in adult population. Deep vein thrombosis (DVT) most frequently occurs in the setting of underlying illness, and anatomical abnormalities are rarely considered as an etiology for it. A well-described anatomical cause for DVT is “May-Thurner syndrome” (MTS), which occurs as a result of compression of the left common iliac vein by the overlying right common iliac artery. This syndrome most often affects young to middle-aged women. Pulmonary embolism (PE) occurs very rarely in these patients. Anticoagulation therapy alone is not enough in these patients. We report a case of 27-year-old male who had both left DVT and PE caused by MTS and was treated with endovascular management along with long-term anticoagulation.

A case of May-Thurner Syndrome: An old anomaly but, a new suggestion: A case report

May-Thurner syndrome (MTS) is an anatomical condition resulting in compression of the left common iliac vein between the right common iliac artery and the underlying spine. MTS is rarely diagnosed because diagnostic workup is seldom continued once the diagnosis of a deep vein thrombosis (DVT) has been established. Furthermore, patients with DVT generally have several well-known confounding risk factors. We report a 16-year-old girl with a history of left leg swelling who was incidentally diagnosed with MTS. We hope that our case report will create awareness of vascular abnormalities in sports medicine and suggest that routine venous Doppler ultrasound screening may help to detect MTS or associated anatomical prior to the formation of early thrombosis.

Rare presentation and endovascular treatment of multifocal iliac venous stenoses due to right sided May-Thurner Syndrome

May-Thurner Syndrome (MTS) is a well-recognized anatomical variant describing compression of the left common iliac vein and may manifest as lower extremity swelling, pain, ulceration, discoloration, and paresthesia. Right-sided MTS is documented in the literature, though exceedingly rare. Specifically, no current reports describe a multifocal stenoses of the right iliac vein due to anatomical variants associated with left sided IVC. We present a case involving a patient with this pathophysiology, radiographic/sonographic correlate imaging, and subsequent endovascular treatment.