Black holes in compression therapy: A quest for data.

OBJECTIVE: Although compression therapy (CT) is considered a crucial conservative treatment in chronic venous disease, strong evidence is missing for many clinical indications. This literature review aims to point out what strong evidence we have for CT and all the clinical scenarios where strong evidence still needs to be included. METHODS: The research was conducted on MEDLINE with PubMed, Scopus and Web of Science. The time range was set between January 1980 and October 2022. Only articles in English were included. RESULTS: The main problem with CT is the low scientific quality of many studies on compression. Consequently, we have robust data on the effectiveness of CT only for advanced venous insufficiency (C3-C6), deep vein thrombosis and lymphedema. We have data on the efficacy of compression for venous symptoms control and in sports recovery, but the low quality of studies cannot result in a strong recommendation. For compression in postvenous procedures, superficial venous thrombosis, thromboprophylaxis, post-thrombotic syndrome prevention and treatment, and sports performance, we have either no data or very debated data not allowing any recommendation. CONCLUSIONS: We need high-level scientific studies to assess if CT can be effective or definitely ineffective in the clinical indications where we still have a paucity of or contrasting data.

A comparison of patient-reported outcome measures following technical success and technical failure in the treatment of great saphenous vein incompetence using ClariVein: A subanalysis of a multicenter randomized controlled trial comparing 2% and 3% polidocanol.

OBJECTIVE: This study aimed to compare patient-reported outcomes after technical success (TS) and technical failure (TF) in treating great saphenous vein incompetence (GSV) with ClariVein. METHODS: A subanalysis of a previous trial was conducted on symptomatic GSV incompetence patients who received ClariVein treatment with 2% or 3% polidocanol (POL) and were followed for 6 months. Blinding was implemented for observers and patients, and data from both POL groups were combined. TS was defined as at least 85% occlusion of the treated vein, while TF indicated failure to meet TS criteria. Secondary outcomes included Venous Clinical Severity Score (VCSS), Aberdeen Varicose Vein Questionnaire (AVVQ), and Short-Form 36 Health Survey Questionnaire (SF-36). RESULTS: Among the 364 patients included, the TS rate was 64.5%. Comparison of VCSS, AVVQ, and SF-36 scores between TS and TF groups did not yield significant differences. CONCLUSION: This study indicates no significant variation in VCSS, AVVQ, and SF-36 scores between patients experiencing TS and TF following ClariVein treatment for GSV insufficiency.

Clinical impact of assessing thrombus age using magnetic resonance venography prior to catheter-directed thrombolysis.

OBJECTIVES: Magnetic resonance venography (MRV) is underutilized in the evaluation of thrombus properties prior to endovascular treatment but may improve procedural outcomes. We therefore investigated the clinical impact of using a dedicated MRV scoring system to assess thrombus characteristics prior to endovascular intervention for iliofemoral deep vein thrombosis (DVT). METHODS: This is a post hoc analysis of data from the CAVA trial ( Clinicaltrials.gov :NCT00970619). MRV studies of patients receiving ultrasound-accelerated catheter-directed thrombolysis (CDT) for iliofemoral DVT were reviewed. Thrombus age-related imaging characteristics were scored and translated into an overall score (acute, subacute, or old). MRV scores were compared to patient-reported complaints. MRV-scored groups were compared for CDT duration and success rate. RESULTS: Fifty-six patients (29 men; age 50.8 ± 16.4 years) were included. Using MRV, 27 thrombi were classified acute, 17 subacute, and 12 old. Based on patient-reported complaints, 11 (91.7%) of these old thrombi would have been categorized acute or subacute, and one (3.7%) of the acute thrombi as old. Average duration of CDT to > 90% restored patency differed significantly between groups (p < 0.0001): average duration was 23 h for acute thromboses (range: 19-25), 43 h for subacute (range: 41-62), and 85 h for old thromboses (range: 74-96). CDT was almost eleven times more successful in thromboses characterized as acute and subacute compared to old thromboses (OR: 10.7; 95% CI 2.1-55.5). CONCLUSION: A dedicated MRV scoring system can safely discriminate between acute, subacute, and old thromboses. MRV-based selection is predictive of procedural duration and success rate and can help avoid unnecessary complications. KEY POINTS: • Thrombus age, characterized by MRV as acute, subacute, and old, can predict CDT duration and probability of success. • Accurate pre-interventional MRV-based thrombus aging has the potential to facilitate identification of eligible patients and may thus prevent CDT-related complications.

A multicenter, randomized, dose-finding study of mechanochemical ablation using ClariVein and liquid polidocanol for great saphenous vein incompetence.

BACKGROUND: The purpose of the present study was to identify the ideal polidocanol (POL) concentration for mechanochemical ablation (MOCA) of the great saphenous vein (GSV) using the ClariVein system (Merit Medical, South Jordan, Utah). METHODS: We performed a multicenter, randomized, controlled, single-blind trial with a follow-up period of 6 months. Patients with symptomatic primary truncal GSV incompetence were randomized to MOCA + 2% POL liquid (2% group) or MOCA + 3% POL liquid (3% group). The primary outcome was technical success (TS), defined as an open part of the treated vein segment of ≤10 cm in length. The secondary outcomes were alternative TS, defined as ≥85% occlusion of the treated vein segment, postoperative pain, venous clinical severity scores, Aberdeen varicose vein questionnaire scores, and short-form 36-item health survey questionnaire scores, and complications. RESULTS: From 2012 to 2018, 364 patients (375 limbs) were included, of which, 189 limbs were randomly allocated to the 2% group and 186 to the 3% group. The TS rate at 6 months was 69.8% in the 2% group vs 78.0% in the 3% group (P = .027). A higher overall TS rate was seen in GSVs of ≤5.9 mm compared with GSVs >5.9 mm (84.3% vs 59.5%, respectively; P < .001). The alternative TS rate at 6 months was 61.4% in the 2% group and 67.7% in the 3% group (P = .028). The venous clinical severity scores, Aberdeen varicose vein questionnaire scores, and most short-form 36-item health survey questionnaire domains had improved in both groups (P < .002). Postprocedural pain was low. Two pulmonary embolisms and two deep vein thromboses were seen. Superficial venous thrombosis had occurred more often in the 3% group (18 vs 8 in the 2% group; P = .033). CONCLUSIONS: The results from the present study showed a higher success rate for MOCA with 3% POL liquid than for MOCA with 2% POL liquid at 6 months of follow-up. However, the difference in quality of life was not significant. Long-term follow-up studies are required to investigate whether these results will be sustained in the future.

The relationship between psychological distress and impairment of disease-specific quality-of-life compared between liquid sclerocompression therapy and invasive treatments in patients with superficial venous disease during a one-year follow-up.

INTRODUCTION: Superficial venous disease (SVD) is a very common disease and much research has been done towards finding the ideal treatment and discovering the pathophysiology of SVD. Not much is known about the psychological burden of SVD. Current guidelines and scientific publications tend to focus on clinical and physiological aspects of SVD. The aim of this study was to relate the changes in Quality-of-Life (QoL) after SVD treatment to possible changes in psychological distress (PD). METHODS: A prospective cohort was set up with the assistance of 5 specialized vein clinics in the Netherlands. Inclusion criteria were: 18 years of age or older, fluent in Dutch language, C1 to C6 (CEAP) class intended to be primary treated with either endovenous laser(LA), radiofrequency ablation (RFA) and phlebectomy(PHL) or sclerocompression therapy alone (SCT). Patients were divided in two groups:1. C1-C3 patients treated by SCT2. C1-C6 patients treated invasively (LA, RFA and PHL)Outcomes were a disease specific QoL questionnaire (CIVIQ-20) and a questionnaire to assess PD (Hospital Anxiety and Depression Scales (HADS)). This study was approved by the local institutional review board, following the principles outlines in the Declaration to Helsinki. This trial was registered in the ISRCTN registry with study ID ISRCTN12085308. RESULTS: 442 patients were included in the study and completed the T0 measurements. Mean age of these patients is 54.4 years (s.d. 12.9, 17-90). Number of females: 349 (79.0%), of males: 93 (21.0%). The mean baseline (T-0) HADS depression (0-3) scale scores is 2.54 (s.d. 0.51, n = 412). The mean one-year difference between T-12 HADS depression (0-3) scale scores and baseline T-0 scores is +0.06. The mean baseline (T-0) HADS anxiety (0-3) scale scores is 2.19 (s.d. 0.5, n = 283). The mean one-year difference between T-12 HADS anxiety (0-3) scale scores and baseline T-0 scores is +0.06. Controlled for baseline scores, gender, age, weight and length(BMI), patients in group 2 (receiving invasive treatment) show significantly higher one-year improvement in the QoL of their psychological state of mind than patients in group 1 (receiving SCT and having C1,2,3) (beta 0.158 p = 0.002). CONCLUSIONS: The significant improvement in psychological, QoL and clinical scores that we observe after successful invasive treatment compared to no significant improvement after SCT and the lack of psychological distress in patients with "simple" SVD indicates that SCT is mainly performed for cosmetic reasons. One could thus argue that reimbursement of SCT as a stand-alone medical treatment is debatable.

CAVA (Ultrasound-Accelerated Catheter-Directed Thrombolysis on Preventing Post-Thrombotic Syndrome) Trial: Long-Term Follow-Up Results.

Background The CAVA (Ultrasound-Accelerated Catheter-Directed Thrombolysis Versus Anticoagulation for the Prevention of Post-Thrombotic Syndrome) trial did not show a reduction of post-thrombotic syndrome (PTS) after additional ultrasound-accelerated catheter-directed thrombolysis in patients with acute iliofemoral deep vein thrombosis at 1-year follow-up. This prespecified analysis of the CAVA trial aimed to determine the impact of additional thrombolysis on outcomes of PTS at long-term follow-up. Methods and Results Patients aged 18 to 85 years with a first-time acute iliofemoral deep vein thrombosis were included and randomly assigned (1:1) to either standard treatment plus ultrasound-accelerated catheter-directed thrombolysis or standard treatment alone. The primary outcome was the proportion of PTS (Villalta score ≥5 on 2 occasions ≥3 months apart or venous ulceration) at the final follow-up visit. Additionally, PTS according to the International Society on Thrombosis and Haemostasis (ISTH) consensus definition was assessed to allow external comparability. Major bleedings were the main safety outcome. At a median follow-up of 39.0 months (interquartile range, 23.3-63.8), 120 patients (79.8%) participated in the final follow-up visit: 62 from the intervention group and 58 from the standard treatment group. PTS developed in 19 (30.6%) versus 26 (44.8%) patients, respectively (odds ratio [OR], 0.54; 95% CI, 0.26 to 1.15 [P=0.11]), with an absolute difference between groups of -14.2% (95% CI, -32.0% to 4.8%). Using the ISTH consensus definition, a significant reduction in PTS was observed (29 [46.8%] versus 40 [69.0%]) (OR, 0.40; 95% CI, 0.19-0.84 [P=0.01]) with an absolute difference between groups of -22.2% (95% CI, -39.8% to -2.8%). No new major bleedings occurred following the 12-month follow-up. Conclusions The impact of additional ultrasound-accelerated catheter-directed thrombolysis on the prevention of PTS was found to increase with time. Although this study was limited by its sample size, the overall findings indicate a reduction of mild PTS without impact on quality of life. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT00970619.

Outcome of stenting in central venous obstruction of benign etiology.

Background: The aim of this study is to evaluate long term outcome in patients treated for benign superior vena cava (SVC) syndrome by endovascular techniques. Patients and methods: Between 2015 and 2018, 62 patients suffering from central venous obstruction of benign etiology underwent balloon angioplasty with stent placement for venous obstruction in our department. Patency was assessed clinically, using duplex ultrasound in all patients or with CT-phlebography in selected cases. Results: Median age was 60 years (23-83), forty-one patients (66%) had central venous devices. Swelling of the arm and face were the main symptoms (71%). During the median follow up of 22 months (9-38), cumulative primary patency was 71% after venous stenting. The cumulative assisted primary and the secondary patency were 85% and 92%, respectively. Conclusions: Recanalization and stenting of central vein obstruction has turned out to be the technique of reference and provides satisfactory mid-term patency rates. After adjusting for the risk factors, presence of AV-fistula remained a significant risk factor for recurrent stenosis or loss of patency after intervention.

Association of Successful Ultrasound-Accelerated Catheter-Directed Thrombolysis with Postthrombotic Syndrome: A Post Hoc Analysis of the CAVA Trial.

BACKGROUND: The CAVA trial did not show the anticipated risk reduction for postthrombotic syndrome (PTS) after thrombus removal via additional ultrasound-accelerated catheter-directed thrombolysis (UACDT) in patients with acute iliofemoral deep vein thrombosis (IFDVT). Difficulties in achieving an effective degree of recanalization through thrombolysis may have influenced outcomes. We therefore assessed whether successful UACDT (restored patency ≥ 90%) did reduce the development of PTS. METHODS: This CAVA trial post hoc analysis compared the proportion of PTS at 1-year follow-up between patients with successful UACDT and patients that received standard treatment only. In addition, clinical impact as well as determinants of successful thrombolysis were explored. RESULTS: UACDT was initiated in 77 (50.7%) patients and considered successful in 41 (53.2%, interrater agreement κ = 0.7, 95% confidence interval 0.47-0.83). PTS developed in 15/41 (36.6%) patients in the successful UACDT group versus 33/75 (44.0%) controls (p = 0.44). In this comparison, successful UACDT was associated with lower Venous Clinical Severity Score (3.50 ± 2.57 vs. 4.82 ± 2.74, p = 0.02) and higher EuroQOL-5D (EQ-5D) scores (40.2 ± 36.4 vs. 23.4 ± 34.4, p = 0.01). Compared with unsuccessful UACDT, successful UACDT was associated with a shorter symptom duration at inclusion (p = 0.05), and higher rates of performed adjunctive procedures (p < 0.001) and stent placement (p < 0.001). CONCLUSION: Successful UACDT was not associated with a reduced proportion of PTS 1 year after acute IFDVT compared with patients receiving standard treatment alone. There was, however, a significant reduction in symptom severity and improvement of generic quality of life according to the EQ-5D. Better patient selection and optimization of treatment protocols are needed to assess the full potential of UACDT for the prevention of PTS. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov number, NCT00970619.

Triage of patients with venous and lymphatic diseases during the COVID-19 pandemic - The Venous and Lymphatic Triage and Acuity Scale (VELTAS) : A consensus document of the International Union of Phlebology (UIP), Australasian College of Phlebology (ACP), American Vein and Lymphatic Society (AVLS), American Venous Forum (AVF), European College of Phlebology (ECoP), European Venous Forum (EVF), Interventional Radiology Society of Australasia (IRSA), Latin American Venous Forum, Pan-American Society of Phlebology and Lymphology and the Venous Association of India (VAI) This consensus document has been co-published in Phlebology [DOI: 10.1177/0268355520930884] and Journal of Vascular Surgery: Venous and Lymphatic Disorders [DOI: 10.1016/j.jvsv.2020.05.002]. The publications are identical except for minor stylistic and spelling differences in keeping with each journal's style. The contribution has been published under a Attribution-Non Commercial-No Derivatives 4.0 International (CC BY-NC-ND 4.0), (https://creativecommons.org/licenses/by-nc-nd/4.0/).

The coronavirus disease 2019 (COVID-19) global pandemic has resulted in diversion of healthcare resources to the management of patients infected with SARS-CoV-2 virus. Elective interventions and surgical procedures in most countries have been postponed and operating room resources have been diverted to manage the pandemic. The Venous and Lymphatic Triage and Acuity Scale was developed to provide an international standard to rationalise and harmonise the management of patients with venous and lymphatic disorders or vascular anomalies. Triage urgency was determined based on clinical assessment of urgency with which a patient would require medical treatment or surgical intervention. Clinical conditions were classified into six categories of: (1) venous thromboembolism (VTE), (2) chronic venous disease, (3) vascular anomalies, (4) venous trauma, (5) venous compression and (6) lymphatic disease. Triage urgency was categorised into four groups and individual conditions were allocated to each class of triage. These included (1) medical emergencies (requiring immediate attendance), example massive pulmonary embolism; (2) urgent (to be seen as soon as possible), example deep vein thrombosis; (3) semi-urgent (to be attended to within 30-90 days), example highly symptomatic chronic venous disease, and (4) discretionary/non-urgent- (to be seen within 6-12 months), example chronic lymphoedema. Venous and Lymphatic Triage and Acuity Scale aims to standardise the triage of patients with venous and lymphatic disease or vascular anomalies by providing an international consensus-based classification of clinical categories and triage urgency. The scale may be used during pandemics such as the current COVID-19 crisis but may also be used as a general framework to classify urgency of the listed conditions.

Triage of patients with venous and lymphatic diseases during the COVID-19 pandemic - The Venous and Lymphatic Triage and Acuity Scale (VELTAS):: A consensus document of the International Union of Phlebology (UIP), Australasian College of Phlebology (ACP), American Vein and Lymphatic Society (AVLS), American Venous Forum (AVF), European College of Phlebology (ECoP), European Venous Forum (EVF), Interventional Radiology Society of Australasia (IRSA), Latin American Venous Forum, Pan-American Society of Phlebology and Lymphology and the Venous Association of India (VAI).

The coronavirus disease 2019 (COVID-19) global pandemic has resulted in diversion of healthcare resources to the management of patients infected with SARS-CoV-2 virus. Elective interventions and surgical procedures in most countries have been postponed and operating room resources have been diverted to manage the pandemic. The Venous and Lymphatic Triage and Acuity Scale was developed to provide an international standard to rationalise and harmonise the management of patients with venous and lymphatic disorders or vascular anomalies. Triage urgency was determined based on clinical assessment of urgency with which a patient would require medical treatment or surgical intervention. Clinical conditions were classified into six categories of: (1) venous thromboembolism (VTE), (2) chronic venous disease, (3) vascular anomalies, (4) venous trauma, (5) venous compression and (6) lymphatic disease. Triage urgency was categorised into four groups and individual conditions were allocated to each class of triage. These included (1) medical emergencies (requiring immediate attendance), example massive pulmonary embolism; (2) urgent (to be seen as soon as possible), example deep vein thrombosis; (3) semiurgent (to be attended to within 30-90 days), example highly symptomatic chronic venous disease, and (4) discretionary/nonurgent- (to be seen within 6-12 months), example chronic lymphoedema. Venous and Lymphatic Triage and Acuity Scale aims to standardise the triage of patients with venous and lymphatic disease or vascular anomalies by providing an international consensus-based classification of clinical categories and triage urgency. The scale may be used during pandemics such as the current COVID-19 crisis but may also be used as a general framework to classify urgency of the listed conditions.

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.

Assessing radiation exposure to patients during endovascular treatment of chronic venous obstruction.

BACKGROUND: Post-thrombotic obstruction can be adequately treated by percutaneous transluminal angioplasty and stenting. This procedure is rapidly emerging as a minimally invasive alternative to traditional open surgical operations. However, the patient will be exposed to a significant amount of radiation during preoperative planning and operation. The aim of this study was to evaluate the amount of radiation exposure to patients during venous recanalization. METHODS: All patients undergoing endovenous recanalization from February 2016 to February 2018 were included in this study. The operations were performed in an operating room using a mobile C-arm angiography system. Indirect parameters of cumulative air kerma, kerma-area product, and fluoroscopy time (FT) were recorded concurrently with direct measurements of dose (effective dose [ED]) in the pelvic and neck area using two electronic personal dosimetry devices. The direct measured doses were then correlated with indirect parameters provided by the imaging equipment manufacturers. RESULTS: In total, 78 cases were included in the study. During a median operation time of 154.5 minutes (90-323 minutes), the median FT was 43.7 minutes (15.9-77.7 minutes). Body mass index did not correlate with FT or ED. ED correlated with duration of the intervention (r = 0.59) but better with FT, cumulative air kerma, and kerma-area product (r = 0.76, 0.94, and 1.00, respectively). No patients had evidence of radiation-induced skin injury. CONCLUSIONS: Radiation exposure to patients during endovenous recanalization does not reach the threshold to have a deterministic effect. Indirect parameters of radiation exposure correlated with direct measurements of the ED. Direct dosimetry is likely to be an unnecessary effort for these types of procedures when indirect dose metrics are available.

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.