Evaluation of 3-dimensional rotational venography for the diagnosis of non-thrombotic iliac venous lesion

Background

The purpose of this study was to determine the technical feasibility and safety of 3D rotational venography (3D-RV) in the diagnosis of non-thrombotic iliac vein lesions compared with traditional 2D-digital subtraction angiography (2-DSA).

Methods

The general epidemiological data (including age, gender), clinical manifestations (including major symptom, affected extremity, CEAP classification, comorbidity, stenosis rate), and intra-operative findings (iliac vein indentation position, collateral circulation, procedure time, X-rays dose, contrast agent dosage) of 61 NIVL patients who were assessed by 3D-RV and traditional 2-DSA between October 2018 to October 2022 were obtained and analyzed.

Results

A total of 61 consecutive patients with symptomatic NIVL from our institution were enrolled in this study. With the aggravation of iliac vein stenosis, the proportion of indicators such as contralateral formation and iliac vein compression indentation reflecting the severity of compression under 3D-RV reconstruction increased significantly. Also, significant differences were observed between the 3D-RV and 2-DSA groups concerning procedure time (10.56 ± 0.09 s vs. 12.59 ± 0.37 s; p < 0.01), X-ray dose (41.25 ± 0.21 mGy vs. 81.59 ± 1.69 mGy; p < 0.01) and contrast agent dosage (21.48 ± 0.24 mL vs. 33.69 ± 0.72 mL; p < 0.01). Contralateral iliac vein imaging (p = 0.002), pelvic collateral vein imaging (p = 0.03), and external iliac vein indentation (p = 0.001) were found to influence the severity of iliac vein compression.

Conclusion

3D-RV can display dynamic stereo image information of NIVL, augmenting the information obtained from traditional 2-DSA. Contralateral iliac vein imaging, pelvic collateral vein imaging, and external iliac vein indentation can be used to evaluate the severity of iliac vein compression to some extent.

Preliminary study of hemodynamics of iliac venous compression syndrome using magnetic resonance imaging

OBJECTIVE

In clinical practice, the degree of iliac vein stenosis has often been inconsistent with the symptoms of chronic venous disease (CVD). To the best of our knowledge, no clinical studies have evaluated the hemodynamic changes associated with iliac vein stenosis. Magnetic resonance imaging (MRI) can noninvasively provide hemodynamic information. In the present study, we assessed the degree of stenosis associated with iliac venous compression syndrome and the relationships between iliac venous compression syndrome-induced, MRI-determined hemodynamic changes and lower limb symptoms.

METHODS

Stenosis severity, the presence of collateral vessels, and flow rate (FR) differences between the common and external iliac veins secondary to iliac vein stenosis were measured using MRI in 69 patients with CVD. Villalta scores were used as a measure of symptom severity for all patients, and the percentage of change in the Villalta score was used as a measure of symptom improvement for the patients who had received iliac vein stents. Symptom severity for all patients, a subgroup of patients with iliac vein compression (affected limbs), and a group of patients with unilateral iliac vein compression treated with stents was correlated with stenosis, differences in the external and common iliac vein FRs (<0-mL/s group, indicating stenosis-induced decreased common iliac vein flow, and ≥0-mL/s group), and stenosis-induced collateral vessel formation.

RESULTS

Iliac vein stenosis severity and FR differences in all affected limbs were correlated with the Villalta scores of the affected limbs (stenosis: r = 0.38, P < .001, n = 95; FR difference: r = -0.44, P < .001). In the unilateral compression subgroup, stenosis severity, FR differences, and the presence of collateral vessels were not associated with significant changes in contralateral symptoms. In the endovascular treatment subgroup, both lower limbs exhibited significant improvement after stent implantation (affected limb symptom remission, 64.6% ± 18.2%, n = 15; contralateral limb symptom remission, 49.1% ± 29.1%, n = 11). The rate of symptom remission was greater for patients with decreased iliac vein flow in the affected limbs (<0-mL/s group: 74.6% ± 16.4%, n = 7; ≥0-mL/s group: 52.2% ± 16.6%, n = 6; P = .032).

CONCLUSIONS

Iliac vein stenosis, the presence of collateral vessels, and decreased FRs due to stenosis correlated significantly with lower limb symptom severity. Endovascular treatment yielded good outcomes in patients with stenosis >50%. A decreased iliac venous FR could indicate a better response to stent implantation and could be used in the diagnosis and guiding decisions to treat iliac venous compression.

Diagnosis and Treatment of Nonthrombotic Right Iliac Vein Compression Syndrome

BACKGROUND

The anatomical etiology of right iliac vein compression syndrome (RIVCS) differs from that of left iliac vein compression syndrome. This study aimed to investigate the clinical features and therapeutic characteristics of RIVCS.

METHODS

Sixteen patients with nonthrombotic RIVCS were admitted to our hospital from May 2013 to July 2017. All patients underwent computed tomography venography (CTV) examinations of the right lower limb, which indicated that the right iliac veins were compressed by extrinsic structures. RIVCS was divided into 3 types according to the CTV findings. Stenting was conducted in patients with the appropriate indications. The superficial varicose veins in the lower limbs were simultaneously treated during endovascular treatment in a compound operating room. Antiplatelet therapy was administered after discharge.

RESULTS

Most RIVCS cases were types II and III, and the most frequently compressed segments were the middle and distal parts of the iliac vein. Most stents did not require stretching into the inferior vena cava and therefore seldom affected contralateral blood flow. Fifteen patients required stenting; the diameters of the stents ranged from 10 to 16 mm. All symptoms were alleviated, and the ulcers healed postoperatively. The remaining single patient with superficial varicose veins did not have an indication for endovascular therapy. During follow-up, all patients were symptom free, and the stents showed excellent patency.

CONCLUSIONS

CTV is a simple, accurate, and important method for diagnosing RIVCS. Endovascular therapy is an effective therapeutic method for RIVCS. Compared with the left side, stent implantation for RIVCS is safer and has fewer effects on contralateral blood flow.

Illusory Angiographic Signs of Significant Iliac Vein Compression in Healthy Volunteers

OBJECTIVE

Iliac vein compression syndrome can cause severe leg symptoms. In clinical practice, it remains a challenge to differentiate which compression is clinically relevant. The aim of the current study was to assess the general treatment indications and the prevalence of angiographic signs of iliac vein compression in a group of healthy participants.

METHODS

This was a prospective cohort study. A total of 20 healthy volunteers (median age 21, range 20-22 years) were recruited through advertisement and underwent angiography of the iliac veins. When no compression signs were present, a balloon occlusion was performed. Additionally, a 10 item survey regarding indications for venous stenting was developed and sent to 30 vascular specialists treating patients with deep venous obstruction.

RESULTS

In 16 (80%) participants, at least two signs indicative of May-Thurner compression were seen. In three (15%) subjects, narrowing of the common iliac vein without collaterals was shown and one (5%) did not show any signs of obstruction. In 23 (70%) of the survey responders, collaterals were found to be the most typical sign indicative of significant venous obstruction. An angiographic sign of >50% compression was found to be an indication to stent in 55% of responders.

CONCLUSION

This study demonstrates a remarkably high percentage of generally accepted signs of significant iliac vein obstruction (May-Thurner compression) on venography in healthy young subjects. Diagnosis of true iliac vein obstruction remains a major challenge, which mostly leans on improvement of clinical symptoms rather than imaging findings. Treating the patient rather than the image seems to be a valid principle all the more.

Novel Compliant Scaffold with Specific Design for Venous System: Results of a Porcine Model Study

Background

Stenting has become the first-line treatment of obstructive venous disease because of poor results of balloon angioplasty. This preclinical study aimed to investigate the safety and efficacy profile of a novel compliant venous scaffold (CVS) denominated Petalo CVS, specifically designed for venous diseases.

Materials and Methods

Twelve healthy pigs weighing 90 kg were used to test Petalo CVS. The devices were implanted into the internal jugular veins (IJVs) using a femoral vein percutaneous approach. The safety profile including the success rate of device releasing, anchoring, and positioning was evaluated immediately. Fracture, migration, primary patency, and endothelial response were assessed at 1, 2, 3, and 6 months after the study procedure.

Results

A total of 32 devices were successfully released in both IJVs. No procedure- or device-related complications were reported, and all pigs successfully completed the different scheduled follow-up periods. The primary patency rate was 100%, and no fracture or migration of the device into the brachiocephalic trunk was reported. Histological examination revealed only minimal lesions with minimal or absent inflammatory reaction surrounding the incorporated metallic rods.

Conclusions

This porcine model study showed a promising safety and efficacy profile of Petalo CVS, a novel endovenous device based on specific concepts.

[Diagnostics and endovascular treatment of venous diseases]

In venous disease, acute thromboses and chronic venous insufficiency have the highest health economics relevance. Duplex sonography is the first line diagnostic assessment tool, while cross-sectional imaging is employed as a supplementary method. Due to the availability and examination times computed tomography is preferred in the emergency setting and is supplemented by magnetic resonance imaging (MRI) for specific questions. Endovascular treatment procedures are increasingly becoming available in addition to classical conservative treatment methods.

A comparison of magnetic resonance venography findings and venous occlusion plethysmography variables in postthrombotic syndrome

Objective The relation between venous morphology and venous function in postthrombotic syndrome is poorly understood. The aim of this study was to compare obstruction and collateralization as seen with magnetic resonance venography with variables of venous occlusion plethysmography in patients with postthrombotic syndrome. Methods Medical records, magnetic resonance venography and venous occlusion plethysmography data were analyzed in 28 patients (33 legs). Magnetic resonance venography images were scored for degree of obstruction and collateralization in segments of pelvic and abdominal veins and correlated to venous occlusion plethysmography data. Results Obstruction of the inferior vena cava correlated with an overall increase of collaterals ( p < 0.001). The summary scores of collaterals or obstructions did not correlate with venous occlusion plethysmography variables. Relative expelled volume at 4 s correlated inversely with obstruction of the inferior vena cava ( p = 0.045) and vertebral collateralization ( p = 0.033). Conclusions Modest correlations were found between magnetic resonance venography scores and venous occlusion plethysmography variables. Prospective studies with refined scoring and magnetic resonance venography techniques may increase our knowledge further.

The predictive value of haemodynamic parameters for outcome of deep venous reconstructions in patients with chronic deep vein obstruction - A systematic review

Objective The aim of this study was to investigate the predictive value of haemodynamic parameters on success of stenting or bypass surgery in patients with non-thrombotic or post-thrombotic deep venous obstruction. Methods EMBASE, MEDLINE and trial registries were searched up to 5 February 2016. Studies needed to investigate stenting or bypass surgery in patients with post-thrombotic obstruction or stenting for non-thrombotic iliac vein compression. Haemodynamic data needed to be available with prognostic analysis for success of treatment. Two authors, independently, selected studies and extracted data with risk bias assessment using the Quality in Prognosis Studies tool. Results Two studies using stenting and two using bypass surgery were included. Three investigated plethysmography, though results varied and confounding was not properly taken into account. Dorsal foot vein pressure and venous refill times appeared to be of influence in one study, though confounding by deep vein incompetence was likely. Another investigated femoral-central pressure gradients without finding statistical significance, though sample size was small without details on statistical methodology. Reduced femoral inflow was found to be a predictor for stent stenosis or occlusion in one study, though patients also received additional surgery to improve stent inflow. Data on prediction of haemodynamic parameters for stenting of non-thrombotic iliac vein compression were not available. Conclusions Data on the predictive value of haemodynamic parameters for success of treatment in deep venous obstructive disease are scant and of poor quality. Plethysmography does not seem to be of value in predicting outcome of stenting or bypass surgery in post-thrombotic disease. The relevance of pressure-related parameters is unclear. Reduced flow into the common femoral vein seems to be predictive for in-stent stenosis or occlusion. Further research into the predictive effect of haemodynamic parameters is warranted and the possibility of developing new techniques that evaluate various haemodynamic aspects should be explored.

Prevalence of Non-thrombotic Iliac Vein Lesions in Patients with Unilateral Primary Varicose Veins

OBJECTIVES

A role of non-thrombotic iliac vein lesions (NIVLs) in the development of primary varicose veins (PVVs) has not been studied. It seems that intravascular ultrasound (IVUS) is the most accurate method to diagnose these lesions. The aim of the study was to investigate the association between the presence of NIVLs and PVVs and the frequency of NIVLs in asymptomatic and PVV limbs.

DESIGN

This was an observational study.

MATERIALS

Thirty-three patients with unilateral PVV and great saphenous vein incompetence who were qualified for surgical treatment were analyzed. Nineteen patients (57%) presented with varicose veins on the right side.

METHODS

During varicose vein surgery, IVUS of the iliac veins and the inferior vena cava was performed. In all patients the iliocaval outflow was interrogated by IVUS in both the limb with and without PVVs. The PVV side was accessed through the surgically exposed sapheno-femoral junction and the non-PVV side was accessed by an ultrasound guided percutaneous puncture of the common femoral vein. In both the common iliac (CIVs) and the external iliac veins (EIVs) the minimal and reference lumen area were measured and the percentage stenosis calculated.

RESULTS

There were no intra- or post-procedural complications. The minimal lumen area (MLA) was smaller and the stenosis of the CIV was greater on the left side than the right: median 57 and 108 mm(2) (p = 0.001) and 69 and 34% (p < 0.001), respectively. However when the PVV and non-PVV sides were compared, no statistically significant differences of MLA or stenosis of the CIV were found: 88 and 67 mm(2) (p = 0.38) and 44% and 51% (p = 0.40), respectively. With regard to EIVs, no statistically significant differences in either MLA or stenosis between the left and right and PVV and non-PVV sides were found. The frequency of ≥50% stenosis of CIV and EIV in the PVV limbs and the non-PVV limbs was 42% and 48% and 51% and 39%, respectively.

CONCLUSIONS

NIVLs are common in patients with PVV but do not seem to be associated with the presence of ipsilateral PVV.