One-year outcomes of a novel venous stent for symptomatic iliofemoral venous obstruction: prospective cohort study.

BACKGROUND: A stent with characteristics of a hybrid design may have advantages in improving the patency of symptomatic iliofemoral vein obstruction. This study assessed the safety and effectiveness of the V-Mixtent Venous Stent in treating symptomatic iliofemoral outflow obstruction. METHODS: Eligible patients had a Clinical-Etiologic-Anatomic-Physiologic (CEAP) C classification of ≥ 3 or a Venous Clinical Severity Score (VCSS) pain score of ≥ 2. The primary safety endpoint was the rate of major adverse events within 30 days. The primary effectiveness endpoint was the 12-month primary patency rate. Secondary endpoints included changes in VCSS from baseline to 6 and 12 months, alterations in CEAP C classification, Chronic Venous Disease Quality of Life Questionnaire (CIVIQ-14) scores at 12 months, and stent durability measures. RESULTS: Between December 2020 and November 2021, 171 patients were enrolled across 15 institutions. A total of 185 endovenous stents were placed, with 91.81% of subjects receiving one stent and 8.19% receiving 2 stents. Within 30 days, only two major adverse events occurred (1.17%; 95% confidence interval [CI], 0.14-4.16%), below the literature-defined performance goal of 11% (P < .001). The 12-month primary patency rate (91.36%; 95% CI, 85.93-95.19%; P < .001) exceeded the literature-defined performance goal. VCSS changes from baseline demonstrated clinical improvement at 6 months (- 4.30 ± 3.66) and 12 months (- 4.98 ± 3.67) (P < .001). Significant reduction in symptoms, as measured by CEAP C classification and CIVIQ-14, was observed from pre-procedure to 12 months (P < .001). CONCLUSIONS: The 12-month outcomes confirm the safety and effectiveness of the V-Mixtent Venous Stent in managing symptomatic iliofemoral venous outflow obstruction, including clinical symptom improvement compared to before treatment.

Which one is the best in treating deep venous thrombosis -- percutaneous mechanical thrombectomy, catheter-directed thrombolysis or combination of them?

OBJECTIVE: To compare the treatment outcomes among percutaneous mechanical thrombectomy (PMT) with AngioJet, Catheter-directed thrombolysis (CDT), and a combination of both. METHODS: One hundred forty nine patients with acute or sub-acute iliac-femoral vein thrombosis accepting CDT and/or PMT were divided into three groups respectively: PMT group, CDT group, PMT + CDT group (PMT followed by CDT). The severity of thrombosis was evaluated by venographic scoring system. Technical success was defined as restored patent deep venous blood flow after CDT and/or PMT. Clinical follow-up were assessed by ultrasound or venography imaging. The primary endpoints were recurrence of DVT, and severity level of post-thrombotic syndrome (PTS) during the follow-up. RESULTS: Technical success and immediate clinical improvements were achieved on all patients. The proportion of sub-acute DVT and the venographic scoring in PMT + CDT group were significantly higher than that in CDT group and PMT group (proportion of sub-acute DVT: p = 0.032 and p = 0.005, respectively; venographic scoring: p < 0.001, respectively). The proportion of May-Thurner Syndrome was lower in PMT group than that in CDT and PMT + CDT group (p = 0.026 and p = 0.005, respectively). The proportion of DVT recurrence/stent thrombosis was significantly higher in CDT group than that in PMT + CDT group (p = 0.04). The severity of PTS was the highest in CDT group ( χ2 = 14.459, p = 0.006) compared to PMT group (p = 0.029) and PMT + CDT group (p = 0.006). CONCLUSION: Patients with sub-acute DVT, high SVS scoring and combined May-Thurner Syndrome were recommended to take PMT + CDT treatment and might have lower rate of DVT recurrence/stent thrombosis and severe PTS. Our study provided evidence detailing of PMT + CDT therapy.

Selective iliofemoral stent placement for complex pediatric cases: a decade of institutional experience.

BACKGROUND: Pediatric iliofemoral venous thromboembolism that is resistant to conventional treatments poses significant management challenges. Stent placement represents a potentially underutilized strategy in children when stenosis or thrombosis persists intraprocedurally or recurs postoperatively, despite treatments such as venoplasty, lysis, and thrombectomy. OBJECTIVE: This study aims to report our institutional experience with iliofemoral stenting in 17 pediatric patients with recurrent iliofemoral venous thromboembolism or stenosis. MATERIALS AND METHODS: We performed an IRB-approved retrospective review of pediatric patients (<18 years of age) who underwent iliofemoral venous stenting for recurrent stenosis or thrombosis between January 2012 and December 2022 at a single tertiary care institution. Patient demographics, risk factors for venous thromboembolism, presenting symptoms, and procedural characteristics were recorded. The primary outcome was stent patency rates at interval imaging follow-up. RESULTS: Seventeen patients with mean age of 14.6 years (range 7-17) and mean BMI of 27.7 were stented during the study period. Sixteen of 17 patients presented with evidence of May-Thurner anatomy. 14/17 patients presented with acute iliofemoral venous thromboembolism, 2/17 with chronic venous thromboembolism, and 1/17 with left lower extremity swelling without thrombosis. Seventy-three total angiographic procedures were performed, which included angioplasty, lysis, and thrombectomy, and 23 stent placements. Patients underwent an average of 3 procedures (range 1-9) over a mean of 2.8 months (range 0-17 months) prior to undergoing stent placement. Stents were deployed successfully in all patients. The median follow-up was 18 months (range, 1-77 months). Primary and secondary patency rates were 13/17 (76%) and 14/14 (100%) at 12 months and 12/17 (71%) and 14/14 (100%) at 24 months, respectively. CONCLUSION: In our experience of 17 patients, stent placement appears to be a durable option for children with iliofemoral venous thromboembolism following failure to establish vessel patency or development of recurrent thrombosis/stenosis postoperatively.

Total Iliocaval Reconstruction in a Complex Palliative Patient with Malignant Inferior Vena Cava Syndrome.

Inferior vena cava (IVC) compression secondary to mass effect is accompanied by edema, ascites, back and abdominal pain, and central nervous system symptoms. Most IVC syndrome cases described in the literature focus on the focal treatment of IVC lesions, and reports of complete iliocaval reconstructions secondary to malignant IVC syndrome in the palliative context are limited. In this case report, we describe the clinical presentation, technical approach, and symptomatic outcomes of a patient with extensive malignant compression and invasion of the iliofemoral venous system. An 82-year-old male with metastatic lung cancer invading the right upper quadrant of the abdomen presented with scrotal and bilateral lower extremity edema, as well as anasarca. Computed tomography (CT) demonstrated an 11 cm right adrenal metastasis and extensive retroperitoneal lymphadenopathy resulting in the compression of the IVC and iliac veins. Femoral venography demonstrated extensive collateral venous pathway formation with the opacification of the para-lumbar and vertebral veins, in addition to the vertebral/sacral venous plexus. Iliocaval reconstruction was performed using venous-dedicated stents. This case report highlights a technically successful total iliocaval reconstruction in a complex palliative patient with diffuse metastatic disease resulting in IVC compression and syndrome.

The Safety and Efficacy of ZelanteDVT™ Catheter Rheolytic Thrombectomy in the Treatment of Patients with Iliac Vein Stent Thrombosis.

BACKGROUND: To examine the safety and efficacy of ZelanteDVT™ catheter rheolytic thrombectomy in the treatment of patients with iliac vein stent thrombosis. METHODS: A retrospective analysis method was conducted by means of collecting the data of 32 patients who had completed the treatment of iliac vein stent thrombosis with ZelanteDVT catheter rheolytic thrombectomy from March 2019 to March 2023. Data on clinical characteristics, technical success, clinical success, complications, and early follow-up were analyzed. RESULTS: The technical success rates were 100%, intraoperatively, in which 22 cases were improved to thrombus clearance Grade II (50-90%), 10 were Grade III (>90%). There were 21 cases treated with subsequent catheter-directed thrombolysis, and the average urokinase administration of (120.90 ± 29.63)∗10ˆ4 units. The clinical success rates were 100% and the swelling of the affected limbs were significantly improved, a significant difference in the pre/postoperative between-thigh circumference difference [(5.16 ± 1.08) vs. (1.75 ± 0.84), P < 0.000]. The pre/postoperative Venous Clinical Severity Score was [(12.94 ± 1.70) vs. (7.44 ± 1.31), P < 0.000]. No serious complications occurred during the perioperative period. The postoperative and 12-month stent patency rate was 100.00% (32/32) and 71.88% (23/32), respectively. CONCLUSIONS: The ZelanteDVT catheter rheolytic thrombectomy seems to have a promising application prospect for the treatment of patients with iliac vein stent thrombosis.

Successful Surgical Extraction of an Embolized Iliac Vein Stent from the Right Heart: A Case Report.

BACKGROUND Stenting of the iliac vein remains one of the therapeutic options for the treatment of May-Thurner syndrome. Embolization of peripheral venous stents due to improper technique is a feared complication with an estimated incidence of 1% to 3%. Here we describe an interesting case of an embolized iliac vein stent in the right heart that was successfully extracted via a surgical approach. CASE REPORT A 52-year-old woman with a past medical history of hypertension, diabetes mellitus, and iliac vein stent (16×60 mm Zilver Vena) placement for May-Thurner syndrome presented for evaluation of shortness of breath, chest pain, and dizziness. A chest X-ray was performed, revealing a large stent in the cardiac silhouette. An echocardiogram showed a dense material across the tricuspid valve extending from the right atrium into the right ventricle. A percutaneous endovascular attempt to retrieve the stent was unsuccessful and led only to partial stent retrieval. An open sternotomy approach by a cardiac surgeon revealed the embolized stent across the tricuspid valve covered by endothelial tissue. The stent was successfully extracted without any need for tricuspid valve repair or replacement, followed by an uneventful postoperative recovery. CONCLUSIONS The percutaneous approach is the preferred initial option for the extraction of embolized iliac vein stents into the heart. However, when such an approach fails, the surgical approach remains a feasible option. As reported in this case, the surgical retrieval of a stent can be done without any need for either tricuspid valve repair or replacement.

The use of superficial circumflex iliac perforator (SCIP) pedicle vein for lymphovenous anastomosis to treat inguinal lymphatic fistula: A case report.

The management of lymphatic fistulas following surgical procedures, in particular after inguinal lymphadenectomy, represents a significant clinical challenge. The current case report shows the novel use of the superficial circumflex iliac perforator (SCIP) pedicle vein for lymphovenous anastomosis (LVA) to treat a chronic inguinal lymphatic fistula in a 58-year-old male patient. This patient had developed a persistent lymphorrhea and wound dehiscence after a right inguinal lymph node biopsy performed for oncological reasons 1.5 months before. Pre-operative assessment with indocyanine green (ICG) lymphography confirmed a substantial lymphatic contribution to the wound discharge, thus guiding the surgical strategy. During the procedure, a pedicled tissue segment containing the SCIV was dissected and utilized to fill the wound's dead space and facilitate LVA with the leaking lymphatic vessel. Notably, a coupler device was employed for the anastomosis due to the large caliber of the lymphatic vessel involved, a technique not commonly reported in lymphatic surgeries. The result of the procedure was successful, with intra-operative ICG imaging confirming the patency of the anastomosis. After surgery the wound healed without complications. This case illustrates the potential of SCIV employment in lymphatic fistula repair in the inguinal region. While further research is needed to validate these findings, this report provides an unconventional approach to a relatively common problem in clinical practice.

[Application of iliac vein molding and stent implantation through the ipsilateral great saphenous vein approach in daytime treatment mode].

OBJECTIVE: To explore the feasibility and recent efficacy of iliac vein molding and stenting in daytime treatment mode in patients with iliac vein stenosis. METHODS: Medical records of iliac vein molding and stenting performed in the ipsilateral great saphenous vein approach conducted from February 2017 to March 2022 were retrospective reviewed. There were 21 cases, 6 males and 15 females. Age ranged from 37 to 79 years [(62.5 ± 10.2) years]. The stenosis in the 21 limbs simply involved the common iliac veins in 16 patients, 2 patients had the simple and external iliac veins, and both the total and external iliac veins in 3 patients. Both iliac vein molding and iliac vein stenting were performed through the ipsilateral great saphenous vein approach. The patients with simple iliac vein stenosis with great saphenous vein valve insufficiency also underwent radiofrequency closure of great saphenous vein and flexural vein sclerosis therapy simultaneously. Regular postoperative direct oral anticoagulants therapy and stress therapy were followed. All the patients were hospitalized for less than 24 h. RESULTS: All the 21 patients operations were successful (the success rate was 100%), without any intraoperative complications. Immediate postoperative complications were puncture point bleeding in 1 case. The bandage gauze was completely wet. The bleeding was stopped after 5min of recompression. All the patients were hospitalized for less than 24 h. Follow-up results: The 3-month follow-up rate after operation was 100%. Absolute effective 18 cases (18/21, 85.7%). Relatively effective(postmentation still after surgery, but with less extent) in 3 cases (3/21, 14.3%). The iliac vein stents were unobstructed, and the trunk of the great saphenous vein was well closed in the patients with great saphenous vein radiofrequency treatment. The 6-month follow-up rate after operation was 71.4%(15/21). Of these, 14 cases (14/15, 93.3%) were absolutely effective. Relatively effective(postmentation still after surgery, but with less extent) in 1 case (1/15, 6.7%). The iliac vein stents were no restenosis or obstruction, and the trunk of the great saphenous vein was well closed in the patients with great saphenous vein radiofrequency treatment. CONCLUSION: The interventional treatment technique of iliac vein stenosis is feasible in the daytime treatment mode, with clear advantages and satisfactory recent efficacy.

In vivo evaluation of safety and performance of a tapered nitinol venous stent with inclined proximal end in an ovine iliac venous model.

A tapered stent with inclined proximal end is designed for fitting the iliac anatomically. The aim of the present study was to evaluate the safety and performance of the new stent in ovine left iliac veins. The experiment was performed in 30 adult sheep, and one nitinol-based VENA-BT® iliac venous stent (KYD stent) was implanted into each animal's left common iliac vein. Follow-up in all sheep consisted of angiographic, macroscopic, and microscopic examinations at Day 0 (< 24 h), Day 30, Day 90, Day 180 and Day 360 post-stenting (six animals per each time-point). 30 healthy ~ 50 kg sheep were included in this study and randomly divided into five groups according to the follow-up timepoint. All stents were implanted successfully into the left ovine common iliac vein. No significant migration occurred at follow-up. There is no statistically significant difference between the groups (p > 0.05), indicating no serious lumen loss occurred during the follow-up period. Common iliac venous pressure was further measured and the results further indicated the lumen patency at follow-up. Histological examinations indicated that no vessel injury and wall rupture, stent damage, and luminal thrombus occurred. There was moderate inflammatory cell infiltration around the stent in Day-0 and Day-30 groups with the average inflammation score of 2.278 and 2.167, respectively. The inflammatory reaction was significantly reduced in Day-90, Day-180 and Day-360 groups and the average inflammation scores were 0.9444 (p < 0.001, Day-90 vs Day-0), 1.167 (p < 0.001, Day-180 vs Day-0) and 0.667 (p < 0.001, Day-90 vs Day-0), respectively. The microscopic examinations found that the stents were well covered by endothelial cells in all follow-up time points. The results suggested that the KYD stent is feasible and safe in animal model. Future clinical studies may be required to further evaluate its safety and efficacy.

Iliac Vein Stenting and Thrombectomy Result in Limb Salvage in Phlegmasia Caerulea Dolens as a Result of Heavy Fibroid Burden.

Phlegmasia cerulea dolens is a devastating sequelae of propagating deep vein thrombosis causing total venous outflow obstruction of an extremity. It is characterized by significant pain, edema, cyanosis, and critical limb ischemia and may progress toward venous gangrene. Morbidity and mortality rates associated with this phenomenon are high. Treatment options are limited and consist of early and aggressive therapeutic anticoagulation and fluid resuscitation, followed by thrombectomy or thrombolysis if the patient fails to respond clinically in 6-12 hours.

Risk Factors for Venous Thromboembolism and Eventual Amputation in Traumatic Femoral and Iliac Vein Injuries: A Trauma Quality Improvement Program Analysis.

BACKGROUND: Iliac and femoral venous injuries represent a challenging dilemma in trauma surgery with mixed results. Venous restoration of outflow (via repair or bypass) has been previously identified as having higher rates of VTE (venous thromboembolism) compared to ligation. We hypothesized that rates of VTE and eventual amputation were similar whether restoration of venous outflow vs ligation was performed at initial operation. METHODS: Patients in the 2019-2021 National Trauma Data Bank with iliac and femoral vein injuries were abstracted and analyzed. The primary outcomes of interest were in-hospital lower extremity amputation and VTE. RESULTS: A total of 2642 patients with operatively managed iliac and femoral vein injuries were identified VTE was found in 10.8% of patients. Multivariable logistic regression was performed and identified bowel injury, higher ISS, older age, open repair, and longer time to VTE prophylaxis initiation as independent predictors of VTE. Amputation was required in 4.2% of patients. Multivariable logistic regression identified arterial or nerve injury, femur or tibia fracture, venous ligation, percutaneous intervention, fasciotomy, bowel injury, and higher ISS as independent factors of amputation. CONCLUSION: Venous restoration was not an independent predictor of VTE. Venous ligation on index operation was the only modifiable independent predictor of amputation identified on regression analysis.

Single-session mechanical thrombectomy for iliofemoral deep vein thrombosis using a dual mechanism of action device combining basket and rotational thrombectomy.

OBJECTIVE: Interventional treatments for acute iliofemoral deep vein thrombosis (DVT) remain controversial after publication of the Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis (ATTRACT) study. Interventions have been shown to reduce post-thrombotic syndrome severity and improve quality of life in DVT patients, but have been accompanied by risk of major bleeding from thrombolytics. We describe thrombus removal using a novel combined basket-rotational thrombectomy device that minimizes the need for thrombolytics or repeat procedures. METHODS: The aim of this prospective, nonrandomized, multicenter, first-in-human study of 19 patients with acute iliofemoral DVT was to evaluate the safety and performance of the Pounce venous thrombectomy system ≤12 months after treatment. The primary performance end point was defined as procedural success through achievement of Society of Interventional Radiology (SIR) grade II lysis in treated vessels with freedom from procedural adverse events. Secondary end points included venous disease severity assessments using the Villalta scale and the Venous Clinical Severity Score, patient quality-of-life measurement using the Venous Insufficiency Epidemiological and Economic Study-Quality of Life questionnaire, and calf circumference measurements taken at baseline, 24 hours, and 1 month. RESULTS: The primary end point of complete or near-complete thrombus removal (Society of Interventional Radiology grade II or III) was achieved in all patients. All study device-related safety end points were met, with no major bleeding or device-related adverse events. Of the 19 patients treated, 16 (84.2%) did not receive thrombolytics during the procedure. Post-thrombotic syndrome (Villalta scale >4) was identified in 17 of 19 patients (89.5%) at baseline, 4 of 13 patients (30.8%) available for follow-up at 6 months, and 2 of 11 patients (18.2%) at 12 months. The median Venous Clinical Severity Score decreased (P < .001) from 8.5 (interquartile range [IQR], 7-10) at baseline to 4 (IQR, 2-4) at 1 month after the procedure and was similar at 6 months (2; IQR, 2-5) and 12 months (2; IQR, 1.5-3) after the procedure. The median Venous Insufficiency Epidemiological and Economic Study-Quality of Life questionnaire score improved (P < .001) by 39 from baseline (57; IQR, 53.5-74) to 1 month (96; IQR, 86-101) after the procedure, and remained high at 6 months (99; IQR, 75-103) and 12 months (98; IQR, 94.5-100). The median calf circumference decreased (P = .089) from 39 cm (IQR, 35-47.8 cm) at baseline to 36 cm (IQR, 32.5-40.5 cm) at 24 hours after the procedure and was 34.5 cm (IQR, 33.2-38.5 cm) at 1 month. CONCLUSIONS: The Pounce device is safe and effective for removal the of thrombus in patients with acute iliofemoral DVT. Initial results demonstrate improvements in venous disease severity and patient quality of life.

Empty vein ablation (EVA) technique: an in-vivo animal model to assess the effects of sclerosing agent concentration and wall contact time on intima and media tunicae structure.

BACKGROUND: Sclerotherapy is a cornerstone of the treatment of chronic venous disease, despite some technical aspects (e.g., sclerosant liquid agent concentration [SLAC] and contact time between sclerosant agent and vein wall [ctSA/VW]) to maximize outcomes remain an unsolved problem and a source of debate. An innovative three-balloon catheter has been developed to allow sclerotherapy in empty vein conditions (Empty Vein Ablation technique, EVA), revolutionizing the definition of SLAC and ctSA/VW. Aim of this experimental study is to analyze EVA effects on intima and media vessel tunicae using different SLAC and ctSA/VW in an in-vivo animal model. METHODS: Two adult sheep were treated by EVA using jugular and common iliac vein axes (eight vein segments). Different SLAC (polidocanol 0.5% or 1%) and different ctSA/VW (3 or 5 minutes) were combined for testing residual circumferential intima percentage and media thickness after EVA. RESULTS: Intact circumferential residual intima after the treatment was 21.3±4.9%, 18.2±7.4%, 15.7±2.4% and 8.9±2.0% using 0.5% (3 min), 0.5% (5 min), 1% (3 min) and 1% (5 min), respectively (R2=0.945; control sample: 97.6%). Media thickness after the treatment was 121.6±35.3 µm, 110.9±7.8 µm, 96.1±30.4 µm and 79.1±34.1 µm using 0.5% (3 min), 0.5% (5 min), 1% (3 min) and 1% (5 min), respectively (R2=0.990; control sample 125.7 µm). No significant modifications were detected analyzing the adventitia in all samples. CONCLUSIONS: EVA proved to be effective in venous wall destruction even with a very low SLAC and ctSA/VW (0.5% in 3 minutes), in quite large caliber veins. Direct comparisons with foam/liquid sclerotherapy should be done to confirm therapeutic effectiveness of these results, despite EVA has provided a maximized and controlled SA/VW contact time and ratio.

Thrombectomy of the Profunda Femoral Vein in Iliofemoral Deep Venous Thrombosis Using an Antegrade Popliteal Approach.

PURPOSE: Residual or undertreated inflow disease is a major cause of stent occlusion following endovascular thrombectomy for iliofemoral deep venous thrombosis (DVT). The profunda femoral vein (PFV) is an important inflow vessel alongside the femoral vein but is traditionally challenging to treat via an antegrade popliteal approach. This technical note describes a novel approach for PFV clearance in iliofemoral thrombectomy via the popliteal vein. MATERIALS AND METHODS: Eight patients underwent PFV clearance as part of iliofemoral DVT thrombectomy via an antegrade popliteal approach. In seven patients, a popliteal-profunda communicating vessel was identified permitting PFV access and thrombectomy. In one patient, a popliteal-profunda communicator was not identified and an 'up and over' approach via the femoral bifurcation from the same popliteal access was utilised. Thrombectomy was performed using the Inari ClotTriever device or Penumbra's Indigo system. RESULTS: Technical success in PFV thrombectomy was 100%. Six patients (75%) underwent stenting for an iliac stenotic lesion or May Thurner compression point. At the four-week ultrasound follow-up, the pelvic iliofemoral segment was patent in 7 patients (87.5%). The PFV was patent in 7 patients (87.5%) whereas the FV was only patent in 4 patients (50%). One patient underwent reintervention for iliofemoral stent occlusion. No PFV injury occurred and no post-procedure profunda reflux was identified. CONCLUSION: PFV clearance can be achieved via an antegrade popliteal approach in iliofemoral thrombectomy to optimise inflow, negating the need for alternative or additional venous access. PFV may maintain upstream iliofemoral vein patency even with an occluded femoral vein. LEVEL OF EVIDENCE: Level 4, Case Series.

A rare etiology of frequent ventricular ectopy: Embolic complication of a venous iliac stent to the right ventricle.

Peripheral venous stent migration is an exceedingly rare complication of endovascular stenting. In this clinical vignette, we present a case of a 74-year-old male with a history of endo-venous laser ablation therapy of the right greater saphenous vein complicated with an occlusion requiring a left iliac vein stent. The patient presented to the clinic months after the procedure with complaints of palpitations. Multimodality imaging revealed a stent that had become dislodged and was now located in the right ventricle, trapped within the tricuspid valve apparatus.

Femoral vein stenting versus endovenectomy as adjuncts to iliofemoral venous stenting in extensive chronic iliofemoral venous obstruction.

PURPOSE: To compare femoral endovenectomy with the creation of an arteriovenous fistula (FE + AVF), versus iliofemoral endovenous stenting with the concurrent extended femoral vein (FV-S) stenting in patients with chronic iliofemoral venous obstruction (IFVO). MATERIALS AND METHODS: In a randomized prospective single-center study, 48 received (FV-S), while the other 54 had (FE + AVF). RESULTS: There were no statistically significant differences in the primary outcomes between the two groups (FV-S) and (FE + AVF) (59% vs 56.8%, 75% vs 79.1%, respectively). At a median of 13 months after the treatment. However, the FV-S group's patients experienced fewer postoperative problems (p = .012), shorter procedures (p = .001), and shorter stays in the hospital (p = .025). CONCLUSION: There is no difference between the efficacy and symptomatic resolution of the FV-S group and the FE + AVF group at the same time, FV-S has lower postoperative complications and a shorter procedure duration and hospital stay.

Histological Features of In-Stent Restenosis after Iliac Vein Thrombus Removal and Stent Placement in a Goat Model.

PURPOSE: To establish an animal model for in-stent restenosis (ISR) after postthrombotic iliac vein stent placement and characterize histopathological changes in tissue within the stented vein. MATERIALS AND METHODS: Iliac vein thrombosis was induced using balloon occlusion and thrombin injection in 8 male Boer goats. Mechanical thrombectomy and iliac vein stent placement were performed 3 days after thrombosis induction. Restenosis was evaluated by venography and optical coherence tomography (OCT) at 1 and 8 weeks after stent placement, and stent specimens were taken for pathological examination after the animals were euthanized. RESULTS: Thrombosis induction was successful in all 8 goats, with >80% iliac vein occlusion. After thrombus removal, OCT revealed considerable venous intimal thickening and a small number of mural thrombi. Neointimal hyperplasia with thrombus formation was observed in all goats 1 week after stent implantation; the degree of ISR was 15%-33%. At 8 weeks, the degree of ISR was 21%-32% in 3 goats, and stent occlusion was observed in 1 goat. At 1 week, the neointima predominantly consisted of fresh thrombi. At 8 weeks, proliferplastic fibrotic tissue and smooth muscle cells (SMCs) were predominant, and the stent surfaces were endothelialized in 2 of 3 goats and partially endothelialized in 1 goat. CONCLUSIONS: In the goat model, postthrombotic neointimal hyperplasia in the venous stent may result from time-dependent thrombus formation and organization, accompanied by migration and proliferation of SMCs, causing ISR. These results provide a basis to further explore the mechanism of venous ISR and promote the development of venous stents that reduce neointimal hyperplasia.

Mechanism of effect of stenting on hemodynamics at iliac vein bifurcation.

When performing stent intervention for iliac vein compression syndrome, the operator selects the appropriate stent and determines its implantation depth according to the type and severity of iliac vein stenosis in the patient. However, there is still uncertainty regarding how the structure of the stent and its implantation depth affect hemodynamics at the site of lesion. In this paper, we analyzed three commonly used stents (Vena stent from Venmedtch, Venovo from Bard, and Smart stent from Cordis) with different implantation depths (0, 10, 20 mm) using computational fluid dynamics (CFD). We focused on evaluating hemorheological parameters such as time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), etc., within one pulsatile cycle after stent implantation. The correlation between geometric parameters of the stents and hemodynamic indicators was assessed using Pearson correlation coefficient (r), which was further validated through PIV velocity measurement experiment. The results revealed that an increase in implantation depth led to a more pronounced disturbance effect on blood flow at bifurcation for densely arranged support body-type stents. This effect was particularly significant during periods of smooth blood flow. On the other hand, crown-shaped Vena stents exhibited relatively less disruption to blood flow post-implantation. Implantation depth showed a strong negative correlation with TAWSS but a strong positive correlation with OSI and RRT. These findings suggest an increased risk of thrombosis at iliac vein bifurcation following stent placement. Amongst all three tested stents, Vena Stent demonstrated more favorable periodic parameters after implantation compared to others. These results provide valuable theoretical insights into understanding contralateral circulation thrombosis associated with iliac vein stenting.