Outcomes of endovascular intervention for May-Thurner syndrome

Efficacy of ultrasound in the evaluation of iliac vein stenting

Objectives: The current study evaluated the efficacy of iliac and IVC ultrasound alone for follow-up evaluation of iliac vein stents in patients with pelvic venous disorders or iliac occlusion from chronic deep vein thrombosis. Methods: A retrospective single site cohort study was conducted by evaluating the most recent 100 iliac vein and inferior vena cava ultrasounds in patients who had undergone iliac vein stenting. Inclusion criteria included a history of iliac vein stent placement. Exclusion criteria included patients under 18-years-old, duplicates of the same patient, and pregnancy at the time of ultrasound. The degree of visualization for color flow, gray scale, and phasicity were determined and classified into the following categories: complete, partial, or none. In addition, each chart was assessed for external compression, in-stent narrowing, and requirements for further imaging. Results: Of the 100 iliac vein and IVC ultrasounds assessed in this review, 99 of the ultrasounds were sufficient for evaluation during follow-up visits without requiring further investigation. Within this study cohort, the average follow-up time was 22 months. The average participant body mass index was 27.6. One iliac vein and IVC ultrasound was considered inadequate for follow-up evaluation and required further imaging. Conclusion: The use of iliac and IVC venous doppler ultrasound alone in the follow-up evaluation of iliac stent patency is effective and noninvasive and avoids unnecessary radiation exposure and cost.

Surgical anteriorization of the left common iliac vein results in improved venous outflow and quality of life for May-Thurner syndrome

May-Thurner syndrome or left iliac vein compression occurs when the left common iliac vein is compressed by the right common iliac artery, leading to venous outflow obstruction. This obstruction can cause venous hypertension, resulting in lower extremity swelling, discoloration, pelvic congestion, and venous ulcerations. The standard surgical treatment of May-Thurner syndrome is endovascular venous stent placement. In a small, single-center sample, surgical anteriorization of the left common iliac vein was used to treat symptomatic left common iliac vein compression in younger patients, alleviating their symptoms, and can be considered an alternative treatment.

An Evaluation of the Duration of Oral Anticoagulant Use Among Patients Undergoing Endovascular Treatment of Nonthrombotic Iliac Vein Lesions

BACKGROUND

This study aimed to compare clinical outcomes associated with the duration of postoperative direct oral anticoagulant (DOACs) therapy in patients with nonthrombotic iliac vein lesions.

METHODS

We retrospectively analyzed 176 consecutive patients who underwent stenting for nonthrombotic iliac vein lesions between March 2018 and December 2021. In total, 99 and 77 patients were discharged on a 3-month and >3-month regimen of DOAC therapy, respectively. The primary cumulative endpoint was a composite of thrombotic complications, bleeding complications, primary patency, primary-assisted patency, and secondary patency within 1 year.

RESULTS

Patients undergoing 3-month and >3-month DOAC therapy were similar in age, sex, lesion site, symptoms, and average stent diameter and length. Upon multivariate analysis, the primary cumulative endpoint did not differ between the 2 groups (hazard ratio [HR]: 1.18; 95% confidence interval [CI]: 0.42-3.30; P = 0.76). Moreover, the primary patency at 1 year did not differ between the groups (HR: 1.50; 95% CI: 0.14-16.54; P = 0.74). Furthermore, there were no discernible differences in the secondary endpoints of bleeding complications (HR: 0.66; 95% CI: 0.22-1.96; P = 0.45) or thrombotic complications (HR: 1.79; 95% CI: 0.55-5.80; P = 0.34) between the groups.

CONCLUSIONS

The 3-month regimen of DOAC therapy showed a similar risk of postoperative thrombosis and bleeding when compared to longer DOAC therapy durations over the course of 1 year following endovascular intervention. This could be a preferred option for patients with a higher estimated bleeding risk after venous stenting.

Left Common Iliac Vein Stenting in a Case of Postural Orthostatic Tachycardia Syndrome/Pelvic Pain Overlap

Postural orthostatic tachycardia syndrome (POTS) is mainly characterized by orthostatic intolerance and positional tachycardia although it frequently involves a myriad of non-specific symptoms that seem to overlap with existing medical conditions. Recent efforts have been made to further classify subtypes of POTS and associated conditions to better delineate underlying pathophysiology in an effort to guide diagnosis and tailor treatment. Here, we present a 22-year-old female with debilitating symptoms of POTS who reported pelvic pain on review of systems and underwent vascular ultrasound of the inferior vena cava, iliac veins, and bilateral lower extremities which revealed the characteristic left common iliac vein compression of May-Thurner syndrome prompting venous stenting which provided systemic symptomatic relief.

Clinical Outcomes at 3 Years After Stenting for Thrombotic and Non-thrombotic Iliac Vein Compression Syndrome Patients

Iliac vein stenting for the treatment of iliac vein compression syndrome (IVCS) has been gradually developed. This article investigated the long-term patency and improvement of clinical symptoms after endovascular stenting for iliac vein obstruction patients. From 2020 to 2022, 83 patients at a single institution with IVCS underwent venous stent implantation and were divided into two groups: non-thrombotic IVCS (n = 55) and thrombotic IVCS (n = 28). The main stent-related outcomes include technical success, long-term patency, and thrombotic events. The technical success rate of all stent implantation was 100%. The mean length of hospital stay and cost were higher in the thrombotic IVCS group than in the non-thrombotic ICVS group, as well as the length of diseased vessel segment and the number of stents implanted were higher than in the control non-thrombotic group. The 1-, 2-, and 3-year patency rates were 85.4%, 80% and 66.7% in the thrombosis group, which were lower than 93.6%, 88.7%, and 87.5% in the control group (P = .0135, hazard ratio = 2.644). In addition, patients in both groups had a foreign body sensation after stent implantation, which resolved spontaneously within 1 year after surgery. Overall, there were statistically significant differences in long-term patency rate outcome between patients with thrombotic and non-thrombotic IVCS, the 1-, 2-, and 3-year patency rates in non-thrombotic IVCS patients were higher than those in thrombotic IVCS patients.

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.

The Clinical Problem of Pelvic Venous Disorders

Pelvic venous disorders are inter-related pathologic conditions caused by reflux and obstruction in the pelvic veins. It can present a spectrum of clinical features based on the route of transmission of venous hypertension to either distal or caudal venous reservoirs. Imaging can help to visualize pelvic vascular and visceral structures to rule out other gynecologic, gastrointestinal, and urologic diseases. Endovascular treatment, owing to its low invasive nature and high success rate, has become the mainstay in the management of pelvic venous disorders. This article reviews the pathophysiology, clinical presentations, and diagnostic and therapeutic approaches to pelvic venous disorders.

Clinical outcomes of AngioJet rheolytic thrombectomy in the treatment of May-Thurner syndrome-related deep venous thrombosis

Objective

May–Thurner syndrome (MTS) is an anatomic stenotic variation associated with deep vein thrombosis (DVT) of the left leg. The classical DVT treatment strategy is medical treatment without thrombus removal. This study was performed to assess the clinical outcomes of the combination of AngioJet™ rheolytic thrombectomy and stenting for treatment of MTS-related DVT.

Methods

We conducted a retrospective cohort study of patients treated for MTS-related DVT from January 2017 to June 2020 at a single institution.

Results

Fourteen patients (nine women) underwent AngioJet™ rheolytic thrombectomy for MTS-related DVT during the study period. The median DVT onset time was 8 days (interquartile range (IQR), 3–21 days). The median procedure time was 130 minutes (IQR, 91–189 minutes), and the median hospital stay was 7 days (IQR, 5–26 days). One patient had a residual thrombus and occluded iliac stent and underwent adjuvant catheter-directed thrombolysis for revascularization. The primary patency rate for the iliac stent was 92.9% at 12 months.

Conclusion

Concomitant AngioJet™ rheolytic thrombectomy and stenting of MTS-induced lesions may be beneficial for patients with MTS-related DVT.

Intravascular ultrasound for endovascular precision in pediatrics

Intravascular ultrasound (IVUS) is used as a diagnostic adjunct to angiography and has become a valuable diagnostic and interventional tool with a well-documented safety profile. The American College of Cardiology and the European Society of Cardiology have published guidelines regarding the use of IVUS in the setting of percutaneous coronary intervention. IVUS has gained popularity in the interventional radiology (IR) community in recent years; however, there are no consensus guidelines for utilization. Furthermore, IVUS remains an infrequently used modality in pediatric IR, likely because of unfamiliarity with the equipment and techniques, as well as concerns over the compatibility of these instruments with pediatric anatomy. IVUS can be safely used as a helpful and sometimes necessary tool for pediatric interventions in appropriately selected patients. The utility of IVUS for reducing both fluoroscopy time and contrast agent volume makes it particularly valuable in pediatric practice. This article presents an overview of both the rotational and phased-array IVUS types and an in-depth discussion on the most common applications of these techniques in the pediatric setting across multiple procedure categories.

Current Status and Prospect of Stent Placement for May-Thurner Syndrome

Stent implantation has been proven to be safe and has become the first-line intervention for May-Thurner syndrome (MTS), with satisfactory mid-term patency rates and clinical outcomes. Recent research has demonstrated that catheter-directed thrombolysis is the preferred strategy when MTS is combined with deep vein thrombosis after self-expanding stent placement. However, the stent used for the venous system was developed based on the experience obtained in the treatment of arterial disease. Consequently, relatively common corresponding complications may come along later, which include stent displacement, deformation, and obstruction. Different measures such as adopting a stent with a larger diameter, improving stent flexibility, and increasing stent strength have been employed in order to prevent these complications. The ideal venous stent is presently being evaluated and will be introduced in detail in this review.

A Systematic Review and Meta-Analysis of 12-Month Patency After Intervention for Iliofemoral Obstruction Using Dedicated or Non-Dedicated Venous Stents

BACKGROUND

Endovascular stenting of the deep venous system has been proposed as a method to treat patients with symptomatic iliofemoral outflow obstruction. The purpose of this systematic review and meta-analysis was to compare the effectiveness of this treatment at 1-year following the development of dedicated venous stents.

METHOD AND RESULTS

We searched MEDLINE and EMBASE for studies evaluating the effectiveness of venous stent placement. Data were extracted by disease pathogenesis: non-thrombotic iliac vein lesions (NIVL), acute thrombotic (DVT), or post-thrombotic syndrome (PTS). Main outcomes included technical success, stent patency at 1 year and symptom relief. A total of 49 studies reporting outcomes in 5154 patients (NIVL, 1431; DVT, 950; PTS, 2773) were included in the meta-analysis. Technical success rates were comparable among groups (97%-100%). There were no periprocedural deaths. Minor bleeding was reported in up to 5% of patients and major bleeding in 0.5% upon intervention. Transient back pain was noted in 55% of PTS patients following intervention. There was significant heterogeneity between studies reporting outcomes in PTS patients. Primary and cumulative patency at 1 year was: NIVL-96% and 100%; DVT-91% and 97%; PTS (stents above the ligament)-77% and 94%, and; PTS (stents across the ligament)-78% and 94%. There were insufficient data to compare patency outcomes of dedicated and nondedicated venous stents in patients with acute DVT. In NIVL and PTS patients, stent patency was comparable at 1 year. There was inconsistency in the use of validated tools for the measurement of symptoms before and after intervention. When reported, venous claudication, improved in 83% of PTS patients and 90% of NIVL patients, and ulcer healing occurred in 80% of PTS patients and 32% of NIVL patients.

CONCLUSIONS

The first generation of dedicated venous stents perform comparably in terms of patency and clinical outcomes to non-dedicated technologies at 1 year for the treatment of patients with NIVL and PTS. However, significant heterogeneity exists between studies and standardized criteria are urgently needed to report outcomes in patients undergoing deep venous stenting.

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

Reduced External Iliac Venous Blood Flow Rate Is Associated with Asymptomatic Compression of the Common Iliac Veins

Background and Objectives: Compression of the common iliac veins (CIV) is not always associated with lower extremity symptoms. This study analyzed this issue from the perspective of patient venous blood flow changes using quantitative flow magnetic resonance imaging. Materials and Methods: After we excluded patients with active deep vein thrombosis, the mean flux (MF) and mean velocity (MV) of the popliteal vein, femoral vein, and external iliac vein (EIV) were compared between the left and right sides. Results: Overall, 26 of the patients had unilateral CIV compression, of which 16 patients had symptoms. No significant differences were noted in the MF or MV of the veins between the two sides. However, for the 10 patients without symptoms, the EIV MF of the compression side was significantly lower than the EIV MF of the non-compression side (p = 0.04). The receiver operating characteristic curve and chi-squared analyses showed that when the percentage difference of EIV MF between the compression and non-compression sides was ≤-18.5%, the relative risk of associated lower extremity symptoms was 0.44 (p = 0.016). Conclusions: If a person has compression of the CIV, a decrease in EIV blood flow rate on the compression side reduces the rate of symptom occurrence.

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.

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.

Contemporary treatment of May-Thurner Syndrome

Compression of the left common iliac vein by the overlying right common iliac artery is a benign anatomic abnormality in most individuals. However, in patients with significant vein compression, outflow obstruction and chronic intraluminal venous damage may lead to May-Thurner Syndrome. This syndrome commonly manifests as unilateral left leg swelling or acute iliofemoral deep venous thrombosis. In addition to clinical findings, diagnosis is made with ultrasound, computed tomography venography, or magnetic resonance venography. The extent of compression of the iliac vein is best determined by venography with intravascular ultrasound. Symptoms and hemodynamic significance of the compression guides the ideal treatment approach. Iliocaval stenting has become the standard treatment for this condition and has promising patency rates and clinical outcomes. This review paper provides an overview of pathophysiology, and utility and limitations of the existing diagnostic modalities and treatment options in the management of May-Thurner Syndrome.

Endovascular and medical therapy of May-Thurner syndrome: Case series and scoping literature review

INTRODUCTION

May-Thurner syndrome has been recognized as a cause of chronic venous insufficiency and a trigger for venous thromboembolism. There is no consensus about the definition, diagnosis, and therapeutic approach. We are aiming to describe its characteristics and a scoping literature review.

METHODS

A retrospective review of patients with May-Thurner syndrome from March 2010 to May 2018 and scoping literature review were made.

RESULTS

Seven patients were identified. All patients were female with a median age of 36 (20-60) years. The median time from the first symptom to diagnosis was 3.41 (0.01-9) years. The primary clinical presentation was post-thrombotic syndrome (4 patients). Six patients had at least one risk factor for deep venous thrombosis. All patients underwent angioplasty with stent; patients with acute deep venous thrombosis, furthermore mechanic thrombectomy with or without catheter-directed thrombolysis were done. There were three complications (one patient, lymphedema, and two venous stent thrombosis). Scoping review results were descriptively summarized.

CONCLUSION

May-Thurner syndrome has a varied spectrum of clinical presentation, and clinical awareness is paramount for diagnosis. Its principal complication is the post-thrombotic syndrome, which is associated with high morbidity. There is no consensus on the antithrombotic treatment approach.

Transabdominal duplex ultrasound and intravascular ultrasound planimetry measures of common iliac vein stenosis are significantly correlated in a symptomatic population

OBJECTIVE

The objectives of the present study were to determine the validity of transabdominal duplex ultrasound (TAUS) against the reference standard of intravascular ultrasound (IVUS) examinations for the detection of iliac vein obstruction (IVO).

METHODS

We analyzed the data from patients at a private vascular laboratory who had undergone IVUS investigation with an intention to treat because of symptoms of chronic venous insufficiency and a high suspicion of IVO. These patients had also previously undergone a TAUS examination at the same location. The TAUS and IVUS planimetry measures of the left common iliac vein (CIV) were correlated. These included the TAUS-measured minimum and maximum diameter and the percentage of stenosis with the IVUS-measured minimum and maximum diameter and area and the percentage of stenosis.

RESULTS

The TAUS and IVUS data from 47 patients (83% female; age, 49.3 ± 17.3 years; 64% obese) were included in the analyses. We found 89% agreement between the TAUS and IVUS findings regarding the identification of left CIV stenosis of ≥50%. The TAUS data had a positive predictive value of 95.5%. The TAUS measures of the minimum diameter and percentage of stenosis correlated significantly with the IVUS measures of the minimum diameter, minimum area, and cross-sectional area of the percentage of stenosis. The strongest correlations were between the TAUS-measured minimum diameter and IVUS-measured minimum area and percentage of the area of stenosis according to the literature-derived value. The TAUS-measured vein diameter of 8 mm equated to an IVUS cross-sectional area of 94.2 mm² (53% stenosis), and an IVUS cross-sectional area of 50% of stenosis equated to a TAUS diameter of 8.56 mm.

CONCLUSIONS

The findings from the present study support the validity of TAUS evaluation as a workup diagnostic tool for the detection of IVO. Our findings also support the use of TAUS planimetry-in particular, the CIV diameter of ≤8 mm as a threshold value-to indicate clinically relevant stenosis and trigger an IVUS investigation with an intention to treat, because this correlated with a cross-sectional area stenosis of ≥50%, as determined by IVUS examination.

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.

Percutaneous endovenous intervention without vena cava filter for acute proximal deep vein thrombosis secondary to iliac vein compression syndrome: preliminary outcomes

The aim is to report the preliminary outcomes of percutaneous endovenous intervention (PEVI) for acute proximal deep vein thrombosis (DVT) secondary to iliac vein compression syndrome (IVCS) without inferior vena cava filter (IVCF) placement. Acute DVT patients who underwent PEVI without IVCF were analyzed retrospectively. PEVI consisted of catheter-directed thrombolysis, manual aspiration thrombectomy, balloon angioplasty and stenting. CT was used to evaluate the left common iliac vein (LCIV). Sixty-two consecutive patients (17 men and 45 women, mean age, 59.4 ± 15.2 years) were enrolled. The compression percentage of the LCIV ranged from 51.7% to 95.2% (median 83.2%). Iliac DVT was present in 7 patients; iliofemoral, in 30 patients; and iliofemoropopliteal, in 25 patients. Complete technical success and clinical improvement were obtained in all subjects without the occurrence of symptomatic pulmonary embolism (PE). Five patients experienced recurrent thrombosis. The primary patency rates at 12 and 24 months were 93.8% and 91.4%, respectively, which remained stable at 36, 48 and 60 months. The secondary patency rates at 12 and 24 months were 95.7% and 93.3%, respectively, and there was no change at 60 months. Although limited, our preliminary results suggested that PEVI without IVCF placement seemed to be safe and effective for acute proximal DVT secondary to IVCS without inferior vena cava thrombosis or symptomatic PE.

Endovascular versus medical treatment of venous compression syndrome of the iliac vein - a systematic review

The treatment of non-thrombotic iliac vein lesions (NIVL) remains debatable with many advocating conservative treatments, whilst others offering venous stenting. The objective of this review was to systematically assess the treatment options for symptomatic iliac vein compression syndrome (IVCS) in patients without evidence of thrombotic disease at the time of diagnosis. An online search of published literature looking for randomised controlled trials and observational studies that evaluated the treatment for symptomatic NIVL was performed. Nine studies were included with a total 953 patients of which 782 patients had NIVL. Patency rates ranged between 94.8%-100% in the first month, 88.2%-94.1% in six months and 73.4%-98% in 12 months, in patients with NIVL post stenting. Longer follow-up of up to 5 years shows promising patency rates of 94% in patients with IVCS. Patients with IVCS are likely to benefit from a combination of endovenous treatment at the time of diagnosis including stent placement to maintain lumen patency and prevent recurrent deep venpus thrombosis and/or postthrombotic syndrome.

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.

Imaging findings of pelvic venous insufficiency in patients with postural orthostatic tachycardia syndrome

OBJECTIVES

Some patients with postural orthostatic tachycardia syndrome (POTS) demonstrate improved dysautonomic symptoms following treatment for pelvic venous insufficiency (PVI). This study assessed the prevalence of significant left common iliac vein (LCIV) compression in POTS patients.

METHODS

Radiologists retrospectively reviewed CT images of pelvic veins for 216 women (191 with POTS and 25 age-comparable controls).Quantitative vascular analysis identified percent-diameter compression of the LCIV by the right common iliac artery. Significant LCIV compression was defined as >50%.

RESULTS

Significant LCIV compression was found in 69% (131/191) of females with POTS versus 40% (10/25) in controls. The hypothesis that venous compression and presence of POTS are independent was rejected (p = .005).

CONCLUSIONS

Significant LCIV compression was noted in a majority of female POTS patients, suggesting that incidence of iliac venous obstruction may be higher than the general population. Patients with POTS and symptoms of PVI may benefit from assessment for venous outflow obstruction.

May-Thurner Syndrome: A Neglected Cause of Unilateral Leg Swelling

May-Thurner syndrome (MTS) is a clinical condition characterized by the compression of the left iliac vein by the right iliac artery. This condition predisposes the patient to deep venous thrombosis (DVT). We present the case of a 30-year-old female who arrived at the emergency department of our facility with progressive left leg swelling for four weeks, with low-risk probability for DVT. Examination revealed left leg swelling with pitting edema extending up to the knee. Her calf muscle was tender to palpation. Dorsalis pedis, anterior tibial, and posterior tibial pulsations were fairly palpable due to the edema; however, the rest of her pulsations were appropriately felt. Therefore, the provisional diagnosis of possible DVT was made, and further investigations were requested. We present this case intending to highlight the clinical presentation of May-Thurner syndrome, its diagnosis, and treatment.

Giant subserosal myoma causing deep venous thrombosis in a patient with pre-existing May-Thurner syndrome

One of the rare sequelae of large pelvic masses is direct compression of the inferior vena cava with formation of a deep venous thrombosis (DVT). Although uncommon, multiple cases of thrombosis secondary to pelvic mass compression of the venous system have been reported in the literature. However, our patient showed a disproportionate degree of thrombus and subsequent postthrombotic stricture/stenosis limited to the left iliofemoral system, sparing the right side. These findings make it exceedingly likely that she had some degree of pre-existing May-Thurner syndrome. The superimposed nature of these 2 rare causes of DVT make this presentation remarkably unique. Our case illustrates the advances in endovascular techniques and their application toward DVT treatment for even the most complicated and unique cases.

May-Thurner syndrome: History of understanding and need for defining population prevalence

Patients with May-Thurner syndrome (MTS) are at elevated risk of developing an extensive left iliofemoral deep vein thrombosis (DVT; localized blood clot) due to an anatomical variant where the right common iliac artery compresses the left common iliac vein against the lumbar spine. While MTS was initially presumed to be rare when it was first anatomically defined in 1957, case reports of this syndrome have recently become more frequent, perhaps due to improved imaging techniques allowing for enhanced visualization of the iliac veins. Still, the population burden of this condition is unknown, and there is speculation it may be higher than generally perceived. In the present review, we (a) review history of how MTS became recognized, (b) describe practical challenges of studying MTS in population-based settings due to the specialized imaging required for diagnosis, (c) discuss why the contribution of MTS to DVT may be underestimated, (d) describe uncertainty regarding the degree of venous compression which leads to DVT, and (e) outline future research needs. Our goal is to raise awareness of MTS and spark additional research into the epidemiology of this condition, which may be an underappreciated causative venous thromboembolism risk factor.

Intravascular Ultrasound for the Peripheral Vasculature-Current Applications and New Horizons

Intravascular ultrasound (IVUS) is a proven and rapidly developing imaging modality that can be used for a multitude of both diagnostic and interventional purposes. By allowing for superior intraluminal characterization, compared with angiography, IVUS has emerged as a technically valuable tool in interventional procedures such as transjugular intrahepatic portosystemic shunt/direct intrahepatic portosystemic shunt, venous interventions (May Thurner stenting, inferior vena cava filter placement, recanalization in the setting of chronic venous thrombosis/insufficiency), percutaneous fenestration in the setting of aortic dissection and angioplasty. Additional applications evaluating coronary arteries and plaque morphology have been described, but are outside the scope of this review. In addition to IVUS's merit as a pre- and intra-procedural guidance modality, there are also several advantages compared to the gold standard of angiography which include decreased need for iodinated contrast, decreased radiation exposure and decreased procedural times in certain cases. With current research, such as that aimed at supraharmonic imaging, further improvements in imaging depth, resolution and contrast to noise ratio are on the horizon.

Iliac Vein Stenting for Chronic Proximal Venous Outflow Obstruction in a Predominantly Asian-American Cohort

BACKGROUND

We investigated the outcome of vein stenting placement for chronic proximal venous outflow obstruction (PVOO) in a predominantly Asian-American cohort to improve patient selection, enhance technical approach, and better define quality measurements of this emerging vascular intervention.

METHODS

A total of 462 consecutive patients, 73% Asian American (n = 336), who underwent iliac vein stenting for chronic PVOO from October 2013 to July 2016 were reviewed. Postoperative outcomes at five follow-up visits were assessed. Wilcoxon-Mann-Whitney and Kruskal-Wallis tests were run for demographic and operative variables. Ordered logistic regressions were run for the outcome at each time point, and Chi-squared tests as well as Fisher's exact tests were used for categorical variables.

RESULTS

Follow-up was maintained in 90% of patients, with a mean follow-up time of 695 days. Asian-American patients were more likely to present with varicose veins (77.4% vs. 54.8%, P < 0.001), and non-Asian patients were more likely to present with active ulceration (26.2% vs. 5.1%, P < 0.001). Asian-American patients were more likely to have bilateral stents placed (61.6% vs. 50%, P = 0.026) and were less likely to have reinterventions (11.3% vs. 27.8%, P < 0.001), a history of deep vein thrombosis (8.3% vs. 29.4%, P < 0.001), or intraoperative findings of chronic postphlebitic changes (17.6% vs. 33.3%, P < 0.001). Kruskal-Wallis tests were significant for improvement in patients of all the Clinical, Etiology, Anatomy, Pathophysiology classes at 30 days (P = 0.041), 90 days (P = 0.045), 6 months (P = 0.041), and 1 year (P < 0.01). The Asian-American population had improved but comparatively lower follow-up scores at the 30-day mark (48% significantly improved or better vs. 63%, P = 0.008) but higher follow-up scores at the >1 year mark (80% significantly improved or better vs. 59%, P < 0.001).

CONCLUSIONS

Asian-American patients undergoing vein stent placement for chronic PVOO had comparatively worse outcomes than non-Asian patients at 30 days and better outcomes after one year. These patient groups had different outcomes postoperatively and outcomes which evolve differently over time.

Intrarachidial Misplacement of a Venous Stent for Iliofemoral Deep Vein Thrombosis

Introduction

Complications due to venous thrombectomy and iliofemoral stenting in a patient with May–Thurner syndrome are reported.

Report

The patient presented with a third episode of deep vein thrombosis (DVT). A computed tomography (CT) scan confirmed the clinical suspicion of left iliofemoral vein thrombosis. After thrombectomy and stenting, the patient complained of left foot paralysis. CT showed the misplaced stent to be in the intrarachidial space. Surgical removal of the stent and new endovascular stenting resulted in complete recovery.

Discussion

This is the first description of this kind of complication after stenting of the left iliofemoral vein. Peri-operative Xray appeared to confirm correct placement of the stent via bilateral femoral venous access. Is a profile control image necessary in patients with an important collateral venous network including large veins?

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Description of misplacement of an iliofemoral stent in the intrarachidial space.

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Large collateral veins and superimposition of guidewires led to misplacement.

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Need for double checking by radiological profile images.

Diagnosis and management of right external iliac vein "sandwich": A rare cause of iliofemoral deep venous thrombosis

Several anatomic abnormalities predispose patients to iliofemoral deep venous thrombosis, the most common of which is compression of the left iliac vein between the right common iliac artery and lumbar vertebrae, or May-Thurner syndrome. Other areas of venous compression can occur but are rare. This case report describes the presentation, diagnosis, and management of a patient with compression of the right iliac vein "sandwiched" between the right internal and external iliac arteries. After treatment, the patient demonstrated significant improvement in symptoms.

Endovascular Management of May-Thurner Syndrome in a Patient with Left-Sided Superior Vena Cava: A Case Report

Patient: Male, 23

Final Diagnosis: May-Thurner syndrome

Symptoms: Claudication

Medication: —

Clinical Procedure: Venous stenting

Specialty: Interventional Radiology • Vascular Surgery

Endovascular intervention for iliac vein thrombosis after simultaneous kidney-pancreas transplant

May–Thurner syndrome (MTS) is an anatomic variant where the overlying right common iliac artery compresses and chronically obstructs the left common iliac vein, leading to thrombosis. Interventions for symptomatic MTS include endovascular thrombectomy and stenting. Occluding venous thrombus can be fatal to transplanted allografts. No guidelines exist for patients with MTS after simultaneous kidney-pancreas transplant. A 57-year-old female with ESRD and diabetes mellitus underwent a kidney-pancreas transplant. Post-operative imaging revealed a compressed left CIV with an occlusive thrombus threatening the renal graft. Thrombectomy with stent placement was performed, maintaining patency of both allograft venous outflows. Post-intervention the patient has demonstrated preserved kidney and pancreas allograft function through 1 year of follow-up. Interventions for MTS in patients after transplant are challenging given the complex allograft vascular reconstruction. We present a case which demonstrates that angiographic interventions for MTS can be safely performed after simultaneous kidney-pancreas transplant.

Slippery Stents: A Case Report and Review of the Literature Describing Patients with May-Thurner Syndrome That Experienced Stent Migration

Endovascular stent placement is an effective treatment for relieving chronic venous obstruction in patients with May-Thurner Syndrome (MTS) with or without the presence of thrombotic lesions. Stent migration is a rare but potentially life-threatening complication of endovascular stenting. Herein, we describe a case of stent migration from the left common iliac vein into the right heart, requiring open-heart surgery. We also completed a literature review of MTS patients with stent migration in hopes of raising awareness of this rare and life-threatening complication.

Long-term follow-up of the stenting across the iliocaval confluence in patients with iliac venous lesions

Stent implantation is the common treatment method for iliac vein (IV) occlusion. IV stents usually enter into the inferior vena cava (IVC) to partially or completely cover the contralateral IV, but it is still uncertain whether this can increase the risk of thrombosis in the contralateral IV. The purpose of this study was to investigate the effect of the stent position on the bilateral IVs patency. A total of 261 patients with symptomatic IV lesions, including 177 patients with non-thrombotic iliac vein lesions (NIVLs) and 84 patients with thrombotic iliac vein lesions (TIVLs), were implanted with IV stents between July 2007 and June 2017. The data of these patients were retrospectively studied. The follow-up time was 6-114 months, and the median time was 62 months. A total of 183 cases had stenting into the IVC for more than 5 mm. The incidence of thrombosis in the contralateral IV was only 0.55% (1/183). A total of 17 short- and long-term cumulative cases had ipsilateral thrombosis on the stent side. There was no significant difference between the incidence of patients (8.79%, 7/78) with stenting into the IVC for less than 5 mm and those with more than 5 mm (5.46%, 10/183, P = 0.287). However, in the TIVLs group, the incidence of ipsilateral thrombosis between stenting positions less than 5 mm (29.6%, 8/27) and those more than 5 mm (8.77%, 5/57) was significantly different (P = 0.022). Stent implantation for NIVLs had an excellent long-term patency rate; the primary patency rate and the assisted primary patency rate were 97.7% and 100%, respectively. The entry of IV stents into the IVC was safe and had a very low incidence of thrombosis in the contralateral vein. Stenting less into the IVC increased the incidence of thrombosis in the ipsilateral vein, especially among thrombotic cases. Treatment of NIVLs using stent implantation had a better long-term patency rate. This principle plays an important guiding role in the endovascular therapy of IV lesions.

Mid-and long-term efficacy of endovascular-based procedures for Cockett syndrome

To investigate the mid- and long-term results of endovascular-based procedures for Cockett syndrome. The clinical data of 412 patients with Cockett syndrome treated between January 2003 and September 2017 were retrospectively analyzed. In these patients, 231 cases were acute left iliac femoral vein thrombosis (group A), and 181 cases were chronic venous insufficiency (group B), and different endovascular procedures and/or hybrid procedures were performed. In group A, the technique success rate was 100% (231/231); the left iliac vein in 5 patients showed no stenosis or occlusion, and the incidence of pathological changes in the left iliac vein was 97.8% (226/231); a total of 182 stents were implanted. In group B, the technique success rate was 99.4% (180/181); the average pressure difference between the proximal and distal portion of the pathological left iliac veins decreased from preoperative (18 ± 4.45) cmH2O to postoperative (4 ± 3.02) cmH2O (P < 0.01); 89 patients, complicated with valvular incompetence in the left superficial femoral vein, underwent a second-stage femoral valve repair. Follow-up ranged from 3 months to 8 years, with an average of 35.6 months, and intrastent thrombosis occurred in 15 cases of group A and in 2 cases of group B. Endovascular-based procedures offer favorable mid- and long-term results in treatment of Cockett syndrome, which in combination with Fogarty catheter thrombectomy or catheter-directed thrombolysis is a beneficial complementary treatment for patients with acute iliac femoral vein thrombosis.

Late-Onset Nonthrombotic Left Common Iliac Vein Compression Secondary to Degenerative Lumbar Disc: A Case Report of May-Thurner Variant

May-Thurner syndrome (MTS) refers to venous outflow obstruction caused by extrinsic compression of the left common iliac vein (LCIV) by the overlying pulsatile right common iliac artery against lumbar vertebrae. The classic clinical presentation is acute unilateral left leg painful swelling due to deep venous thrombosis in a young woman in the second or third decade of life. We present a case of a 66-year-old woman who presented with late-onset left leg swelling caused by nonthrombotic venous hypertension due to degenerative lumbar disc bulge leading to LCIV compression against the left common iliac artery which was confirmed by computed tomography and intravascular ultrasound. Our case highlights the importance of high index of suspicion for MTS in elderly patients with unilateral leg swelling and the importance of multimodality imaging for understanding the mechanism and appropriate treatment of MTS.

May-Thurner Syndrome: A Rare Cause of Deep Venous Thrombosis

May-Thurner syndrome (MTS) is a medical condition where the left iliac vein is compressed by the right iliac artery, which in turn predisposes patients to deep venous thrombosis (DVT). We present a case of a 67-year-old female who had pain and swelling of the left leg. Ultrasound of the deep veins of the leg revealed DVT of the distal external iliac vein. She was treated with catheter-directed thrombolysis and stent placement. Finally, she was discharged on long-term anticoagulation with warfarin. The purpose of presenting this case is to highlight the clinical presentation, diagnosis, and treatment of MTS.

A systematic review on the use of deep venous stenting for acute venous thrombosis of the lower limb

OBJECTIVES

The aim is to evaluate venous stent patency, the development of post-thrombotic syndrome, recurrence, quality of life and the optimal post-procedural anticoagulation regimen in the treatment of iliofemoral deep venous thrombosis.

METHOD AND RESULTS

EMBASE and Medline databases were interrogated to identify studies in which acute deep venous thrombosis patients were stented. Twenty-seven studies and 542 patients were identified. Primary, assisted primary and secondary patency rates 12 months after stent placement ranged from 74 to 95, 90 to 95 and 84 to 100%, respectively. The observed post-thrombotic syndrome rate was 14.6%. The incidence of stent re-thrombosis was 8%. In 26% of studies, patients received additional antiplatelet therapy. Quality of life questionnaires employed in 11% of studies, demonstrating an improvement in the chronic venous insufficiency questionnaire (22.67 ± 3.01 versus 39.34 ± 6.66).

CONCLUSION

Venous stenting appears to be an effective adjunct to early thrombus removal; however, further studies are needed to identify optimal anticoagulant regimen and effect on quality of life.

May-Thurner: diagnosis and endovascular management

Common left iliac vein compression, otherwise known as May-Thurner (MT), is an anatomical risk factor for lower extremity deep vein thrombosis (DVT). MT refers to chronic compression of the left iliac vein against the lumbar spine by the overlying right common iliac artery. The compression may be asymptomatic. The syndrome is a clinical spectrum of physical findings and history plus the lesion. It is characterized by the varying degrees of venous hypertension. This can be non-thrombotic, combined with acute DVT or post-thrombotic. Traditionally, acute DVT was treated with standard anticoagulation and sometimes, thrombectomy. However these measures do not address the underlying culprit lesion of mechanical compression. Furthermore, if managed only with anticoagulation, patients with residual thrombus are at risk for developing recurrent DVT or post-thrombotic syndrome (PTS). Both retrospective and prospective studies have shown that endovascular management should be the preferred approach to dissolve proximal thrombus and to also treat the underlying compression with endovascular stent placement.

Iliac Vein Compression Syndrome (IVCS): An Under-Recognized Risk Factor for Left-Sided Deep Venous Thrombosis (DVT) in Old Hip Fracture Patients

BACKGROUND The aim of this study was to identify whether iliac vein compression syndrome (IVCS) is a risk factor for left-sided deep venous thrombosis (DVT) in hip fracture patients and the influence IVCS may have on the treatment of DVT. MATERIAL AND METHODS A retrospective study was carried out among 424 hip fracture patients admitted to our hospital from 2011 to 2016. Clinical data were analyzed, and all patients were classified into the DVT group and the non-DVT group based on plasmin D-Dimer concentration and results of Doppler ultrasound of the left lower limb. Also, a 50% intraluminal constriction of the left iliac vein in the venography image was considered as IVCS. Comparison of IVCS prevalence was made between the DVT group and the non-DVT group. Patients in the DVT group were further divided into the DVT+/IVCS+ group and the DVT+/IVCS- group to evaluate the influence IVCS may have on the treatment of DVT. RESULTS There were 204 patients in the DVT group and 220 patients in the non-DVT group. No statistically significant differences were found regarding the mean age, sex distribution, fracture type, and accompanying risk factors between the two groups. A total of 70 patients (34.3%) were diagnosed with IVCS in the DVT group, while confirmed IVCS was found in 52 patients (23.6%) in the non-DVT group (P=0.02). Postoperatively, the incidence of symptomatic DVT in the DVT+/IVCS+ group and the DVT+/IVCS- group was 30.0% and 11.9%, respectively (P=0.002). CONCLUSIONS IVCS is an under-recognized risk factor for left-sided DVT in hip fracture patients. What's more, anticoagulation alone is insufficient for the treatment of DVT when it is complicated with IVCS. More aggressive measures have to be taken to achieve a favorable outcome.

An Extensive Unprovoked Left Lower Extremity Deep Vein Thrombosis Secondary to an Anatomical Anomaly: A Case of May-Thurner Syndrome

May-Thurner syndrome (MTS) also known as Cockett’s syndrome is a rare condition responsible for 2%-3% of all cases of deep venous thrombosis (DVT). The thrombosis results from mechanical compression of the left common iliac vein against the body of the fifth lumbar vertebra by the right common iliac artery. Repetitive hyperplasia of the venous wall by compression results in spur formation that in turn causes venous flow obstruction and results in the DVT. Our case is a young female who had acute extensive proximal DVT due to MTS that was successfully managed using mechanical thrombectomy with a venous stent. MTS although a rare entity should be suspected especially in young patients with unilateral DVT with extensive clots especially on left lower extremity without any antecedent risk factors.