Total Endovascular Repair of a Giant Iliac Vein Aneurysm: A Case Report and Review of Literature.

PURPOSE: The iliac veins are the least frequent location for venous aneurysms, with only a few cases described globally. The etiology and clinical presentation of this extremely rare entity is diverse and unclear and no treatment consensus has been reached yet. Our purpose is to present an interesting iliac vein aneurysm (IVA) case that we treated in our department, with a brief review of the literature. CASE REPORT: We report a case of a 74-year-old male patient with a giant, 55 mm in diameter, asymptomatic, right common IVA, with concurrent aplasia of the left common iliac vein and an extensive network of venous collaterals. The patient was treated, under general anesthesia, with total endovascular iliocaval reconstruction through implantation of a 32 × 100 mm thoracic aortic tubular Ankura stent graft. The computed tomography venography at first-month follow-up showed the complete exclusion of the IVA, without any endoleak and the patient remains up to date free of symptoms and thromboembolic events. CONCLUSION: Twelve cases of endovascular treatment of IVA have been reported so far, and our case is the first with implantation of a thoracic aortic stent graft. Our results suggest that this technique is safe, effective, and may be considered for appropriately selected patients. CLINICAL IMPACT: This is the first case with total endovascular repair of an iliac vein aneurysm with contralateral iliac vein aplasia through endovenous implantation of a thoracic aortic stent-graft. Our results suggest that this technique is safe and effective and thus, may be considered for appropriately selected cases.

Prospective Cohort Study of a Treatment Strategy for a Combination of the Left Common Iliac Vein Compression Stenosis and Pelvic Venous Insufficiency.

PURPOSE: To develop a strategy for the iliac vein stenting in patients with a combination of the left common iliac vein (LCIV) compression stenosis and pelvic venous insufficiency (PVI). METHODS: This prospective comparative cohort study included 55 patients with hemodynamically significant LCIV stenosis out of 285 females with PVI screened in 2014-2022. All 55 patients underwent duplex ultrasound, multi-detector computed venography, ovarian venography, and multiplanar pelvic venography. Patients underwent LCIV stenting or the left gonadal vein (LGV) embolization as the primary intervention. The endpoints (chronic pelvic pain [CPP] relief, patency of stents, and reduction in pelvic venous reflux [PVR]) were evaluated 1 and 10 days, as well as 1, 6, and 12 months after the procedure. All patients received antithrombotic therapy after the interventions. RESULTS: The primary LCIV stenting was performed in 49 patients and resulted in the CPP relief in 69.4%, pain reduction from 7.9±1.3 to 1.7±1.1 visual analog scale (VAS) scores (p=0.005), and substantial reduction of PVR in LGV (from 4.3±0.6 seconds to 1.9±0.3 seconds, p=0.003). The LGV embolization as the second stage of treatment was performed in 30.6% of patients with the LGV reflux greater than 5 seconds as a possible cause for the CPP persistence. The primary LGV embolization failed in 100% of patients (no changes in CPP and PVR). The LCIV stenting at the second stage resulted in the CPP relief within 10 days and the pelvic venous reflux (PVR) reduction. There were no complications of stenting, and the patency of stents in the follow-up period was 100%. Postembolization syndrome occurred in 9.5% of patients. No thromboses of the veins of the pelvis and lower extremities were identified. CONCLUSION: Treatment of patients with a combination of LCIV compression and PVI involves staged endovascular interventions: the LCIV stenting should be considered the first-line treatment, while the LGV embolization is performed when the PVI symptoms persist for more than 6 months and is not acceptable as the first-line treatment. CLINICAL IMPACT: The developed strategy of endovascular treatment for the combination of left common iliac vein (LCIV) and pelvic venous insufficiency (PVI) provides an effective elimination of chronic pelvic pain (CPP) and reflux in the pelvic veins and avoids unnecessary embolizations of the gonadal veins, thereby eliminating possible risks related to complications of embolization. The use of antithrombotic therapy is an effective and safe approach for preventing venous thromboembolic events after endovascular interventions.

[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.

A cadaver study evaluating intraluminal anomalies of the left common iliac vein.

OBJECTIVE: Intraluminal anomalies within the left common iliac vein, characteristic of iliac vein compression syndrome, are thought to result from compression by and pulsation of the overlying right common iliac artery. This cadaver study was designed to expand on the existing literature by surveying and photographing these spurs in addition to exploring whether certain factors, inherent to the cadaver, are associated with spur presence. METHODS: Dissection to expose the aorta, inferior vena cava, and common iliac arteries and veins was performed in 51 cadavers. The spinal level at which the iliac vein confluence occurred was noted. The point at which the right common iliac artery crossed the left common iliac vein was examined for plaque presence. The overlying arterial structures were then transected to expose the venous system. The inferior vena cava was incised to facilitate observation into the mouth and full extent of the left common iliac vein. Spurs were photographed and documented. Statistical analysis was conducted to determine whether sex, body mass index (BMI), plaque presence, or level of the iliac vein confluence are associated with spur presence. RESULTS: Spurs within the left common iliac vein were observed in 16 of 51 cadavers (31.4%). All spurs were located at the point that the right common iliac artery crossed the left common iliac vein. Using1 the classification system established by McMurrich, 67% of spurs (n = 10) were marginal and triangular; 25% (n = 4) were columnar. One marginal, linear spur (6%) and one partially obstructed spur with multiple synechiae (6%) were observed. Among this population, males were 73% less likely to have a spur (odds ratio, 0.269; P = .041). No significant relationship was found between plaque presence and spur presence (odds ratio, 0.933; P = .824) and no significant differences were noted between BMI and spur presence (χ2 = 1.752, P = .625). Last, a significantly greater percent of spurs was found within cadavers with an iliac vein confluence located at the L5/S1 disc space (χ2 = 9.650; P = .002). CONCLUSIONS: Study findings show that spurs are more common when the confluence of the common iliac veins occurs at a lower spinal level. The level of the iliac vein confluence may be important in identifying patients at increased risk of venous disease. The findings also suggest that plaque within the right common iliac artery and BMI display no distinct relationship with spur presence. Further investigation is needed to understand exactly what factors lead to spur formation.

Risk factors for low back pain after iliac vein stenting for non-thrombotic iliac vein lesions.

OBJECTIVE: Iliac vein stenting is an option being explored to treat chronic venous insufficiency. We have noted that our most common postoperative complication is low back pain after stent placement, which is occasionally quite severe. We wanted to investigate risk factors that are involved in this phenomenon and identify potentially modifiable factors. METHODS: Patients who failed 3 months of conservative therapy had iliac vein interrogation performed. We limited the scope of this database to non-thrombotic iliac vein lesions treated in the office in which Wallstents were placed. Data were collected from September 2012 to August 2020 for 2308 consecutive outpatients who underwent 3747 procedures. Before August 2016, patients received pre-procedure oral valium (n = 2679) and thereafter, patients received intravenous (IV) sedation (n = 1068). A pain score, on a Likert scale ranging from 0 to 10, was assessed within 1 hour postoperatively. We analyzed the medications administered and correlated them with pain scores. RESULTS: The average of all the pain scores was 0.86 (range, 0-10; standard deviation [SD], 2.00). Age had a slight inverse effect on pain scores (r = -0.12; P < .00001). Presenting signs (based upon CEAP) (P = .11) and body mass index (P = .88) did not have a significant effect on pain scores. Average pain score for females (0.96) was slightly higher than for males (0.70), with P < .0001. Average pain score for procedures on the right side (0.67) was lower than for procedures on the left side (1.01), with P < .0001. Average pain score for patients who received IV sedation (mean, 0.68; SD, 1.58) was lower than that for those who did not (mean, 0.93; SD, 2.15), with P = .0004. When using a single agent, propofol was associated with the lowest pain scores (P < .0001). Toradol displayed a dose-dependent effect on pain score (P < .0001). The best combination of agents for pain control was propofol and toradol together. CONCLUSIONS: Overall, the vast majority of pain scores were low. Factors that were associated with lower pain scores were older age, male sex, procedures on the right side, and IV sedation, in particular with the use of propofol. These data may help us better target patients anticipated to have high pain scores and suggest the preferential use of propofol and toradol.

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.

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.

Right-sided iliac vein compression syndrome: when the vein is compressed between the internal and external iliac arteries-a case report.

Background: In its normal anatomical relationship, the inferior vena cava is located on the right side of the abdominal aorta. Iliac vein compression syndrome (IVCS) is a pathological condition in which a blood clot is formed due to blood flow obstruction when the left common iliac vein is compressed between the right common iliac artery and the vertebral body. Therefore, right-sided IVCS (RIVCS) is rare. The effectiveness of treatment for RIVCS has not been sufficiently investigated. Case summary: A 51-year-old man developed deep vein thrombosis in the right lower extremity and non-massive pulmonary embolism during steroid treatment for IgA nephropathy. Magnetic resonance angiography (MRA) suggested iliac compression syndrome. Symptoms improved with the use of direct oral anticoagulants and compression stockings. At the 8-month follow-up, the clinical course was uneventful. Discussion: The causes of RIVCS in this case are believed to be the effects of steroids, prolonged sitting, and compression of the right external iliac vein. However, considering that deep vein thrombosis did not form in the left lower limb where there was no venous compression, it can be considered that the compression of the right external iliac vein had a significant impact. This case has been followed up for 8 months with anticoagulants and is progressing well. This is the first case to report the course of RIVCS treated conservatively with anticoagulant therapy for 8 months. This case suggested that conservative treatment is effective for RIVCS.

Diagnosis of chronic iliac venous obstruction.

Stenting has become the first line of treatment for symptomatic chronic iliofemoral venous obstruction in patients with quality-of-life-impairing clinical manifestations who have failed conservative therapy. Patient selection for such intervention is, however, dependent on clear identification of relevant clinical manifestations and subsequent testing to confirm the diagnosis. In this regard, the physician engaged in management of such patients needs to be well-aware of symptoms and signs of chronic iliofemoral venous obstruction, and instruments used to grade chronic venous insufficiency and determine quality of life, in addition to diagnostic tests available and their individual roles. This review serves to provide an overview of the diagnosis of chronic iliofemoral venous obstruction and patient selection for stenting.

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

PURPOSE: To report technical feasibility and clinical efficacy of iliac vein stent placement in adolescent patients with May-Thurner Syndrome (MTS). MATERIALS AND METHODS: Single-institution retrospective review of the medical record between 2014 and 2021 found 63 symptomatic patients (F = 40/63; mean age 16.1 years, 12-20 years) who underwent left common iliac vein (LCIV) stent placement for treatment of LCIV compression from an overriding right common iliac artery, or equivalent (n = 1, left IVC). 32/63 (50.7%) patients presented with non-thrombotic iliac vein lesions (NIVL). 31/63 (49.2%) patients presented with deep vein thrombosis of the lower extremity and required catheter-directed thrombolysis after stent placement (tMTS). Outcomes include technically successful stent placement with resolution of anatomic compression and symptom improvement. Stent patency was monitored with Kaplan-Meier analysis at 3, 6, 12, 24, and 36 months. Anticoagulation and antiplatelet (AC/AP) regimens were reported. RESULTS: Technical success rate was 98.4%. 74 bare-metal self-expanding stents were placed in 63 patients. Primary patency at 12, and 24-months was 93.5%, and 88.9% for the NIVL group and 84.4% and 84.4% for the tMTS group for the same period. Overall patency for the same time intervals was 100%, and 95.4% for the NIVL group and 96.9%, and 96.9% for the tMTS group. Procedural complication rate was 3.2% (2/63) with no thrombolysis-related bleeding complications. Clinical success was achieved in 30/32 (93.8%) and 29/31 (93.5%) patients with tMTS and NIVL groups, respectively. CONCLUSION: CIV stent placement in the setting of tMTS and NIVL is technically feasible and clinically efficacious in young patients with excellent patency rates and a favorable safety profile.

Spontaneous ilio-iliac arteriovenous fistula: A rare complication of aorto-iliac aneurysm.

Ilio-iliac arteriovenous fistula is an unusual complication of aorto-iliac aneurysms that can occur spontaneously, traumatically or iatrogenically. The typical clinical presentation includes the characteristic triad of high-output heart failure, a pulsatile abdominal mass with unilateral limb ischemia, or signs of venous congestion. We describe a rare case of spontaneous rupture of an aortoiliac aneurysm into the left common iliac vein of a 65-year-old man, easily diagnosed by angiography. We highlight here the angiographic findings of the ilio-iliac fistula, which was the means of diagnosis in this presentation, especially in patients with atypical clinical features at the outset, and we report the difficulties in choosing the optimal vascular approach.

A Suspected Case of Adhesion to the Iliac Vein During the Left Femoral Arthroplasty.

An 85-year-old man underwent hemiarthroplasty for a left intertrochanteric femoral fracture at another hospital two years prior. While under outpatient monitoring, the left femur displacement occurred. Therefore, total hip arthroplasty of the left hip was scheduled. However, during acetabular cup insertion damage to the inner plate led to a sudden decrease in blood pressure from 120 to 60 mmHg. The physicians suspected a pelvic vascular injury and promptly stopped the procedure. In case of adhesion between the acetabular cup and the left iliac vein, intraoperative vascular damage would be repaired via endovascular intervention. Subsequently, orthopedic surgery was cautiously performed, taking into account the potential of a vascular injury. The surgery proceeded as planned without vascular intervention. This case involved a patient with suspected injury to the iliac vein and artery during acetabular cup placement. Following comprehensive enhanced CT and angiography tests, orthopedic surgery was performed in preparation for potential vascular damage, demonstrating the multidisciplinary approach to managing such cases.

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.

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.

Consensus Statement on the Management of Nonthrombotic Iliac Vein Lesions From the VIVA Foundation, the American Venous Forum, and the American Vein and Lymphatic Society.

A nonthrombotic iliac vein lesion is defined as the extrinsic compression of the iliac vein. Symptoms of lower extremity chronic venous insufficiency or pelvic venous disease can develop secondary to nonthrombotic iliac vein lesion. Anatomic compression has been observed in both symptomatic and asymptomatic patients. Causative factors that lead to symptomatic manifestations remain unclear. To provide guidance for providers treating patients with nonthrombotic iliac vein lesion, the VIVA Foundation convened a multidisciplinary group of leaders in venous disease management with representatives from the American Venous Forum and the American Vein and Lymphatic Society. Consensus statements regarding nonthrombotic iliac vein lesions were drafted by the participants to address patient selection, imaging for diagnosis, technical considerations for stent placement, postprocedure management, and future research/educational needs.

Acetabular and pelvic fracture repair complicated by phlegmasia cerulea dolens: A report of limb salvage with open thrombectomy and modified Palma procedure.

A 57-year-old man presented after a fall, which resulted in acetabular and pelvic fractures. He underwent fracture fixation, which was complicated by iliac vein occlusion, leading to phlegmasia cerulea dolens. He underwent lower extremity surgical venous thrombectomy, contralateral iliac vein stent placement, and modified Palma procedure with an expanded polytetrafluoroethylene venous crossover bypass and arteriovenous fistula creation. His postoperative course was unremarkable and he regained full function of the extremity without significant stasis complications. The bypass and stent remain patent 3 years postoperatively. Although iliac vein injury during acetabular fracture repair is rare, prompt recognition and intervention prevent limb loss.

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

BACKGROUND: Iliofemoral venous stent placement (IVS) has evolved to a well-established endovascular treatment modality for chronic iliofemoral venous obstruction (CIVO). Dedicated venous stents gained approval from the US Food and Drug Administration in 2019 and solidified IVS as a defined intervention with clear indications, contraindications, risks, benefits, and procedural management principles. This review focuses on the indications, technical aspects and outcomes of stenting for CIVO. Other aspects pertaining to IVS are covered in other articles that are a part of this series. METHODS: This study conducted a literature search limited to English articles. Three search strategies were used, and references were managed in Covidence software. Four investigators screened and evaluated articles independently, excluding meta-analyses, clinical trial protocols, and nonrelevant studies. Eligible studies, focused on clinical outcomes and stent patencies, underwent thorough review. RESULTS: The literature search yielded 1704 studies, with 147 meeting eligibility criteria after screening and evaluation. Exclusions were based on duplicates, irrelevant content, and noniliac vein stent placement. CONCLUSIONS: Successful IVS for CIVO relies on meticulous patient selection, consistent use of intravascular ultrasound examination during procedures and attention to the technical details of IVS.

Sutureless Repair for Iliac Vein Bleeding Using an Elastomeric Sealant.

Addressing venous bleeding is a frequent complication of vascular and abdominopelvic surgeries. We present a novel sutureless repair technique using HydrofitⓇ (Terumo, Tokyo, Japan), an elastomeric sealant. In a patient experiencing common iliac vein bleeding during abdominal aortic aneurysm surgery, this technique successfully achieved complete hemostasis. By applying the elastomeric sealant with an autologous arterial patch to the bleeding site, we demonstrate the simplicity and effectiveness of sutureless hemostasis for venous bleeding.

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.

Treating Chronic Iliac Vein Stent Occlusion in an Office-Based Lab Setting.

Iliac vein stenting is performed when sufficient venous patency is not achieved via angioplasty or lysis. Iliac vein stenting is known to be effective; however, occlusion of the stent occurs occasionally. There is a lack of effective treatment options for those with failed prior venous stents, and traditional methods may involve the removal of the stent and surgical reconstruction. We present a patient with a right leg post-thrombotic syndrome and narcotic abuse after occlusion of a previously placed right common iliac/external iliac vein stent 25 years prior. After transfer to an office-based lab (OBL), femoral vein access was achieved. Then, a second stent was deployed adjacent to the previously chronically thrombosed stent. Imaging confirmed adequate deployment of the new stent and venous flow. Treatment resulted in a significant decrease in patient pain and cessation of narcotics. We demonstrate successful recanalization of a right iliac vein thrombosis via parallel deployment of a stent adjacent to a chronically thrombosed stent.