Effect of Stent Strut Interval on Neointima Formation After Venous Stenting in an Ovine Model.

OBJECTIVE: The impact of stent design on venous patency is not well studied. The purpose of this study was to investigate the effect of stent material burden on endothelial coverage of stented venous segments, which may contribute to vessel healing and patency. METHODS: Segmented self expanding bare nitinol stents (18 × 50 mm) comprising 5 mm long attached metallic rings separated by 2, 5, or 8 mm gaps were implanted in the inferior vena cava (IVC) of 10 sheep. These stents were designed and manufactured for the purposes of this study. At six, 12, and 24 weeks after implantation the animals were euthanised and the stented vessels harvested for histomorphometric analysis. Three sections from the metallic part as well as the gaps between the struts were reviewed for quantification of endothelialisation after six, 12, and 24 weeks. The intimal thickness over and between the stent struts was measured. The endothelialisation score (graded from 1 for complete luminal endothelialisation to 5 for absence of endothelial cells) was determined. RESULTS: All stents were successfully deployed and all 10 sheep survived until the time of harvesting. Macroscopic inspection after 24 weeks showed only partial endothelialisation over stents with 2 mm and 5 mm skipped segments, whereas the stents with 8 mm skipped segments were totally incorporated into the vein wall. After 24 weeks, the mean (SD) neointimal thicknesses over stent struts with 2 mm, 5 mm, and 8 mm skipped segments were 254.0 (51.6), 182.2 (98.1), and 194.6 (101.1) µm, respectively. Comparison of endothelialisation scores of stents over time showed statistically significantly better endothelialisation over stents with 8 mm gaps after 12 and 24 weeks. CONCLUSION: Stent designs providing structural support to veins with larger gaps between the scaffold material appear to lead to faster and more complete endothelialisation as well as a thinner intimal layer.

Iliocaval Skip Stent Reconstruction Technique for Chronic Bilateral Iliocaval Venous Occlusion.

PURPOSE: To report safety and efficacy of a skip stent technique using nitinol stents in patients with chronic bilateral iliocaval venous occlusions. MATERIALS AND METHODS: A retrospective analysis of 48 consecutive patients (32 men; mean age, 40.7 years; age range, 18-68 years) with chronic bilateral iliocaval obstructions treated using a nonoverlapping stent technique was conducted at a single center. None of the patients had May-Thurner syndrome. Iliocaval confluence was treated by deploying a nitinol stent in inferior vena cava (IVC) and a nitinol stent in each common iliac vein close to the caval stent. Patency of stents was assessed by duplex US at 2 weeks, 3 months, and 6 months and yearly thereafter. RESULTS: Recanalization and stent reconstruction was technically successful in 47 (98%) patients. The sinus-XL venous stent was used to treat IVC (95 [100%]). Common iliac and external iliac veins were treated with sinus-Venous and VENOVO stents (80 [83%] and 16 [17%] limbs, respectively). External iliac and common femoral veins were treated with sinus-Venous and VENOVO stents (83 [92%] and 7 [18%] limbs, respectively). Early thrombosis (< 30 days) of the iliac vein with stent occurred in 2 limbs. Cumulative primary, assisted primary, and secondary patency rates at 30 months were 74%, 83%, and 97%. CONCLUSIONS: Findings of this study suggest that leaving a skipped lesion at the level of iliocaval confluence may not adversely affect stent patency. Patency rates were comparable with other reported techniques of stent reconstruction at the level of iliocaval confluence.

Prevalence of venous obstructions in (recurrent) venous thromboembolism: a case-control study.

BACKGROUND: The role of venous obstructions as a risk factor for recurrent venous thromboembolism has never been evaluated. This study aimed to determine whether there is a difference in prevalence of venous obstructions between patients with and without recurrent venous thromboembolism. Furthermore, its influence on the development of post-thrombotic syndrome and patient-reported quality of life was assessed. METHODS: This matched nested case-control study included 32 patients with recurrent venous thromboembolism (26 recurrent deep-vein thrombosis and 6 pulmonary embolism) from an existing prospective cohort of deep-vein thrombosis patients and compared them to 24 age and sex matched deep-vein thrombosis patients without recurrent venous thromboembolism. All participants received standard post-thrombotic management and underwent an additional extensive duplex ultrasonography. Post-thrombotic syndrome was assessed by the Villalta-scale and quality of life was measured using the SF36v2 and VEINES-QOL/Sym-questionnaires. RESULTS: Venous obstruction was found in 6 patients (18.8%) with recurrent venous thromboembolism compared to 5 patients (20.8%) without recurrent venous thromboembolism (Odds ratio 0.88, 95%CI 0.23-3.30, p = 1.000). After a median follow-up of 60.0 months (IQR 41.3-103.5) the mean Villalta-score was 5.55 ± 3.02 versus 5.26 ± 2.63 (p = 0.909) and post-thrombotic syndrome developed in 20 (62.5%) versus 14 (58.3%) patients, respectively (Odds ratio 1.19, 95%CI 0.40-3.51, p = 0.752). If venous obstruction was present, it was mainly located in the common iliac vein (n = 7, 63.6%). In patients with an objectified venous obstruction the mean Villalta-score was 5.11 ± 2.80 versus 5.49 ± 2.87 in patients without venous obstruction (p = 0.639). Post-thrombotic syndrome developed in 6 (54.5%) versus 28 (62.2%) patients, respectively (Odds ratio 1.37, 95%CI 0.36-5.20, p = 0.736). No significant differences were seen regarding patient-reported quality of life between either groups. CONCLUSIONS: In this exploratory case-control study patients with recurrent venous thromboembolism did not have a higher prevalence of venous obstruction compared to patients without recurrent venous thromboembolism. The presence of recurrent venous thromboembolism or venous obstruction had no impact on the development of post-thrombotic syndrome or the patient-reported quality of life.

Ultrasound-accelerated catheter-directed thrombolysis versus anticoagulation for the prevention of post-thrombotic syndrome (CAVA): a single-blind, multicentre, randomised trial.

BACKGROUND: Early thrombus removal might prevent post-thrombotic syndrome by preserving venous function and restoring flow. Previous trials comparing additional catheter-directed thrombolysis to standard treatment showed conflicting outcomes. We aimed to assess the benefit of additional ultrasound-accelerated catheter-directed thrombolysis for the prevention of post-thrombotic syndrome compared with standard therapy in patients with iliofemoral deep-vein thrombosis. METHODS: We did a multicentre, randomised, single-blind, allocation-concealed, parallel group, superiority trial in 15 hospitals in the Netherlands. Patients aged 18-85 years with a first-time acute iliofemoral deep-vein thrombosis and symptoms for no more than 14 days were randomly assigned (1:1) to either standard treatment with additional ultrasound-accelerated catheter-directed thrombolysis or standard treatment alone. Randomisation was done with a web-based automatic programme and a random varying block size (2-12), stratified by age and centre. Standard treatment included anticoagulant therapy, compression therapy (knee-high elastic compression stockings; 30-40 mmHg), and early ambulation. Additional ultrasound-accelerated catheter-directed thrombolysis was done with urokinase with a starting bolus of 250 000 international units (IU) in 10 mL NaCl followed by a continuous dose of 100 000 IU/h for a maximum of 96 h through the Ekos Endowave-system. Adjunctive percutaneous transluminal angioplasty, thrombosuction, or stenting was performed at the discretion of the physician who performed the intervention. The primary outcome was the proportion of patients with post-thrombotic syndrome at 12 months diagnosed according to the original Villalta criteria-a Villalta-score of at least 5 on two consecutive occasions at least 3 months apart or the occurrence of venous ulceration-and was assessed in a modified intention-to-treat population of all randomly assigned patients who passed screening and started treatment. The safety analysis was assessed in the same modified intention-to-treat population. This study is complete and is registered at ClinicalTrials.gov, NCT00970619. FINDINGS: Between May 28, 2010, and Sept 18, 2017, 184 patients were randomly assigned to either additional ultrasound-accelerated catheter-directed thrombolysis (n=91) or standard treatment alone (n=93). Exclusion because of screening failure or early withdrawal of informed consent resulted in 77 patients in the intervention group and 75 in the standard treatment group starting allocated treatment. Median follow-up was 12·0 months (IQR 6·0-12·0). 12-month post-thrombotic syndrome occurred in 22 (29%) patients allocated to additional treatment versus 26 (35%) patients receiving standard treatment alone (odds ratio 0·75 [95% CI 0·38 to 1·50]; p=0·42). Major bleeding occurred in four (5%) patients in the intervention group, with associated neuropraxia or the peroneal nerve in one patient, and no events in the standard treatment group. No serious adverse events occurred. None of the four deaths (one [1%] in the intervention group vs three [4%] in the standard treatment group) were treatment related. INTERPRETATION: This study showed that additional ultrasound-accelerated catheter-directed thrombolysis does not change the risk of post-thrombotic syndrome 1 year after acute iliofemoral deep-vein thrombosis compared with standard therapy alone. Although this trial is inconclusive, the outcome suggests the possibility of a moderate beneficial effect with additional ultrasound-accelerated catheter-directed thrombolysis. Further research is therefore warranted to better understand this outcome in the context of previous trials, preferably by combining the available evidence in an individual patient data meta-analysis. FUNDING: The Netherlands Organisation for Health Research and Development (ZonMw), Maastricht University Medical Centre, BTG-Interventional Medicine.

Closed incisional negative pressure therapy may reduce surgical site infection rate following endophlebectomy with complementary polytetrafluoroethylene arteriovenous fistula of the common femoral vein.

OBJECTIVE: Surgical desobliteration or endophlebectomy of the common femoral vein during deep venous recanalization with complementary polytetrafluoroethylene (PTFE) arteriovenous fistula (AVF), may lead to higher rates of surgical site infection (SSI). It has been reported that closed incisional negative pressure wound therapy (cINPT) may decrease SSI rates after different surgical procedures. The aim of this study was to determine the potential effect of cINPT on the SSI rate of femoral endophlebectomy with a complimentary PTFE AVF. METHODS: Patients with recanalization of the femoral-iliac veins and femoral endophlebectomy with a complementary PTFE AVF and postoperative cINPT were identified. SSI, patency, and complication rates were analyzed. RESULTS: This study included 65 patients with a mean age of 41 ± 14 years. The mean procedure time was 240 ± 11.9 minutes. Primary patency rate was 69.2% and secondary patency rate was 78.4%. SSI classified as Szilagyi I, II, and III occurred in 7.6% (n = 5), 3% (n = 2), and 7.6% (n = 5), respectively, with an overall SSI rate of 18.2%. Surgical wound revision with the application of a vacuum pump was required in 10.7% (n = 7). A multivariate analysis showed that the duration of the surgical procedure (P = .003) as well as lymphatic fistulas (P = .044) to have a significant impact on the SSI rate. CONCLUSIONS: Endophlebectomy with complementary PTFE AVF of the femoral vein is related to an increased rate of lymphatic leakage and SSI. Lymphatic fistula and the duration of surgery could be assessed as relevant influencing factors of SSI. Application of cINPT in this surgical setting may reduce the SSI rate. Despite this potential improvement, SSI rates still limit the clinical success of a deep venous recanalization.

Update on diagnosis and treatment strategies in patients with post-thrombotic syndrome due to chronic venous obstruction and role of endovenous recanalization.

OBJECTIVE: After a first episode of lower extremity deep venous thrombosis, post-thrombotic syndrome (PTS) develops in 20% to 50% of patients despite adequate anticoagulation. Symptoms of PTS can vary from leg swelling to venous ulceration with disabling venous claudication. It significantly affects the patient's quality of life and has considerable socioeconomic consequences. This review gives an update on diagnosis and current treatment strategies in patients with PTS due to chronic venous obstruction, in particular regarding the role of endovenous procedures. METHODS: This review article is based on a selective literature search in PubMed and the Cochrane Library. The terms "postthrombotic syndrome," "post-thrombotic syndrome," "chronic venous obstruction," "venous outflow obstruction," and "venous stent" were used as keywords. Selected publications addressed the diagnosis of and therapy for PTS. Acute deep venous thrombosis, thrombolysis, case reports, complications as a result of caval vein filters, animal experiments, PTS of the upper extremity, and PTS in children were excluded. RESULTS: In addition to conservative treatment of PTS, the following invasive procedures are also available: open surgical reconstructions, hybrid procedures, and endovenous recanalization of the occluded iliocaval venous tract with stent angioplasty. Since introduction of dedicated venous stents in 2012, technical success, patency rates, and improvement in quality of life have been at least as good as results of open surgical reconstruction if not better. CONCLUSIONS: First-line treatment should be conservative therapy. In case of therapy-resistant PTS with poor quality of life, the possibility of an invasive treatment should be evaluated. All invasive procedures are recommended with low levels of evidence. Therefore, deciding on an invasive treatment and type of procedure should be made individually. Because PTS is rarely a threat to life or limb, a minimally invasive treatment is preferred. Therefore, endovenous recanalization appears to be appropriate as the therapy of choice. In patients with involvement of the femoral confluence, endophlebectomy of the common femoral vein in addition to venous recanalization is inevitable to ensure an adequate inflow into the recanalized venous tract. It also secures a sufficient drainage of blood from the peripheral venous system. Because this hybrid procedure is burdened with a significantly higher risk of complications, strict criteria must be fulfilled to legitimize the indication for this procedure. For the best possible results to be achieved, the following perioperative and postoperative management must be considered: therapeutic anticoagulation, early mobilization, compression therapy, and systematic follow-up with duplex ultrasound.

Detecting stent geometry changes after venous recanalization using duplex ultrasound.

BACKGROUND: Patients with post-thrombotic syndrome due to chronic venous obstruction and resistant to conservative management can benefit from endovenous revascularization. The current study investigated the usefulness of duplex ultrasound in monitoring the stent changes over the time. METHOD: All duplex ultrasound images of treated patients were reviewed retrospectively. The stent diameter and area during the follow-up visits have been analyzed. RESULT: A total of 210 stents were placed in 137 limbs. Duplex ultrasound findings showed a decrease in area of stent in all patients (mean: 0.69 cm2). Reduction of stent area over the time was a predictor of stent patency (odds ratio: 0.910; confidence interval: 0.832-0.997). CONCLUSION: Duplex ultrasound has sufficient accuracy in detection of stent changes and its patency. There is a discrepancy between diameter of the stent lumen in vitro and after deployment in all patients. Stent occlusion is related to reduction of stent lumen over the time rather than the percent of the stenosis.

Venous stent patency may be affected by collateral vein lumen size.

PURPOSE: Deep venous thrombosis causes blood flow deviation. It is hypothesized that with stent placement, developed collateral veins become redundant. This article evaluates the relation between the surface area of the collaterals and stent patency. METHODS: The azygos and hemiazygos veins were identified and the largest surface area was measured at thoracic level. Patency rates of stented tracts were evaluated and related to collateral vein lumen size. RESULTS: The vena cava occlusion and the azygos and hemiazygos vein surface area measurements were positive and statistically significant related (OR 1.01, 95% CI 1.003-1.019, p = 0.004) respectively (and OR 1.007, 95% CI 1.001-1.013, p = 0.004). An azygos surface area measurement of 23 (p<0.001) and hemiazygos surface area measurement of 40 (p = 0.008) was shown as cut-off point related to higher occlusion rates. CONCLUSIONS: The surface area of major venous collateral pathways seems to be related to stent occlusion in deep venous interventions.

The Effect of Stenting on Venous Hypertension: Results Using a Treadmill Stress Test with Invasive Pressure Measurements in Patients with Iliofemoral Venous Obstruction.

OBJECTIVES: The primary aim was to investigate whether stenting of post-thrombotic iliofemoral obstruction reduces venous hypertension. The secondary aim was to establish whether improvement in haemodynamic parameters impacts on quality of life. METHODS: In this prospective observational study, 12 participants with unilateral post-thrombotic obstruction of the iliac and/or common femoral veins (CFVs) underwent a treadmill stress test with invasive pressure measurements in the CFVs and dorsal foot veins of both affected and non-affected limbs. This was performed the day before and 3 months after stenting the obstructed tract. Paired sample t-tests were used to compare the treatment effect and univariable linear regression analysis to determine the association with improvement in quality of life. RESULTS: Before treatment, CFV pressure increased 34.8 ± 23.1 mmHg during walking in affected limbs compared with 3.9 ± 5.8 mmHg in non-affected limbs. This pressure rise decreased to 22.3 ± 24.8 mmHg after 3 months follow up compared with a 4.0 ± 6.0 mmHg increase in non-affected limbs (-26.2 mmHg difference; 95% CI -41.2 to -11.3). No such effect was found in the dorsal foot veins. The VEINES-QOL increased 25.3 ± 11.3 points after stenting and was significantly associated with a decrease in CFV pressure rise during walking (regression coefficient 0.4; 95% CI 0.1-0.6). CONCLUSION: Stenting of post-thrombotic iliofemoral obstruction significantly reduces venous hypertension in the common femoral vein and correlates with an improvement in the quality of life. Larger studies with a broader range of degree of obstruction need be performed to assess whether pre-stenting pressure measurements can predict post stenting clinical success.

The inability of venous occlusion air plethysmography to identify patients who will benefit from stenting of deep venous obstruction.

Background The aim of this study was to assess whether venous occlusion plethysmography can be used to identify venous obstruction and predict clinical success of stenting. Method Receiver operated characteristic curves were used to determine the ability of venous occlusion plethysmography to discriminate between the presence and absence of obstruction, measured by duplex ultrasound and magnetic resonance venography, and to discriminate between successful and non-successful stenting, measured by VEINES-QOL/Sym. Result Two hundred thirty-seven limbs in 196 patients were included. Areas under the curve for post-thrombotic obstruction were one-second outflow volume 0.71, total venous volume 0.69 and outflow fraction 0.59. Stenting was performed in 45 limbs of 39 patients. Areas under the curve for identifying patients with successful treatment at one year after stenting were 0.57, 0.54 and 0.63, respectively. Conclusion Venous occlusion plethysmography cannot be used to identify venous obstruction proximal to the femoral confluence or to distinguish which patients will benefit from treatment.

The value of hemodynamic measurements by air plethysmography in diagnosing venous obstruction of the lower limb.

OBJECTIVE: Air plethysmography (APG) is a functional, noninvasive test that can assess volumetric changes in the lower limb and might therefore be used as a diagnostic tool in chronic deep venous disease. However, use of APG in chronic deep venous obstructive disease remains debatable. This study assessed the clinical value of APG in identifying chronic deep venous obstruction. METHODS: All patients referred to our tertiary, outpatient clinic between January 2011 and August 2013 with chronic venous complaints and suspected outflow obstruction underwent an outflow fraction (OF), ejection fraction (EF), and residual volume fraction (RVF) test using APG. Duplex ultrasound and magnetic resonance venography were used to establish whether and where obstruction was present. Diagnostic values of these tests were assessed for obstructions at different levels of the deep venous system. RESULTS: A total of 312 limbs in 248 patients were tested. Mean age was 45.5 ± 14.0 years, and 62.5% were female. In post-thrombotic disease, specificity and positive predictive value for OF were as high as 98.4% and 95.0%, respectively; however, sensitivity was 34.8% and negative predictive value was 29.6%, with no clinically relevant positive or negative likelihood ratios. No clinically relevant differences were observed in stratifying for level of obstruction. EF and RVF were as inconclusive. Neither could these parameters be used in diagnosing nonthrombotic iliac vein compression. CONCLUSIONS: We found a poor correlation between OF, EF, or RVF, determined by APG, and the presence of chronic deep venous obstruction. Therefore, use of its relative parameters is unwarranted in daily clinical practice.

A review of a new Dutch guideline for management of recurrent varicose veins.

In 2013, the new Dutch guideline for "Venous Pathology" was published. The guideline was a revision and update from the guideline "Diagnostics and Treatment of Varicose Veins" from 2009 and the guideline "Venous Ulcer" from 2005. A guideline for "Deep Venous Pathology" and one for "Compression Therapy" was added to the overall guideline "Venous Pathology." The chapter about treatment of recurrent varicose veins after initial intervention was recently updated in 2015 and is reviewed here. The Dutch term "recidief varices" or the French "récidive de varices" should be used analogous to the English term "recurrent varicose veins." The DCOP Guideline Development Group Neovarices concluded that "recidief" in Dutch actually suggests recurrence after apparent successful treatment and ignores the natural progression of venous disease in its own right. So the group opted to use the term "neovarices." In the Dutch guideline, neovarices is meant to be an all embracing term for recurrent varicose veins caused by technical or tactical failure, evolvement from residual refluxing veins or natural progression of varicose vein disease at different locations of the treated leg after intervention. This report reviews the most important issues in the treatment of varicose vein recurrence, and discusses conclusions and recommendations of the Dutch Neovarices Guideline Committee.

Clarivein® mechano-chemical ablation an interim analysis of a randomized controlled trial dose-finding study.

OBJECTIVES: The ClariVein® system is an endovenous technique that uses mechano-chemical ablation to treat incompetent truncal veins. This study was conducted to identify the ideal Polidocanol dosage and form for mechano-chemical ablation in order to occlude the great saphenous vein. When adhering to safe dosage levels, sclerosants with higher concentrations potentially limit the extent of treatment. It has been demonstrated that this problem may be overcome by using Polidocanol as a microfoam. This paper was established on findings of a preliminary analysis. MATERIAL AND METHODS: The initial study was a single-blinded multicenter randomized controlled trial where patients are allocated to three treatment arms. Group 1 consisted of mechano-chemical ablation +2% Polidocanol liquid, group 2: mechano-chemical ablation +3% Polidocanol liquid and group 3: mechano-chemical ablation +1% Polidocanol foam RESULTS: Eighty-seven, 34 males and 53 females (60.9%), mean age 55 years s.d. 16.0 (range 24-84), were enrolled in the study. Treatment length was 30 cm (range 10-30) for 95.2% of the patients. Mean operating time was 16 minutes (range 5-70). The mean saphenofemoral junction diameter (7.7 mm) was similar in all three groups. At 6 weeks post-treatment duplex ultrasound showed that 25 out of 25 = 100%, 27 out of 28 = 96.4% and 13 out of 23 = 56.5% were occluded in the mechano-chemical ablation + 2% Polidocanol liquid, mechano-chemical ablation + 3% Polidocanol liquid and mechano-chemical ablation + 1% Polidocanol microfoam respectively (p < 0.001). However, stricter scrutiny showed that the anatomical success rate defined as occlusion of at least 85% of the treated length to be 88.0%, 85.7% and 30.4% respectively (p < 0.001). CONCLUSION: Mechano-chemical ablation using ClariVein® combined with 1% Polidocanol microfoam is significantly less effective and should not be considered as a treatment option of incompetent truncal veins. Further investigation to determine the ideal Polidocanol liquid dosage with mechano-chemical ablation is advocated and is being conducted accordingly.

The effect of distraction on pain perception during an endovenous thermal ablation procedure.

OBJECTIVES: To determine whether audio and visual distraction can affect the pain perception of a patient undergoing endovenous thermal ablation under tumescent anesthesia. METHODS: Patients underwent an endovenous thermal ablation procedure and were randomized into two groups: non-distraction (AVD-) and with distraction (AVD+). Visual analogue scale pain score and hospital anxiety depression scale scores were used to measure outcome. The recruited patients were asked to submit an anticipated visual analogue scale pain score prior to treatment as well as the actual experienced post-operative visual analogue scale pain score. RESULTS: There was no significant difference between the AVD- and AVD+ groups post-operative pain score 2.85 (SD 1.7) versus 2.60 (SD 2.3), p = 0.68. Pain score in women with distraction (AVD+) decreased from 3.81 to 2.42. The pain score in men with distraction (AVD+) increases from 1.88 to 2.82. In the AVD- group, a significant difference was found between men and women (p = 0.014). Disregarding gender, a significant difference was found between the anticipated pain score and the actual pain score in both the AVD- group (p = 0.009) and AVD+ group (p = 0.021). There was a correlation between depression and the pain score, which was not seen between pain and anxiety score. CONCLUSION: The results suggested that audiovisual distraction has no influence on the visual analogue scale pain score during endovenous thermal ablation under tumescent anesthesia. Despite this, patients appreciate and evaluate audio and visual distraction as pleasant to extremely pleasant when applied.

Cyanoacrylate adhesive perforator embolization (CAPE) of incompetent perforating veins of the leg, a feasibility study.

Consideration of treating incompetent perforating veins remains a conundrum based on scientific evidence available till date. While subfascial endoscopic perforator surgery (SEPS) proved to be a worthy alternative for open surgery, other even less invasive techniques were being introduced by the late nineties of the last century. Percutaneous thermo-ablation techniques are still being used today and seem more effective than non-thermal techniques. However, thermal techniques require anaesthesia and potentially may cause inadvertent damage to surrounding tissues such as nerves. Cyanoacrylate adhesive has a proven record, but not for the treatment of chronic venous disease of the leg. Innovation has led to the development of the VenaSeal® Sapheon Closure System which has been designed to use a modified cyanoacrylate glue as a new therapy for truncal vein incompetence. This paper explores the feasibility of ultrasound guided cyanoacrylate adhesive perforator embolization (CAPE). Results show a 76% occlusion rate of incompetent perforating veins without serious complications leading to the conclusion that further investigation with a dedicated delivery device in a larger patient population is warranted.

In vitro evaluation of a new autologous valve-stent for deep venous incompetence.

PURPOSE: To report the results of in vitro hydrostatic bench testing of a new vein-stent combination to correct deep venous incompetence. METHODS: Twelve valves were constructed from a modified Palmaz stent encased in a segment of great saphenous vein harvested from patients during routine varicose vein surgery. An in vitro flow circuit was set up to evaluate opening and closing pressures (in cm H(2)O), and the valve was subsequently subjected to repetitive cycles of increasing prograde flow and reflux pressures. Duplex scanning was used to evaluate valve closure time and detect any possible reflux. RESULTS: The valve mechanism required only 1 to 3 cm H(2)O for opening and 2 to 4 cm H(2)O for closing. Prograde flow of up to 1000 mL/min passed easily through this valve, which remained competent with reflux pressures up to 180 cm H(2)O. Mean valve closure time was 0.15+/-0.07 seconds. Unligated side branches or damage from dissection impaired the competence of 3 valves. CONCLUSION: This new vein-stent valve functions as a normal deep vein valve, requiring only minimal pressures for opening and closing. It allows high flow passage and still remains competent at high reflux pressures. This valve may provide a minimally invasive solution for the correction of deep venous incompetence using autologous material. Further in vivo evaluation will be mandatory.