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.

Stent extension into a single inflow vessel is a valuable option after endophlebectomy.

Background Venous stenting with an endophlebectomy and arteriovenous fistula can be performed in patients with extensive post-thrombotic changes. However, these hybrid procedures can induce restenosis, sometimes requiring stent extension, into a single inflow vessel. This study investigates the effectiveness of stenting into a single inflow vessel. Methods All evaluated patients had temporary balloon occlusion of the arteriovenous fistula to evaluate venous flow into the stents. When stent inflow was deemed insufficient, AVF closure was postponed and additional stenting was performed. Patency rates and clinical outcomes were evaluated. Results Twenty-four (38%) of 64 patients had additional stenting. The primary, assisted primary and secondary patency were 60 %, 70% and 70% respectively. Villalta score reduced by 6.1 points ( p < 0.001), and venous clinical severity score by 2.7 points ( p = 0.034). Conclusion Stenting through the femoral confluence into a single inflow vessel is a feasible bailout option if primary hybrid intervention fails with relative high patency rates and clinical improvement.

A randomised controlled trial comparing venous stenting with conservative treatment in patients with deep venous obstruction: research protocol.

INTRODUCTION: Deep venous obstruction (DVO) has a great impact on quality of life (QoL) comparable to angina pectoris or chronic pulmonary disease. Post-thrombotic scar formation and May-Thurner syndrome (MTS) are the most common causes of DVO. Conventional treatment of DVO focuses on reducing pain or leg swelling by use of (pain) medication and therapeutic elastic stockings. In the past, a venous bypass was offered in severe post-thrombotic cases, but this procedure showed bad clinical and patency outcomes. With the introduction of percutaneous angioplasty and dedicated venous stents new opportunities were created. Deep venous stenting has been shown to be effective in retrospective case series. However, there is no prior research in which QoL after interventional treatment is compared with QoL after conventional treatment. Currently, there is a debate about the true additional value of interventional treatment. We investigate whether those patients who are treated with stenting experience a change in short form 36 (SF-36) and the Veines-QoL/Sym questionnaires compared with conventionally treated patients. METHODS AND ANALYSIS: This is a randomised trial comparing conservative deep venous management to interventional treatment. A total of 130 patients with post-thrombotic syndrome (PTS) or MTS, eligible for interventional percutaneous treatment, who did not have previous deep venous intervention will be included. Patients will be randomised to conservative treatment or venous stenting and stratified for the PTS or MTS subgroup. Conservative treatment consists of either one or a combination of pain medications, manual lymphatic drainage, compression stockings and regular post-thrombotic anticoagulant therapy.The primary outcome is the QoL change after 12 months compared with baseline QoL. Secondary outcomes are QoL changes at 6 weeks, clinical assessment of DVO, recurrence rate of deep venous thrombosis at 6 weeks and 12 months, and the total amount of working days lost. Intervention-specific outcomes include complications and patency. ETHICS AND DISSEMINATION: The protocol is approved by the Medical Ethics Committee of Academisch ziekenhuis Maastricht/Universiteit Maastricht, The Netherlands (protocol number NLNL55641.068.15 / METC 161008).We aim to publish the results of this study in a peer reviewed journal and present our findings at national or international conferences. TRIAL REGISTRATION NUMBER: The study protocol was registered at www.clinicaltrials.gov (registration number: NCT03026049) on 17 January 2017.

Prediction of venous wound healing with laser speckle imaging.

Introduction Laser speckle imaging is used for noninvasive assessment of blood flow of cutaneous wounds. The aim of this study was to assess if laser speckle imaging can be used as a predictor of venous ulcer healing. Methods After generating the flux speckle images, three regions of interest (ROI) were identified to measure the flow. Sensitivity, specificity, negative predictive value, and positive predictive value for ulcer healing were calculated. Results In total, 17 limbs were included. A sensitivity of 92.3%, specificity of 75.0%, PPV of 80.0%, and NPV 75.0% were found in predicting wound healing based on laser speckle images. Mean flux values were lowest in the center (ROI I) and showed an increase at the wound edge (ROI II, p = 0.03). Conclusion Laser speckle imaging shows acceptable sensitivity and specificity rates in predicting venous ulcer healing. The wound edge proved to be the best probability for the prediction of wound healing.