Iliac Vein Stenting Research Articles

PERFORMANCE TEST AND EXPERIMENTAL STUDY OF SPECIAL STENT FOR TREATMENT OF ILIAC VEIN STENOSIS

Objective: Animal experiments and clinical trials were carried out to evaluate the efficiency of a new stent for the treatment of iliac vein stenosis. Methods: The new iliac vein stent and the control stent were implanted, respectively, into the 12 experimental pigs. Digital Subtraction Angiography was done separately at the same day, 14th, 30th, 60th and 90th day after stent implantation to observe the stent deployment. One patient was implanted with a new iliac vein stent. Digital subtraction angiography (DSA) was done after the operation to calculate the lumen loss value and lumen loss rate of the stent and evaluate the performance of the new iliac vein stent at 12 months of follow-up. Results: The mechanical experiment and finite element analysis of the stent proved that the radial support force of the new stent is significantly better than that of the control stent. In animal experimental verification, both groups of stent were released satisfactorily during implantation. No obvious stent displacement was found at each time point. The patency rate of stents was 100%. Except for a small amount of old thrombosis in the stent in the control group, no other stents were found in that condition. The diameter of the stent lumen was retracted in different degrees in both groups after the operation, but no significant statistical difference was found in the comparison of the stent lumen loss rate at each relative inspection day. Conclusion: The new nickel-titanium alloy iliac vein stent has excellent radial support performance, which may be an ideal iliac vein stent.

Presentation patterns in women with pelvic venous disorders differ based on age of presentation.

The prevalence and presentation patterns in women with pelvic venous disorders (PeVD) secondary to pelvic venous insufficiency (PVI) at various ages are ill-defined. The purpose of this investigation was to determine if the types of symptoms, interventions, and treatment outcomes of women with PeVD varied with age progression. From January 2015 to December 2019, we retrospectively reviewed prospectively collected data on 1,280 women with PeVD from our electronic medical record at the Center for Vascular Medicine (CVM). Medical and surgical comorbidities, past medical history, presenting pelvic and lower extremity symptoms, Clinical, Etiology, Anatomy, Pathophysiology (CEAP) class, revised Venous Clinical Severity Score (rVCSS), visual analog pain score (VAS) and types of interventions were assessed. Patients were grouped into five categories based on age of initial presentation: 20-29, 30-39, 40-49, 50-59, and greater than or equal to 60. Patients were also subcategorized according to their course of treatment: Iliac venous stenting alone, ovarian vein embolization (OVE) alone, simultaneous iliac vein stenting and ovarian vein embolization, and staged iliac vein stenting and ovarian vein embolization. Differences in groups were analyzed utilizing chi square, analysis of variance and regression analysis with Graphpad Prism 8 (San Diego, CA) and SAS Studio 3.8 (Cary, NC) statistical software. From January 2015 through December 2019, 1,280 women were treated for PeVD. The average ages in each group were the following: 26.53 ± 2.90 (n = 57), 35.80 ± 2.84 (n = 238), 44.98 ± 2.78 (n = 345), 54.67 ± 2.90 (n = 324) and 68.39 ± 8.44 (n = 316) respectively. The prevalence of PVI by age group was 4.45%,18.59%, 26.95%, 25.31% and 24.70% respectively (p < 0.05). The prevalence of diabetes, hypertension, coronary artery disease (CAD) and hypercholesterolemia differed between age groups (p < 0.05). Significant differences in the prevalence of pelvic pain, dyspareunia, dysmenorrhea, vulvar varices, leg pain, leg edema, leg heaviness, restless legs, varicose veins, and leg ulcers were observed across treatment groups (p < 0.05). CEAP distribution differed by age with CEAP 0-2 decreasing with age, CEAP 3 progressively increasing with age and CEAP 4-6 predominantly observed in patients older than 50. Analysis of variance indicated that with each decile increase in age, the prevalence of leg symptoms increased (p < 0.05) with a reciprocal decrease in pelvic symptoms (p < 0.05). All intervention types were infrequent in twenty year old's. There was a linear increase in stenting with each decile increase in age. The prevalence of OVE was similar across all age groups. There was an overall improvement in VAS scores for all treatment and age groups. For patients in their 20 s, an initial improvement in VAS scores was observed with moderate recurrence of pain observed after three months. PeVD presents as a spectrum of signs and symptoms, with pelvic and leg symptoms being inversely related according to age. The prevalence of PeVD is lowest in patients in their twenties with differences in presentation observed with increasing age. Venous stenting progressively increases with each decile of age whereas the prevalence of OVE is similar regardless of age. There is overall improvement in symptoms post intervention, although women in their 20 s do not respond as well to intervention as women in other age groups. Future investigations will focus on determining which pelvic venous lesion is the predominant factor that needs correction to achieve maximal pain reduction.

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

Chronic proximal venous outflow obstruction (PVOO) presentation, treatment needs, and outcomes differ in Asian Americans compared with non-Asian patients. Study Summary: This was a large (N = 462) study of consecutive patients with PVOO that included 336 (73%) Asian Americans treated in a 3-year time span with a 90% follow-up during 695 days. Asian Americans were more likely to present with varicose veins rather than with ulceration and to have bilateral iliac venous stent placement and less likely to have had a deep venous thrombosis and any reinterventions. Follow-up outcome scores were worse at 30-days but improved at 1 year compared with non-Asians. This observational study of Asian Americans' presentation and response to treatment for PVOO is important, showing the effects of chronic venous insufficiency in a population. The literature has shown ethnic differences in the incidence and prevalence of venous thromboembolism in Asians, but this is the first study of which I am aware looking at iliac venous disease and interventions. More epidemiologic data are needed to understand interethnic disparities and possibly the relative roles of genetic and environmental factors.

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

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

Female Sex Is a Predictor of Lower Iliac Vein Stenting Patency Rates

Iliac vein stenting for thrombotic and nonthrombotic venous disease is being increasingly used as the safety, efficacy, and durability of these interventions increase. Female sex has been implicated as a predictor of failure in arterial endovascular interventions. We hypothesize that female sex could be predictive of patency rates of iliac vein stenting. Consecutive patients who underwent iliac vein stenting for thrombotic or nonthrombotic venous disease at our institution from 2007 until 2019 were identified and divided into groups based on sex. Operative notes, venograms, and the electronic health record were then queried to obtain operative details, comorbid conditions, postoperative outcomes, and stent patency. Study end point was long-term patency rate. The data were analyzed using χ2 test, logistic regression, and survival analysis as appropriate. In our retrospective analysis, 200 consecutive patients (231 limbs) were identified with a mean age of 49.49 ± 17.7 years and body mass index (BMI) of 31.6 ± 8.6 kg/m2. Of those, 100 limbs were of male patients and 131 were of female patients. Comparisons between the groups revealed no difference in age, BMI, or preoperative comorbidities. There was no difference in type of occlusion between male patients (60/100 [60%] acute occlusion, 25/100 [25%] chronic occlusion, 15/100 [15%] nonocclusive lesions) and female patients (78/131 [60%] acute occlusion, 32/131 [24%] chronic occlusion, 21/131 [16%] nonocclusive lesions; P = .976). The male cohort was more likely to present with leg ulceration (17% vs 4.6%; P = .002), and the female cohort was more likely to present with left-sided symptoms (71% vs 48%; P = .001). The male cohort had a higher rate of bilateral (38% vs 18.3%; P = .027), caval (48% vs 33.6%; P = .027), and infrainguinal (11% vs 6.9%; P = .02) stent extension. Female patients had a higher rate of left-sided stenting (71% vs 48%; P = .006). There was no difference in the median stent diameter used between the cohorts. Primary patency at 5 years was significantly higher for the male cohort (94.1% vs 74.4%; P = .01; Fig). After adjustment for age, BMI, current smoking, history of a hypercoagulable state, presenting side, and proximal/distal extension, female sex remained a predictor of loss of primary patency with a hazard ratio of 3.2 (P = .016). In this single-center retrospective analysis of iliocaval stenting, male patients were found to have better primary stent patency compared with female patients.

Antithrombotic therapy after iliac vein stenting

Stenting for iliac vein stenosis or compression has become a common therapeutic approach in recent years. The antithrombotic therapy after the stent deployment, however, reaches no consensus. Medications strategies and patients' prognoses differ in non-thrombotic, acute thrombotic and chronic thrombotic these three circumstances. Non-thrombotic patients usually possess satisfactory stent patency whatever antithrombotic therapy is used. Anticoagulant is the basic medication for acute thrombotic patients, benefits from additional antiplatelet drug remains to be clarified. In terms of chronic thrombotic patients, their prognoses are unsatisfactory under all antithrombotic therapies. In this review, we outlined the recent progress of antithrombotic therapy after iliac vein stenting, aiming to provide feasible medication plans for each circumstance.

Contralateral limb improvement after unilateral iliac vein stenting argues against simultaneous bilateral stenting

ObjectiveSymptoms of chronic venous insufficiency secondary to obstructive iliofemoral disease are often bilateral. The impact of iliofemoral stenting of the more symptomatic lower extremity on clinical outcomes in the less affected contralateral extremity is not clear. Such benefit, secondary to offloading of collaterals, may potentially be of the magnitude that the contralateral extremity does not require intervention. MethodsA retrospective review of contemporaneously entered electronic medical record data of 368 patients/limbs with initial unilateral iliocaval stents (240 left and 128 right) placed during a 3-year period from 2015 to 2017 was performed. Patients who underwent simultaneous bilateral stenting or had occlusive disease were excluded. Of the remainder, the impact of stenting on contralateral leg symptoms was evaluated by analyzing visual analog scale (VAS) pain score (1-10), grade of swelling (1-3), and Venous Clinical Severity Score (VCSS). The duration of any improvement and need for intervention on the contralateral side were also appraised. Kaplan-Meier analysis was used to assess stent patency after intervention, whereas paired t-tests were used to examine clinical outcomes. ResultsOf the 368 limbs that underwent stenting with a combination of a Wallstent (Boston Scientific, Marlborough, Mass) with a Z stent (Cook Medical, Bloomington, Ind) for stenotic lesions, 304 patients (89 men and 215 women) had contralateral symptoms (200 left and 104 right). The cause was post-thrombotic syndrome in 229 limbs and May-Thurner syndrome or nonthrombotic iliac vein lesion in 75 limbs. In this contralateral group, at 12 months, the VAS pain score improved from 5 to 0 (P < .0001), the grade of swelling went from 3 to 1 (P < .0001), and VCSS went from 5 to 3 (P < .0001) after stenting of the ipsilateral side. During the median follow-up of 20 months, 15 contralateral limbs underwent stenting. Median time to stenting of the contralateral limb after ipsilateral stenting was 9 months. The median VAS pain score, grade of swelling, and VCSS in this group before stenting were 6.5, 2, and 5 compared with 0 (P < .0001), 1 (P = .27), and 3 (P = .0021), respectively, in those members of the contralateral group who did not require stenting. Primary and primary assisted patencies at 12 months after contralateral stenting were 78% and 100%, respectively. There were no stent occlusions after contralateral stenting. ConclusionsPatients with bilateral obstructive iliofemoral venous lesions often experience improvement of the contralateral limb symptoms (95%) after stenting of the worse ipsilateral limb. Only 15 of 304 (5%) symptomatic contralateral limbs had to undergo stenting during the follow-up period because of a worsening clinical picture. Based on this, a staged approach to iliofemoral stenting in patients with bilateral symptoms focusing initially on the more symptomatic limb is suggested.

Iliac Venous Stenting for Outflow Obstruction Does Not Significantly Change the Quality of Life of Patients With Severe Chronic Venous Insufficiency

In patients with either healed (C5) or active (C6) venous ulcers, percutaneous iliac venous stenting for intravascular ultrasound-confirmed stenosis did not have a positive impact on quality of life (QoL). In a single-center study, 172 venous ulcer patients underwent iliocaval venography and intravascular ultrasound, with 109 patients having iliac vein stent placement for >50% stenosis between the years of 2006 and 2012. The remainder were treated medically. Less than half (47%) completed a QoL survey. Moderate persistent pain and postprocedure discomfort were reported in 43% of the stented and 58% of the nonstented patients. All other QoL criteria, including physical, psychological, and social activities, were similar between the cohorts. Venous ulcerations lead to significant morbidity with negative impacts on a patient's ability to engage in activities of daily living, to maintain an active lifestyle including social relationships, and to work. There have been many single-center and multicenter studies demonstrating improvements in QoL after stenting for iliac venous outflow obstruction, including several from high-volumes centers (see any study by Néglen and Raju). It behooves the treating physician to recommend interventions that are going to make an impact, heal the ulcer, and improve the patient's life. The Joint Society for Vascular Surgery and American Venous Forum Clinical Practice Guidelines (J Vasc Surg 2014;60:3S-59S) recommendation 6.14 states that “we recommend venous angioplasty and stent recanalization in addition to standard compression therapy to aid in venous ulcer healing and to prevent recurrence. [Grade - 1; Level of Evidence - C]” This study was a retrospective review with no QoL survey given as a baseline before intervention and no correlation with low QoL scores and lack of healing, stent thrombosis, or the impact of adjunctive venous procedures such as superficial venous ablation or phlebectomies. I also find this study interesting as the footnote states that the data were presented “in part” in 2014, but the manuscript was not submitted and published until 2019.

Comparison of computed tomography venography and intravascular ultrasound in screening and classification of iliac vein obstruction in patients with chronic venous disease

ObjectiveTo investigate power of computed tomography venography (CTV) to identify and characterize iliac vein obstruction (IVO) compared with intravascular ultrasound (IVUS) examination in highly symptomatic patients with chronic venous disease (CVD). MethodsCVD CEAP C3-6 limbs with visual analog scale for pain score of greater than 3 and/or Venous Clinical Severity Scale of greater than 8 were prospectively investigated with CTV and IVUS examination. The segment of maximum IVO was verified and categorically classified: group I, 0% to 49%; group II, 50% to 79%; and group III, 80% or greater. The CTV's screening power to detect the point and degree of maximum IVO was compared with IVUS. ResultsThe CTV point of maximum IVO was 80% in the left limb, 10% in the right limb, 10% bilaterally; 2% in the inferior vena cava; 91% in the common iliac vein (CIV) confluence (41.6% below the CIV confluence, 34.5 at the CIV confluence, and 23.9% above the CIV confluence); 7% at the external iliac vein (kappa index 0.841; P < .001, when compared with IVUS). The distal venous segment considered free of obstruction was above inguinal ligament: 68% (CIV, 47%; external iliac vein, 21%) 32% below the inguinal ligament (common femoral vein, 26%; deep femoral vein, 6%) (kappa index 0.671; P = .023, when compared with IVUS). The power of CTV to detect an IVO of 50% or greater (groups II and III) when compared with IVUS achieved a sensitivity and specificity ratio of 94.0% and 79.2%, respectively. The positive predictive value was 94%, the negative predictive value was 79.1%, accuracy was 86.7% (kappa, 0.733), and interobserver agreement was 92.1% (95% confidence interval, 87.1-97.7; kappa, 0.899). ConclusionsCTV is a powerful screening method in determining the precise point of compression and classifying IVO in limbs with symptomatic CVD when compared with IVUS. The prevalence of an obstruction above the iliac vein confluence is significant and should be considered in iliac vein stenting treatment strategy. The tomographic classification system proposed here may help to define the optimum technique of treatment, prognosis, and comparison of outcome results.

Key points analysis of stent implantation for iliac vein occlusion

The incidence of iliac vein occlusion is high in clinics. Most of them are latent disease. Non-thrombotic iliac vein occlusion is an important cause of chronic venous diseases in lower limbs. Post thrombotic syndrome and iliac vein compression syndrome are two main forms non-thrombotic iliac vein occlusion. Stent implantation is the first-line treatment method for iliac vein occlusion. Reasonable stent diameter selection and accurate positioning are two key technical points to ensure high patency rate of iliac vein stent. Intravascular ultrasound plays an important role in diagnosing iliac vein occlusion and stenting. After iliac vein stent implantation, regular ultrasonic follow-up is required, and optimal postoperative drug therapy is still controversial. The development and application of new specialized iliac vein stent is expected to further improve the clinical effect of iliac vein stent implantation. Key words: Iliac vein; Stent; Implantation

Factors Affecting Recurrent Deep Vein Thrombosis after Pharmacomechanical Thrombolysis and Left Iliac Vein Stent Placement in Patients with Iliac Vein Compression Syndrome

PurposeThis study evaluated the factors affecting contralateral and ipsilateral recurrent deep vein thrombosis (DVT) after iliac vein stent placement in patients with iliac vein compression syndrome (IVCS). Materials and MethodsData from 130 patients (95 female patients) who underwent catheter-directed thrombolysis and stent placement for IVCS with left lower leg thrombosis at a single institution were retrospectively analyzed. Mean patient age was 69.0 ± 14.0 years old. Median follow-up was 14 months (range, 3–164 months). Anticoagulation therapy was prescribed for 6 months, followed by lifelong antiplatelet therapy. Multivariate logistic regression analysis was performed to evaluate the factors affecting the development of contralateral and ipsilateral recurrent DVT. ResultsSeven patients (5.4%) developed contralateral DVT (median, 26 months; range, 2–61 months), and 11 patients (8.5%) developed ipsilateral DVT (median, 1 month; range, 0–53 months). Stent location (odds ratio [OR], 11.564; 95% confidence interval [CI], 1.159–115.417) and in-stent thrombosis during follow-up (OR, 15.142; 95% CI, 1.406–163.119) were predictors of recurrent contralateral DVT. Thrombophilia (OR, 47.560; 95% CI, 2.369–954.711), remaining inferior vena cava filter (OR, 30.552; 95% CI, 3.495–267.122), and in-stent thrombosis during follow-up (OR, 82.057; 95% CI, 2.915–2309.848) were predictors of ipsilateral DVT. ConclusionsContralateral DVT occurs late and is associated with extension of the iliac vein stent to the inferior vena cava and in-stent thrombosis. Ipsilateral DVT occurs relatively early and is associated with thrombophilia, remaining inferior vena cava filter, and in-stent thrombosis.

Value and Limitations of Postoperative Duplex Ultrasound for Iliac Vein Stenting

Value and Limitations of Postoperative Duplex Ultrasound for Iliac Vein Stenting

Modified one-session endovascular treatment for deep venous thrombosis with high risk of pulmonary embolism: Short-term outcomes.

To evaluate the safety and short-term outcomes of the modified one-session endovascular treatment with inferior vena cava filter placement and retrieval in one stage for the treatment of acute lower extremity deep vein thrombosis. Twenty-three patients with unilateral acute lower extremity deep vein thrombosis underwent modified one-session endovascular treatments, which were performed in one stage. Inferior vena cava filter placement without detachment, thrombectomy, and inferior vena cava filter retrieval were performed in one stage. Angioplasty and stent implantation were performed for patients with iliac vein stenosis. Venography was performed to identify the clearance of the thrombus. Color Doppler ultrasound and/or venography were conducted during the follow-up. A total of 20/23 (87%) patients with thrombus removal rate >90% successfully underwent modified one-session endovascular treatment. inferior vena cava filters were detached in 3/23 (13%) patients achieving 50%-90% thrombus removal rate. Twenty-one iliac vein stents were implanted in 21/23 (91%) patients with iliac vein stenosis. After treatment, the differences in the circumferences of the affected limb and the healthy limb both significantly decreased. No procedure-related death, symptomatic pulmonary embolism, or major bleeding occurred. During the 12-25months of follow-up, iliac vein stents and lower extremity veins maintained patent. The modified one-session endovascular treatment with one-stage inferior vena cava filter placement and retrieval might be safe for the treatment of acute lower extremity deep vein thrombosis, and the early clinical outcomes are satisfactory. Placing and retrieving an inferior vena cava filter in one session could safeguard the endovascular interventions as well as reduce the filter-related complications associated with long dwelling times.

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

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. 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. Follow-up was maintained in 90% of patients, with a mean follow-up time of 695days. 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 30days (P=0.041), 90days (P=0.045), 6months (P=0.041), and 1year (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 >1year mark (80% significantly improved or better vs. 59%, P<0.001). 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.

Study on mechanical properties of nitinol iliac vein stent and animal test under different release scales

The mechanical properties of nitinol iliac vein stent (NIVS) have been studied by many scholars at home and abroad, but the study on the mechanical properties of iliac vein stent under different release scales has not been reported yet. Based on the finite element analysis method, the mechanical properties of three self-developed NIVS were studied to reveal the influence of stent diameters (12, 14, 16 mm) and different release scales (80%, 90%) on its strength, fatigue life and vein wall biomechanical properties. With an increases in the release scales, the equivalent elastic strain, fatigue strength safety factors, and vessel wall equivalent stress exhibited a downward trend, while the most stressed cross-section coincided with the arc of stent-connecting rods. Through 30, 60 and 90 days' animal test, a narrowed vascular model was established in the iliac veins of 12 pigs, and the developed iliac vein stents were implanted to comprehensively evaluate the safety and effectiveness of the stent, and at the same time the mechanical properties of stents were verified to provide important reference for the type inspection and clinical trials of follow-up products.

Etiology of iliocaval stent thrombosis

ObjectiveAlthough correction of iliac vein stenosis is safe and efficacious, one of its major complications is iliac vein stent thrombosis. In an attempt to examine the cause of iliac vein stent thrombosis, we reviewed the location of underlying lesions encountered after thrombectomy or thrombolysis of iliac vein stents. MethodsA retrospective analysis was performed of all iliac vein venograms with intravascular ultrasound examinations at our office-based surgical center from February 2012 to July 2016. Patients included in the study had chronic venous insufficiency and failed compression therapy. All procedures were performed with local anesthesia and conscious sedation. Wallstents were used in all procedures for nonthrombotic iliac vein stenosis, ranging from 8 to 24 mm in diameter and 40 to 90 mm in length. Patients were followed with transcutaneous duplex every 3 months for the first year and every 6 to 12 months thereafter. Patients were placed on clopidogrel for 3 months or continued on their preexisting anticoagulants. ResultsFrom February 2012 to July 2016, we performed 2228 iliac vein venograms with intravascular ultrasound examination in 1381 patients. The mean age of the patient population was 65 ±14 years (range, 21-99 years), among which 876 were female. A total of 1037 procedures were performed in the left lower extremity. Of these, 240 venograms were diagnostic. Presenting symptoms based on CEAP classification included C2 (n = 21), C3 (n = 633), C4 (n = 1065), C5 (n = 269), and C6 (n = 241). Complete thrombosis of the iliac vein stent was noted in 18 patients (0.8%) who thereafter underwent suction thrombectomy with thrombolysis. None of these patients had a prior history of deep vein thrombosis. In-stent restenosis was noted in 11 patients. Proximal lesions were found in no patients. An external iliac vein lesion was found distal to the common iliac vein stent in two patients. Common femoral vein lesions were found in six patients. These encountered lesions were then stented. All patients who underwent thrombectomy were placed on anticoagulation for 6 months. No patient were noted to suffer rethrombosis upon follow-up. No correlation with stent thrombosis was encountered for age, gender, laterality, location, presenting symptoms, or length or diameter of the stent. ConclusionsBased on our experience, in-stent restenosis followed by inflow lesions in the common femoral vein are the most common causes of stent thrombosis. These data suggest a need for future research to target these areas.

Venous Ulcers as a Rare Presentation of Bilateral May-Thurner Syndrome in Male Patients. Case Series

Introduction: Objectives May-Thurner syndrome (or iliac vein compression syndrome, IVCS), is referred to iliac vein compression by the iliac artery against the spine. It is commonly found as an underlying cause of iliofemoral deep venous thrombosis (DVT). The syndrome is mostly seen in women (in the second through the fourth decades of age) and on the left side. In this article, we describe a rare presentation of IVCS in male patients with bilateral May-Thurner syndrome. Methods - Five male patients (mean age was 45.5, SD 14.0 year), presented with bilateral leg edema and recurrent active venous ulcers for more than one years that failed consistent compression therapy. All patient have no current or previous history of DVT. IVCS was diagnosed using Duplex ultrasound and direct multi-slice computed tomography-venogram (CTV). Endovascular treatment was performed in the form of bilateral common iliac vein stenting (WALLSTENT, Boston Scientific), Radiofrequency ablation of great saphenous vein (GSV) was done for one patients with GSV reflux. Vascular Clinical Severity Score (VCSS), Visual Analog Score (VAS), and Venous Disability Score (VDS) were assessed preoperatively, at one month and 6 months after the intervention. Results - The intervention was technically successful with no perioperative complications in all patients. At 1-month follow-up, the venous ulcers were completely healed on both sides in all patients (9 limb), one limb in one patient need additional ablation of the refluxing GSV. VCSS, VDS, VAS have improved to 6/27, 2/4, 3/10 compared to preoperative values of 14/27, 3/4, and 7/10, respectively. All patients were free of pain with no residual edema in both legs. At 6 months follow-up: VCSS, VDS and VAS have improved to 4/27, 0/4, and 1/10, respectively, compared to the preoperative values baseline values. Conclusion - May-Thurner syndrome is a relatively common anatomical variant where iliac vein compression is typically presented with venous insufficiency symptoms on the left lower extremity in middle aged women. This report is to describe a rare presentation of symptomatic bilateral May-Thurner syndrome in a male patient. All patients were successfully treated with stenting of both common iliac veins, which improved the patients' symptoms including complete healing of the venous ulcers in both legs. In conclusion, the conventional endovascular treatment of May-Thurner syndrome can also be an effective treatment option of male patients with atypical presentation of IVCS.

Thrombotic Outcomes Following Hormonal Treatment of Heavy Menstrual Bleeding in Pediatric Patients Taking Anticoagulation

Introduction: Anticoagulant-associated heavy menstrual bleeding (HMB) is a common and under recognized complication in women who are being treated for venous thromboembolism (VTE), leading to complications such as anemia and decreased quality of life. The appropriate management of HMB in this population is complex and often requires hormonal therapy which may significantly increase the risk for VTE. Additionally, combined oral contraceptives may need to be used to control heavy menstrual bleeding despite contributing to the overall risk for VTE. Due to limited adult and pediatric data, there are currently no expert consensus guidelines for the treatment of anticoagulant-associated HMB. We describe a single institutional experience and thrombotic outcomes following hormonal therapy for anticoagulation-associated HMB in adolescents. Methods: A retrospective cohort of pediatric females ages 9-21 years treated at Children's Healthcare of Atlanta were identified between January 2016 and July 2019. Patients were identified using common ICD codes for both HMB and anticoagulation/thrombosis. Patient demographic information, clinical characteristics, and thrombotic outcomes were abstracted from review of the electronic medical record. Patients receiving anti-platelet therapy with clopidogrel were included due to the reported similarity of bleeding complications compared to anticoagulants. Summary statistics were performed and Student's t test, Fisher's exact test, and Chi square test were used for statistical analysis (SAS v9.4, 2012, Cary, NC, USA). A p value &lt;0.05 was considered statistically significant. Results: The cohort was comprised of 17 adolescent females with confirmed anticoagulation-associated HMB. Among the cohort, 59% identified as White, 35% Black, and 6% Asian. Body Mass Index was normal in 41%, while 24% were obese and 35% were underweight. Indications for anticoagulation included VTE (n=11), pulmonary embolism (n=6), May-Thurner Syndrome with placement of iliac vein stent (n=3), and other vascular anomalies with confirmed stenosis/thrombosis (n=2). The most common risk factor for thrombosis was initiation of combined hormone oral contraceptives within 3 months of the event that led to initiation of anticoagulation (35%). Anticoagulant medications used included lovenox (n=13), clopidogrel (n=3), and lovenox/aspirin (n=1). The median age at initiation of hormonal therapy for HMB was 17.3 years (min-max, 12.6-18.3 years), with a median time between starting anticoagulation and initiation of hormonal therapy of 11 days (min-max, 0-529 days). Medications used to treat HMB included medroxyprogesterone (n=9), norethindrone (n=6), norethindrone-ethinyl estradiol (n=1), and etonogestrel implant (n=1). After initiating hormonal therapy, amenorrhea or menstrual suppression was reported in all but one individual (n=16/17). Following initiation of hormonal therapy with medroxyprogesterone, only one adolescent experienced a new VTE event. This adolescent had the additional risk factors of May-Thurner anatomy, heterozygous FV Leiden and prothrombin gene mutations, and antiphospholipid antibody syndrome. The median length of follow-up from initiation of hormonal therapy was 325 days (min-max, 43-932 days). Statistical differences between groups were not feasible due to small sample size and few outcome events. Conclusions: The proper treatment of anticoagulation-associated HMB using hormonal therapy in the pediatric population is unclear, but our data suggest that treatment with hormonal therapy reduces anticoagulation-associated HMB while adding minimal risk for VTE. The only VTE event that occurred in our cohort was in the setting of multiple strong risk factors for VTE. Larger pediatric studies are required in order to confirm these findings. Disclosures White: National Hemophilia Foundation: Other: Shire Clinical Fellowship Program. Sidonio:Novo Nordisk: Membership on an entity's Board of Directors or advisory committees; Kedrion: Research Funding; Uniqure: Membership on an entity's Board of Directors or advisory committees; Biomarin: Membership on an entity's Board of Directors or advisory committees; Grifols: Membership on an entity's Board of Directors or advisory committees, Research Funding; Octapharma: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bioverativ: Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda-Shire: Membership on an entity's Board of Directors or advisory committees, Research Funding; Genetech: Membership on an entity's Board of Directors or advisory committees, Research Funding.

Vascular conflicts in andrology. Part 2. Lower level arteryovenous conflicts

This paper presents a review of the literature on the prevalence, classification, symptoms, diagnosis and treatment of lower level arteriovenous conflicts. New approaches in the treatment of both arteriovenous conflicts and comorbid diseases such as varicocele, varicose veins of the pelvic organs, venogenic erectile dysfunction, chronic pelvic pain syndrome are presented. The data of the literature review can form the basis for the revision of approaches to the management of patients with varicocele, erectile dysfunction and chronic recurrent prostatitis. It is shown that x-ray surgical embolization of prostatic plexus veins alone or in combination with testicular vein embolization, angioplasty and iliac vein stenting is possible only at the junction of urology, andrology and x-ray surgery.

Iliac Vein Stent Placement and the Iliocaval Confluence

Prior literature has recommended routine iliac vein stent extension into the inferior vena cava (IVC) to assure adequate outflow for iliac vein stenting procedures. Our bias was that only the lesion should be stented without routine stent extension up to the IVC. We report our experience with this limited stenting technique. From 2012 to 2015, 844 patients (1,216 limbs) underwent iliac vein stenting for nonthrombotic iliac vein lesions (NIVLs). All limbs were evaluated in accordance with the presenting sign of the Clinical-Etiology-Anatomy-Pathophysiology (CEAP) score, and duplex scans and intravascular ultrasound (IVUS) showing more than 50% cross-sectional area or diameter reduction. All study patients had failed 3months of conservative management. The procedures of iliac vein stenting were all office based. Two techniques were compared: (1) placement of the iliac vein stent to cover the lesion and terminating cephalad into the IVC if the lesion involved the common iliac vein and (2) placement of the iliac vein stent to cover the lesion only and not passing the iliocaval confluence if the lesion only involved the external iliac vein. Complications were assessed during 30-day follow-up using the duplex scan technique to look for thrombosis. Of the total 844 patients, 543 (64%) were women. The average age was 66 (±14.2) years (range, 21-99years). The stent was placed in the left lower limb in 474 patients and bilaterally in 370 patients. The presenting sign in accordance with the CEAP classification was C3=626, C4=404, C5=44, and C6=141. The average iliac vein stenosis by IVUS was 62% (±12% standard deviation [SD]). We had 715 patients with the iliac vein stent extending into the IVC, and of these, 8 patients had thrombosis within 30days after the procedure. On the other hand, 501 patients had the iliac vein stent without crossing the iliocaval confluence, and of these, 4 patients had thrombosis within 30days of the procedure. There was no difference between these 2 groups in regard to gender (P=0.1) or age (P=0.3). Laterality was statistically different (P<0.0001) with more stents to be extended into the IVC if the lesion is in the left lower limb. Comparing these 2 groups in regard to 30-day thrombosis as a complication was not statistically significant (P=0.6). There was no statistical difference between the 2 groups in regard to the presenting sign CEAP (P=0.6). These results question the need for routine iliac vein stent extension into the IVC in patients with NIVLs. We were not able to demonstrate a significant risk of thrombosis with just placing the stent to cover the lesion only with short-term follow-up.