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.

Fibulin-1 promotes intimal hyperplasia after venous stent implantation through ACE mediated angiotensin II signaling

Objective

Stent intimal hyperplasia leads to in stent restenosis and thrombosis. This study determined whether Fibulin-1 activity in smooth muscle cells (SMCs) contributes to stent restenosis or thrombosis.

Methods

Stent implantation was conducted in a pig model. Target vessel samples were stained and analyzed by protein mass spectrometry. Cell experiments and Fibulin-1 SMC specific knockout mice (Fbln1SMKO) were used to investigate the mechanism of Fibulin-1 induced SMC proliferation and thrombosis.

Results

SMC proliferation and phenotypic transition are the main pathological changes of intimal hyperplasia in venous stents. Protein mass spectrometry analysis revealed a total of 67 upregulated proteins and 39 downregulated proteins in intimal hyperplasia after stent implantation compared with normal iliac vein tissues. Among them, Fibulin-1 ranked among the top proteins altered. Fibulin-1 overexpressing human SMCs (Fibulin-1-hSMCs) showed increased migration and phenotypic switching from contractile to secretory type and Fibulin-1 inhibition decreased the activity of SMCs. Mechanistically, Fibulin-1-hSMCs displayed increased levels of angiotensin converting enzyme (ACE) expression and angiotensin II signaling. Inhibition of ACE or angiotensin II signaling alleviated the migration of Fibulin-1-hSMCs. Using Fibulin-1 SMC specific knockout mice (Fbln1SMKO) and venous thrombosis model, we demonstrated that Fibulin-1 deletion attenuated intimal SMCs proliferation and thrombosis. Further, Fibulin-1 concentration was high in iliac vein compression syndrome (IVCS) patients treated with stent and was an independent predictor of venous insufficiency.

Conclusions

Fibulin-1 promotes SMC proliferation partially through ACE secretion and angiotensin II signaling after stent implantation. Fibulin-1 plays a role in venous insufficiency syndrome, implicating the protein in the detection and treatment of IVCS.

Quantitative Flow Measurements of Pelvic Venous Vasculature Using 4D Flow MRI

RATIONALE AND OBJECTIVES

To evaluate 4D Flow magnetic resonance imaging (MRI) sequences for quantitative flow measurements of the pelvic venous vasculature.

MATERIALS AND METHODS

A prospective study of healthy volunteers was performed. After informed consent all subjects underwent 4D flow sequences at a 3 T MRI scanner with different isotropic resolution and different velocity encoding (Venc) settings: (sequence #1) voxel size (VS) 1.63 mm3, Venc 50 cm/s; (sequence #2) VS 1.63 mm3, Venc 100 cm/s and (sequence #3) VS 2.03 mm3, Venc 50 cm/s. Perfusion parameters were calculated for all venous vessel segments starting at the level of the inferior vena cava and extending caudally to the level of the common femoral vein. For reference, arterial flow was calculated using 1.63 mm3 isotropic resolution with a Venc of 100 cm/s.

RESULTS

Ten healthy subjects (median age 28 years, interquartile range [IQR]: 26.25-28 years) were enrolled in this study. Median scanning time was 12:12 minutes (IQR 10:22-13:32 minutes) for sequence #1, 11:02 minutes (IQR 9:57-11:19 minutes) for sequence #2 and 6:10 minutes (IQR 5:44-6:47 minutes) for sequence #3. Flow measurements were derived from all sequences. The venous pelvic vasculature showed similar perfusion parameters compared to its arterial counterpart, for example the right common iliac arterial segment showed a perfusion of 8.32 ml/s (IQR: 6.94-10.68 ml/s) versus 7.29 ml/s (IQR: 4.70-8.90 ml/s) in the corresponding venous segment (P = 0.218). The venous flow measurements obtained from the three investigated sequences did not reveal significant differences.

CONCLUSION

4D Flow MRI is suitable for quantitative flow measurement of the venous pelvic vasculature. To reduce the scanning time without compromising quantitative results, the resolution can be decreased while increasing the Venc. This technique may be utilized in the future for the diagnosis and treatment response assessment of iliac vein compression syndromes.

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

Background

In its normal anatomical relationship, the inferior vena cava is located on the right side of the abdominal aorta. Iliac vein compression syndrome (IVCS) is a pathological condition in which a blood clot is formed due to blood flow obstruction when the left common iliac vein is compressed between the right common iliac artery and the vertebral body. Therefore, right-sided IVCS (RIVCS) is rare. The effectiveness of treatment for RIVCS has not been sufficiently investigated.

Case summary

A 51-year-old man developed deep vein thrombosis in the right lower extremity and non-massive pulmonary embolism during steroid treatment for IgA nephropathy. Magnetic resonance angiography (MRA) suggested iliac compression syndrome. Symptoms improved with the use of direct oral anticoagulants and compression stockings. At the 8-month follow-up, the clinical course was uneventful.

Discussion

The causes of RIVCS in this case are believed to be the effects of steroids, prolonged sitting, and compression of the right external iliac vein. However, considering that deep vein thrombosis did not form in the left lower limb where there was no venous compression, it can be considered that the compression of the right external iliac vein had a significant impact. This case has been followed up for 8 months with anticoagulants and is progressing well. This is the first case to report the course of RIVCS treated conservatively with anticoagulant therapy for 8 months. This case suggested that conservative treatment is effective for RIVCS.

Efficacy of modified time of flight magnetic resonance venography in diagnosis of iliac vein compression syndrome

OBJECTIVE

We investigated the diagnostic efficacy of modified time of flight magnetic resonance venography (mTOF-MRV) for iliac vein compression syndrome diagnosis by optimizing the scanning parameters and improving image quality.

METHODS

A retrospective study was conducted on 69 patients who underwent routine time of flight magnetic resonance venography (TOF-MRV) and 85 patients who received mTOF-MRV. Assessment of image quality of the two methods was performed by two radiologists using a four-point method. The sensitivity, specificity, positive and negative predictive values of TOF-MRV and mTOF-MRV in the diagnosis of significant iliac vein compression (stenosis >50%) were analyzed by calculating the iliac vein stenosis rates of the two methods and using digital subtraction angiography (DSA) as the gold standard.

RESULTS

Inter-observer assessment of objective data measurement revealed excellent agreement {ICC [95% confidence interval (CI)]: 0.972 (0.953 to 0.983) for TOF-MRV and 0.979 (0.965 to 0.988) for m-TOF MRV, 0.976 (0.960 to 0.986) for DSA}. The mean error of stenosis rate of mTOF-MRV was markedly smaller than that of TOF-MRV (p < 0.05). Sensitivity, specificity, positive and negative predictive values of TOF-MRV in the diagnosis of significant stenosis were 100%, 95%, 67% and 100%, respectively. The sensitivity, specificity, positive and negative predictive values of mTOF-MRV were 100%. The mean image score for the mTOF-MRV was 3.63 ± 0.59, which was significantly higher compared with that of TOF-MRV (2.19 ± 0.42).

CONCLUSION

mTOF-MRV has better image quality and can accurately diagnose venous stenosis. Therefore, it can be used for the detection of iliac vein compression syndrome and further assessment after endovascular interventions.

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.

An ultrasound imaging and computational fluid dynamics protocol to assess hemodynamics in iliac vein compression syndrome

OBJECTIVE

Elevated shear rates are known to play a role in arterial thrombosis; however, shear rates have not been thoroughly investigated in patients with iliac vein compression syndrome (IVCS) owing to imaging limitations and assumptions on the low shear nature of venous flows. This study was undertaken to develop a standardized protocol that quantifies IVCS shear rates and can aid in the diagnosis and treatment of patients with moderate yet symptomatic compression.

METHODS

Study patients with and without IVCS had their iliac vein hemodynamics measured via duplex ultrasound (US) at two of the following three vessel locations: infrarenal inferior vena cava (IVC), right common iliac vein, and left common iliac vein, in addition to acquiring data at the right and left external iliac veins. US velocity spectra were multiplied by a weighted cross-sectional area calculated from US and computed tomography (CT) data to create flow waveforms. Flow waveforms were then scaled to enforce conservation of flow across the IVC and common iliac veins. A three-dimensional (3D), patient-specific model of the iliac vein anatomy was constructed from CT and US examination. Flow waveforms and the 3D model were used as a basis to run a computational fluid dynamics (CFD) simulation. Owing to collateral vessel flow and discrepancies between CT and US area measurements, flows in internal iliac veins and cross-sectional areas of the common iliac veins were calibrated iteratively against target common iliac flow. Simulation results on mean velocity were validated against US data at measurement locations. Simulation results were postprocessed to derive spatial and temporal values of quantities such as velocity and shear rate.

RESULTS

Using our modeling protocol, we were able to build CFD models of the iliac veins that matched common iliac flow splits within 2% and measured US velocities within 10%. Proof-of-concept analyses (1 subject, 1 control) have revealed that patients with IVCS may experience elevated shear rates in the compressed left common iliac vein, more typical of the arterial rather than the venous circulation. These results encourage us to extend this protocol to a larger group of patients with IVCS and controls.

CONCLUSIONS

We developed a protocol that obtains hemodynamic measurements of the IVC and iliac veins from US, creates patient-specific 3D reconstructions of the venous anatomy using CT and US examinations, and computes shear rates using calibrated CFD methods. Proof-of-concept results have indicated that patients with IVCS may experience elevated shear rates in the compressed left common iliac vein. Larger cohorts are needed to assess the relationship between venous compression and shear rates in patients with IVCS as compared with controls with noncompressed iliac veins. Further studies using this protocol may also give promising insights into whether or not to treat patients with moderate, yet symptomatic compression.

Iliac vein compression syndrome caused by a large bladder diverticulum: Case report and literature review

Iliac vein compression syndrome is a rare disorder that causes oedema of one or both legs, with or without thrombosis. This current case report describes a 71-year-old male patient with left iliac vein compression caused by a bladder diverticulum that occurred secondary to chronic prostatic hyperplasia. The patient presented with left leg oedema without deep vein thrombosis. Contrast-enhanced computed tomography of the abdomen and pelvis, Doppler ultrasound imaging of the lower limb veins and magnetic resonance imaging helped confirm the diagnosis. The patient initially underwent urinary catheter placement, which relieved urinary retention and iliac vein compression. He subsequently underwent bladder diverticulectomy and transurethral prostatectomy. The postoperative clinical course was uneventful. During the 1.5-year follow-up, the patient did not have lower extremity oedema. Bladder diverticulum is an extremely rare cause of iliac vein compression syndrome, and only five such cases, including this one, have been reported to date. This article presents a literature review of these cases and a summary of the diagnosis and treatment experience.

Clinical outcomes of different endovenous procedures among patients with varicose veins and iliac vein compression: A retrospective cohort study

OBJECTIVE

This study aimed to investigate the short-term outcomes of three endovenous procedures in patients with varicose veins (VVs) and severe iliac vein compression syndrome (IVCS).

METHODS

A total of 158 consecutive patients were included in this multicenter retrospective study from May 2017 to December 2019; 54 patients underwent endovenous laser ablation (EVLA) alone, 47 patients underwent EVLA and balloon angioplasty (BA), and 57 patients underwent EVLA and stenting angioplasty (SA). Clinical outcomes and complications were assessed at one and twelve months post-surgery. The Quality of life (QoL) was assessed by the venous clinical severity score (VCSS) and Aberdeen Varicose Vein Questionnaire (AVVQ).

RESULTS

Patients who underwent the SA procedure were older (P < 0.05). Incidence of laser ablation complications was similar among the three procedures; closure rates of the great saphenous vein were 96.8%, 98.0%, and 98.4%, respectively, at 12 months. Reflux times in the SA procedure were lower than those in the EVLA and BA procedures at 12 months, while ulcer healing time was faster with the SA procedure (P < 0.05) than with the other procedures. The VCSS and AVVQ values were significantly improved post-procedure (P < 0.05), with lower AVVQ scores in the SA procedure than in the EVLA and BA procedures at 12 months post-surgery. The EVLA and BA procedures (stenosis >70%) caused a significantly higher symptom recurrence than the SA procedure, with an odds ratios of 14.04 (95% confidence interval (CI), 1.99-99.18) and 10.50 (95% CI, 1.26-87.15), respectively.

CONCLUSIONS

Our results demonstrate that EVLA and SA procedures relieve symptoms, improve the QoL, and decrease symptom recurrence in patients with VVs and severe IVCS (stenosis >70%).

Prevalence of hypercoagulable states in stented thrombotic iliac vein compression syndrome with comparison of re-intervention and anticoagulation regimens

BACKGROUND

Endovascular therapy is playing an increasing role in the treatment of iliofemoral venous disease. Iliac stent patency is multifactorial, and current management is based on best clinical practices, varying by institution.

AIM

To evaluate how thrombophilia influences management and outcomes of patients who undergo venous stenting for thrombotic iliac vein compression syndromes.

METHODS

A retrospective observational analysis was performed on 65 patients with thrombotic iliac vein compression syndrome that underwent common iliac vein (CIV) stenting between December 2013 and December 2019 at a large academic center. Search criteria included CIV stenting and iliac vein compression. Non-thrombotic lesions and iliocaval thrombosis and/or occlusions were excluded. A total of 65 patients were selected for final analysis. Demographic information, procedural data points, and post-procedural management and outcomes were collected. Statistical analyses included Fisher's exact and Chi-square tests to compare discrete variables and the Wilcoxon rank-sum test to compare continuous variables between thrombophilia positive and negative patients.

RESULTS

65 patients underwent successful balloon angioplasty and CIV stenting. Of these patients, 33 (50.8%) underwent thrombophilia testing, with 16 (48.5%) testing positive. Stent patency on ultrasound did not significantly differ between thrombophilia positive and negative patients at 1 mo (92.3% vs 81.3%, P = 0.6), 6 mo (83.3% vs 80%, P > 0.9), or 12 mo (77.8% vs 76.9%, P = 0.8). Immediately after stent placement, thrombophilia patients were more likely to be placed on dual therapy (aspirin and anticoagulation) or triple therapy (aspirin, clopidogrel, and anticoagulation) (50% vs 41.2%, P > 0.9), and remain on dual therapy at 6 mo (25% vs 12.5%, P = 0.5) and 12 mo (25% vs 6.7%, P = 0.6). There was no significant difference in re-intervention rates (25% vs 35.3%, P = 0.7) or number of re-interventions (average 2.3 vs 1.3 per patient, P = 0.4) between thrombophilia positive and negative patients.

CONCLUSION

Half of patients with stented thrombotic iliac vein compression syndrome and thrombophilia testing were positive. The presence of thrombophilia did not significantly impact stent patency or re-intervention rates.

Novel typing of iliac vein compression in asymptomatic individuals evaluated by contrast enhanced CT

Purpose

Compression of the iliac vein between the iliac artery and lumbosacral vertebra can cause iliac vein compression syndrome (IVCS). The purpose of this study is to assess compression characteristics and establish a new sub-typing in asymptomatic IVCS individuals using contrast-enhanced CT.

Methods

A retrospective analysis of abdomen contrast-enhanced CT images from 195 asymptomatic subjects with iliac vein compressed was investigated. Patients had no history of venous pathology, and images were collected from June 2018 to January 2019. Qualitative and quantitative characteristics of compression were examined including the location, pattern, minor diameter, area, and the percentage compression on an orthogonal section by the post-processing of multiple planar reconstruction and volume rendering.

Results

There were 107 females and 88 males with age range 18–92 years. The most common site of iliac vein compression was localized to the left common iliac vein (LCIV) (178/195, 91.3%). Notably, four compression types (type I–IV) were established according to the compression location, with type II being the most common. The four compression types had differences in the upper limit and fluctuation range of compression. It was found that the average level of iliac vein compression was below 25%. The compression degree of the left common iliac vein in type II was relatively concentrated, and the upper limit of compression was close to 70%.

Conclusion

Asymptomatic iliac vein compression was categorized according to compression location. The proposal of four types might help clinicians to predict which IVCS patients would benefit from interventional therapy.

Percutaneous endovenous intervention without vena cava filter for acute proximal deep vein thrombosis secondary to iliac vein compression syndrome: preliminary outcomes

The aim is to report the preliminary outcomes of percutaneous endovenous intervention (PEVI) for acute proximal deep vein thrombosis (DVT) secondary to iliac vein compression syndrome (IVCS) without inferior vena cava filter (IVCF) placement. Acute DVT patients who underwent PEVI without IVCF were analyzed retrospectively. PEVI consisted of catheter-directed thrombolysis, manual aspiration thrombectomy, balloon angioplasty and stenting. CT was used to evaluate the left common iliac vein (LCIV). Sixty-two consecutive patients (17 men and 45 women, mean age, 59.4 ± 15.2 years) were enrolled. The compression percentage of the LCIV ranged from 51.7% to 95.2% (median 83.2%). Iliac DVT was present in 7 patients; iliofemoral, in 30 patients; and iliofemoropopliteal, in 25 patients. Complete technical success and clinical improvement were obtained in all subjects without the occurrence of symptomatic pulmonary embolism (PE). Five patients experienced recurrent thrombosis. The primary patency rates at 12 and 24 months were 93.8% and 91.4%, respectively, which remained stable at 36, 48 and 60 months. The secondary patency rates at 12 and 24 months were 95.7% and 93.3%, respectively, and there was no change at 60 months. Although limited, our preliminary results suggested that PEVI without IVCF placement seemed to be safe and effective for acute proximal DVT secondary to IVCS without inferior vena cava thrombosis or symptomatic PE.

Clinical outcomes of radiofrequency ablation for patients with varicose veins of the lower extremities combined with grade II iliac vein compression

BACKGROUND

Iliac vein compression (IVC) is a common condition in patients with varicose veins (VVs) of the legs. IVC has been classified into three grades in previous studies. Grade II IVC is defined by >50% stenosis without the development of collateral circulation. The purpose of the present study was to investigate the outcomes of radiofrequency ablation (RFA) for patients with VVs combined with grade II IVC.

METHODS

A retrospective analysis was conducted of 339 patients who had undergone RFA for VVs of the left leg from March 2017 to January 2019. Duplex ultrasonography, computed tomography venography, and venography were performed to evaluate for grade II IVC. All the patients were divided into two groups. Group 1 included patients with VVs only, and group 2, patients with VVs combined with grade II IVC. Propensity score matching was used to ensure an even distribution of confounding factors between groups. The venous clinical severity score (VCSS) and chronic venous insufficiency questionnaire (CIVIQ) score were recorded during the 12-month follow-up. Occlusion of the truncal veins was evaluated using duplex ultrasound scans.

RESULTS

Using 1:1 propensity score matching, 50 pairs of patients were enrolled in the present analysis. The average age of groups 1 and 2 was 58.7 ± 13.1 and 60.1 ± 7.1 years, respectively. The VCSS had decreased significantly from baseline to 12 months postoperatively (group 1, from 5 to 1; group 2, from 4 to 1; P < .01). A significant increase in the CIVIQ score was found between the baseline and 12-month evaluations for both groups (group 1, from 62.5 to 69; group 2, from 63 to 70; P < .01). The truncal occlusion rate was 98% in both groups at 12 months. No significant differences were found between the two groups in the VCSS, CIVIQ score, procedure complications, or occlusion rate during the 12-month follow-up.

CONCLUSIONS

RFA is effective for patients with VVs combined with grade II IVC.

Association between deep vein thrombosis and stent patency in symptomatic iliac vein compression syndrome: Systematic review and meta-analysis

BACKGROUND

The study intended to evaluate stent primary patency rates for patients with iliac vein obstruction related with iliac vein compression syndrome according to clinic presentation.

METHODS

A systematic review and meta-analysis was conducted of studies that compared: unexposed patients with nonthrombotic iliac vein lesion (NIVL, group 1) vs exposed patients with iliac acute deep vein thrombosis (DVT, group 2); and NIVL (group 1) vs exposed patients with iliac vein obstruction and post-thrombotic syndrome (PTS, group 3). The following databases were searched: EMBASE, PubMed, Web of Science, Scopus, SciELO, and LILACS. Two reviewers independently selected the potential studies and extracted data. The pooled odds ratio (OR) and 95% confidence interval (95% CI) are shown for each outcome.

RESULTS

Five studies with a total of 1050 participants and 1169 lower limbs were included. Five hundred eighty-eight lower limbs presented NIVL (50.3%), 91 lower limbs presented acute DVT (7.7%), and 490 lower limbs presented PTS (42%). The endovascular technical success rate of stenting did not differ in any of the groups: 99.6% in NIVL, 94.5% in acute DVT, and 96.5% in PTS (P = .0632). The primary stent patency rates in the 6-month follow-up were 98.3% in NIVL vs 90.9% in PTS, with a statistical difference showing reduced stent patency rates in PTS (OR, 0.17; 95% CI, 0.06-0.48; P = .0008; I² = 0%), and 100% in the NIVL group vs 91.6% in acute DVT, with no statistical difference (OR, 0.30; 95% CI, 0.06-2.32; P = .30; I² = 0%). The primary stent patency rates in the 12-month follow-up were 94.6% in NIVL vs 84.1% in PTS, with a statistical difference showing decreases stent patency rates in the PTS group (OR, 0.29; 95% CI, 0.14-0.63; P = .0008; I² = 0%), and 91.1% in NIVL vs 90.9% in acute DVT, with no statistical difference (OR, 1.03; 95% CI, 0.26-4.07; P = .96; I² = 0%).

CONCLUSIONS

There is no statistical difference for the stent primary patency rates when the treatment is conducted in NIVL as compared with acute DVT lower limbs (at 6 and 12 months); therefore, other criteria must be considered for the indication of this treatment in NIVL patients. However, because there were better results of stent primary patency rates for NIVL vs PTS patients, this finding favors the treatment of acute DVT instead of PTS in lower limbs, once PTS renders smaller stent patency rates at 6 and 12 months.

Iliac vein stenting is a safe and effective treatment for iliac vein compression syndrome: A systematic review of Chinese data

OBJECTIVES

This study was a systematic review of available data from China, and our aim was to evaluate the safety and efficacy of stenting in iliac vein compression syndrome.

METHODS

We searched the PubMed, National Knowledge Infrastructure, Chongqing Weipu Information Company, and Cochrane Central Register for Controlled Trials databases, and key references.

RESULTS

Twelve studies were included (nine retrospective analyses, two retrospective case series studies, and one prospective cohort study) involving 2292 patients and 1897 stented limbs. The overall primary patency rates ranged from 81.8% to 100%. Studies showed significant improvements in patients' symptoms, and ulcer healing rates ranged from 71.4% to 100% in stented limbs. The incidence of severe complications ranged from 0 to 16.8%.

CONCLUSIONS

For Chinese patients with iliac vein compression syndrome, stenting provided significant efficacy regarding favorable patency rates, symptom relief, and complications. However, the quality of evidence to support the use of iliac vein stenting to treat iliac vein compression syndrome is currently weak, especially for Chinese patients.

Intervention for Iliofemoral Deep Vein Thrombosis and May-Thurner Syndrome

May-Thurner syndrome, also known as iliac vein compression syndrome, may cause symptoms of venous hypertension and is a predisposing factor for the development of iliofemoral deep vein thrombosis (DVT). Iliofemoral DVT is associated with high rates of development of postthrombotic syndrome, a potentially debilitating condition associated with development of symptoms related to venous outflow obstruction and resulting in reduced quality of life. In this Clinics article, we review procedural intervention with catheter-directed thrombolysis and stenting for iliofemoral DVT and iliac vein compression.

[Endovascular treatment for non-thrombotic right iliac vein compression syndrome with intravascular ultrasound]

Objective: To evaluate the clinical efficacy of endovascular treatment for non-thrombotic right iliac vein compression syndrome with intravascular ultrasound. Methods: The clinical data of 40 patients with non-thrombotic right iliac vein compression syndromereceiving intravascular ultrasound-assisted balloon dilatation combined with stent implantation from January 2012 to December 2018 were retrospectively analyzed. There were 32 males and 8 females, the average age of whom was 63 (46-81) years old. The patients were classified according to the CEAP (Clinical-Etiology- Anatomy-Pathophysiology) classification: 7 cases as C3, 18 as C4, 10 as C5 and 5 as C6. All patients underwent percutaneous right femoral vein puncture, intravascular ultrasound, and balloon dilatation combined with stentimplantation in the right iliac vein lesion location. Results: The success rate of clinical operations was 100%. There were no serious complications during the perioperative period. All patients were followed up for 4-58 months. During the follow-up period, the relief rate of limb edema was 88.6% (31/35), the pain relief rate was 86.7%(13/15), and the healing rate of ulcers was 100% (6/6). After the stent implantation, the endovascular area of the compression site was significantly enlarged (34.5mm(2)± 11.1mm(2)vs129.8 mm(2)±17.2 mm(2), P<0.001). The follow-up of color Doppler and/or anterograde angiography for deep veins of lower limb with digital subtraction angiography showed that the blood flow in the stentsweres mooth in all patients. Three cases were observed that the intimal hyperplasia led to mild in-stent restenosis, no obvious in stent restenosis (>50%). The abdominal X-ray plain film showed no obvious displacement and fracture of the stents. The venous clinical severity score (VCSS) was statistically significant (13.0±2.4 vs 6.2±2.0, P<0.001). The statistical results of short-form health surver SF-36 showed that the scores of life quality in all dimensions of the affected limb were significantly improved after operation (P=0.000). Conclusion: Intravascular ultrasound-assisted balloon dilatation combined with stent implantation is not only a safe and effective treatment for non-thrombotic right iliac vein compression syndrome, but also has a good mid-term patency rate.

The clinical outcome of a one-stop procedure for patients with iliac vein compression combined with varicose veins

BACKGROUND

Primary iliac vein compression syndrome (IVCS) often is manifested with varicose veins (VVs), but the treatment of patients with IVCS combined with VVs remains unclear. The aim of this study was to investigate the outcome of a one-stop procedure for patients with IVCS and VVs.

METHODS

The 32 enrolled patients underwent iliac stenting first and then endovenous laser ablation for VVs. The reflux time of the femoral vein, peak reflux velocity, and mean flow velocity were measured, and the effect on quality of life was also assessed using the Aberdeen Varicose Vein Questionnaire and Venous Clinical Severity Score. All clinical data have been recorded and analyzed.

RESULTS

The success rate of the procedures was 100%. No serious complications occurred. The Aberdeen Varicose Vein Questionnaire score and Venous Clinical Severity Score of patients were significantly lower at 1 month, 6 months, and 12 months after the procedure compared with scores before the procedure (P < .01). The reflux time and peak reflux velocity were lower at 6 and 12 months after the procedure (P < .01), and the mean flow velocity was higher at 6 and 12 months after the procedure (P < .05). The patency rate of the iliac vein stent was 100% during follow-up, and one patient (3.13%) had a restenosis without symptoms.

CONCLUSIONS

The one-stop procedure for patients with IVCS combined with VVs is a safe and effective method that might be a therapy choice for these patients.

Strategies for the diagnosis and treatment of the iliac vein compression syndrome

Aim

To evaluate the diagnosis and treatment strategies for the iliac vein compression syndrome (IVCS) and the factors that affect the treatment outcome.

Methods

In total, 69 patients with IVCS were enrolled in the study. The patients underwent computed tomography (CT) venography before treatment. CT observations included assessment of the iliac venous channel sagittal diameter (IVCD) before the lower lumbar vertebra, causes of oppression, thrombus density, and embolization range. The patients with IVCS were divided into the simple IVCS (sIVCS, n = 22), lumbar degeneration-related type IVCS (dIVCS, n = 33), and IVCS of other causes (oIVCS, n = 14) including lumbar fracture, hematoma of infection, and abscess wraping around and compressing the iliac vein, groups. The treatment methods included target venous catheter-directed thrombolysis (CDT), a mechanical breaking and sucking treatment for the thrombi, followed by balloon dilatation and iliac vein stent implantation. The factors that may possibly affect the treatment outcomes included IVCS type, duration of disease, thrombus hardness, embolization length, and treatment regimen. Logistic regression was used to analyze the factors that affected the therapeutic efficacy.

Results

At the first stage, CDT was only effective in 15 cases (5 dIVCSs and 10 oIVCSs) and was ineffective in the remaining 54 cases, which required further mechanical breaking and sucking of the thrombi and intravenous balloon dilatation. In the second stage, combination of thrombi breaking and suction and balloon dilatation was preliminarily effective in 26 cases (6 sIVCSs, 16 dIVCSs and 4 oIVCSs), but during follow-up from 1 to 6 months, treatment was considered futile for 9 recurrent cases (3 sIVCSs and 6 dIVCSs). So, 28 cases of preliminary ineffective treatment and 9 relapse in the second stage were arranged to the third stage of treatment by iliac vein stent implantation. All 37 cases were treated effectively and achieved a satisfactory iliac vein patency, and were followed-up for 24 months without recurrence. Logistic regression analysis showed that IVCS type (β = 4.14; Wald test, P < 0.01), duration of illness (β = -5.33; Wald test, P = 0.02), thrombus density (β = -6.46; Wald test, P = 0.01), embolization length (β = 2.74; Wald test, P = 0.03), and treatment regimens (β = 11.92; Wald test, P = 0.01) all had a significant effect on the treatment outcomes.

Conclusion

The selection of a suitable intervention treatment regimen for different types of IVCS may aid in improving the curative effect.

Reciprocal enhancement of thrombosis by endothelial-to-mesenchymal transition induced by iliac vein compression

AIMS

Endothelial-to-mesenchymal transition (EndMT) is a pathophysiological change of vascular endothelium commonly seen in the cardiovascular system. Iliac vein compression syndrome (IVCS) is known to be often associated with intimal hyperplasia and thrombosis. However, whether EndMT exists in IVCS has not yet been reported. The purpose of this study was to investigate the relationship between EndMT and thrombosis in IVCS.

MAIN METHODS

Using IVCS models in pig and mouse, we detected intimal changes and thrombus in stenotic iliac vein by immunofluorescence staining. Primary human umbilical vein endothelial cells (HUVEC) were stimulated by transforming growth factor β1 (TGF-β1) and thrombin, and cell phenotypic transition and antithrombotic function of HUVEC were examined through q-PCR, western blot and ELISA. In the end, by immunofluorescence staining, we observed the effect of anticoagulant on interstitial changes of venous endothelial cells in IVCS models.

KEY FINDINGS

We showed that iliac vein compression induced EndMT, of which its inhibition reduced thrombus formation. Further studies showed that HUVECs undergoing EndMT lost their anticoagulation and thrombolytic function. Interestingly, thrombin aggravated EndMT through TGF-β/Smad3 signaling. Moreover, compared with wild type (WT) mice, EndMT in stenotic iliac vein was reduced in WT mice fed with rivaroxaban or factor VII knockout mice, implying that anticoagulation alleviated EndMT in IVCS models.

SIGNIFICANCE

Our findings indicate that EndMT and thrombosis reinforce reciprocally in IVCS, implying that targeting EndMT could be a potential strategy in prevention and treatment of thrombosis in IVCS.

Sciatic Neuralgia Caused by May-Thurner Syndrome

BACKGROUND

Sciatic neuralgia (SN) is a type of pain commonly associated with lumbosacral radiculopathy. May-Thurner syndrome (MTS) is a disease characterized by venous congestion in the left common iliac vein (LCIV) due to right common iliac artery compression. A case of MTS with SN as the first presenting symptom is described.

CASE DESCRIPTION

A 53-year-old man gradually developed left SN; however, radiologic examination showed no causal findings. Conservative medical treatment did not result in satisfactory pain relief. During the follow-up period, edema and brownish skin pigmentation were noted on the left crural region. Follow-up magnetic resonance imaging of lumbar spine revealed vascular enlargement around the spine and compression of the LCIV by the right common iliac artery. Furthermore, the left S1 nerve root was compressed by enlarged veins, which was thought to be the cause of the left S1 radiculopathy and SN. After the stenosed part of the LCIV was expanded, the pain and edema in the left leg disappeared.

CONCLUSIONS

This is the first report of SN associated with MTS. MTS should be considered as one of the differential diagnoses of SN. Thus, symptoms such as pain, edema, and skin hyperpigmentation on the left leg should be closely noted.

Editor's Choice - Reconstruction of the femoro-ilio-caval outflow by percutaneous and hybrid interventions in symptomatic deep venous obstruction

OBJECTIVE/BACKGROUND

Deep venous obstruction is relatively prevalent in patients with chronic venous disease. Endovascular treatments and hybrid interventions can be used to relieve venous outflow obstructions. This paper assesses mid-term clinical outcomes and patency rates in a large cohort after percutaneous and hybrid interventions.

METHODS

This was a prospectively analysed cohort study. Patients with symptomatic deep venous obstruction who presented at a tertiary referral hospital were divided into three groups: patients who underwent percutaneous stenting for non-thrombotic iliac vein compression syndrome (IVCS group); patients with post-thrombotic syndrome (PTS) treated by percutaneous stent placement (P-PTS group); and PTS patients with obstruction involving the veins below the saphenofemoral junction in which a hybrid procedure was performed, combining stenting with open surgical disobliteration (H-PTS group). Patency rates, complications, and clinical outcomes were analysed.

RESULTS

A total of 425 lower extremities in 369 patients were treated. At 60 months, primary patency, assisted primary patency, and secondary patency rates were 90%, 100%, and 100% for IVCS, and 64%, 81%, and 89% for the P-PTS group, respectively. The H-PTS group, showed patency rates of 37%, 62%, and 72%, respectively, at 36 months. Venous claudication subsided in 90%, 82%, and 83%, respectively. At the 24 month follow-up, mean Venous Clinical Severity Score decreased for all patients and improvement in Villalta score was seen in post-thrombotic patients. The number of complications was related to the extent of deep venous obstruction in which patients in the H-PTS group showed the highest complication rates (81%) and re-interventions (59%).

CONCLUSION

Percutaneous stent placement to treat non-thrombotic iliac vein lesions, and post-thrombotic ilio-femoral obstructions are safe, effective, and showed patency rates comparable with previous research. Patients with advanced disease needing a hybrid procedure showed a lower patency rate and more complications. However, when successful, the clinical outcome was favourable at mid-term follow-up and the procedure may be offered to selected patients.

May-Thurner syndrome: an often overlooked cause for refractory venous leg ulcers

We report a 53-year-old female patient presenting with a refractory venous leg ulcer and unremarkable findings in the doppler Ultrasound venous mapping of the leg veins. Further comprehensive diagnostics demonstrated an underlying May-Thurner syndrome. After resolution of the primary mechanical obstruction, rapid wound healing in the following 3 weeks was documented. Iliac vein compression syndrome, commonly known as May-Thurner syndrome, is a distinguishable anatomical variant that results from an external compression over the left iliac vein exerted by the overriding adjacent right common iliac artery. It is mostly seen among young, healthy female patients and can easily be under-diagnosed. Lower extremities duplex ultrasonography remains the gold standard in diagnosing venous insufficiency, but it should not solely depend on it. Instead, clinicians should consider other possibilities, assessing the patency within the truncal veins, which in turn might contribute to the venous insufficiency along the lower limbs. An active early diagnostic approach can prevent significant overall morbidity and help patients to ease back into their daily-life activities. Therefore, it is recommended that all patients with suspected venous insufficiency and normal lower limbs duplex findings should undergo further evaluation of the truncal venous system pattern. May-Thurner syndrome, along with other causes of iliac veins compression, should be considered in the differential diagnosis in unclear persistent cases of unilateral venous symptoms.

Successful treatment of deep vein thrombosis caused by iliac vein compression syndrome with a single-dose direct oral anti-coagulant

Background

Although vein stenting is popular for treatment for venous thromboembolism due to mechanical compression, some cases are forced to avoid inserting align agents because of immunodeficiency.

Case presentation

An 82-year-old man with left extremity redness and swelling presented to a hospital for a medical evaluation. The patient was immunodeficient because of the adverse effects of his treatment for Castleman’s disease. A contrast-enhanced computed tomography scan revealed a venous thromboembolism in inferior vena cava and the left lower extremity. Magnetic resonance venography showed that the iliac artery was compressing the iliac vein. We were reluctant to place a stent in the iliac vein has because of the patient’s immunodeficient status. Three months of treatment using single-dose edoxaban (30 mg daily) resulted in complete resolution of the thrombus. This is the first report demonstrating that single-dose edoxaban without acute-phase parenteral anticoagulation is effective in the treatment of iliac vein compression.

Conclusions

A single-dose direct oral anti-coagulant without acute-phase parenteral anticoagulation is effective for mechanical compression

May-Thurner syndrome: MDCT findings and clinical correlates

May-Thurner syndrome (MTS) is a venous compression syndrome in which the left common iliac vein is compressed between the lower lumbar spine and the right common iliac artery. While asymptomatic compression is very common, the process can lead to morbidity in selected individuals, most commonly deep venous thrombosis (DVT) and the sequelae thereof. Radiologists must recognize the diagnosis because of the unique management, which differs from DVT without iliac vein compression. The current pictorial essay will review the pathophysiology, imaging, and treatment of MTS.

Editor's Choice-- A Systematic Review of Endovenous Stenting in Chronic Venous Disease Secondary to Iliac Vein Obstruction

OBJECTIVES

Deep endovenous stenting to relieve chronic venous disease (CVD) secondary to post-thrombotic or non-thrombotic iliac vein obstruction is becoming increasingly well described. However, current and adequately reported systematic reviews on the topic are lacking. This report aimed to produce a systematic review and meta-analysis of the available data, reported to the Preferred Reporting Items for Systematic reviews and Meta-Analyses guideline.

METHODS

MEDLINE, EMBASE, and the Cochrane Central Register for Controlled Trials databases and key references were searched.

RESULTS

Sixteen studies were included (14 before-and-after studies, 1 controlled before-and-after study, and 1 case series) encompassing successful deep venous stenting in 2,373 and 2,586 post-thrombotic or non-thrombotic limbs and patients respectively. The data were too heterogeneous to perform a meta-analysis. There were significant improvements in validated measures of the severity of CVD and venous disease-specific quality of life. Persistent ulcer healing rates ranged from 56% to 100% in limbs that had often already failed conservative management. Primary and secondary stent patency ranged from 32% to 98.7% and 66%-96% respectively. The major complication rate ranged from 0 to 8.7% per stented limb. A GRADE assessment demonstrated the quality of the evidence for five outcomes to be "Very Low" and one to be "Low" (ulcer healing).

CONCLUSIONS

The quality of evidence to support the use of deep venous stenting to treat obstructive CVD is currently weak. The treatment does however appear promising and is safe and should therefore be considered as a treatment option while the evidence base is improved.

Compression of the right iliac vein in asymptomatic subjects and patients with iliofemoral deep vein thrombosis

OBJECTIVE

To evaluate right iliac vein and left iliac vein compression in asymptomatic subjects, right-sided and left-sided iliofemoral deep vein thrombosis patients.

METHODS

A retrospective analysis of records and computed tomography images was conducted in 200 asymptomatic subjects (male:female, 100:100). A prospective analysis was conducted in 79 consecutive deep vein thrombosis patients (left:right deep vein thrombosis, 47:32) who had undergone contrast-enhanced computed tomography examination. The minor diameter and percentage compression of the iliac vein were evaluated.

RESULTS

In asymptomatic subjects, 13.5% had right iliac vein compression >50%, 2.0% had right iliac vein compression >70%, mean compression was 23.48%; 45.0% had left iliac vein compression >50% and 17.0% had left iliac vein compression >70%, mean compression was 47.58%. Right iliac vein sandwiched between the right external iliac artery and the right internal iliac artery was the most common compression pattern (59.26%). Males had higher right iliac vein compression than the females (male:female, 26.29%:20.68%, P < 0.001). Mean percentage compression of the right iliac vein was higher in right deep vein thrombosis patients than in left deep vein thrombosis patients (right:left deep vein thrombosis, 48.54%:22.29%, P < 0.001).

CONCLUSION

Similar to left iliac vein compression, right iliac vein compression was a frequent imaging finding in CT and represented a normal anatomic pattern. Right deep vein thrombosis patients had more serious right iliac vein compression than left deep vein thrombosis patients, and further research is required on the association of right iliac vein compression with right iliofemoral deep vein thrombosis.

Short-Term Clinical Experience with a Dedicated Venous Nitinol Stent: Initial Results with the Sinus-Venous Stent

OBJECTIVE

Deep venous stenting has become the primary treatment option for chronic venous obstructive disease, both for iliac vein compression and post-thrombotic venous lesions. Until recently, only stents aimed at arterial pathology were used, because no dedicated venous stents were available. However, three such stents have now become available. These venous stents are characterized by increased length, diameter, flexibility, and radial force. This study reports an early experience with one of these devices; the sinus Venous stent (OptiMed GmbH, Ettlingen, Germany).

METHODS

Between March 2012 and July 2014, 75 patients were treated with the sinus Venous stent: 35 cases of iliac vein compression syndrome and 40 cases of unilateral chronic obstruction in post-thrombotic syndrome (PTS). Diagnosis of relevant obstruction was made using clinical evaluation, duplex ultrasound, and magnetic resonance venography. Patency during follow up was assessed with duplex ultrasound. Clinical improvement was assessed by VCSS, Villalta score, rate of ulcer healing, and improvement of venous claudication.

RESULTS

The cumulative patency rates at 3, 6, and 12 months were 99%, 96%, and 92%, respectively. The cumulative assisted primary patency rates were 99% at 3, 6, and 12 months. The cumulative secondary patency rate at 12 months was 100%. Differences exist in patency rate between the subgroups of non-thrombotic and post-thrombotic, with the first showing no re-occlusions. All re-thromboses in the PTS group were treated by ancillary treatment modalities. VCSS and Villalta score decreased significantly after stenting, as did venous claudication. Morbidity was low without clinically relevant pulmonary embolism, and mortality was nil. Although two out of seven ulcers healed temporarily, no ulcer remained healed at 12 months follow up.

CONCLUSION

Short-term clinical results using the sinus Venous stent are excellent, with significant symptom reduction, low morbidity rates, and no mortality. Loss of stent patency is seen less often compared with arterial stents described in the literature.

Stent Compression in Iliac Vein Compression Syndrome Associated with Acute Ilio-Femoral Deep Vein Thrombosis

OBJECTIVE

This study was conducted to evaluate stent compression in iliac vein compression syndrome (IVCS) and to identify its association with stent patency.

MATERIALS AND METHODS

Between May 2005 and June 2014, after stent placement for the treatment of IVCS with acute ilio-femoral deep vein thrombosis, follow-up CT venography was performed in 48 patients (35 women, 13 men; age range 23-87 years; median age 56 years). Using follow-up CT venography, the degree of the stent compression was calculated and used to divide patients into two groups. Possible factors associated with stent compression and patency were evaluated. The cumulative degree of stent compression and patency rate were analyzed.

RESULTS

All of the stents used were laser-cut nitinol stents. The proportion of limbs showing significant stent compression was 33%. Fifty-six percent of limbs in the significant stent compression group developed stent occlusion. On the other hand, only 9% of limbs in the insignificant stent compression group developed stent occlusion. Significant stent compression was inversely correlated with stent patency (p < 0.001). The median patency period evaluated with Kaplan-Meier analysis was 20.0 months for patients with significant stent compression. Other factors including gender, age, and type of stent were not correlated with stent patency. Significant stent compression occurred most frequently (87.5%) at the upper end of the stent (ilio-caval junction).

CONCLUSION

Significant compression of nitinol stents placed in IVCS highly affects stent patency. Therefore, in order to prevent stent compression in IVCS, nitinol stents with higher radial resistive force may be required.

Ipsilateral leg swelling after renal transplantation as an alarming sign of Iliac vein stenosis

Iliac vein stenosis is a rare vascular complication of renal transplantation that may compromise allograft function if not recognized and corrected in a timely fashion. Because chronic venous stenosis may remain undiagnosed for several years, a high index of suspicion should be maintained until diagnosing this rare disease. A 56-year-old renal transplant recipient presented with unilateral leg swelling and renal dysfunction 16 years after transplantation. Computed tomography excluded deep vein thrombosis and revealed tight iliac vein stenosis on the side of the renal transplant. Following angiographic confirmation of the stenosis, endovascular treatment was successfully performed with a purposefully designed, self-expanding, venous stent. Ipsilateral leg swelling is an alarming sign for the diagnosis of iliac vein stenosis after renal transplantation. Percutaneous intervention with venous stent placement seems to be a safe and effective treatment of this rare condition.

Percutaneous manual aspiration thrombectomy followed by stenting for iliac vein compression syndrome with secondary acute isolated iliofemoral deep vein thrombosis: a prospective study of single-session endovascular protocol

OBJECTIVE

To evaluate the feasibility, safety, and effectiveness of single-session endovascular treatment with manual aspiration thrombectomy (MAT) as the first-line method of thrombus removal for iliac vein compression syndrome (IVCS) with secondary acute isolated iliofemoral deep vein thrombosis (DVT).

METHODS

This was a prospective clinical study. Twenty-six patients (19 women, 7 men, mean age 54 years) with left-sided acute iliac-common femoral DVT secondary to IVCS were enrolled. All patients presented with leg swelling or pains. Endovascular treatment, consisting of MAT, balloon angioplasty, and stent placement, was performed in the same setting. Overnight antegrade thrombolysis was performed in patients with residual thrombus after MAT. Patients were followed up by ultrasonography. The mean follow-up period was 17.8 months (12-25 months).

RESULTS

Single-session endovascular procedures were performed successfully in all patients. The mean procedure time was 67 minutes (ranging from 45 to 90 minutes). Complete thrombus removal, including almost 100% of removal in 24 patients and little residual thrombus (<5%) in two, was achieved after repeated MAT. Thrombolysis was used in these two patients. Complete symptomatic relief was achieved in 25 patients (96%) and partial relief in one. The hospital stay ranged from 2 to 4 days (mean 2.7 days). Recurrent thrombosis within the stent was observed in one case and recanalized with thrombolysis. The 1-year primary and secondary patency rate was 96% and 100%, respectively. No symptomatic pulmonary embolization, bleeding, and venous reflux were observed. Five patients complained about transitory low back pains during balloon angioplasty.

CONCLUSION

Single-session endovascular treatment with MAT as the first-line thrombus removal method is feasible, safe, and effective for IVCS with secondary acute isolated iliofemoral DVT. Although limited, our experience suggests that patients thought to be at high risk of bleeding may be candidates for the present single-session endovascular protocol.

Endovascular treatment for iliac vein compression syndrome: a comparison between the presence and absence of secondary thrombosis

Objective

To evaluate the value of early identification and endovascular treatment of iliac vein compression syndrome (IVCS), with or without deep vein thrombosis (DVT).

Materials and Methods

Three groups of patients, IVCS without DVT (group 1, n = 39), IVCS with fresh thrombosis (group 2, n = 52) and IVCS with non-fresh thrombosis (group 3, n = 34) were detected by Doppler ultrasonography, magnetic resonance venography, computed tomography or venography. The fresh venous thrombosis were treated by aspiration and thrombectomy, whereas the iliac vein compression per se were treated with a self-expandable stent. In cases with fresh thrombus, the inferior vena cava filter was inserted before the thrombosis suction, mechanical thrombus ablation, percutaneous transluminal angioplasty, stenting or transcatheter thrombolysis.

Results

Stenting was performed in 111 patients (38 of 39 group 1 patients and 73 of 86 group 2 or 3 patients). The stenting was tried in one of group 1 and in three of group 2 or 3 patients only to fail. The initial patency rates were 95% (group 1), 89% (group 2) and 65% (group 3), respectively and were significantly different (p = 0.001). Further, the six month patency rates were 93% (group 1), 83% (group 2) and 50% (group 3), respectively, and were similarly significantly different (p = 0.001). Both the initial and six month patency rates in the IVCS patients (without thrombosis or with fresh thrombosis), were significantly greater than the patency rates of IVCS patients with non-fresh thrombosis.

Conclusion

From the cases examined, the study suggests that endovascular treatment of IVCS, with or without thrombosis, is effective.