Comparison of intravascular ultrasound and multidimensional contrast imaging modalities for characterization of chronic occlusive iliofemoral venous disease: A systematic review

Imaging of Deep Venous Pathology

Imaging plays an important role in the identification and assessment of clinically suspected venous pathology. The purpose of this article is to review the spectrum of image-based diagnostic tools used in the investigation of suspected deep vein disease, both obstructive (deep vein thrombosis and post-thrombotic vein changes) as well as insufficiency (e.g., compression syndromes and pelvic venous insufficiency). Additionally, specific imaging modalities are used for the treatment and during clinical follow-up. The use of duplex ultrasound, magnetic resonance venography, computed tomography venography and intravascular ultrasound as well as conventional venography will be discussed in this pictorial review.

A comprehensive study on venous endovascular management and stenting in deep veins occlusion and stenosis: A review study

Background

Patients with deep venous disease can be classified into two distinct categories: those with disease resulting from known deep vein thrombosis (DVT), which may subsequently lead to post-thrombotic syndrome (PTS), and those with disease caused by compressive factors or non-thrombotic iliac vein lesions (NIVL). The major factor causing the symptoms in patients with PTS and NIVL is venous hypertension which happens due to venous stenosis or venous obstruction. Nowadays Venous stenting offers a noninvasive approach for treatment of NIVL and PTS demonstrating high patency rate.

Methods

We comprehensively reviewed relevant published papers from 2008 to 2023 that surveyed various influencing factors including the site of occlusion and etiology of occlusions, proper diagnostic imaging, ideal characteristics of venous stents, different dedicated venous stents, pre-operative, concomitant, and post-operative interventions and factors that challenge stenting in both PTS and NIVL patients. The papers were identified by searching the keywords "venous stenting", "PTS", "NIVL", "occlusion", and "stenosis" in PubMed central library MEDLINE and Google Scholar.

Results

Patency rates, post-stent complications, and relevant data according to the patient's quality of life were included and analyzed from 476 identified studies. There is no validated protocol and guideline for using stents in patients with PTS and NIVL.

Conclusion

As there is no validated protocol and guideline for using stents in patients with PTS and NIVL, our study may provide comprehensive information to assist researchers interested in writing the protocol and give them insight.

Monitoring the venous circulation: novel techniques and applications

PURPOSE OF REVIEW

Venous pressure is an often-unrecognized cause of patient morbidity. However, bedside assessment of PV is challenging. We review the clinical significance of venous pressure measurement, existing techniques, and introduce the Venous Excess Ultrasound (VExUS) Score as a novel approach using doppler ultrasound to assess venous pressure.

RECENT FINDINGS

Studies show clear associations between elevated venous pressure and adverse outcomes in critically ill patients. Current venous pressure measurement techniques include physical examination, right heart catheterization (RHC), two-dimensional ultrasound, and a variety of labor-intensive research-focused physiological maneuvers. Each of these techniques have specific shortcomings, limiting their clinical utility. To address these gaps, Beaubien-Souligny et al. introduced the VExUS Score, a novel doppler ultrasound-based method that integrates IVC diameter with doppler measurements of the hepatic, portal, and renal veins to generate a venous congestion assesment. Studies show strong correlations between VExUS score and RHC measurements, and well as an association between VExUS score and improvement in cardiorenal acute kidney injury, diuretic response, and fluid status shifts. However, studies in noncardiac populations have been small, heterogenous, and inconclusive.

SUMMARY

Early studies evaluating the use of doppler ultrasound to assess venous congestion show promise, but further research is needed in diverse patient populations and clinical settings.

Lower extremity woven and nonwoven venous stent morphology and luminal changes

OBJECTIVE

Venous stents are a common treatment modality for obstructive venous disease. Venous stents differentiate themselves by either a woven or braided structure, open or closed cell arrangement or based on material composition (elgiloy vs nitinol). Changes in the morphology of venous stents over time may contribute to restenosis or thrombosis. Woven elgiloy stents are prone to proximal and distal edge deformation compared with dedicated venous stents, which offer increased radial force at stent edges. The objective of this study is to describe luminal morphological changes among various venous stents and between woven to nonwoven venous stent configuration, over time.

METHODS

A retrospective review at a single institution between January 2014 and June 2021 identified patients treated with venous stents. Patients with iliac and/or femoral venous stents with intraoperative intravascular ultrasound and a postoperative computed tomography scan were included in the study. Cross-sectional diameters measurements were taken at proximal, middle, and distal portions of each stent from intravascular ultrasound examination at the time of initial stenting and compared with the cross-sectional diameter measurements taken from computed tomography imaging at follow-up. A paired t test was used to compare the luminal change with a D'Agostino-Pearson test used for normality.

RESULTS

Fifty-four stents distributed among 38 patients were identified. The mean time to follow-up was 17.5 months. Stents were placed in the common iliac vein (n = 37, 68.5%), external iliac vein (n = 14, 25.9%), and common femoral vein (n = 3, 5.6%). Implanted stents included the Boston Scientific Wallstent (n = 23, 42.6%), Bard Venovo (n = 3, 5.6%), Boston Scientific Vici (n = 23, 42.6%), and Medtronic Abre (n = 5, 9.3%). The mean luminal loss was measured at 2.12 mm proximally (95% confidence interval [CI], 1.64-2.60; P<.001), 1.29 mm at the mid-stent (95% CI, 0.83-1.74, P<.001), and 1.56 mm distally (95% CI, 0.99-2.12; P<.001). There was no significant difference in luminal changes between woven and nonwoven stents at proximal (P = .374), middle (P = .179), and distal (P = .609) stent measurements.

CONCLUSIONS

This study reports morphological changes within venous stents and between woven and nonwoven venous stents. Our findings demonstrate that the edge-stent luminal decrease traditionally attributed to woven configurations also occurs with the newer nonwoven stents. Additional factors such as anatomical location, pelvic curvature, and other external forces may be accountable for this change rather than geometrical configuration of the stent.

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 FDA approval 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 manuscripts that are part of this series.

METHODS

This study conducted a literature search limited to English articles. Three search strategies were employed, and references were managed in Covidence software. Four investigators independently screened and evaluated articles, excluding meta-analyses, clinical trial protocols, and non-relevant studies. Eligible studies, focused on clinical outcomes and stent patencies, underwent thorough review.

RESULTS

The literature search yielded 1,704 studies, with 147 meeting eligibility criteria after screening and evaluation. Exclusions were based on duplicates, irrelevant content, and non-iliac vein stent placement.

CONCLUSION

Successful IVS for CIVO relies on meticulous patient selection, consistent use of IVUS during procedures, and attention to the technical details of IVS.

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.

Society of Interventional Radiology Position Statement on the Management of Chronic Iliofemoral Venous Obstruction with Endovascular Placement of Metallic Stents

PURPOSE

To state the position of the Society of Interventional Radiology (SIR) on the endovascular management of chronic iliofemoral venous obstruction with metallic stents.

MATERIALS AND METHODS

A multidisciplinary writing group with expertise in treating venous disease was convened by SIR. A comprehensive literature search was conducted to identify studies on the topic of interest. Recommendations were drafted and graded according to the updated SIR evidence grading system. A modified Delphi technique was used to achieve consensus agreement on the recommendation statements.

RESULTS

A total of 41 studies, including randomized trials, systematic reviews and meta-analyses, prospective single-arm studies, and retrospective studies were identified. The expert writing group developed 15 recommendations on the use of endovascular stent placement.

CONCLUSIONS

SIR considers the use of endovascular stent placement for chronic iliofemoral venous obstruction to be likely to help selected patients, but the risks and benefits have not been fully quantified in well-designed randomized studies. SIR recommends urgent completion of such studies. In the meantime, careful patient selection and optimization of conservative therapy are recommended prior to stent placement, with attention to appropriate stent sizing and quality procedural technique. The use of multiplanar venography with intravascular ultrasound is suggested in diagnosing and characterizing obstructive iliac vein lesions and in guiding stent therapy. After stent placement, SIR recommends close patient follow-up to ensure optimal antithrombotic therapy, durable symptom response, and early identification of adverse events.

Association between the degree of iliac venous outflow obstruction by intravascular ultrasound and lower limb venous reflux

OBJECTIVE

The present study aims to evaluate the association between the degree of iliac venous outflow obstruction (IVOO) identified by intravascular ultrasound (IVUS) and venous reflux presentation in the lower limbs on duplex ultrasound (DU).

METHODS

Patients with bilateral chronic venous insufficiency, CEAP (clinical-etiology-anatomy-pathophysiology) C3 to C6, and a visual analog scale score for pain >5 underwent DU for reflux evaluation of the deep venous system (reflux ≥1 second); superficial system, great saphenous vein, and small saphenous vein (reflux ≥0.5 second); and perforator system (reflux ≥0.35 second). All patients underwent IVUS in the iliac venous territory. The area of the impaired venous segments was categorized as obstruction <50% (category 1), 50% to 79% (category 2), and ≥80% (category 3). The venous clinical severity score and reflux multisegment score (RMS) were assessed.

RESULTS

A total of 51 patients (n = 102 limbs; age, 50.53 ± 14.5 years; 6 men) were included. The predominant clinical severity CEAP class was C3 in 54 of 102 limbs (52.9%). The mean VCSS was 14.3 ± 6.7. A severe RMS (≥3) was registered in 63.4% of the limbs. Of the 102 limbs, 51 (50%) presented with category 1, 27 (26.5%) with category 2, and 24 (23.5%) with category 3. Previous deep vein thrombosis (DVT) was associated with critical obstruction (odds ratio [OR], 3.65; 95% confidence interval [CI], 1.29-10.38; P = .015). The superficial and perforator venous systems had no association with the degree of IVOO. Deep venous reflux (DVR) had a significant association with significant IVOO (obstruction ≥50%; OR, 6.44; 95% CI, 2.19-18.93; P = .001) and critical IVOO (obstruction ≥80%; OR, 4.57; 95% CI, 1.70-12.27; P = .003) and a significant linear association with the IVOO degree and reflux in the femoral veins (P < .001) and popliteal vein (P = .008). Significant lesions were significantly more likely to develop in the left limb (OR, 5.76; 95% CI, 2.46-13.50; P < .001). After multivariate analysis, DVR remained a predictor for significant and critical obstruction (P < .003 and P < .012, respectively). Left limb and previous DVT remained as predictors for IVOO of ≥50% and ≥80% (P < .001 and P = .043, respectively).

CONCLUSIONS

We found a significant linear association between the degree of IVOO and reflux in the deep venous system on DU. Limbs with DVR, a severe RMS, loss of respiratory variation on DU, and previous DVT were more likely to be affected by IVOO of ≥50%, especially with left leg involvement.

Delphi Consensus on Reporting Standards in Clinical Studies for Endovascular Treatment of Acute Iliofemoral Venous Thrombosis and Chronic Iliofemoral Venous Obstruction

Acute iliofemoral deep vein thrombosis and chronic iliofemoral venous obstruction cause substantial patient harm and are increasingly managed with endovascular venous interventions, including percutaneous mechanical thrombectomy and stent placement. However, studies of these treatment elements have not been designed and reported with sufficient rigor to support confident conclusions about their clinical utility. In this project, the Trustworthy consensus-based statement approach was utilized to develop, via a structured process, consensus-based statements to guide future investigators of venous interventions. Thirty statements were drafted to encompass major topics relevant to venous study description and design, safety outcome assessment, efficacy outcome assessment, and topics specific to evaluating percutaneous venous thrombectomy and stent placement. Using modified Delphi techniques for consensus achievement, a panel of physician experts in vascular disease voted on the statements and succeeded in reaching the predefined threshold of >80% consensus (agreement or strong agreement) on all 30 statements. It is hoped that the guidance from these statements will improve standardization, objectivity, and patient-centered relevance in the reporting of clinical outcomes of endovascular interventions for acute iliofemoral deep venous thrombosis and chronic iliofemoral venous obstruction in clinical studies and thereby enhance venous patient care.

Clinical tolerance of untreated reflux after iliac vein stent placement

BACKGROUND

We have recently demonstrated in a large patient cohort that the prevalence and severity of reflux will improve in most limbs after stenting and that most limbs will not develop new-onset reflux. In the present report, we have focused on the long-term clinical outcomes associated with untreated reflux in the same patient cohort who had undergone iliofemoral venous stenting without correction of residual reflux.

METHODS

The clinical outcomes data from 1379 limbs treated with only iliac vein stenting without correction of superficial or deep reflux from 1997 to 2018 were analyzed (23-year follow-up period). Of the 1379 limbs, 632 (46%) had had preexisting reflux before stenting and 747 (54%) had did not. The reflux data (reflux segmental score, air plethysmography, ambulatory venous pressure) for these patients have been previously reported in detail. The subsets were compared perioperatively with each other using the following variables: grade of swelling, visual analog scale for pain score, venous clinical severity score, venous stasis dermatitis, ulceration, and quality of life measures.

RESULTS

Both groups demonstrated improvements in the venous clinical severity score, grade of swelling, visual analog scale score, and quality of life. No differences were found in ulcer healing (5% vs 3% for limbs with and without prestent reflux, respectively) and resolution of dermatitis (6% vs 5% for limbs with and without prestent reflux, respectively) between the two groups. Of the 632 limbs with preexisting reflux, 218 (34%) had had axial reflux and 414 had had nonaxial reflux (66%). The clinical outcomes were similar between the two groups. Using a multisegment reflux score, the limbs with prestent reflux (n = 632) were divided into two groups. A segmental score of ≥3 indicated severe reflux and a score of <3 indicated moderate reflux. Of these 632 limbs, 161 (25%) had severe reflux and 471 (75%) had moderate reflux. The two groups demonstrated similar outcomes for most clinical parameters. The post-thrombotic limbs and nonthrombotic limbs also showed similar outcomes.

CONCLUSIONS

The long-term follow-up of patients after iliac vein stenting showed that uncorrected reflux is well tolerated by most patients across most clinical measures.

An Overview of Specific Considerations in Chronic Venous Disease and Iliofemoral Venous Stenting

Unlike arterial disease, chronic venous disease (CVD) is rarely life-threatening or limb-threatening. However, it can impose substantial morbidity on patients by influencing their lifestyle and quality of life (QoL). The aim of this nonsystematic narrative review is to provide an overview of the most recent information on the management of CVD and specifically, iliofemoral venous stenting in the context of personalized considerations for specific patient populations. The philosophy of treating CVD and phases of endovenous iliac stenting are also described in this review. Additionally, the use of intravascular ultrasound is described as the preferred operative diagnostic procedural tool for iliofemoral venous stent placement.

Society of Interventional Radiology Position Statement on the Endovascular Management of Acute Iliofemoral Deep Vein Thrombosis

PURPOSE

To establish the updated position of the Society of Interventional Radiology (SIR) on the endovascular management of acute iliofemoral deep vein thrombosis (DVT).

MATERIALS AND METHODS

A multidisciplinary writing group with expertise in treating venous diseases was convened by SIR. A comprehensive literature search was conducted to identify studies on the topic of interest. Recommendations were drafted and graded according to the updated SIR evidence grading system. A modified Delphi technique was used to achieve consensus agreement on the recommendation statements.

RESULTS

A total of 84 studies, including randomized trials, systematic reviews and meta-analyses, prospective single-arm studies, and retrospective studies were identified and included in the review. The expert writing group developed 17 recommendations that pertain to the care of patients with acute iliofemoral DVT with the use of endovascular venous interventions.

CONCLUSIONS

SIR considers endovascular thrombus removal to be an acceptable treatment option in selected patients with acute iliofemoral DVT. Careful individualized risk assessment, high-quality general DVT care, and close monitoring during and after procedures should be provided.

Iliac vein stent failure in community practice and results of corrective reinterventions

OBJECTIVE

The goal of endovenous stenting is to relieve venous obstruction and reduce peripheral venous hypertension by using large caliber venous stents in the presence of adequate venous inflow and outflow for the stented conduit. The aim of this report is to describe the technical reasons and outcomes for reinterventions in a subset of patients who had a history of iliac vein stenting and were now referred to us at a specialty venous clinic for further care.

METHODS

From January 2016 to December 2021, records of all patients who were referred to us with a history of iliac vein stenting performed at an outside facility and who had a reoperation performed at our center were retrospectively analyzed.

RESULTS

A total of 149 limbs underwent a deep venous reintervention after a failure of a trial of conservative therapy. The mean age of the sample was 57 ± 16 years. The ratio of non-thrombotic iliac vein lesions to post-thrombotic lesions was 1:2.5. The majority of the patients (84%) were CEAP class C4 or higher. The most common reason for reintervention was stent occlusion (74%), followed by iatrogenic stenosis (53%) and in-stent restenosis/shelving (38%). There was a trend for improvement in all clinical parameters (venous clinical severity score, visual analog scale for pain, and edema grade) after the reintervention. Poor inflow was present in 70% of limbs with stent occlusion. The median diameters of stented common femoral vein, external iliac vein, and common iliac vein prior to reintervention were 12, 12, and 13 mm, respectively. The median diameters of stented common femoral vein, external iliac vein, and common iliac vein after reintervention were 14, 15, and 16 mm, respectively. Eighty-eight percent of limbs required at least one further reintervention after initial reoperation.

CONCLUSIONS

Venous reoperations are generally infrequent and required in a small number of patients. Poor inflow appeared to be a common cause of stent occlusion. Iatrogenic stenosis is another common reason for venous reoperation and is difficult to fully rectify through current endovascular techniques and tools. Use of intravascular ultrasound planimetry routinely in every deep venous intervention and thorough knowledge of the principles of venous stenting outlined in this report may help forestall the need for reoperative deep venous surgery in some cases.

Intravascular ultrasound evaluation during iliofemoral venous stenting is associated with improved midterm patency outcomes

OBJECTIVE

Intravascular ultrasound (IVUS) examination is increasingly used in the treatment of iliofemoral venous disease and provides more sensitive and specific detection of stenotic lesions when compared with traditional multiplanar venography alone. Correlations with deep venous stent patency, however, have not yet been investigated. The objective of the study was to evaluate the impact of the use of IVUS examination in addition to multiplanar venography on iliofemoral venous patency.

METHODS

Consecutive patients who underwent stenting for symptomatic thrombotic or nonthrombotic iliofemoral venous lesions (NIVLs) between 2014 and 2020 at a single institution were identified and divided into two groups based on whether IVUS examination was used before stent deployment in addition to multiplanar venography compared with venography alone. A retrospective review of demographic, operative, and follow-up data was performed. Thirty-day and 2-year stent patency were measured as primary end points. χ² analysis, logistic regression models, and Kaplan-Meier survival analysis were used to determine outcomes. Technical details and outcomes were additionally examined among patients treated for acute deep venous thrombosis, post-thrombotic syndrome, or NIVLs separately on subgroup analysis.

RESULTS

We identified 150 patients (173 limbs, 23 bilateral) who underwent iliofemoral stenting during the study period at our institution (mean age: 48.8 ± 16.8 years, 61% female). Adjunctive IVUS utilization before stent deployment was reported in 69 of 173 (39.9%) treated limbs. IVUS examination was more likely to be used in patients who underwent stenting for NIVLs compared with thrombotic disease (41.0% vs 11.2%, P < .01). There was no difference in the number of stents deployed between IVUS and non-IVUS cohorts. However, IVUS examination was associated with the increased total length of the stent deployed (126 ± 56 vs 112 ± 48 mm, P = .04) and a higher rate of infrainguinal stent extension (17.4% vs 6.7%, P = .03). In addition, mean stent diameter was significantly higher when IVUS examination was performed before stent placement (16.3 ± 3.7 vs 15.2 ± 1.9 mm, P < .01). Both 30-day (98.5% vs 89.4%, P = .02) and 2-year (90.3% vs 78.7%, P = .03) primary patency were significantly higher in the IVUS cohort. Adjunctive IVUS use was found to significantly protect against stent reintervention at 2 years on adjusted Cox regression analysis (hazard ratio: 0.22, 95% confidence interval: 0.07-0.71, P = .01).

CONCLUSIONS

Adjunctive IVUS utilization is associated with differences in stent diameter and length selections as well as landing segments in the treatment of thrombotic and nonthrombotic iliofemoral venous disease. IVUS examination before stent deployment significantly protects against 30-day and 2-year stent reintervention when compared with the use of multiplanar venography alone. These data provide stronger evidence for routine IVUS use in addition to venography before iliofemoral venous stenting.

Options in the treatment of superficial and deep venous disease in patients with Klippel-Trenaunay syndrome

OBJECTIVE

Klippel-Trenaunay syndrome (KTS) is a congenital mixed mesenchymal malformation syndrome that includes varicose veins, capillary and venous malformations, lymphatic abnormalities, and hypertrophy of various connective tissue elements. The purpose of the present study was to describe the clinical characteristics and outcomes in a subset of patients with KTS in whom venous interventions, including iliofemoral venous stenting, were performed after failure of conservative therapy.

METHODS

A single-center retrospective data review of 34 patients with KTS who had undergone interventions for venous disease between January 2000 and December 2020 was performed.

RESULTS

Their mean age was 38.4 ± 17.5 years (range, 12-80 years). No gender predilection was found. Of the 34 patients, 61% had had all three features of the classic triad for KTS. Varicose veins were present in all 34 patients (100%), and 30% had had a history of bleeding varicosities. Most patients (79%) had CEAP (Clinical, Etiology, Anatomy, and Pathophysiology) class ≥C4. Of the 34 patients, 30% had a history of deep vein thrombosis and/or pulmonary embolism. Factor VIII elevation was the most common thrombophilia condition (12%). The venous filling index was elevated at baseline (5.9 ± 5.1 mL/s) and did not normalize despite intervention (3.5 ± 2.3 mL/s; P = .04). The superficial venous interventions (n = 35) included endovenous laser therapy; stripping of the great saphenous vein, small saphenous vein, anterior thigh vein, or marginal vein; ultrasound-guided sclerotherapy; and stab avulsion of varicose veins. One coil embolization of a perforator vein was performed. Deep interventions (n = 19) included endovenous stenting (n = 15), popliteal vein release (n = 3), and valvuloplasty (n = 1). The venous clinical severity score had improved from 9.4 ± 4.5 to 6.2 ± 5.6 (P = .04). The visual analog scale for pain score had improved from 5.5 ± 2.7 to 2.5 ± 3.3 (P = .008). Healing of ulceration was noted in 75% of the patients. Significant improvements in the total pain (P = .04) and total psychological (P = .03) domains were noted in the 20-item chronic venous disease quality of life questionnaire.

CONCLUSIONS

Superficial and deep venous interventions are safe and effective in patients with KTS when conservative therapy has failed. Iliofemoral venous stenting is a newer option that should be considered in the treatment of chronic deep venous obstructive disease in patients with KTS in the appropriate clinical context. An aggressive perioperative deep vein thrombosis prophylaxis protocol should be in place to reduce thromboembolic complications in these patients.

Percutaneous laser recanalization in chronically occluded iliofemoral venous stents

Occlusion is a challenging complication of endovenous stenting. The treatment of chronic iliofemoral stent occlusion involves wire recanalization followed by balloon angioplasty. However, this approach will not always be successful. To treat such cases, we have successfully used a laser recanalization technique in 34 limbs (31 patients). This technique involved the use of a laser to first create a channel through the chronically occluded stent, followed by balloon angioplasty to improve the caliber of this recanalized tract. The mean age of the patients was 52 ± 13.6 years (range, 24-73 years). No adverse events related to the use of the laser occurred. Following laser recanalization, the venous clinical severity score had improved from 8.2 ± 4 to 5.1 ± 3.3 (P < .0001). The visual analog scale score for pain had improved from 7.8 ± 2.5 to 4.9 ± 3 (P = .0009). The grade of swelling had improved from 2.7 ± 1.3 to 1.6 ± 1.4 (P = .0001). At 12 months after intervention, the primary stent patency was 60% (standard error of the mean, 9.3%), and the secondary stent patency was 80%. Excimer laser recanalization of chronically occluded venous stents appears to be a rarely required but useful modality with reasonable clinical outcomes. Further reinterventions might be required to maintain long-term stent patency.

Utility of a percutaneous mechanical thrombectomy device in retrieval of an iatrogenic intravascular foreign body

Intravascular foreign bodies can result from endovascular procedures and from other medical implants and devices. A wide variety of techniques and devices have been described for the retrieval of such intravascular foreign bodies in reported studies. In the present report, we have described the case of a patient with a symptomatic left innominate vein deep vein thrombosis who also had a retained catheter fragment from a fractured tunneled infusion catheter in the left innominate vein. Using the Inari ClotTriever system (Inari Medical, Irvine, CA), we were able to, not only restore venous outflow by treating the acute deep vein thrombosis, but also retrieve the fragments of the fractured catheter.

Appropriate Use of Intravascular Ultrasound During Arterial and Venous Lower Extremity Interventions

BACKGROUND

There has been growing use of intravascular ultrasound (IVUS) during lower extremity arterial and venous revascularization. Observational data suggest that the use of IVUS can improve periprocedural and long-term outcomes, but largescale prospective data remain limited. Consensus opinion regarding the appropriate use of IVUS during peripheral intervention is needed.

OBJECTIVES

The purpose of this consensus document is to provide guidance on the appropriate use of IVUS in various phases of peripheral arterial and venous interventions.

METHODS

A 12-member writing committee was convened to derive consensus regarding the appropriate clinical scenarios for use of peripheral IVUS. The group iteratively created a 72-question survey representing 12 lower extremity arterial interventional scenarios. Separately, a 40-question survey representing 8 iliofemoral venous interventional scenarios was constructed. Clinical scenarios were categorized by interventional phases: preintervention, intraprocedure, and postintervention optimization. Thirty international vascular experts (15 for each survey) anonymously completed the survey instrument. Results were categorized by appropriateness using the median value and disseminated to the voting panel to reevaluate for any disagreement.

RESULTS

Consensus opinion concluded that IVUS use may be appropriate during the preintervention phase for evaluating the etiology of vessel occlusion and plaque morphology in the iliac and femoropopliteal arteries. IVUS was otherwise rated as appropriate during iliac and femoropopliteal revascularization in most other preintervention scenarios, as well as intraprocedural and postprocedural optimization phases. IVUS was rated appropriate in all interventional phases for the tibial arteries. For iliofemoral venous interventions, IVUS was rated as appropriate in all interventional phases.

CONCLUSIONS

Expert consensus can help define clinical procedural scenarios in which peripheral IVUS may have value during lower extremity arterial and venous intervention while additional prospective data are collected.

Comparison of intravascular ultrasound and magnetic resonance venography in the diagnosis of chronic iliac venous disease

BACKGROUND

The diagnosis of chronic iliofemoral venous obstruction (CIVO) can be made with several different modalities. Intravascular ultrasound (IVUS) is the gold standard in the diagnosis of CIVO. However, being invasive, it should not be the initial examination to screen patients with CIVO. The aim of this report is to compare the performance of magnetic resonance venography (MRV) to IVUS in the diagnosis of CIVO.

METHODS

From January, 2016 to December, 2020, records of all patients who underwent pre-operative MRV and then IVUS in the evaluation of CIVO were retrospectively analyzed.

RESULTS

505 patients were evaluated by any modality for CIVO. 15% (78) of these patients were evaluated by MRV. Patients who had failed a trial of conservative therapy for at least 3 - 6 months and who had disabling and life-style limiting symptoms of CIVO were selected to undergo further evaluation with MRV at the treating physician's discretion. For inclusion in analysis, technically satisfactory IVUS and MRV data was mandatory. Data was available for 60 common iliac vein (CIV) segments and 61 external iliac vein (EIV) segments for comparative analysis after appropriate exclusions. The mean age of the patients was 56 ± 15 years. Male to female ratio was 1:2. The distribution of patients across different CEAP classes was as follows: CEAP 3: 28%, CEAP 4: 62%, CEAP 5: 2% and CEAP 6: 8%. Bland-Altman plots of mean difference in area between IVUS and MRI were 74.1% for CIV and 56.9% for EIV. The sensitivity of MRV was 93% and 100% while the specificity was 0 and 50% for CIV and EIV respectively. The positive predictive value was 93% and 86% while the negative predictive value was 0 and 50% for CIV and EIV respectively. Improvement was noted in clinical parameters (Venous Clinical Severity score; VCSS, visual analogue pain scale and grade of swelling) after IVUS and stenting following MRV investigation. For VCSS, the score improved from 6 ± 2.7 (pre-procedure) to 4 ± 2.7 (post-procedure), p=0.0001.

CONCLUSION

There is dimensional disparity between MRV and IVUS in the diagnosis of symptomatic CIVO. MRV has a high sensitivity but low specificity when compared to IVUS and overestimates the severity of the stenosis in both the EIV and CIV. MRV is not a reliable diagnostic tool for iliac vein stenosis and should not be used for the definitive disposition of CIVO patients.

The Application of MEVEC 3D Doppler Ultrasound Technique for a New Classification of Morpho-Functional Phenotypes in Lower Limbs Venous Diseases

Introduction

MEVEC 2.1 is a novel 3D mapping software dedicated to the evaluation of the venous vascular three of the lower limbs. It has already proven as a sensitive, specific, and accurate technique able to provide better morphologic and functional details of the lower limb venous system than standard reports. The aim of this study was to identify specific morpho-functional graphic phenotypes in lower limb venous diseases by means of MEVEC 2.1.

Materials

Three-hundred eleven consecutive outpatients underwent lower limb Doppler ultrasound examination by means of the MEVEC 2.1 technique. All of them showed at least one among these pathological findings: venous insufficiency, thrombosis, incompressibility, and/or incompetent.

Results

We tried to evaluate possible clusters among the different morpho-functional findings from the venous maps in order to outline reproducible phenotypes. Correlation indexes allowed us to provide a classification in morpho-functional phenotypes in order to standardize the data from examinations performed by different physicians. Twelve phenotypes had been proposed.

Conclusion

The study showed that the MEVEC 2.1 technique provides a standardized classification that allows physicians identifying phenotypes yielded by 3D mapping of the veins of the lower limbs.

Management of iatrogenic inferior vena cava perforation with composite Wallstent-Z-stent technique

Inferior vena cava rupture is uncommon but can occur as a result of trauma or catheterization and during venous interventions. We have described two cases of iatrogenic inferior vena cava perforation, with their successful management with bare metal stents (a composite Wallstent–Z-stent technique). This management strategy was possible owing to the unique properties of the venous system.

Iliofemoral venous stenting in patients with central neuromuscular disorders

BACKGROUND

Leg swelling in patients with various central neuromuscular disorders is a common clinical scenario and can lead to significant morbidity. The aim of the present study was to evaluate a subset of patients with central neuromuscular disorders who had undergone iliofemoral venous stenting at a specialty venous clinic at a tertiary care hospital.

METHODS

From January 2000 to December 2020, the medical records of all patients with a known central neuromuscular disorder who had undergone iliofemoral venous stenting for chronic iliofemoral venous obstruction were retrospectively analyzed.

RESULTS

A total of 42 patients (45 limbs) with central neuromuscular disorders had undergone iliofemoral stenting after failure of a trial of conservative therapy. The central neuromuscular disorders included Parkinson disease (n = 20 limbs), multiple sclerosis (n = 15 limbs), and other neuromuscular conditions (n = 10 limbs). The mean age of the sample was 59 ± 14 years. The ratio of post-thrombotic to nonthrombotic iliac vein lesions was 3:1. Most of the patients had had CEAP (clinical, etiologic, anatomic, pathophysiologic) class ≥C4 (64.4%); 25 limbs had a history of venous thromboembolism (56%). A trend was seen toward improvement in all clinical parameters measured (venous clinical severity score, visual analog scale for pain score, and edema grade) after stenting. An ulcer healing rate of ≤90% was noted after stenting. Of the 45 limbs, 24 had required some form of reintervention (53%) after initial stent placement.

CONCLUSIONS

Venous intervention in the form of endovenous stenting was associated with improvement in the clinical parameters for patients with central neuromuscular disorders. However, these patients should be counseled regarding the relatively higher rate of reinterventions that might be required to correct residual or recurrent symptoms.