Iliac Vein Stenting Research Articles

Obstruction or reflux as the primary problem in pelvic congestion syndrome

The authors performed a retrospective review of patients treated for pelvic congestion syndrome (PCS) with isolated iliac vein stenting, without any direct treatment/embolization of the pelvic varicosities to determine whether this approach might yield good results.1 With isolated iliac vein interventions, the authors found that they had complete symptom resolution in 76% of patients at 6-month follow-up; however, seven patients did require additional interventions (two of these having only undergone venoplasty without stent at the initial procedure).

Contralateral Deep-Vein Thrombosis in Lliac Vein Stenting – Incidence, Etiology, and Prevention

Iliocaval venous obstruction is a significant contributor to venous hypertension. Recanalization and stenting of chronic deep venous obstructions are minimally invasive and have been proven to be safe and effective with low complication rates over the past few decades. Common iliac vein (CIV) stents are usually extended into the inferior vena cava (IVC) to some extent to ensure adequately that key areas of stenosis are adequately treated. This may lead to contralateral CIV jailing and increase the risk of contralateral deep-vein thrombosis (DVT). The reported incidence of contralateral DVT after CIV stent placement from different studies varies from 1% to 15.6%. The predicted risk factors are noncompliance with anticoagulation, underestimation of the postthrombotic venous disease, preexisting IVC filter, incorrect stent placement, preexisting contralateral internal iliac vein thrombosis, malignancy, and thrombophilia. Literature suggests that the use of intravascular ultrasound, newer dedicated stents, and Z-stent modification reduces the incidence of contralateral DVT. Precise stent deployment technique and proper attention to other hematological risk factors are the key to preventing this complication. This article will review the incidence, mechanism, risk factors, and technical aspects of how to avoid this unfortunate complication. We will also review the newer dedicated venous stents.

Iliac vein stenting is safe when performed in an office based laboratory setting

BackgroundVenous stenting for iliac vein outflow obstruction is associated with excellent long-term stent patency and symptom resolution. However, the safety of iliac vein stenting performed in an office-based laboratory (OBL) setting is not well-defined. The purpose of our investigation was to determine the safety profile of iliac vein stenting in an OBL setting. MethodsData were prospectively collected in the Center for Vascular Medicine electronic medical record system (NextGen Healthcare Information System, Irvine, Calif) and retrospectively analyzed. Standardized patient safety and sedation protocols were used in accordance with the accreditation standards of the Joint Commission for Accreditation of Hospital Organizations for office-based surgery centers. Patient consultations, interventions, and follow-up at 1 to 6 weeks were included in the present analysis. All the patients had received moderate sedation during their procedure. Complications requiring hospitalization were classified as major complications. Minor complications consisted of bleeding, hematoma, vasovagal response, in-stent thrombosis resulting in complete occlusion of the iliac vein stent, an allergic reaction, hematemesis, hypotension, pelvic discomfort, and pseudoaneurysm. ResultsBetween January 2015 and January 2019, 1223 iliac vein stents were placed in 1104 patients (23.7% male; 76.3% female). A total of 90 minor complications (7.36%) and 5 major complications (0.41%) were observed. The major complications included the following: one allergic reaction, one episode of atrial fibrillation, one episode of supraventricular tachycardia, one episode of chest pain, and one case of acute stent occlusion. The minor complications were primarily insertion site hematomas. No complications were related to sedation or acute renal failure. No patient died. ConclusionsMajor complications were rare after iliac vein stenting in an OBL setting. Minor complications were primarily insertion site hematomas, which did not require inpatient hospitalization. Our analysis has shown that iliac vein stenting in an OBL setting is a safe and well-tolerated procedure.

Outcomes and Risk Factors Associated with Thrombosis Recurrence and Post-Thrombotic Syndrome in Children and Adolescents with May-Thurner Syndrome

Introduction : May-Thurner syndrome (MTS) is a condition in which the right iliac artery compresses the left iliac vein, predisposing affected individuals to venous outflow obstruction and deep vein thrombosis (DVT). Despite the frequency of this anatomic variant, found in 20-25% of adults, not everyone with this variant will develop a DVT. Adults with MTS are treated with catheter-directed thrombolysis (CDT), anticoagulation, and often iliac vein stent placement. There is no standard of care established for pediatric MTS patients. The aims of this study are to 1) describe risk factors, clinical factors, and outcomes (complications of CDT, recurrence rate, post-thrombotic syndrome) in a pediatric MTS cohort and 2) determine what factors are associated with thrombus resolution, recurrence, and development of post-thrombotic syndrome (PTS).Methods : A retrospective cohort of children (0-21 years) diagnosed with MTS and DVT were identified between January 1, 2012 and July 15, 2017. MTS was confirmed by CT venogram, MR venogram, intravascular ultrasound, and/or conventional endovascular venography. Patient demographic, clinical, and thrombophilic risk factors, clinical outcomes (resolution, recurrence, PTS using modified Villalta scale), and bleeding complications were abstracted from review of the electronic medical record. Bleeding complications were defined by ISTH definitions for pediatric trials. Student's t test, Wilcoxon rank sum test, Chi square test and logistic regression analysis were used for statistical analysis (SAS v9.4, Cary, NC, USA).Results : The cohort was comprised of 23 subjects, 65% of them female (n=15), with a median age at presentation of 16.1 years (9.9-19.7 years). The median follow-up time was 505 days. The most frequent risk factor was thrombophilia (n=10), which included Factor V Leiden mutation (n=6), antithrombin deficiency (n=3), protein S deficiency (n=3), lupus anticoagulant (n=3), prothrombin gene mutation (n=1), protein C deficiency (n=1), or more than one thrombophilia (n=3). Other risk factors included hormone therapy (n=8), obesity (n=7), family history of DVT (n=6), immobility (n=5), central line (n=2), lupus (n=1), pregnancy (n=1), trauma (n=1), surgery (n=1), nephrotic syndrome (n=1), and retroperitoneal fibrosis (n=1). One subject had no risk factor, while 14 (61%) had multiple risk factors. Among the subjects, 78% underwent CDT (n=18) and 83% had stent placement (n=19). The remaining subjects will have future stent placement. Following CDT, there were no major bleeding complications (1 minor and 1 clinically relevant non-major bleeding complication). Other complications included pain (n=8), hemolysis (n=7), hemoglobinuria (n=2), hypofibrinogenemia requiring cryoprecipitate infusion (n=2), and transient increase in creatinine (n=1). Primary patency, defined as >90% patency of vessel diameter in the first week after CDT, was achieved in 91% (n=21). Thrombosis resolution was seen in 91% (n=21) of the cohort. Anticoagulant treatment prescribed included enoxaparin (65%), rivaroxaban (30%) and warfarin (26%). In univariate analyses, the only factor associated with thrombus resolution was primary patency (p=0.0012). DVT recurred in 13% (n=3), with a median time of 32 days off anticoagulation. The only factor associated with recurrence was antithrombin deficiency (p=0.048). Ten subjects (43%) had no evidence of PTS and 13 had mild PTS (57%). There were no significant factors associated with the development of PTS.Conclusions : To our knowledge, this is the largest retrospective cohort of pediatric subjects with MTS and DVT. Underlying thrombophilia was the most common risk factor found, suggesting that patients diagnosed with MTS warrant thrombophilia evaluation. Bleeding complications associated with CDT were minimal and non-bleeding complications were transient, demonstrating that CDT is safe in the pediatric population. Efficacy of CDT in this population is supported by the finding that primary patency is an important factor for thrombosis resolution. Lastly, thrombosis recurrence was not uncommon (13%) and was likely to occur soon after stopping anticoagulation. These findings demonstrate that multicenter studies are needed in children with MTS to evaluate the efficacy of CDT to achieve thrombus resolution, and that evaluation of thrombophilic risk factors should be considered. DisclosuresNo relevant conflicts of interest to declare.

Single-stage treatment with iliac vein stenting and stripping of the great saphenous vein for patients with left iliac vein compression syndrome

We sought to evaluate the safety and feasibility of single-stage treatment with left iliac vein stenting and saphenous stripping in patients with left iliac vein compression (LIVC) and left great saphenous vein (GSV) incompetence. s: We conducted a prospective cohort study of 72 patients diagnosed with LIVC and left GSV incompetence between June 2012 to Oct 2018. We evaluated the periprocedural, 30-day, and 1-year outcomes of venous clinical severity score (VCSS), Chronic Venous Insufficiency Questionnaire 2 (CIVIQ2), the success rate of stent placement, duration of intervention, length of hospital stay, duplex recurrence, and clinically visible recurrence. There were 43 patients in the two-staged group and 29 patients in the single-staged group. The clinical characteristics of the two groups were similar. There were no differences between the two groups in the technical success rate, perioperative mortality, and surgical morbidity. There was no significant difference in the duplex and clinically visible recurrence. The length of hospital stay was significantly lower in the single-staged group. The single-staged group was associated with a higher complication rate of ecchymosis. There was no death, pulmonary embolism, or contrast-induced nephropathy among the patients. The 1-year primary patency rate was similar. Both treatment approaches were equally effective and had a high technical success rate. The single-staged group had a higher complication rate of ecchymosis due to heparin applying during the procedure.

The effect of stent compression on in-stent restenosis and clinical outcomes in iliac vein compression syndrome.

To evaluate the effect of stent compression on in-stent restenosis (ISR) and clinical outcomes in patients with iliac vein compression syndrome (IVCS) after iliac vein stenting. Fifty patients with IVCS treated with iliac vein stenting (Smart Control, Cordis, USA) between March 2017 and October 2018 were consecutively enrolled in this study. Computed tomography venography (CTV) was performed to assess stent compression and ISR. Based on the degree of stent compression, patients were allocated to a significant stent compression (SSC) group and an insignificant stent compression (ISC) group. The incidence of ISR was analyzed between the SSC and ISC groups. Patients' venous clinical severity scores (VCSSs) and responses to the chronic venous insufficiency questionnaire (CIVIQ) one year after stenting were compared between the two groups to evaluate the clinical improvement of venous insufficiency. In total, 34% of patients had SSC. There were significant differences in the incidence of ISR (52.9% vs. 21.2%, P=0.023), and in each group, there was one case of stent occlusion (5.88% vs. 3.03%, P=0.999). Patients in the SSC group had a higher VCSS score (8.41±5.92 vs. 3.15±2.87, P=0.04) and a lower CIVIQ score (83.35±8.86 vs. 92.21±4.32, P=0.001). SSC has a significant effect on the incidence of ISR and the clinical outcomes of venous insufficiency. Thus, a dedicated iliac venous stent with sufficient radial resistive force, crush resistance, and outward radial force is needed to prevent the occurrence of stent compression.

Эндоваскулярные вмешательства у мужчин с синдромом хронической тазовой боли на фоне вторичной варикозной болезни вен малого таза

Objective to study the effectiveness of methods of endovascular treatment of May-Turner syndrome and nutcracker syndrome as a cause of varicose veins of the pelvis in men with chronic pelvic pain syndrome. Materials and methods a comprehensive examination was carried out in 445 men with chronic pelvic pain syndrome. The patients age ranged from 20 to 68 years (mean age 39.5 years). The diagnosis of varicose veins of the pelvis was established in 49 patients, of which 25 had primary varicose veins of the pelvis, in 24 - secondary varicose veins of the pelvis (13 patients with May-Turner syndrome, 11 patients with nutcracker syndrome). The patients with the nutcracker syndrome underwent embolization of the testicular and pelvic veins using the combined sandwich technique. Patients with May-Turner syndrome underwent stenting of the left common iliac vein. Results In order to assess the technical efficiency of endovascular treatment, control ultrasound was performed at 1, 3, 6 and 12 months. In 100% of cases, throughout the observation period, the patency of venous stents was maintained; in all cases of embolization of the left testicular vein, there was no blood flow in the embolized vein. In order to assess the clinical efficacy of endovascular treatment after 1, 3, 6, 9 and 12 months. after it, patients were questioned using the NIH-CPSI scale and VAS. The most significant changes in clinical manifestations and ultrasound data were observed after 3 months. after endovascular treatment. Conclusions Balloon angioplasty and iliac vein stenting in May-Turner syndrome and left gonadal vein embolization in nutcracker syndrome are minimally invasive treatments with a favorable patient safety profile.

Outcomes of endovenous laser ablation with additional iliac vein stenting of nonthrombotic lesions in patients presenting with active venous ulcers

ObjectiveWe evaluated the clinical outcomes of superficial and perforator ablation and the effects on wound healing by adding iliac vein stenting of nonthrombotic iliac vein lesions (NIVLs) in patients presenting with active venous ulcers. MethodsA retrospective analysis was performed of patients who had presented with venous ulcers and had a diagnosis of NIVLs from January 2017 to December 2019. Patients with a >50% diameter reduction in the iliac vein as determined by computed tomography venography had undergone transfemoral venography for further confirmation. Patients were divided into the endovenous laser ablation (EVLA) group and EVLA with stenting (EVLAS) group. The EVLA group had undergone endovascular laser treatment of superficial venous reflux, and the EVLAS group had undergone EVLA and stenting for NIVLs. The clinical outcomes were compared between the two groups. The primary end point was cumulative ulcer healing at 12 months. The secondary end points included complications, venous clinical severity score improvements, and pain scores during the follow-up period. Univariable and multivariable regression models were used to determine the refractory ulcer predictors. ResultsA total of 157 patients were included, 93 in the EVLAS group and 64 in the EVLA group. Of the 93 patients in the EVLAS group and patients in the EVLA group, 30 (32.26%) and 17 (26.56%) had presented with iliac venous occlusion, respectively (P = .48). The mean percentage of stenosis was 78.0% ± 13.6% in EVLAS group and 77.0% ± 14.0% in the EVLA group (P = .36). No significant differences in the general preoperative data were observed between the two groups. Cumulative ulcer healing at 1 year was 86.8% and 65.6% in the EVLAS and EVLA groups, respectively (P = .001). After a mean follow-up of 22 months (median, 24 months), the EVLAS group had a significantly improved venous clinical severity score compared with the EVLA group (EVLAS group, 8.3; EVLA group, 11.7; P = .01). Multivariable analysis of the entire cohort showed that obesity and employment that requires standing were predictive of refractory ulcers and that iliac venous stent placement was a protective factor for ulcer healing. ConclusionsThe results of the present study have suggested an association between improvement in the overall success of venous leg ulcer healing when including treatment of NIVLs with stents into a treatment plan that already includes saphenous and perforator vein ablation.

Abstract No. 504 Update: iliocaval-in-stent restenosis

To examine patient, stent, and angioplasty factors associated with 50% and 75% in-stent restenosis (ISR) of iliocaval stents placed for chronic venous thrombosis with results at 1, 3, 5, and 20 years post-placement. All patients with symptomatic chronic iliocaval venous thrombosis who underwent iliocaval stent placement with either SMART (Cordis, Santa Clara, CA) or Wallstent (Boston Scientific, Natick MA) at an academic medical center from 1996 to 2018 were compiled from a departmental database. In total, 620 iliocaval stents (430 SMART, 190 Wallstent) were placed in 176 patients (52.8% male, median age 51.1 y). Median follow -was 538.1 days (range, 0–6473 days). Rates of ISR at > 50% and > 75% luminal obstruction were calculated using Kaplan-Meier methods. Cox regression analysis of the effects of age, gender, stent brand, stent diameter, stent length, and angioplasty balloon diameter, on ISR was performed. Median and mean time to ISR were 153.5 and 299.2 days, respectively (range, 3–3985 days). In the 20 year follow-up period, ISR occurred in 8.7% of inferior vena cava (IVC) stents, 10.9% of common iliac vein (CIV) stents, and 15.3% of external iliac vein (EIV) stents. Gender did not affect ISR. Increased age was associated with a small but significant increased risk of ISR when all veins were examined as a single cohort at 1, 3, 5, and 20 years and within the EIV at 3, 5, and 20 years. Wallstents were associated with decreased rate of ISR when all veins were examined as a single cohort at 1, 3, 5, and 20 years as well as within EIV and CIV at 1, 3, 5, and 20 years. A small but significant increased risk of ISR was noted with larger stents in the EIV at 1, 3, 5, and 20 years and IVC at 1 year only as well as when all veins are examined as a single cohort at 1, 3, 5, and 20 years. Smaller balloon diameter demonstrated an increased risk of ISR within IVC stents at 1 year only. When the threshold for ISR was raised to > 75% ISR, all of the above significant results were the same. However, in addition, increasing stent length was associated with a small but significant risk of ISR > 75% when all veins were examined as a single cohort at 1, 3, 5, and 20 years. Our study demonstrates clinically acceptable and decreased rates of ISR compared to prior studies for the IVC, CIV, and EIV stents. Age is a small but significant risk factor for ISR, especially within the EIV. Wallstents may decrease ISR in iliac veins but are similar to SMART stents when placed in the IVC. Larger balloon diameters may help with short-term IVC ISR and larger stents may increase the risk of ISR in the EIV.

Pelvic venous insufficiency secondary to iliac vein stenosis and ovarian vein reflux treated with iliac vein stenting alone

BackgroundWe have previously reported that in women with a pelvic venous disorder secondary to pelvic venous insufficiency, 56% will present with an iliac vein stenosis (IVS) and ovarian vein reflux (OVR). The purpose of the present investigation was to determine whether women with combined disease can be treated using iliac vein stenting alone. MethodsA retrospective review of prospectively collected data at the Center for Vascular Medicine was performed. We investigated women with pelvic pain or dyspareunia secondary to combined IVS and OVR who had undergone stenting alone. The patient demographics, pre- and 6-month postoperative visual analog scale (VAS) for pain scores, stent type, stent diameter, stent length, and ovarian vein diameters were assessed. All patients had undergone diagnostic venography of their pelvic veins, left ovarian veins, and pelvic reservoirs and intravascular ultrasonography of their iliac veins. ResultsFrom May 2016 to October 2019, 82 patients with a pelvic venous disorder secondary to IVS and OVR were identified. The present data analysis focused on 38 patients with complete pre- and postoperative VAS scores and duplex scan stent patency data at 6 months. The pelvic and dyspareunia VAS scores at the initial and 6-month follow-up visits were as follows: 6.83 ± 3.19 and 4.24 ± 2.65 and 1.72 ± 2.01 and 0.05 ± 2.0, respectively (P ≤ .001). At 6 months, 29 of the 38 women (76%) reported complete resolution of all symptoms, 26 of 28 (93%) reported complete resolution of their dyspareunia, 5 of 38 (13%) reported significant improvement, and 4 of 38 (10%) reported no improvement. The average ovarian vein diameter was 6.7 ± 2.5 mm. The average stent size and length was 18.20 ± 1.6 mm and 92.41 ± 18.5 mm, with 25 placed in the left common iliac, 2 in the right common iliac vein, and 3 bilaterally. Of the 38 patients, 7 required reintervention (18%). An untreated pelvic reservoir was observed in 17 of the 38 patients (44%). One of the two with no response and six of the patients with improvement had OVR and an untreated pelvic reservoir. The remaining 10 patients with a pelvic reservoir had experienced complete resolution of their symptoms with stenting alone. ConclusionsOf the 38 women with pelvic pain secondary to combined IVS and OVR, 76% achieved complete symptom resolution with iliac vein stenting alone. Most of the women with a pelvic reservoir were asymptomatic and reported full symptom resolution after stenting alone. However, these data suggest that in some women, a relationship might exist between the presence of a pelvic reservoir and the persistence of symptoms. Therefore, for women with combined IVS and OVR, we recommend iliac vein stenting alone and staged ovarian vein embolization only for women with persistent symptoms.

Iliac Vein Stenosis: Is the Data Strong Enough for Stenting in the Young Pelvic Venous Disorders (PeVD) Population?

Iliac vein stenosis is a clinical condition resulting from external compression of the iliocaval venous unit with the consequent remodeling of the vascular wall, hemodynamic alterations, and predisposition to venous thrombosis. As such, the most common indications for percutaneous endovascular iliac vein stenting supported by the literature, include the management of thrombotic and non-thrombotic iliac venous lesions associated with advanced chronic venous disease (CVD). However, its clinical presentation is variable, and it may also include features associated with PeVD such as chronic pelvic pain, perineal heaviness, urinary urgency, postcoital pain, and vulvar or superficial non-saphenous veins varicosities. In this setting, the management revolves around the relieving venous obstruction and restoring normal blood flow through the compressed vein with percutaneous endovascular iliac vein stenting, that can be augmented with ovarian vein embolization (OVE) or direct embolization of the superficial varices. Given the heterogeneity of PeVD presentation and the lack of high-level quality data in outcomes for iliac vein stenosis stenting, this review will discuss the current evidence available for this intervention and clinical issues to consider when evaluating these patients.

Effect of Pre-Procedure Clopidogrel With Iliac Vein Stenting in Non-Thrombotic Vein Lesions.

Iliac vein stenting is a relatively new procedure in the treatment of chronic venous insufficiency. Research has shown that it is a safe and effective form of treatment, however, one of the well-known risks is in-stent thrombosis. We hypothesize that a single 75 mg dose of Clopidogrel the night prior to the procedures along with a 3-month regimen post-op would decrease the 30-day thrombosis rate. A retrospective study was performed on 3,518 patients from September 2012 to August 2018 who received an iliofemoral stent. Patients were broken down into 2 main groups: those given Clopidogrel post-stent and those given Clopidogrel both pre- and post-stent. In our practice, we prescribe a 3-month course of Clopidogrel after iliac vein stenting. Patients were also checked for any anticoagulant medications pre- and/or post-stent. The 30-day thrombosis rates were recorded for each patient. 1,205 patients received Clopidogrel pre-procedurally and post-procedurally, 1,941 patients received Clopidogrel only post-procedurally. 372 patients were excluded from the study because they were on other anti-coagulant medications. Mean follow-up for this cohort was 17 months. 112 total patients developed some degree of 30 day in-stent thrombosis (3.6%). 74 patients developed a complete thrombosis of the stent and 38 developed a partial (≤60% occlusion) thrombosis. Of the 1,205 patients who were on clopidogrel pre-stenting, 28 had a complete thrombosis and 10 had a partial in-stent thrombosis. Of the 1,941 patients on Clopidogrel only post-stenting, 46 had a complete thrombosis and 28 had a partial in-stent thrombosis. Using the Chi-squared test, there were no statistically significant differences between the group of patients receiving Clopidogrel pre- and post-stent vs. just post-stent with respect to 30-day any degree of thrombosis rates (complete and partial thrombosis) (p = .33). Using the Chi-squared test, there were no statistically significant differences between the group of patients receiving Clopidogrel pre- and post-stent vs. just post-stent with respect to 30-day complete thrombosis rates (p = .93). There appears to be no statistical difference in 30-day thrombosis rates between those receiving Clopidogrel the night prior vs. those who do not receive Clopidogrel the night prior. Therefore, we conclude that it is not necessary to give this single dose the night prior to iliac vein stenting procedures.

Pregnancy after Iliac Vein Stenting for Pelvic Venous Insufficiency

Pregnancy after Iliac Vein Stenting for Pelvic Venous Insufficiency

Common Iliac Vein Stenting for May-Thurner Syndrome and Subsequent Pregnancy: Patency and Outcomes

Common Iliac Vein Stenting for May-Thurner Syndrome and Subsequent Pregnancy: Patency and Outcomes

Doppler ultrasound and contrast-enhanced ultrasound in detection of stent stenosis after iliac vein stenting

BackgroundTo compare the diagnostic accuracy of Doppler ultrasound (DUS) with contrast-enhanced ultrasound (CEUS) for detection of iliac vein stent stenosis using multidetector computed tomography venography (MDCTV) as the reference method.MethodsPatients with iliac vein obstructive disease treated with nitinol stents (Smart Control, Cordis, USA) between January 2016 and December 2017 were consecutively included in this study. DUS, CEUS, and MDCTV were carried out in all patients within one week of each other at 1 year post stenting to investigate the presence of stent compression and in-stent restenosis (ISR).ResultsThe study included 139 patients (87 females; mean age 58 ± 15 years). For detecting stent compression, the kappa coefficient between the ultrasound modality of gray-scale imaging and MDCTV was 0.901, indicating very good agreement between these two modalities. ISR was detected in 50, 61, and 65 patients by DUS, CEUS, and MDCTV, respectively. DUS and CEUS (kappa = 0.449) and DUS and MDCTV (kappa = 0.516) had moderate agreement for ISR diagnosis, while for which CEUS and MDCTV (kappa 0.884) had very good agreement. The sensitivity and specificity of DUS and CEUS for diagnosing ISR were 63.1% and 90.8%, 87.8% and 97.3%, respectively.ConclusionsCEUS is probably superior to DUS in terms of diagnostic accuracy for the follow-up of patients with iliac vein stent stenosis.

Case of endovenectomy and stenting with functioning arteriovenous fistula in extended post-thrombotic occlusion of deep veins

We describe herein a case of surgical treatment of a 32-year-old female patient presenting with multilevel post-thrombotic occlusion of deep veins of the left lower limb. Laboratory study revealed high-risk hereditary thrombophilia (homozygous mutation of PAI-1, MTR, heterozygous mutation of MTHFR, MTRR, ITGA2). The first stage included endovenectomy from the common femoral vein with creation of an arteriovenous fistula between femoral vessels. An attempt of endovascular stenting of iliac veins was initially unsuccessful. After 3 months, the woman was rehospitalized to undergo successful endovascular operation with stenting of the iliac veins and common femoral artery on the background of the functioning arteriovenous fistula. The clinical outcome of the operation was good. Follow-up ultrasonographic examinations (ultrasound duplex scanning) were performed at 3, 6, 10 and 13 months after the second operation. The findings of ultrasound duplex scanning at 13 months showed that the stented segments of deep veins were freely patent, with the arteriovenous fistula functioning well. There were no signs of impairments of central haemodynamics, with significant regression of clinical symptoms. The total score by the Villalta scale as compared with the baseline values decreased from 13 to 5. Given the pattern of deep vein lesions, complexity of open and endovascular operations, and the presence of thrombophilia, we decided to abstain from disuniting the arteriovenous fistula. This case report demonstrates possibility, efficacy and safety of long functioning of an artificial arteriovenous fistula in a particular patient cohort.

An alternative explanation for the phasic variations in venous flow

BackgroundPhasic venous flow variation with respiration is surrounded by controversy and not well understood. The current concept assigns a major role to the “abdominal pump.” According to this model, inspiratory increases in abdominal pressure compress the vena cava, increasing its internal venous pressure and propelling blood upstream. Some have assigned a secondary role to the “thoracic pump,” with the negative intrapleural pressure aiding blood flow toward the heart. The aim of the present study was to examine the phasic changes in flow, pressure, and volume in the central veins and named tributaries. MethodsCaliber area changes were measured using intravascular ultrasonography in 37 patients undergoing iliac vein stenting. The pressure was measured in 48 patients using transducer tip catheters with electronic zero calibration. Duplex ultrasound flow in the head and neck and truncal and limb veins during inspiration and expiration was measured in 15 normal volunteers. ResultsThe caliber of the abdominal inferior vena cava had increased by 32% and its lateral pressure had decreased significantly during inspiration. Intravenous pressure in the central veins of the chest and right atrium was positive at 6 to 14 mm Hg. Negative pressures were rarely seen and then only transiently. The internal jugular vein displayed little phasic variation. The upper limb veins displayed weak inspiratory phasicity. Phase polarity was reversed in the lower limbs, with near flow stoppage during inspiration. ConclusionsThese observations conflict with the current notions of venous flow phasicity, which are based on push–pull pressure changes in the abdominal and thoracic veins. The paradoxical inspiratory inferior vena cava caliber increase probably explains the concurrent pressure decrease. Sustained negative pressures in the thoracic central veins and right atrium did not occur. We have proposed an alternate hypothesis for venous flow phasicity based on alternate stretching and relaxation of the mobile section of the great veins with respiratory movement.

Venous Recanalization and Stenting After Iliac Vein Injury

The objective of this study was to report an endovascular treatment for patients experiencing complications after iliac vein ligation. Management of venous injury consists largely of venous ligation or primary repair. Complications consist of lower extremity swelling, venous hypertension, venous thromboembolism, and compartment syndrome. Whereas conservative management is often successful for symptomatic swelling, there is little current literature regarding treatment of failed conservative therapy. A retrospective chart review performed from 2017 to 2020 identified three patients who underwent recanalization and venous stenting after previously ligated iliac vein. Case 1: A 23-year-old man suffered a gunshot wound to the left external iliac requiring ligation. He developed venous hypertension requiring fasciotomy of the left lower leg and thigh. Recanalization with stenting of the left external iliac vein with mechanical thrombectomy of the common femoral and external iliac vein was performed. Completion venography showed no residual stenosis. The patient was discharged on anticoagulation with normal flow on noninvasive studies 2 months later. Case 2: A 21-year-old man suffered a gunshot wound to the abdomen with injury to the inferior vena cava (IVC) and right iliac vein requiring ligation. Postoperatively, he developed iliac vein stenosis with symptomatic lower extremity swelling. Iliac vein recanalization with bilateral iliac vein stenting and IVC confluence reconstruction was performed. He was discharged on anticoagulation with patent venous stents and normal flow on noninvasive studies 2 months later. Case 3: A 44-year-old man presented with chronic swelling and left leg pain following ligation of the left iliac vein after iatrogenic injury during spinal surgery. Conservative compression therapy was unsuccessful. Preoperative computed tomography venography revealed chronic occlusion of the left iliac vein. Recanalization was performed, with improvement of flow through the left iliac system with filling into the IVC. The patient was discharged on anticoagulation, with patent stents on noninvasive studies at 6-month follow up. Venous recanalization with stenting is a successful treatment for complications after iliac vein ligation.

Iliac vein pathology and short-term stenting outcomes in a South-East Asian population: A single-centre experience.

Current literature regarding iliofemoral intervention and stenting is mostly based on Western populations. We present our experience of iliofemoral stenting for chronic venous disease within a South-East Asian population. This is a single-centre retrospective review of a prospectively collected registry. Seventy-one patients with 105 limbs underwent iliac vein IVUS and stenting between 2016 and 2019. All patients underwent pre-procedure ultrasound venous scan and MRI venogram. Pre- and post-operative CEAP classification, Villalta score and Venous Clinical Severity Score (VCSS), technical results, stent patency rates and complication rates are documented. Seventy-six per cent of the cases are non-thrombotic iliac vein lesion, and 68% of patients have C4 to C6 disease. Ten percentage of patients had acute thrombosis on presentation. There was 100% technical success. A 6- and 7-point reduction in the mean VCSS and Villalta score, respectively, were noted post-stenting (baseline of 10 points and P<0.001 in both categories). Post-stenting ulcer healing rate was 91% at 6 and 12months. One-year ulcer recurrence and cellulites recurrence were at 8% and 7%, respectively. One unplanned 30-day readmission (not related to procedure) and no 30-day mortality were noted. Bleeding complication from anticoagulation was 3%. There was 10% in-stent non-flow limiting stenosis on surveillance. One-year primary patency was 91%, and secondary patency was 100%. Within our series, iliofemoral stenting has 100% technical success, with statistically significant reduction in VCSS and Villalta score, good wound healing rates, low ulcer and cellulites recurrence and good primary and secondary patency rates at 1year.

Safety of vascular interventions performed in an office-based laboratory in patients with low/moderate procedural risk

ObjectiveAn exponential increase in number of office-based laboratories (OBLs) has occurred in the United States, since the Center for Medicare and Medicaid Services increased reimbursement for outpatient vascular interventions in 2008. This dramatic shift to office-based procedures directed to the objective to assess safety of vascular procedures in OBLs. MethodsA retrospective analysis was performed to include all procedures performed over a 4-year period at an accredited OBL. The procedures were categorized into groups for analysis; group I, venous procedures; group II, arterial; group III, arteriovenous; and group IV, inferior vena cava filter placement procedures. Local anesthesia, analgesics, and conscious sedation were used in all interventions, individualized to the patient and procedure performed. Arterial closures devices were used in all arterial interventions. Patient selection for procedure at OBL was highly selective to include only patients with low/moderate procedural risk. ResultsNearly 6201 procedures were performed in 2779 patients from 2011 to 2015. The mean age of the study population was 66.5 ± 13.31 years. There were 1852 females (67%) and 928 males (33%). In group I, 5783 venous procedures were performed (3491 vein ablation, 2292 iliac vein stenting); with group II, 238 arterial procedures (125 femoral/popliteal, 71 infrapopliteal, iliac 42); group III, 129 arteriovenous accesses; and group IV, 51 inferior vena cava filter placements. The majority of procedures belonged to American Society of Anesthesiology class II with venous (61%) and arterial (74%) disease. A total of 5% patients were deemed American Society of Anesthesiology class IV (all on hemodialysis). There was no OBL mortality, major bleed, acute limb ischemia, myocardial infarction, stroke, or hospital transfer within 72 hours. Minor complications occurred in 14 patients (0.5%). Thirty-day mortality, unrelated to the procedure, was noted in 9 patients (0.32%). No statistically significant differences were noted in outcomes between the four groups. ConclusionsOur data suggest that it is safe to use OBL for minimally invasive, noncomplex vascular interventions in patients with a low to moderate cardiovascular procedural risk.