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.

[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.

Iliac vein recanalisation and stenting accelerate healing of venous leg ulcers associated with severe venous outflow obstruction.

Obstruction involving the iliac veins and/or inferior vena cava is highly comorbid in patients with chronic venous leg ulcers and is a barrier to healing. Intervention with venous stenting is recommended to promote wound healing; however, there is limited data to quantify the effects of venous outflow restoration on wound healing. We retrospectively identified patients with venous ulcers and comorbid venous outflow obstruction. Data regarding demographics, wound size, degree of obstruction, interventions, wound healing and recurrence were collected. Intervention was performed when possible and patients were grouped based on whether or not the venous outflow was reopened successfully and maintained for at least 1 year. Outcomes, including time to wound healing, wound recurrence, stent patency and ulcer-free time, were measured. Patients who maintained a patent venous outflow tract experienced higher rates of wound healing (79.3%) compared to those with persistent outflow obstruction (22.6%) at 12 months (p < 0.001). Ulcer-free time for the first year was also greater with patent venous outflow (7.6 ± 4.4 months versus 1.8 ± 3.0 months, p < 0.0025). Patients with severe obstruction of the venous outflow tract experience poor healing of VLUs despite appropriate wound care. Healing time is improved and ulcer-free time increased after venous intervention with stenting to eliminate obstruction.

Impact of Common Iliac Vein Compression on the Incidence of Pulmonary Embolism in Patients with Acute Deep Vein Thrombosis.

OBJECTIVE: This study aimed to investigate the association between common iliac vein (CIV) compression and pulmonary embolism (PE) in lower extremity deep vein thrombosis (DVT). METHODS: This was a single centre retrospective study. Between January 2016 and December 2021, DVT patients with enhanced computed tomography of the iliac vein and pulmonary artery were included. Patient demographics, comorbidities, risk factors, and degree of CIV compression were collected and analysed. Logistic regression was performed to evaluate the odds ratio (OR) with a 95% confidence interval (CI) of PE in relation to compression severity groups. The association between PE and compression degree was evaluated with restricted cubic splines (RCS) based on an adjusted logistic regression model. RESULTS: Two hundred and twenty-six DVT patients (left side, n = 153; right side, n = 73) were included. Univariable analyses suggested that symptomatic or asymptomatic PE (54.4%, 123/226) was more common in men (p = .048) and right side DVT (p = .046) patients. Compared with no CIV compression, multivariable analyses suggested that mild compression did not statistically significantly reduce the PE risk, whereas moderate (adjusted OR 0.36; 95% CI 0.15 - 0.88; p = .025) and severe (adjusted OR 0.18; 95% CI 0.06 - 0.54; p = .002) compression statistically significantly reduced the risk. RCS showed that a smaller minimum diameter or greater compression percentage was correlated with continuously decreasing PE risk at a minimum diameter of < 6.77 mm or compression > 42.9%. CONCLUSION: PE is more common in men and right side DVT patients. An increasing severity of CIV compression is consistently associated with a decreasing risk of PE when the minimum diameter is < 6.77 mm or the compression is > 42.9%, indicating that it is a protective factor against PE.

Predictive Factors of Stent Patency in Iliofemoral Venous Diseases in a Multicentre Cohort Study.

OBJECTIVE: This study assessed primary stent patency predictive factors in three groups of patients with history of lower limb (LL) vein thrombosis: non-thrombotic iliac vein lesion (NIVL), acute deep vein thrombosis (aDVT), and post-thrombotic syndrome (PTS). METHODS: Consecutive patients from January 2014 to December 2020 with history of LL vein stenting from seven hospitals were included. All patients received an iliac or common femoral venous stent and had at least a six month follow up available with stent imaging. Anticoagulant and antiplatelet therapy strategies employed after venous stenting are reported and compared between groups. RESULTS: This study included 377 patients: 134 NIVL, 55 aDVT, and 188 PTS. Primary patency was statistically significantly higher in the NIVL group (99.3%) compared with the PTS group (68.6%) (p < .001) and the aDVT group (83.6%) (p = .002). PTS patients received a statistically significantly greater number of stents (p < .001) and had more stents below the inguinal ligament (p < .001). Median follow up was 28.8 months (IQR 16, 47). Discontinuation of antiplatelet therapy at the last assessment was 83.6% for NIVL, 100% for aDVT, and 95.7% for the PTS group (p < .001). Discontinuation of anticoagulation therapy at the last assessment was 93.2% for NIVL, 25.0% for aDVT, and 70.3% for the PTS group (p < .001). The only predictor of worse primary patency in the aDVT group was long term anticoagulation before stenting. CONCLUSION: Patients with NIVL have better primary patency after venous stenting than patients with venous thrombotic disorders. Long term anticoagulation before stenting was the only factor associated with poorer primary patency in patients with aDVT.

Diagnosis and Management of Pelvic Venous Disorders: AJR Expert Panel Narrative Review.

Pelvic venous disorders (PeVD), previously known by various imprecise terms including pelvic congestion syndrome, have historically been underdiagnosed as a cause of chronic pelvic pain (CPP), a significant health problem associated with reduced quality of life. However, progress in the field has helped to provide heightened clarity with respect to definitions relating to PeVD, and evolution in algorithms for PeVD workup and treatment has been accompanied by new insights into the causes of a pelvic venous reservoir and associated symptoms. Ovarian and pelvic vein embolization, as well as endovascular stenting of common iliac vein compression, should be considered as management options for PeVD. Both treatments have been shown to be safe and effective for patients with CPP of venous origin, regardless of age. Current therapeutic protocols for PeVD exhibit significant heterogeneity owing to limited prospective randomized data and evolving understanding of the factors driving successful outcomes; forthcoming clinical trials are anticipated to improve understanding of CPP of venous origin as well as algorithms for PeVD management. This Expert Panel Narrative Review provides a contemporary update relating to PeVD, summarizing the entity's current classification, diagnostic workup, endovascular treatments, management of persistent or recurrent symptoms, and future research directions.

Preprocedural imaging modalities in patients undergoing iliocaval venous recanalization and stent placement.

PURPOSE: To determine the diagnostic accuracy of preinterventional imaging modalities in patients being evaluated for iliocaval venous recanalization and stent placement. METHODS: Consecutive patients with iliocaval postthrombotic obstructions or nonthrombotic iliac vein lesions (NIVL), who were scheduled for recanalization, underwent duplex ultrasound (DUS), magnetic resonance venography (MRV), multiplanar venography (MPV), and intravascular ultrasound (IVUS). The diagnostic accuracies of DUS, MRV, and MPV were analyzed using IVUS as reference. RESULTS: A total of 216 limbs in 108 patients (80 patients with postthrombotic obstructions, 28 patients with NIVL) were examined. In patients with postthrombotic obstructions, the diagnostic sensitivities for the detection of lesions of the common femoral vein were 81% (95% CI 71-89%) for DUS, 76% (95% CI 65-85%) for MRV, and 86% (95% CI 76-93%) for MPV. The sensitivities for detecting lesions of the iliac veins were 96% (95% CI 89-99%) for DUS, 99% (95% CI 92-100%) for MRV, and 100% (95% CI 94-100%) for MPV. Regarding the inferior vena cava, the sensitivities were 44% (95% CI 24-65%) for DUS, 52% (95% CI 31-73%) for MRV, and 70% (95% CI 47-86%) for MPV. The sensitivities for detecting NIVL were 58% (95% CI 34-79%) for DUS, 90% (95% CI 68-97%) for MRV, and 95% (95% CI 73-99%) for MPV. CONCLUSION: In patients scheduled for recanalization of iliocaval postthrombotic obstructions, the sensitivities of DUS, MRV, and MPV were similar. In patients with suspected inferior vena cava involvement and in patients with NIVL, additional imaging with MR or conventional venography is required.

Spontaneous iliac vein rupture and thrombosis in patients with May-Thurner syndrome: A narrative review.

Spontaneous iliac vein rupture (SIVR) is extremely rare and can lead to serious complications, including death. Etiologies include inflammatory processes and hormonal and mechanical triggers, with concomitant May-Thurner syndrome (MTS) being a rare cause. Management can be challenging due to the difficult balance between reducing thrombotic burden and life-threatening hemorrhage that can result from aggressive anticoagulation. Furthermore, surgical interventions are associated with high mortality, making conservative management more desirable. We report a case of SIVR with retroperitoneal hematoma and concurrent MTS that was successfully managed using conservative measures. We further provide a narrative review of the current literature addressing the diagnosis, management, and outcome of SIVR focusing on cases with concurrent MTS.

Assessing outcomes after thrombectomy with or without iliac vein stenting for young provoked DVT patients with iliac vein stenosis.

BACKGROUND: This study aimed to assess the outcomes of thrombectomy with/without iliac vein stenting for young and transiently provoked DVT patients with iliac vein stenosis. METHODS: This is a retrospective analysis of a prospectively collected multicenter database. Acute, transiently provoked DVT patients between 18 and 45 years old with iliac vein stenosis were included. All patients underwent thrombectomy. Outcomes including the Villalta score, the VEINES-QOL score, and adverse events were evaluated. RESULTS: The data of 522 patients were collected of whom 75 were included, 58 underwent thrombectomy alone (nonstenting group) and 17 underwent thrombectomy and stenting (stenting group). Within 6 months, the Villalta score of patients in stenting group is lower than that of patients in nonstenting group (6 mo: 0.73 ± 0.77 vs. 1.41 ± 0.56, p = .0004), and the VEINES-QOL score of stenting group is higher than that of nonstenting group (6 mo: 89.00 ± 2.94 vs. 87.47 ± 3.72, p = .2141). At the following follow-ups, the Villalta score (12 mo: 0.56 ± 0.49 vs. 0.60 ± 0.58, p = .8266) and VEINES-QOL score (12 mo: 88.36 ± 2.29 vs. 88.31 ± 3.36, p = .9604) between the two groups are similar. CONCLUSION: The stenting group had better efficacy within 6 months after intervention, while there was no significant difference in the symptom, signs, and quality of life between two groups after 6 months within a 2-year follow-up. TRIAL REGISTRATION: This study was registered in the Chinese Clinical Trial Registry (Registration Number: ChiCTR2200056073).

Anatomy of the internal iliac vein around the sacral promontory based on CT three-dimensional (3D) reconstruction.

INTRODUCTION AND HYPOTHESIS: The area around the sacral promontory (SP) is the targeted location of various pelvic operations. We examined the internal iliac vein (IIV) configurations around the SP by computed tomography angiography (CTA) three-dimensional (3D) reconstruction to describe its anatomy and provide accurate anatomical parameters for relevant operations to reduce intraoperative vascular injury. METHODS: We retrospectively studied 2078 CTA 3D model datasets from Nanfang Hospital patients examined for gynecological diseases from December 2009 to October 2020. The IIVs of the above cases were divided into standard and variant IIVs, and variant IIVs were subdivided into different subtypes. To compare the size of the avascular area around the SP between standard and variant IIVs, we selected the two subtypes with the highest variation rate for comparison with the standard IIV type. RESULTS: The most common types of variant IIVs were 5a (5.15%) and 3a (5.05%). The results showed larger values in the standard group than in the 3a and 5a groups for the confluence of common iliac vein (CCIV) height (37.73±12.05 vs. 28.93±10.17 vs. 27.27±7.58 mm, P < 0.05), distance between the iliac vessels (49.47±9.47 mm vs. 37.08±9.36 vs. 37.73±8.94 mm, P < 0.05), and SP exposure width (44.94±6.39 mm vs. 36.83±8.29 vs. 36.93±7.91, P < 0.05). CONCLUSIONS: Variant IIVs may increase the risk of surgery by reducing the avascular area compared with standard IIVs. Therefore, when operating around the SP, special attention should be given to variant IIVs and avoiding vascular injury.

Accurate diagnosis of isolated iliac vein thrombosis in third trimester pregnancy with clues on great saphenous vein reflux: a case report and review of literature.

BACKGROUND: Pregnancy is known to be a risk factor for venous thromboembolism (VTE). We report the case of a pregnant patient with difficult to diagnose iliac vein thrombosis, establishing a definite diagnosis by clues of great saphenous vein reflux. CASE PRESENTATION: A 37-year-old G1P0 woman at 35 weeks of assisted twin gestation presented with a complaint of persistent left lower limb edema and tenderness. A vascular ultrasound was used to examine the bilateral lower limb. Doppler of left lower extremity revealed continuous great saphenous vein reflux. Right saphenofemoral veins demonstrated venous stasis and no reflux. Unilateral continuous great saphenous vein reflux suggested left iliac veins obstruction or extrinsic compression. Anterograde venography showed a completely occlusive filling defect of the left external iliac vein, which is the definitive diagnosis of acute deep venous thrombosis. The patient underwent a cesarean delivery following inferior vena cava filter (IVCF) placement, and no signs of deep venous thrombosis (DVT) or pulmonary embolism (PE) were reported after delivery. CONCLUSION: In pregnant women with suspected deep vein thrombosis, it is imperative to assess the presence of unilateral continuous great saphenous vein reflux.

Impact of stent compression in patients with non-thrombotic iliac vein lesions on iliac vein blood flow and related symptoms.

OBJECTIVES: To study outcomes in patients with non-thrombotic iliac vein lesions (NIVLs) treated by stents. METHODS: We performed a retrospective study that collected 109 patients from January 2016 to August 2020 diagnosed with symptomatic NIVLs. The patients underwent endovenous stenting using the Wallstents. Clinical severity was assessed using the venous clinical severity score and the Villalta scores. The patency was assessed using duplex ultrasound, while the diameters and the blood flow velocities (BFVs) in the proximal, middle, and distal stented segments were recorded simultaneously. RESULTS: A total of 128 stents were placed in 115 limbs (median age, 61 years), with a mean follow-up of 32 months. At 36 months, the Villalta scores went from 12.17 to 3.64 (p < .001). The VCSS went from 9.41 to 3.31 (p < .001). The mean diameters in the proximal, middle, and distal stented segments were 8.52 ± 2.15 mm, 10.13 ± 1.75 mm, and 10.17 ± 1.69 mm in the first month, while the mean BFVs were 31.17 ± 13.66 cm/s, 31.07 ± 11.90 cm/s, and 36.39 ± 18.41 cm/s, respectively. Repeated-measures analysis in 55 consecutive patients from 1 month to 3 years after procedure revealed a decrease of the stent diameter in the proximal stented segment (p = .004); a stabilization of the stent diameter in the middle (p = .43) or distal (p = .45) stented segment; a steadiness of the BFVs in the proximal (p = .40), middle (p = .93), and distal (p = .25) stented segments; and an improvement in the VCSS (p = .03) and Villalta scores (p = .006). CONCLUSIONS: BFVs in stented segments remained steady and the symptoms in lower extremities improved after surgery, while stent compression was observed in the diameter of the proximal stented segment, with no impact on BFVs or symptoms.

Iliac vein compression syndrome by lumbar degenerative changes is associated with deep vein thrombosis after total knee arthroplasty.

INTRODUCTION: This study aimed to identify whether iliac vein compression syndrome(IVCS) is associated with deep vein thrombosis(DVT) after total knee arthroplasty(TKA) and whether lower lumbar degenerative changes were risk factors for IVCS. MATERIALS AND METHODS: A total of 259 consecutive patients who underwent TKA from January 2019 to March 2022 was retrospectively reviewed. Preoperative plain radiographs of lumbar spines and CT venography (CTV) for DVT diagnosis at postoperative 7 days were performed in all patients. Imaging findings of lower lumbar degenerative changes were analyzed on plain radiograph including lateral osteophytes, scoliosis, lateralolisthesis, retrolisthesis, anterolisthesis, and lower lumbar lordosis angle (LLLA). Percent compression at the left common iliac vein (LCIV) and right common iliac vein (RCIV) as well as DVT were evaluated on CTV. Moreover, IVCS was defined as greater than 50% of compression of the iliac vein on CTV. RESULTS: DVT occurred in 79 patients (30.5%) after TKA. The overall occurrence of DVT was significantly higher in patients with IVCS of LCIV (52.8%) than those without (18.8%, P < 0.001). When DVT was further subdivided, compared to non-IVCS, IVCS of LCIV was significantly associated with bilateral DVT (P < 0.001, both), especially distal DVT (P < 0.001, both), and IVCS of RCIV was significantly associated with right-side DVT (P = 0.031), especially popliteal (P = 0.008) and distal DVT(P = 0.011). Female patients (OR: 3.945, P = 0.039), presence of left osteophyte (OR: 2.348, P = 0.006), and higher LLLA (OR: 1.082, P < 0.001) were significantly associated with IVCS of LCIV, and presence of right osteophyte (OR: 3.494, P = 0.017) was significantly associated with IVCS of RCIV. CONCLUSION: IVCS was significantly associated with DVT after TKA and lumbar degenerative changes with lateral osteophytes and hyperlordosis were significant risk factors for IVCS.

Right iliac arteriovenous fistula due to aneurysm rupture and left iliac artery aneurysm: hybrid treatment.

An arteriovenous fistula (AVF) is an uncommon sequela of spontaneous arterial aneurysm rupture into the adjacent venous system. We describe the case of a 74-year-old patient who underwent endovascular treatment of a right iliac AVF caused by a ruptured common iliac artery (CIA) aneurysm and a distal left CIA aneurysm. Surgery preserved the lumbar and inferior mesenteric arteries because of the need to simultaneously exclude the hypogastric arteries. Dynamic fluid balance phenomena provoked by closure of the AVF are described. The patient had a benign postoperative course with normalization of the severe hemodynamic changes presented prior to the intervention and resolution of respiratory symptoms attributed to pulmonary arterial hypertension.

Deep venous thrombosis of the contralateral iliac vein after stenting of the iliocaval confluence: a therapeutic challenge.

The treatment of choice for patients with symptomatic venous compression syndrome is venous stenting. However, this treatment has well-documented complications and, although rare, contralateral deep venous thrombosis is one of these complications. Our objective is to present a case of deep venous thrombosis of the contralateral iliac vein resulting from placement of the stent beyond the recommended position and the therapeutic challenge is to recanalize the vein with reconstruction of the iliocaval confluence.

Morphometric and Hemodynamic Analysis of the Compressed Iliac Vein.

PURPOSE: To investigate the relationship between the morphological structure and hemodynamic properties of the compressed iliac vein and explore the reason for the formation of thrombosis in the compressed iliac vein. MATERIALS AND METHODS: A total of 11 patients with iliac vein compression syndrome (IVCS) were included in this study, and their iliac veins were reconstructed in 3 dimensions (3D). The morphological structures of the iliac veins (confluence angle, degree of stenosis) were analyzed based on the 3D model. Variations in the hemodynamic properties of the iliac vein were investigated at 4 typical moments in one cardiac cycle, and the relationship between the different morphological configurations and the pressure difference was investigated. RESULTS: In the region of the compressed iliac vein, the blood flow velocity is accelerated and the pressure changes abruptly accompanied by the increase in pressure difference. Higher time averaged wall shear stress (TAWSS) and lower relative residence time (RRT) appeared in stenosis regions of compressed iliac vein, while TAWSS was low and RRT was large near the stenosis position. There was a strong positive correlation between the degree of stenosis and the pressure difference (r=0.894), and a positive correlation between the confluence angle of the iliac vein and the pressure difference (r=0.638). CONCLUSION: The morphological structure of the compressed iliac vein has an obvious influence on the hemodynamic surroundings; the pressure difference becomes larger when the degree of stenosis and the confluence angle increase. The iliac vein luminal areas with low TAWSS and high RRT near the compressed location can impede blood flow and lead to accumulation of blood components, which may increase the risk of thrombosis formation and should be fully considered in the treatment of IVCS.

Editor's Choice - Clinical Efficacy of Venastent - A Novel Iliac Vein Stent for Non-Thrombotic Iliac Vein Lesions: A Multi-Centre Randomised Controlled Trial.

OBJECTIVE: To determine the efficacy of Venastent - a novel iliac vein stent for non-thrombotic iliac vein lesions (NIVLs). METHODS: From October 2018 to January 2021, 256 NIVL patients were recruited at 19 Chinese hospitals. A randomised controlled trial was conducted to compare the efficacy of the new iliac vein stent-Venastent (Tianhong China) with Zilver stent (Cook USA). All patients were allocated randomly to two groups: the experimental group patients used Venastent, while the control group received the Zilver stent. The trial was registered in Chinese Clinical Trial Registry (ChiCTR2200057851). RESULTS: A total of 123 patients in the experimental group and 122 patients in the control group had a full set of data collected (p = ns). The technical success rate was 100% (n = 245/245). The patency rate was 100% (n = 123/123) in the experimental group and 98.4% (n = 120/122) in control group one year after operation (p = ns). The lower extremity swelling remission rate was 79.1% (n = 87/110) in the experimental group and 78.4% (n = 91/116) in the control group (p = ns). The lower extremity pain relief rate was 68.8% (n = 50/80) in the experimental group and 77.2% (n = 71/92) in the control group (p = ns). The ulcer healing rate was 90% (n = 18/20) in the experimental group and 87% (n = 20/23) in the control group (p = ns). There was no difference in stent re-stenosis or clinical remission between the two groups. CONCLUSION: The new iliac vein stent, Venastent, had a comparable high patency rate and safety profile as the Zilver stent (Cook) in NIVLs patients. Venastent significantly reduced symptoms of chronic venous disease.

Performance of Open and Closed Cell Laser Cut Nitinol Stents for the Treatment of Chronic Iliofemoral Venous Outflow Obstruction in Patients Treated at a Single Centre.

OBJECTIVE: A number of dedicated self expanding nitinol stents have been developed for use in the venous system, with both open cell (OC) and closed cell (CC) designs available. Data comparing these different designs are lacking. The objective of this study was to evaluate outcomes in patients treated with open and closed cells for unilateral chronic iliac vein obstruction. METHODS: A single centre retrospective cohort study was conducted, including all patients treated with a dedicated nitinol venous stent between 2014 and 2019. Stent patency and details of re-interventions (including lysis, venoplasty, reinforcement, extension, arteriovenous fistula formation) were examined in the first post-operative year. Subgroup analysis described outcomes for patients treated with OC and CC stents ending above the inguinal ligament and those who required extension into the common femoral vein. Cox regression analysis was used to identify factors associated with loss of primary patency. RESULTS: A total of 207 patients were included (OC 100 patients, CC 107 patients). There was no significant difference between the groups for age (OC 42 years, CC 44 years); gender (OC and CC 67% female); presence of post-thrombotic lesions (OC 71%, CC 73%); stenting across the inguinal ligament (OC 58%, CC 56%), or presence of inflow disease (OC 49%, CC 47%). Primary and cumulative patency at 12 months were similar between groups (primary: OC 63%, CC 65%; cumulative: OC 93%, CC 90%). Patients with a CC stent across the inguinal ligament had a greater risk of needing multiple re-interventions at one year compared with those with an OC stent (odds ratio 2.84, 95% confidence interval [CI] 1.16 - 6.9) but overall, the only factor significantly associated with loss of primary patency was inflow vessel disease (hazard ratio 3.39, 95% CI 1.73 - 6.62, p < .001). CONCLUSION: OC and CC dedicated nitinol venous stents were observed to perform similarly in terms of patency and symptom improvement at one year. Disease of the inflow vessels was the most important factor associated with a loss of stent patency irrespective of stent design.

A Systematic Review on the Incidence of Stent Migration in the Treatment of Acute and Chronic Iliofemoral Disease Using Dedicated Venous Stents.

OBJECTIVES: This systematic review investigated the incidence of stent migration in patients with acute and chronic deep venous iliofemoral disease who were treated with dedicated venous stents. Procedural approaches, clinical and stent patency outcomes, and other complications are described. METHODS: MEDLINE and Embase were searched for literature published from January, 2012 to December, 2021. Evidence on the study population and procedural characteristics, and outcomes related to symptomatic changes, health-related quality of life, stent patency and complications was presented. RESULTS: Fourty-two studies were identified from 857 articles found through the database searches. Five-hundred seventy acute deep vein thrombosis patients and 2,859 chronic disease patients were included. Ten dedicated venous stent brands were employed. There were six episodes of stent migration (0.17% of patients) of which three involved a closed-cell stent and one involved a hybrid-design stent. The 12-month primary patency rate in patients with acute deep vein thrombosis ranged from 86 to 88%, whilst secondary patency was 96%. Amongst the chronic-disease cohort the primary and secondary patency were noted to range from 59 to 94%, and 87 to 100%, respectively. The pooled 12-month primary and secondary stent patency rates were 73.8% and 91.5%, respectively. CONCLUSIONS: Iliofemoral stenting using dedicated venous stents is associated with a low rate of stent migration although this may be due to a lack of reporting. Further research with specific surveillance protocols is necessary to reliably determine the true incidence of stent migration.

Successful treatment of acquired arteriovenous fistula following iliac vein thrombosis.

OBJECTIVES: Cases of arteriovenous fistula following iliac vein thrombosis are uncommon. The pathogenesis of its formation remains unclear. We present the efficacy of left common iliac vein recanalization in acquired arteriovenous fistula treatment. METHODS: A 71-year-old man presented with severe lower left limb edema and was diagnosed with acquired arteriovenous fistula following iliac vein thrombosis. Treatment by recanalizing the left common iliac vein with bare stents was selected over embolizing the arteriovenous fistula, leading to an excellent clinical outcome.Results and Conclusions: Acquired arteriovenous fistula should be considered in some patients with post-thrombotic syndrome. Endovascular recanalization without embolization of the arteriovenous fistula can effectively treat iliac vein thrombosis associated with arteriovenous fistula.