Post-thrombotic Syndrome In Patients Research Articles

Development and validation of a risk prediction model and prediction tools for post-thrombotic syndrome in patients with lower limb deep vein thrombosis

PurposeOur research aims to compare the predictive performance of decision tree algorithms (DT) and logistic regression analysis (LR) in constructing models, and develop a Post-Thrombotic Syndrome (PTS) risk stratification tool. MethodsWe retrospectively collected and analyzed relevant case information of 618 patients diagnosed with DVT from January 2012 to December 2021 in three different tertiary hospitals in Jiangxi Province as the modeling group. Additionally, we used the case information of 212 patients diagnosed with DVT from January 2022 to January 2023 in two tertiary hospitals in Hubei Province and Guangdong Province as the validation group. We extracted electronic medical record information including general patient data, medical history, laboratory test indicators, and treatment data for analysis. We established DT and LR models and compared their predictive performance using receiver operating characteristic (ROC) curves and confusion matrices. Internal and external validations were conducted. Additionally, we utilized LR to generate nomogram charts, calibration curves, and decision curves analysis (DCA) to assess its predictive accuracy. ResultsBoth DT and LR models indicate that Year, Residence, Cancer, Varicose Vein Operation History, DM, and Chronic VTE are risk factors for PTS occurrence. In internal validation, DT outperforms LR (0.962 vs 0.925, z = 3.379, P < 0.001). However, in external validation, there is no significant difference in the area under the ROC curve between the two models (0.963 vs 0.949, z = 0.412, P = 0.680). The validation results of calibration curves and DCA demonstrate that LR exhibits good predictive accuracy and clinical effectiveness. A web-based calculator software of nomogram (https://sunxiaoxuan.shinyapps.io/dynnomapp/) was utilized to visualize the logistic regression model. ConclusionsThe combination of decision tree and logistic regression models, along with the web-based calculator software of nomogram, can assist healthcare professionals in accurately assessing the risk of PTS occurrence in individual patients with lower limb DVT.

Should we add antiplatelet agents to current deep venous thrombosis treatments? A Cochrane Review summary with commentary.

Venous thromboembolism (VTE) is an important complication in rehabilitation practice despite preventive measures. The management can be complicated because patients may have co-existing cardiovascular comorbidities. To assess the effects of antiplatelet agents in addition to current best medical practice (BMP) compared to current BMP (with or without placebo) for the treatment of deep venous thrombosis (DVT). A summary of the Cochrane Review by Flumignan et al. (2022), with comments from a rehabilitation perspective. The review included six studies with 1625 eligible participants, with data up to 37.2 months of follow-up. When used after standard initial treatment with anticoagulants, antiplatelet agents such as aspirin in addition to BMP, may reduce recurrence of DVT or pulmonary embolism, when compared to BMP plus placebo in a chronic DVT setting and there may be a lower risk for post-thrombotic syndrome in patients with acute DVT. There is no clear difference in side effects, major bleeding, or pulmonary embolism (PE) with the use of antiplatelet agents. Adding antiplatelet agents to standard anticoagulation treatment in patients with VTE could provide benefit without increasing risks in selected patient groups. However, high quality studies with a long-term follow up are needed, including patients in rehabilitation settings.

Incidence and predictors of post-thrombotic syndrome in patients with proximal DVT in a real-world setting: findings from the GARFIELD-VTE registry.

Although substantial progress has been made in the pathophysiology and management of the post-thrombotic syndrome (PTS), several aspects still need clarification. Among them, the incidence and severity of PTS in the real world, the risk factors for its development, the value of patient's self-evaluation, and the ability to identify patients at risk for severe PTS. Eligible participants (n = 1107) with proximal deep-vein thrombosis (DVT) from the global GARFIELD-VTE registry underwent conventional physician's evaluation for PTS 36months after diagnosis of their DVT using the Villalta score. In addition, 856 patients completed a Villalta questionnaire at 24months. Variable selection was performed using stepwise algorithm, and predictors of severe PTS were incorporated into a multivariable risk model. The optimistic adjusted c-index was calculated using bootstrapping techniques. Over 36-months, 27.8% of patients developed incident PTS (mild in 18.7%, moderate in 5.7%, severe in 3.4%). Patients with incident PTS were older, had a lower prevalence of transient risk factors of DVT and a higher prevalence of persistent risk factors of DVT. Self-assessment of overall PTS at 24months showed an agreement of 63.4% with respect to physician's evaluations at 36months. The severe PTS multivariable model provided an optimistic adjusted c-index of 0.68 (95% CI 0.59-0.77). Approximately a quarter of DVT patients experienced PTS over 36months after VTE diagnosis. Patient's self-assessment after 24months provided added value for estimating incident PTS over 36months. Multivariable risk analysis allowed good discrimination for severe PTS.

A systematic review and meta-analysis of risk prediction models for post-thrombotic syndrome in patients with deep vein thrombosis

ObjectiveThis systematic review and meta-analysis aimed to systematically evaluate the prediction models for the risk of post-thrombotic syndrome (PTS) in deep vein thrombosis (DVT) patients. MethodsThis systematic review and meta-analysis was guided by the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). A systematic search on the following electronic database: PubMed/MEDLINE, EMBASE, and Cochrane Library, and Chinese databases such as WANFANG and CNKI was conducted to look for relevant articles based on the research question. The risk of bias for each studies included was carried out based on Prediction Model Risk of Bias Assessment Tool (PROBAST). ResultsWe identified 10 studies that developed a total of 13 clinical prediction models for PTS risk in DVT patients, 3 models were externally validated, 2 models were temporally validated. The top 5 predictors were: BMI (N = 9), Varicose vein (N = 6), Baseline Villalta Score (N = 6), Iliofemoral thrombosis (N = 5), and Age (N = 4). The high risk of bias was from the analysis domain, which the number of participants and selection of predictors often did not meet the requirements of PROBAST. A random-effects meta-analysis of C-statistics was conducted, the pooled discrimination was C-statistic 0.75, 95%CI (0.69, 0.81). ConclusionAmong the 13 PTS risk prediction models reported in this study, no prediction model has been applied to clinical practice due to the lack of external validation. In the development of prediction models, most models were not standardized in data analysis. It is recommended that future studies on the design and implementation of prediction models refer to Transparent reporting of a multivariable prediction model for individual prognosis or diagnosis (TRIPOD) and PROBAST.

Prevalence and Associated Factors of Post-Thrombotic Syndrome in Patients With Deep Vein Thrombosis

Background: Post-thrombotic syndrome (PTS) occurs as a long-term complication of deep vein thrombosis (DVT). The aim of this study was to evaluate the prevalence of PTS and its associated factors in a cohort of patients with lower extremity DVT in Sri Lanka. Methods: A descriptive cross-sectional study was conducted in 80 patients who were assessed 6 months to 2 years after the acute episode of DVT. They were assessed using Vilalta scale to diagnose and grade the severity of PTS, anthropometry to calculate body mass index (BMI), duplex ultrasound scans, patients’ clinic record including international normalized ratio (INR) charts and an interviewer administered questionnaire. Categorical data were analyzed using Chi-square test and continuous variables were analyzed using analysis of variance (ANOVA) to determine association. Results: Prevalence of PTS was 45.5% (36/80) according to Villalta scale. Recurrent DVT (P = 0.0002), high BMI (P = 0.073), and previous venous in competence (P = 0.032), showed significant association with PTS. Proximal DVT demonstrated a strong association with PTS (P = 0.002). Residual thrombosis at 3 months was strongly associated with PTS (P &lt; 0.001), however, with a bias of very low sample with repeat duplex at 3 months post event. Awareness of PTS was extremely low (n = 0, 0%). Practice of elastic compression stockings (ECSs) use as a preventative measure of PTS failed to show any significant association (P = 0.61). Conclusions: This study showed a significant prevalence of PTS among patients with previous DVT. Development of PTS is probably multi factorial. A validated risk assessment tool should be used to identify at-risk patients as prevention is the best approach to this irreversible morbidity. J Curr Surg. 2022;12(2):38-44 doi: https://doi.org/10.14740/jcs459

Criteria to predict midterm outcome after stenting of chronic iliac vein obstructions (PROMISE trial)

BackgroundEndovenous stent placement has become a first-line approach to prevent post-thrombotic syndrome in patients with chronic post-thrombotic obstruction (PTO) or nonthrombotic iliac vein lesions if conservative management fails. This study aims to identify factors associated with loss of patency to facilitate patient selection for endovenous stenting. MethodsWe retrospectively analyzed 108 consecutive patients after successful endovenous stenting for chronic vein obstruction performed at a single institution from January 2008 to July 2020. Using multivariable logistic regression, we explored potential predictive factors for loss of stent patency, including baseline demographics, post-thrombotic changes, and peak flow velocities measured in the common femoral vein (CFV), deep femoral vein, and femoral vein (FV) using duplex ultrasound examination. ResultsThe mean follow-up duration was 41 ± 26 months, and participants had a mean age of 47.4 ± 15.4 years with 46.3% women. Ninety (83.3%) patients had PTO and 18 (16.7%) had nonthrombotic iliac vein lesions, predominantly due to May-Thurner syndrome. Loss of patency occurred in 20 (18.5%) patients, all treated for PTO. Comorbidities, side of intervention, and sex did not differ between patients with occluded and patent stents. Stent occlusion was more common with increasing number of stents implanted (P < .001) and with distal stent extension into and beyond the CFV (P < .001). Preinterventional predictive factors for stent occlusion were lower duplex ultrasound peak velocity in the CFV (odds ratio [OR]: 7.52, 95% confidence interval [CI]: 2.54-22.28; P < .001) and FV (OR: 10.75, 95% CI: 2.07-55.82; P < .005), and post-thrombotic changes in the deep femoral vein (OR: 4.51, 95% CI: 1.53-13.25; P = .006) and FV (OR: 3.62: 95% CI: 1.11-11.84; P = .033). Peak velocities of ≤7 cm/s (interquartile range: 0-20 cm/s) in the CVF and ≤8 cm/s (interquartile range: 5-10 cm/s) in the FV were significantly associated with loss of patency. ConclusionsInsufficient venous inflow as assessed by low peak velocities in the CFV and FV as well as post-thrombotic findings represent reliable risk predictors for stent occlusions, warranting their inclusion into the decision-making process for invasive treatment of PTO.

The Effect of Balloon-Assisted Pharmacomechanical Catheter-Directed Thrombolysis on the Patency and Post-Thrombotic Syndrome in Patients with Acute Iliofemoral Deep Vein Thrombosis: Is it Really Necessary or Not?

The objective of this study was to describe the contribution and advantage of balloon-dilatation of iliac and femoral veins following pharmacomechanical catheter-directed thrombolysis (PCDT) on the development of post-thrombotic syndrome (PTS). From October 2018 and January 2022, 85 patients with acute total occlusion of the iliac and femoral veins were treated with PCDT. The cohort was divided into 2 groups depending on the utilization of concomitant balloon dilatation of iliac and femoral veins (Group 1, n=34, 40.0%) or not (Group 2, n=51, 60.0%) during the PCDT. All patients underwent duplex ultrasound scanning for evaluating the patency of iliac veins and recanalization rates at 3, 6, and 12months postoperatively. The Villalta score was used to score the severity of PTS at 12months postoperatively. Patients who underwent balloon-assisted PCDT (group 1) exhibited significantly higher primary patency rates in common iliac vein (CIV) (recanalization 84.3±14.6%, P=0.003), external iliac vein (EIV) (recanalization 82.8±17.2, P=0.003) and common femoral vein (CFV) (recanalization 88.1±12.1%, P=0.038) compared with the group 2 at the end of 12months follow-up. Only 2 patients underwent venous stenting in follow-up due to severe venous claudication, however, 13 patients were required iliac vein stenting due to severe PTS proved with a high Villalta score at 12-month follow-up. The d-dimer level at 1-year follow-up had also significantly lower in Group 1 due to higher rates of patency and lower thrombosis burden. The most common bleeding events were hematuria (n=4) or oozing in the puncture site (n=4). This study showed that balloon-assisted PCDT reduces the risk of PTS, is more successful in common iliac vein recanalization, reduces the need for the venous stent, and even lowers the D-dimer levels of the patients compared to routine PCDT alone.

Abstract No. 155 Single-procedure, 8Fr rheolytic pharmacomechanical iliofemoral deep venous thrombectomy: a retrospective study of efficacy, safety and durability

A multicenter randomized controlled trial demonstrated reduction in severity of post-thrombotic syndrome in patients with symptomatic iliofemoral deep vein thrombosis (DVT) following pharmacomechanical thrombectomy/thrombolysis. However, patients in this trial were treated with variable lysis durations, including overnight lytic infusion. Further, the primary thrombectomy device used consisted of a 6Fr rheolytic thrombectomy catheter. Since then, an 8Fr rheolytic system has been developed specifically for deep venous disease, which may improve procedural efficiency and obviate the need for overnight lytic infusion.

Risk Factors for Post-Thrombotic Syndrome in Patients With a First Proximal Deep Venous Thrombosis Treated With Direct Oral Anticoagulants.

The incidence of post-thrombotic syndrome (PTS) in patients with deep vein thrombosis (DVT) treated with direct oral anticoagulants (DOACs) remains a matter of debate. Hence, our endeavor to investigate a large cohort of patients with a first episode of proximal DVT treated with DOACs to ascertain the incidence and predisposing risk factors for PTS. All consecutive patients referred to the Thrombotic and Haemorrhagic Diseases Unit of Padova University Hospital (Italy) between January 2014 and January 2018 for a first episode of proximal DVT were considered for enrollment. Participants received DOACs for a minimum period of 3months. PTS was assessed using the Villalta score up to 36months after DVT diagnosis. Among 769 enrolled patients (M/F 353/416, age range 26-87years), 152 (19.8%) developed PTS and 30 (3.9%) developed severe PTS. The adjusted hazard ratio was significant for obesity (1.64, 95% CI 1.28-2.39) and DVT site (femoral and/or iliac veins vs popliteal vein) (1.23, 95% CI 1.15-3.00). The incidence of PTS is not negligible in patients with proximal DVT despite the use of DOACs. We identified obesity and iliofemoral DVT as possible risk factors for PTS. Larger prospective studies are needed to confirm our findings and optimize therapeutic strategies.

Associated factors of postthrombotic syndrome in patients with deep vein thrombosis

Associated factors of postthrombotic syndrome in patients with deep vein thrombosis

Elastic compression stockings for prevention of the post-thrombotic syndrome in patients with and without residual vein thrombosis and/or popliteal valve reflux.

Not available.

Medium-term outcomes after inferior vena cava reconstruction for acute and chronic deep vein thrombosis and retroperitoneal fibrosis

ObjectiveIn the present study, we evaluated the technical and clinical outcomes after endovascular inferior vena cava (IVC) reconstruction in patients with nonmalignant obstruction. MethodsThe preoperative, procedural, and follow-up medical records and imaging studies were retrospectively reviewed for 59 consecutive patients who had undergone endovascular IVC reconstruction for nonmalignant obstruction from February 2014 to January 2019. The patients were classified into three groups according to the quality of their infrainguinal inflow vessels. The outcomes measured were the primary, primary-assisted, and secondary patency rates, reintervention rates, and symptomatic resolution. ResultsThe indications for treatment were post-thrombotic syndrome (n = 41), acute deep vein thrombosis (n = 12), and retroperitoneal fibrosis (n = 6). The median patient age was 37 years, 11 months, 71.2% were men, and 32.2% had a diagnosis of thrombophilia, with no significant difference in these demographics between the three inflow groups. The median follow-up duration was 2 years, 3 months (range, 6 months to 6 years, 5 months). The whole-cohort primary patency was 91.2%, 71.0%, and 24.1% at 1, 3, and 5 years, respectively. Secondary patency was 76.7% at 1 year and 66.4% at both 3 and 5 years. Inflow group A (no post-thrombotic disease in the femoral or deep femoral veins) demonstrated significantly higher primary patency compared with group B (stenotic disease in one or two infrainguinal inflow veins; P = .009) and significantly higher secondary patency than for both groups B (P = .008) and C (all three infrainguinal inflow veins had stenosed or femoral and/or deep femoral vein occlusion was present; P = .04). In post-thrombotic syndrome patients, the Villalta scores had decreased from a mean of 14.2 to 8.1 at 1 year and 6.8 at 2 years, and the Venous Insufficiency Epidemiological and Economic Study Quality of Life score had improved from a mean of 19.8 to 54.1 and 57.3 at 1 and 2 years, respectively. In the patients with acute deep vein thrombosis, the Villalta score was 2.8 at 1 year and 0 at 2 years. In the patients with retroperitoneal fibrosis, the Venous Insufficiency Epidemiological and Economic Study Quality of Life score had improved from a mean of 25.3 at baseline to 44 at 6 months. ConclusionsEndovascular IVC reconstruction for nonmalignant obstruction can achieve good patency and clinical improvement, although the outcomes were poorer for patients with post-thrombotic disease of the femoral and deep femoral veins.

Clinical outcomes of venous self-expanding stent placement for iliofemoral venous outflow obstruction

ObjectiveIn the present study, we evaluated the feasibility of a self-expanding venous stent for treating iliofemoral venous obstruction. MethodsThe present retrospective study reviewed the data from 49 patients who had undergone Zilver Vena (Cook Medical, Bloomington, Ind) stent placement for treatment of iliofemoral venous obstruction from September 2017 to March 2019. All patients had undergone received follow-up duplex ultrasound examinations to assess for stent patency. The Villalta scores and Venous Clinical Severity Scores (VCSSs) were also calculated to stratify the postoperative improvement in disease. ResultsOf the 49 patients, 19 had had acute deep vein thrombosis, 7, nonthrombotic iliac venous lesions, and 23, post-thrombotic syndrome. At 1 year after Zilver Vena stent placement, the primary, assisted primary, and secondary patency rates were 93.8%, 95.9%, and 97.9%, respectively. The baseline median Villalta score before treatment for those with post-thrombotic syndrome was 19 (range, 11-30), and the median VCSS for the patients with post-thrombotic syndrome and nonthrombotic iliac venous lesions was 11 (range, 6-25). At 1 year after stent placement, the median Villalta score for the post-thrombotic syndrome patients was 4.0 (range, 2-18), and the median VCSS for the post-thrombotic syndrome and nonthrombotic iliac venous lesions patients was 3.0 (range, 2-12). ConclusionsVenous placement of self-expanding stents offers excellent 1-year patency rates and improved the outcomes of patients with iliofemoral venous obstruction caused by acute deep vein thrombosis, nonthrombotic iliac venous lesions, and post-thrombotic syndrome.

Time-Restricted Salutary Effects of Blood Flow Restoration on Venous Thrombosis and Vein Wall Injury in Mouse and Human Subjects.

Up to 50% of patients with proximal deep vein thrombosis (DVT) will develop the postthrombotic syndrome characterized by limb swelling and discomfort, hyperpigmentation, skin ulcers, and impaired quality of life. Although catheter-based interventions enabling the restoration of blood flow (RBF) have demonstrated little benefit on postthrombotic syndrome, the impact on the acuity of the thrombus and mechanisms underlying this finding remain obscure. In experimental and clinical studies, we examined whether RBF has a restricted time window for improving DVT resolution. First, experimental stasis DVT was generated in C57/BL6 mice (n=291) by inferior vena cava ligation. To promote RBF, mice underwent mechanical deligation with or without intravenous recombinant tissue plasminogen activator administered 2 days after deligation. RBF was assessed over time by ultrasonography and intravital microscopy. Resected thrombosed inferior vena cava specimens underwent thrombus and vein wall histological and gene expression assays. Next, in a clinical study, we conducted a post hoc analysis of the ATTRACT (Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis) pharmacomechanical catheter-directed thrombolysis (PCDT) trial (NCT00790335) to assess the effects of PCDT on Venous Insufficiency Epidemiological and Economic Study quality-of-life and Villalta scores for specific symptom-onset-to-randomization timeframes. Mice that developed RBF by day 4, but not later, exhibited reduced day 8 thrombus burden parameters and reduced day 8 vein wall fibrosis and inflammation, compared with controls. In mice without RBF, recombinant tissue plasminogen activator administered at day 4, but not later, reduced day 8 thrombus burden and vein wall fibrosis. It is notable that, in mice already exhibiting RBF by day 4, recombinant tissue plasminogen activator administration did not further reduce thrombus burden or vein wall fibrosis. In the ATTRACT trial, patients receiving PCDT in an intermediate symptom-onset-to-randomization timeframe of 4 to 8 days demonstrated maximal benefits in Venous Insufficiency Epidemiological and Economic Study quality-of-life and Villalta scores (between-group difference=8.41 and 1.68, respectively, P<0.001 versus patients not receiving PCDT). PCDT did not improve postthrombotic syndrome scores for patients having a symptom-onset-to-randomization time of <4 days or >8 days. Taken together, these data illustrate that, within a restricted therapeutic window, RBF improves DVT resolution, and PCDT may improve clinical outcomes. Further studies are warranted to examine the value of time-restricted RBF strategies to reduce postthrombotic syndrome in patients with DVT.

Management of inferior vena cava thrombosis with the FlowTriever and ClotTriever systems

ObjectiveAlthough inferior vena cava (IVC) thrombosis is infrequently encountered, it carries a significant risk of post-thrombotic syndrome and pulmonary embolus. Recent studies show no difference in the incidence of post-thrombotic syndrome in patients with iliofemoral deep venous thrombosis (DVT) treated with pharmacothrombolysis vs anticoagulation alone; however, there is an associated increased risk of bleeding. The treatment of IVC thrombosis is less well-studied and the hemodynamic changes may be more significant with pharmacothrombolysis, although the bleeding risk remains. The ClotTriever and FlowTriever systems remove thrombus from veins without the use of thrombolytics. Our study evaluates outcomes of patients undergoing mechanical thrombectomy for the treatment of IVC thrombosis using the ClotTriever and FlowTriever devices. MethodsA retrospective chart review was performed to identify consecutive patients who underwent mechanical thrombectomy for the treatment of IVC thrombosis using the ClotTriever and/or FlowTriever systems from November 2018 to January 2020 at four data-sharing institutions. The decision of which device(s) to use was at the discretion of the surgeon. Patient demographics, symptomatology, and imaging characteristics were captured at presentation and follow-up. ResultsA total of 15 patients met the inclusion criteria; 10 were male, and the average age was 59 years. The majority of patients were symptomatic at presentation (n = 14), had a prior history of DVT (n = 13), and had a preexisting IVC filter (n = 8). Eleven patients presented with acute onset (<1 week) of symptoms, whereas three patients had subacute (1-4 weeks) symptoms. Most patients had an associated iliofemoral DVT (n = 13) and were treated with both ClotTriever and FlowTriever (n = 8); others were treated with either ClotTriever or FlowTriever alone (n = 5 and n = 2, respectively). Technical success was achieved in all but two patients, one who had a nonocclusive thrombus densely adherent to a preexisting IVC filter and another who had a chronic rubbery clot in the IVC that could not be cleared. No patient required concomitant lytic therapy or a postoperative stay in the intensive care unit. Furthermore, there were no postoperative bleeding events, myocardial infarctions, pulmonary emboli, renal impairments, or deaths. The median length of stay was 3 days (range, 1-37 days). Patients underwent postoperative follow-up (n = 7) as well as extended follow-up (>6 months; n = 8). All patients who achieved technical success were asymptomatic without evidence of reocclusion of the IVC on follow-up imaging. ConclusionsIn our multicenter series of 15 patients, The ClotTriever and FlowTriever showed promise in the treatment of IVC thrombosis without the use of fibrinolytic drugs, with no bleeding events and no requirement for intensive care unit stay.

A CASE OF PHLEGMASIA CERULEA DOLENS AND MAY-THURNER SYNDROME IN A YOUNG MALE WITH TRIPLE-POSITIVE ANTIPHOSPHOLIPID ANTIBODY SYNDROME

SESSION TITLE: Medical Student/Resident Critical Care Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Phlegmasia cerulea dolens (PCD) is an uncommon form of deep vein thrombosis (DVT) typically presenting with acute limb swelling, pain, and cyanosis. Diagnosis of PCD should be made promptly as these patients may develop limb-threatening complications such as gangrene and compartment syndrome. We describe a young male presenting with his first episode of provoked venous thromboembolism (VTE) as PCD complicated with May-Thurner syndrome (MTS) and Antiphospholipid antibody syndrome (APS). CASE PRESENTATION: A 37-year-old obese male with type 2 diabetes, hypertension, and hyperlipidemia was directly admitted to the medicine floor with extensive left lower extremity DVT (including ileofemoral vein thrombosis) found on outpatient duplex ultrasonography. At initial hospitalization, he was tachycardic but without respiratory distress or hemodynamic instability. His left lower extremity was tender and edematous with cyanosis. Diagnosis of PCD was made and patient was treated with subcutaneous enoxaparin. He received catheter-directed thrombolysis for PCD with alteplase and heparin infusion. During left leg venogram, he was discovered to have MTS, and subsequently underwent stent placement of left common iliac vein, external iliac vein, and common femoral vein. After stent placement, patient received bridging to warfarin with enoxaparin and was discharged home two days later. Patient’s family history was significant for Systemic Lupus Erythematosus. During hospitalization, his antibody testing revealed positivity for anti-cardiolipin, anti-beta-2 glycoprotein antibodies in addition to positive functional lupus anticoagulant assay. Positivity confirmed with repeat testing of anti-cardiolipin antibodies and lupus anticoagulant assay at 15 weeks after hospitalization - confirming the diagnosis of triple-positive APS. DISCUSSION: Treatment of PCD is anticoagulation therapy with adjunctive catheter-directed thrombolysis. Outcomes comparing additional catheter-directed thrombolysis versus anticoagulation alone have shown that combination treatment reduces the incidence of post-thrombotic syndrome in patients with acute iliofemoral DVT. Recognition of DVT associated with MTS is important as treatment includes stent placement to maintain venous outflow. Recognition of triple-positive APS is an indication for extended anticoagulation as this portends a high risk of recurrent VTE. Patient was discharged with warfarin therapy because the use of direct oral anticoagulation in patients with APS remains controversial. Recent studies showed increased risk of recurrent thrombosis, particularly in patients with APS who are triple-positive. CONCLUSIONS: We reported a case, 37 year old male with phlegmasia cerulea dolens and May-Thurner syndrome resulting from triple-positive antiphospholipid antibody syndrome. Reference #1: Casey ET, Murad MH, Zumaeta-garcia M, et al. Treatment of acute iliofemoral deep vein thrombosis. J Vasc Surg. 2012;55(5):1463-73 Reference #2: Haig Y, Enden T, Grøtta O, et al. Post-thrombotic syndrome after catheter-directed thrombolysis for deep vein thrombosis (CaVenT): 5-year follow-up results of an open-label, randomised controlled trial. Lancet Haematol. 2016;3(2):e64-71 Reference #3: Dufrost V, Risse J, Reshetnyak T, et al. Increased risk of thrombosis in antiphospholipid syndrome patients treated with direct oral anticoagulants. Results from an international patient-level data meta-analysis. Autoimmun Rev. 2018;17(10):1011-1021 DISCLOSURES: No relevant relationships by Waqas Adeel, source=Web Response No relevant relationships by Robert Decker, source=Admin input No relevant relationships by Shuisen Li, source=Web Response No relevant relationships by Preysi Patel, source=Web Response No relevant relationships by Chun Siu, source=Web Response

Factors associated with the development of post-thrombotic syndrome in patients with iliofemoral deep venous thrombosis who underwent catheter-directed thrombolysis.

To identify predictors of post-thrombotic syndrome in patients with iliofemoral deep venous thrombosis who underwent catheter-directed thrombolysis. Fifty-two consecutive patients who underwent catheter-directed thrombolysis were included in this retrospective study. In addition to catheter-directed thrombolysis, aspiration thrombectomy or stent placement was performed if needed. At six months, duplex ultrasound was performed to assess iliofemoral patency and deep venous reflux. Post-thrombotic syndrome was assessed using the clinical, etiologic, anatomic, and pathophysiologic classification (post-thrombotic syndrome present ≥3 on a scale from 0 to 6). Univariate analysis and multivariate logistic regression were used to identify predictors of post-thrombotic syndrome. Median follow-up was 52 months and post-thrombotic syndrome developed in nine patients (17.3%). In univariate analysis, stent placement (odds ratio 0.16, p = 0.022) was negatively associated with post-thrombotic syndrome, whereas iliofemoral venous obstruction with reflux at six months (OR 6.08, p = 0.037) was positively associated with post-thrombotic syndrome. Multivariate analysis indicated that stent placement was associated with reduced risk of post-thrombotic syndrome (OR 0.17, p = 0.043), and iliofemoral obstruction with reflux was associated with increased risk (OR 6.67, p = 0.046). Stent placement and iliofemoral venous obstruction with reflux, respectively, were important protective and risk factors for post-thrombotic syndrome in patients who underwent catheter-directed thrombolysis.

Biases of Villalta scale in classifying post-thrombotic syndrome in patients with pre-existing chronic venous disease

ObjectiveThe Villalta scale (VS) is a recommended and widely used clinical severity score for diagnosis and grading of post-thrombotic syndrome (PTS). However, patients with primary chronic venous disease (CVD) who have a history of deep venous thrombosis (DVT) may be classified as having PTS even though post-thrombotic disease is not actually present. The purpose of this study was to investigate the biases of the VS with use in patients with pre-existing CVD. MethodsThis single-center, prospective, observational study included patients who were diagnosed with CVD during a 12-month period from 2016 to 2017. The VS and the Venous Clinical Severity Score (VCSS) were completed, and bilateral lower extremity venous duplex ultrasound studies were performed. The correlation of the VS with the VCSS was analyzed. Sensitivity, specificity, positive bias, and negative bias of the VS combined with a history of DVT were calculated. For patients in whom DVT developed during the study, the VS score was taken 12 months after the onset of DVT and compared with the score before DVT. ResultsA total of 288 patients were included. The VS score correlated well with the VCSS, with a correlation coefficient of 0.86 (P < .001). The two scores changed similarly over time. The accuracy of the VS combined with a history of DVT was 94.1%, with a sensitivity of 71.4% and a specificity of 95.9%. The positive bias was as high as 42.3%, although the negative bias was 2.3%. The VS score decreased to a normal level during follow-up in 41.7% of the CVD patients in whom a new DVT developed (n = 12). ConclusionsThe use of the VS for defining PTS appeared to misclassify those with primary CVD and a history of DVT as having PTS by 42.3%. Using the VS at follow-up in patients with PTS and pre-existing CVD may be misleading. Re-evaluation of the results of previous studies that used the VS may be needed.

3:18 PM Abstract No. 84 Iliac and femoral vein occlusive disease treated with a self-expanding venous stent: 24-month results from the prospective, multicenter VERNACULAR trial

To assess the performance of a self-expanding stent specifically designed for veins (VENOVO Venous Stent) for the treatment of iliac and femoral vein occlusions. The VERNACULAR study was conducted at 22 centers in the United States, Europe, and Australia. The intent-to-treat population included 170 patents, 93 postthrombotic syndrome patients (PTS) and 77 non-thrombotic iliac vein lesion patients (NIVL). Primary endpoints were major adverse events (MAEs) through 30 days and 12-month primary patency, defined as freedom from target vessel revascularization and freedom from thrombotic occlusion and duplex-ultrasound derived stenosis >50%. Secondary outcomes included primary patency, the Venous Clinical Severity Score (VCSS) Pain Assessment, Quality of Life (CIVIQ-20), and target lesion revascularization (TLR) at 24 months. Radiographs were assessed for stent fracture by the venographic core laboratory. Freedom from MAEs through 30 days was 93.5%, non-inferior to a performance goal (PG) of 89% (P = 0.032) while primary patency at 12 months was 88.3%, superior to a PG of 74% derived from the venous stent literature (P < 0.0001). Follow-up at two years was 86.4% (147/170 patients). Primary patency at 24 months was 83.2% (90% CI 77.3%, 89.1%); 77.3% for the PTS subgroup and 95.2% for the NIVL patients. Primary patency estimated by Kaplan-Meier survival analysis was 84.3% for the ITT group at 760 days. The 24-month TLR rate was 10.9% resulting in a freedom from TLR of 89.4% (95% CI 83.6%, 93.7%). The mean VCSS Pain Score improved from 0.6 at 12 months to 0.4 (95% CI: 0.46, 0.74) at 24-months with an overall improvement from baseline of 1.9 (median, 2.0); CIVIQ-20 scores at two years also improved (15.6 points) from baseline values. No stent fractures were observed at 12 or 24 months. Observations from the VERNACULAR trial at two years supported the 12-month results. The VENOVO stent could be deployed successfully in obstructive iliofemoral vein lesions. Primary patency was 88.3% at 12 months and 83.2% at 24 months. Reintervention rates were low, with no stent fractures reported through two years.

CRT-200.01 24-Month Results From the Prospective, Multicenter VERNACULAR Trial for the Treatment of Iliac and Femoral Vein Occlusive Disease With the Venovo Self-expanding Venous Stent

To assess the performance and safety of a dedicated venous stent (Venovo Venous Stent, Becton Dickinson) for the treatment of iliofemoral vein occlusive disease. 170 patients were enrolled in the intent-to-treat population, 93 post-thrombotic syndrome patients (PTS) and 77 non-thrombotic iliac vein