Catheter-Directed Thrombolysis Protocols for Deep Venous Thrombosis of the Lower Extremities-A Systematic Review and Meta-analysis.

OBJECTIVE: To summarize characteristics, complications, and success rates of different catheter-directed thrombolysis (CDT) protocols for the treatment of lower extremity deep venous thrombosis (LE-DVT). METHODS: A systematic review using electronic databases (MEDLINE, Scopus, and Web of Science) was performed to identify randomized controlled trials and observational studies related to LE-DVT treated with CDT. A random-effects model meta-analysis was performed to obtain the pooled proportions of early complications, postthrombotic syndrome (PTS), and venous patency. RESULTS: Forty-six studies met the inclusion criteria reporting 49 protocols (n = 3,028 participants). In studies that addressed the thrombus location (n = 37), LE-DVT had iliofemoral involvement in 90 ± 23% of the cases. Only four series described CDT as the sole intervention for LE-DVT, while 47% received additional thrombectomy (manual, surgical, aspiration, or pharmacomechanical), and 89% used stenting.Definition of venogram success was highly variable, being the Venous Registry Index the most used method (n = 19). Among those, the minimal thrombolysis rate (<50% lysed thrombus) was 0 to 53%, partial thrombolysis (50-90% lysis) was 10 to 71%, and complete thrombolysis (90-100%) was 0 to 88%. Pooled outcomes were 8.7% (95% confidence interval [CI]: 6.6-10.7) for minor bleeding, 1.2% (95% CI: 0.8-1.7%) for major bleeding, 1.1% (95% CI: 0.6-1.6) for pulmonary embolism, and 0.6% (95% CI: 0.3-0.9) for death. Pooled incidences of PTS and of venous patency at up to 1 year of follow-up were 17.6% (95% CI: 11.8-23.4) and 77.5% (95% CI: 68.1-86.9), respectively. CONCLUSION: Assessment of the evidence is hampered by the heterogeneity of protocols, which may be reflected in the variation of PTS rates. Despite this, CDT is a low-risk treatment for LE-DVT.

[Pelvic vein thrombosis : Current treatment options and importance of recanalization procedures]. / Beckenvenenthrombose : Aktuelle Therapieoptionen und Stellenwert rekanalisierender Verfahren.

Venous thrombosis is a frequent disorder. A distinction is made between an acute phase of the disease and a chronic manifestation, the postthrombotic syndrome. In particular, proximal venous thrombosis/pelvic vein thrombosis can cause a life-threatening pulmonary embolism during the acute phase of the disease. The postthrombotic syndrome is characterized by the remodeling of the affected venous section, which is often caused by inflammation. Locally, the typical clinical finding is caused by scarred stricture of the vein with restricted drainage and peripheral venous hypertension. Acute thrombosis should be primarily treated by therapeutic anticoagulation and compression therapy of the affected extremity. The duration of these measures depends on clinical presentation, cause (provoked, unprovoked) and risk factors for venous thrombosis/recurrent thrombosis. Venous revascularization procedures are important both in the acute phase of the disease and in the treatment of postthrombotic syndrome. The recanalization treatment is mostly carried out as an endovascular or hybrid intervention and venous bypass procedures are reserved for special situations.

French Canadian cross-cultural adaptation of CAPTSure©, an index for the Clinical Assessment of Post-Thrombotic Syndrome in children.

PURPOSE: Post-thrombotic syndrome (PTS) is the most common complication of deep venous thrombosis (DVT). The index for the Clinical Assessment of Post-Thrombotic Syndrome in children (CAPTSure©) is a clinical tool for the diagnosis and severity rating of PTS in pediatric patients. The purpose of this study was to translate and adapt CAPTSure© for French-speaking patients. METHODS: We conducted a cross-sectional study to perform linguistic and cultural adaptation of CAPTSure©, using a rigorous translation process followed by cognitive debriefings in twenty French-speaking pediatric patients aged up to 18 years old with a history of upper or lower extremity DVT at least 6 months prior. RESULTS: Forward and backward translations were used to produce a pre-final French version of CAPTSure©, followed by cognitive debriefings in twenty participants (median age: 11.5 years, 55% male, median CAPTSure© score: 26). The participants felt that the questionnaire was thorough, with an adequate length. Eight out of fourteen (57%) items in the LE questionnaire and 7/12 (58%) of the items in the UE questionnaire were modified following participants' and a multidisciplinary expert committee's input, leading to the final French version of CAPTSure©. CONCLUSIONS: CAPTSure© was successfully adapted for French-speaking pediatric patients. This will ease the diagnosis and severity rating of PTS in children in clinical practice and allow international research collaborations for additional non-English-speaking patients.

Percutaneous mechanical thrombectomy to remove post-thrombotic obstructions and manage post-thrombotic syndrome-associated venous leg ulceration.

BACKGROUND: Up to one half of patients with a diagnosis of deep vein thrombosis will develop post-thrombotic syndrome (PTS). Patients with PTS can develop venous leg ulcers (VLUs) due to post-thrombotic obstructions (PTOs) that contribute to prolonged ambulatory venous hypertension. The current treatments for PTS, which include chronic thrombus, synechiae, trabeculations, and inflow lesions, do not target PTOs, and such obstructions can affect stenting success. The aim of the present study was to determine whether removal of chronic PTOs using percutaneous mechanical thrombectomy would promote VLU resolution and positive outcomes. METHODS: In this retrospective analysis, the characteristics and outcomes for patients with VLUs secondary to chronic PTO who were treated using the ClotTriever System (Inari Medical) between August 2021 and May 2022 were assessed. Technical success was considered the ability to cross a lesion and introduce the thrombectomy device. Clinical success was defined as a decrease of ≥1 in the severity category for the ulcer diameter using the revised venous clinical severity score (score 0, no VLU; score 1, mild VLU [size <2 cm]; score 2, moderate VLU [size 2-6 cm]; score 3, severe VLU [size >6 cm]) at the latest follow-up visit. RESULTS: A total of 11 patients with 15 VLUs on 14 limbs were identified. Their mean age was 59.7 ± 11.8 years, and four patients (36.4%) were women. The median VLU duration was 11.0 months (interquartile range [IQR], 6.0-17.0 months), and 2 patients had VLUs secondary to a deep vein thrombosis event >40 years previously. All treatments were performed in a single session, with technical success achieved in 100% of the 14 limbs. A median of five passes (IQR, four to six passes) with the ClotTriever catheter were performed per limb. Chronic PTOs were successfully extirpated, and intraprocedural intravascular ultrasound showed effective disruption of venous synechiae and trabeculations. Stents were placed in 10 limbs (71.4%). The time to VLU resolution or the latest follow-up was 12.8 ± 10.5 weeks, and clinical success was achieved for all 15 VLUs (100%), with the revised venous clinical severity score for the ulcer diameter improving from a median of 2 (IQR, 2-2) at baseline to a median score of 0 (IQR, 0-0) at last follow-up. The VLU area had decreased by 96.6% ± 8.7%. Of the 15 VLUs, 12 (80.0%) had resolved completely, and 3 had demonstrated near-complete healing. CONCLUSIONS: All patients showed complete or near-complete VLU healing within a few months after mechanical thrombectomy. Mechanical extirpation and interruption of chronic PTOs allowed for luminal gain and restoration of cephalad inflow. With additional investigation, mechanical thrombectomy with the study device could prove a vital component to the treatment of VLUs secondary to PTOs.

Meta-analysis of lytic catheter-based intervention for acute proximal deep vein thrombosis in the reduction of post-thrombotic syndrome.

OBJECTIVE: Post-thrombotic syndrome (PTS) is a common complication of deep vein thrombosis (DVT) that can result in significant morbidity for the patient with detrimental impact on their quality of life. Evidence supporting lytic catheter-based interventions (LCBI) undertaken for early thrombus reduction in acute proximal DVT for the prevention of PTS is conflicting. Despite this, rates of LCBIs are increasing. To summaries the existing evidence and pool treatment effects, a meta-analysis of randomized controlled trials assessing the efficacy of LCBIs in proximal acute DVT for the prevention of PTS was undertaken. METHODS: This meta-analysis was undertaken aligning with PRISMA guidelines following a protocol pre-registered on PROSPERO. Online searches of Medline and Embase databases, as well as the gray literature, were performed up to December 2022. Included articles were randomized controlled trials that studied the use of LCBIs with additional anticoagulation vs anticoagulation alone and had determined follow-up periods. Outcomes of interest were PTS development, moderate to severe PTS, major bleeding episodes, and quality-of-life measures. Subgroup analyses were performed for DVTs involving the iliac vein and/r common femoral vein. Meta-analysis was performed using a fixed effects model. Quality assessment was performed using the Cochrane Risk of Bias and GRADE assessment tools. RESULTS: Three trials were included in the final meta-analysis, the Post-thrombotic Syndrome after Catheter-directed Thrombolysis for Deep Vein Thrombosis (CaVenT), Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis (ATTRACT), and Ultrasound-accelerated Catheter-directed Thrombolysis Versus Anticoagulation for the Prevention of Post-thrombotic Syndrome (CAVA) trials, comprising 987 patients. Patients undergoing LCBIs had a reduced risk of PTS (relative risk [RR], 0.84; 95% confidence interval [CI], 0.74-0.95; P = .006) and a lower risk of developing moderate to severe PTS (RR, 0.75; 95% CI, 0.58-0.97; P = .03). LBCIs increased the risk of having a major bleed (RR, 2.03; 95% CI, 1.08-3.82; P = .03). In the iliofemoral DVT subgroup analysis, there was a trend toward decreasing the risk of developing PTS and moderate to severe PTS (P = .12 and P = .05, respectively). There was no significant difference in quality-of-life score (as measured by the Venous Insufficiency Epidemiological and Economic Study - Quality of Life/Symptoms) between the two groups (P = .51). CONCLUSIONS: Pooling of current best evidence suggests that LCBIs in acute proximal DVT decreases the rate of PTS and moderate to severe PTS with a number needed to treat of 12 and 18, respectively. However, this is complicated by a significantly higher rate of major bleeding with a number needed to treat of 37. This evidence supports the use of LCBIs in selected patients, including those who are at low risk of major bleeding.

Residual Venous Obstruction as an Indicator of Clinical Outcomes following Deep Vein Thrombosis: A Management Study.

BACKGROUND: Residual venous obstruction (RVO) is considered a risk factor of recurrence and possibly other clinical outcomes following deep vein thrombosis (DVT). Current guidelines do not support an RVO-tailored duration of anticoagulant therapy; contemporary data of such management strategies are scarce. We aimed to evaluate an RVO-based management strategy and to assess associations of RVO with recurrence, post-thrombotic syndrome (PTS), arterial events and cancer. To gain further insight, D-dimer levels were measured 1 month after stopping anticoagulant therapy. METHODS: Consecutive patients with symptomatic, proximal DVT were treated in a 2-year clinical care pathway (CCP) at Maastricht University Medical Center and were followed up to 5 years. RVO was assessed at the end of regular duration of anticoagulant therapy, which was extended once if RVO was detected. The study was approved by the medical ethics committee. RESULT: From a total of 825 patients, 804 patients (97.5%) completed the CCP and 755 (93.9%) were available for extended follow-up. Most patients (76.5%) stopped anticoagulant therapy. Incidence rates of recurrence, PTS, arterial events, and cancer were 4.4, 11.9, 1.7, and 1.8 per 100 patient-years, respectively. RVO was independently associated with PTS (hazard ratio [HR]: 1.66 [1.19-2.32]) and arterial events (HR: 2.07 [1.18-3.65]), but not with recurrence or cancer. High D-dimer was associated with recurrence (HR: 3.51 [2.24-5.48]). CONCLUSION: Our RVO-based management strategy might have attenuated the association of RVO with recurrence. In addition, RVO identified patients at increased risk of PTS and arterial events, which might be used to identify patients in need of alternative treatment strategies.

Thrombus Signal on T1-Weighted Black-Blood MR Predicts Outcomes of Catheter-Directed Thrombolysis in Acute Deep Vein Thrombosis.

OBJECTIVES: Catheter-directed thrombolysis (CDT) is an effective therapy for acute deep vein thrombosis (DVT). However, predicting the CDT outcomes remains elusive. We hypothesized that the thrombus signal on T1-weighted black-blood magnetic resonance (MR) can provide insight into CDT outcomes in acute DVT patients. METHODS: A total of 117 patients with acute iliofemoral DVT were enrolled for T1-weighted black-blood MR before CDT in this prospective study. Based on the signal contrast between thrombus and adjacent muscle, patients were categorized into the iso-intense thrombus (Iso-IT), hyper-intense thrombus (Hyper-IT), and mixed iso-/hyper-intense thrombi (Mixed-IT) groups. Immediate treatment outcome (i.e., vein patency) and long-term treatment outcome (i.e., the incidence rate of postthrombotic syndrome) were accessed by the same expert. Histological analysis and iron quantification were performed on thrombus samples to characterize the content of fibrin, collagen, and the ratio of Fe3+ to total iron. RESULTS: Compared to Mixed-IT and Hyper-IT groups, the Iso-IT group had the best lytic effect (90.5 ± 1.6% vs. 78.4 ± 2.6% vs. 46.5 ± 3.3%, p < 0.001), lowest bleeding ratio (0.0 vs. 11.8 vs. 13.3, p < 0.001), and the lowest incidence rate of postthrombotic syndrome on 24 months (3.6 vs. 18.4 vs. 63.4%, p < 0.001) following CDT. The Iso-IT group had a significantly lower ratio of Fe3+ to total iron (93.1 ± 3.2% vs. 97.2 ± 2.1%, p = 0.034) and a higher content of fibrin (12.5 ± 5.3% vs. 4.76 ± 3.18%, p = 0.023) than Hyper-IT. CONCLUSION: Thrombus signal characteristics on T1-weighted black-blood MR is associated with CDT outcomes and possesses potential to serve as a noninvasive approach to guide treatment decision making in acute DVT patients. KEY POINTS: · Thrombus signal on T1-weighted black-blood MR is associated with lytic therapeutic outcome in acute DVT patients.. · Presence of iso-intense thrombus revealed by T1-weighted black-blood MRI is associated with successful thrombolysis, low bleeding ratio, and low incidence of the postthrombotic syndrome.. · T1-weighted thrombus signal characteristics may serve as a noninvasive imaging marker to predict CDT treatment outcomes and therefore guide treatment decision making in acute DVT patients..

[Postthrombotic syndome-a complex clinical picture]. / Postthrombotisches Syndrom ­ ein komplexes Krankheitsbild.

Postthrombotic syndrome (PTS), which comprises a range of symptoms and signs following the development of deep vein thrombosis, is associated with varied clinical presentation. The functional limitations associated with PTS may be persistent, and following deep vein thrombosis, the patient may require lifelong anticoagulation. Venous ulceration is often regarded as a complication of PTS. However, the development of venous ulceration strictly depends on underlying venous hypertension, which is not always present. Due to the heterogenous clinical presentation of PTS, diagnosis may be difficult. Nevertheless, accurate diagnosis is vital and modern imaging techniques can help establish the diagnosis and play a role in monitoring treatment response. Thus, in addition to new strategies in compression therapy, (endo)vascular interventions are established treatment modalities in the management of PTS.

Performance and Head-to-Head Comparison of Three Clinical Models to Predict Occurrence of Postthrombotic Syndrome: A Validation Study.

OBJECTIVE: The SOX-PTS, Amin, and Méan models are three different clinical prediction scores stratifying the risk for postthrombotic syndrome (PTS) development in patients with acute deep vein thrombosis (DVT) of the lower limbs. Herein, we aimed to assess and compare these scores in the same cohort of patients. METHODS: We retrospectively applied the three scores in a cohort of 181 patients (196 limbs) who participated in the SAVER pilot trial for an acute DVT. Patients were stratified into PTS risk groups using positivity thresholds for high-risk patients as proposed in the derivation studies. All patients were assessed for PTS 6 months after index DVT using the Villalta scale. We calculated the predictive accuracy for PTS and area under receiver operating characteristic (AUROC) curve for each model. RESULTS: The Méan model was the most sensitive (sensitivity 87.7%; 95% confidence interval [CI]: 77.2-94.5) with the highest negative predictive value (87.5%; 95% CI: 76.8-94.4) for PTS. The SOX-PTS was the most specific score (specificity 97.5%; 95% CI: 92.7-99.5) with the highest positive predictive value (72.7%; 95% CI: 39.0-94.0). The SOX-PTS and Méan models performed well for PTS prediction (AUROC: 0.72; 95% CI: 0.65-0.80 and 0.74; 95% CI: 0.67-0.82), whereas the Amin model did not (AUROC: 0.58; 95% CI: 0.49-0.67). CONCLUSION: Our data support that the SOX-PTS and Méan models have good accuracy to stratify the risk for PTS.

Developing and optimizing a machine learning predictive model for post-thrombotic syndrome in a longitudinal cohort of patients with proximal deep venous thrombosis.

BACKGROUND: Post-thrombotic syndrome (PTS) is the most common chronic complication of deep venous thrombosis (DVT). Risk measurement and stratification of PTS are crucial for patients with DVT. This study aimed to develop predictive models of PTS using machine learning for patients with proximal DVT. METHODS: Herein, hospital inpatients from a DVT registry electronic health record database were randomly divided into a derivation and a validation set, and four predictive models were constructed using logistic regression, simple decision tree, eXtreme Gradient Boosting (XGBoost), and random forest (RF) algorithms. The presence of PTS was defined according to the Villalta scale. The areas under the receiver operating characteristic curves, decision-curve analysis, and calibration curves were applied to evaluate the performance of these models. The Shapley Additive exPlanations analysis was performed to explain the predictive models. RESULTS: Among the 300 patients, 126 developed a PTS at 6 months after DVT. The RF model exhibited the best performance among the four models, with an area under the receiver operating characteristic curves of 0.891. The RF model demonstrated that Villalta score at admission, age, body mass index, and pain on calf compression were significant predictors for PTS, with accurate prediction at the individual level. The Shapley Additive exPlanations analysis suggested a nonlinear correlation between age and PTS, with two peak ages of onset at 50 and 70 years. CONCLUSIONS: The current predictive model identified significant predictors and accurately predicted PTS for patients with proximal DVT. Moreover, the model demonstrated a nonlinear correlation between age and PTS, which might be valuable in risk measurement and stratification of PTS in patients with proximal DVT.

Double-barrel iliocaval reconstruction using closed-cell dedicated venous stents.

OBJECTIVE: Double-barrel iliocaval reconstruction is performed by deploying two stents simultaneously in a side-by-side, or "double-barrel," configuration in the inferior vena cava (IVC) with extension into the bilateral common iliac veins. The aim of this study was to examine the outcomes of double-barrel reconstruction using closed-cell dedicated venous stents for the treatment of iliocaval deep venous thrombosis and iliac vein compression syndrome. METHODS: All endovascular procedural reports comprising vascular surgery and interventional radiology operators from a single urban academic hospital between May 1, 2019, and April 30, 2021, were retrospectively searched. A cohort of 22 consecutive patients who underwent double-barrel iliocaval stenting with closed-cell dedicated venous stents for chronic or acute-on-chronic iliocaval venous disease without prior endovascular iliocaval repair was identified. Baseline characteristics, procedural data, and patient outcomes were determined via a manual review of preprocedure clinical notes, diagnostic imaging studies, procedure notes and images, and follow-up clinical notes. RESULTS: The median (range) age was 59 (27-81) years, and the cohort consisted of 59.1% female. The most common presenting symptoms of venous disease were lower extremity swelling (90.9%) and pain (50.0%). CEAP clinical classification was C3 in 86.4% of patients, whereas the remainder had C4 disease. Most patients (72.7%) had post-thrombotic syndrome, 22.7% had a nonthrombotic iliac vein lesion, and one patient (4.5%) had the congenital absence of the infrarenal IVC. A total of 40.9% of patients had a pre-existing IVC filter at the time of treatment. Six of the 22 patients underwent concurrent pharmacomechanical thrombectomy during the index iliocaval reconstruction and stenting procedure. The number of stents placed ranged from 2 to 5. With a mean follow-up period of 7.1 months, ranging from 12 days to 16.7 months, the freedom from reintervention rate was 90.9%. Twenty of 22 patients achieved subjective improvement or resolution of symptoms. The major adverse event rate was 9.1%, as two patients had access site complications requiring intervention. CONCLUSIONS: Double-barrel iliocaval reconstruction with closed-cell dedicated venous stents for the treatment of post-thrombotic syndrome or iliac vein compression syndrome is technically feasible and clinically effective with a low reintervention rate.

Assessment of the lymphatic system by indirect lymphography in patients with post-thrombotic syndrome.

OBJECTIVE: Alterations in lower extremity lymph drainage caused by chronic venous obstruction (CVO) have not been well studied, partially because of a lack of standardized imaging modalities to assess the quality of lymphatic drainage in the lower extremities of patients with post-thrombotic syndrome (PTS). However, these changes are likely to have an impact on the severity of the disease and clinical outcomes of interventions. In the present study, we investigated the feasibility and diagnostic value of preintervention indirect lymphography in patients with CVO and their pre- and postintervention Villalta scores. METHODS: A total of 17 patients (21 limbs) with iliofemoral and caval CVO were included in the study between 2017 and 2018. The deep and superficial lymphatic vessels in both legs were assessed before venous recanalization and stenting. The quality of lymphatic flow was compared between the legs with CVO and healthy legs. Moreover, the correlation between the lymphatic changes and clinical severity of PTS was evaluated using the Villalta score and CEAP (Clinical, Etiology, Anatomy, and Pathophysiology) classification. RESULTS: The mean patient age was 44 ± 12 years, and 10 patients (59%) were women. The patients had undergone treatment at a mean of 25 ± 6 months after their first episode of deep vein thrombosis. Five patients (29%) had had recurrent deep vein thrombosis. The mean pre- and postinterventional Villalta score was 10.5 ± 1.46 and 9.27 ± 1.12, respectively (P = .0096). Using the CEAP classification, four legs were class 5, seven were class 4, and three each were class 3 and 2. The primary and secondary patency rate was 70.5% and 82.5% after a mean follow-up of 18 months, respectively. Indirect lymphography of the superficial and deep lymphatic systems was completed before intervention in both legs for all 17 patients (21 legs). According to the qualitative criteria, abnormal lymphatic vessel function was found in 35.2% of the superficial and 58.8% of the deep lymphatic vessels of the affected legs. Further analysis revealed abnormal function of the deep lymphatic vessels in all patients with moderate to severe PTS according to the Villalta score. CONCLUSIONS: Indirect lymphography is a feasible diagnostic tool to use for the evaluation of the function of lymphatic vessels. Impaired drainage of the deep lymphatic system was found in all our patients with moderate to severe PTS. The clinical significance of these lymphatic changes is not clear; however, an association between clinical severity and outcomes is possible.

Risk factors and classification of reintervention following deep venous stenting for acute iliofemoral deep vein thrombosis.

BACKGROUND: Acute iliofemoral deep vein thrombosis (DVT) is associated with the development of post-thrombotic syndrome (PTS). Thrombolysis and deep venous stenting can restore vessel outflow and can reduce the incidence of PTS. However, for a proportion of patients, subsequent stenosis or reocclusion will necessitate further intervention. In the present study, we aimed to identify the risk factors, examine the outcomes (reintervention success and PTS), and develop a classification system for reintervention. METHODS: A retrospective single-center cohort study of patients who had undergone successful lysis for iliofemoral DVT from 2013 to 2017. The patients' records and imaging studies were examined for demographics, risk factors, extent of thrombus and vessel clearance, stenting, flow, reintervention, anticoagulation compliance, Villalta score, and secondary patency. From our findings, a system of classification for patients for whom procedures have failed was developed, constituting technical, hematologic, flow related, or multiple factors. RESULTS: Of 143 limbs (133 patients), 48 (33.6%) had required reintervention, of which 25 had presented with reocclusion (17.4%). The median time to reintervention was 45 days. The need for reintervention was associated with inferior vena cava thrombus (risk ratio [RR], 2.16; P < .01), stenting across the inguinal ligament (RR, 2.08; P < .01), and anticoagulation noncompliance (RR, 7.09; P < .01). Successful reintervention was achieved in 31 limbs (64.6%): 23 of 23 (100%) treated before occlusion vs 8 of 25 (36.4%) treated after occlusion (RR, 32.31; P < .01). A greater incidence of any PTS was observed for patients requiring reintervention (median Villalta score, 3 [interquartile range, 1-5]; vs 1 [interquartile range, 1-4]; RR, 2.28; P = .029). Cases without complete vessel occlusion (reintervention and control) had a lower rate of any PTS (14.0% vs 42.9%; RR, 3.06; P < .01) and moderate to severe PTS (3.0% vs 14.3%; RR, 4.76; P = .046) Technical issues were observed in 54.2% of reintervention cases and 6.3% of cases not requiring reintervention (P < .01). Hematologic issues were identified in 33.3% of reintervention cases and 1.1% of cases not requiring reintervention (P < .01). Flow-related issues were observed in 43.8% of the reintervention cases and no cases not requiring reintervention (P < .01). Of the reintervention cases, 27.1% were multifactorial and were associated with a lower rate of vessel salvage; however, this did not translate into a significant difference in secondary patency on survival analysis (RR, 1.70; P = .429). CONCLUSIONS: A large proportion of patients required reintervention because of potentially preventable factors. Anticoagulation compliance, thrombus burden, and poor flow are important risk factors to consider in patient selection. Reintervention increased the risk of PTS and was more often successful when achieved before vessel occlusion.

Interim outcomes of mechanical thrombectomy for deep vein thrombosis from the All-Comer CLOUT Registry.

OBJECTIVES: The multicenter, prospective, single arm CLOUT registry assesses the safety and effectiveness of the ClotTriever System (Inari Medical, Irvine, CA) for the treatment of acute and nonacute lower extremity deep vein thrombosis (DVT) in all-comer patients. Reported here are the outcomes of the first 250 patients. METHODS: All-comer patients with lower extremity DVT were enrolled, including those with bilateral DVT, those with previously failed DVT treatment, and regardless of symptom duration. The primary effectiveness end point is complete or near-complete (≥75%) thrombus removal determined by independent core laboratory-adjudicated Marder scores. Safety outcomes include serious adverse events through 30 days and clinical outcomes include post-thrombotic syndrome severity, symptoms, pain, and quality of life through 6 months. RESULTS: The median age was 62 years and 40% of patients had contraindications to thrombolytics. A range of thrombus chronicity (33% acute, 35% subacute, 32% chronic) was observed. No patients received thrombolytics and 99.6% were treated in a single session. The median thrombectomy time was 28 minutes. The primary effectiveness end point was achieved in 86% of limbs. Through 30 days, one device-related serious adverse event occurred. At 6 months, 24% of patients had post-thrombotic syndrome. Significant and sustained improvements were observed in all clinical outcomes, including the Revised Venous Clinical Severity Score, the numeric pain rating scale, and the EuroQol Group 5-Dimension Self-Report Questionnaire. CONCLUSIONS: The 6-month outcomes from the all-comer CLOUT registry with a range of thrombus chronicities demonstrate favorable effectiveness, safety, and sustained clinical improvements.

External Validation of the Patient-Reported Villalta Scale for the Diagnosis of Postthrombotic Syndrome.

INTRODUCTION: The Villalta scale is the endorsed tool to diagnose and grade the severity of postthrombotic syndrome (PTS); however, assessing presence and severity of PTS is time-consuming and relies on both the clinician and patient's assessments. The patient-reported Villalta scale version 2 (PRV2) is a visually assisted form that enables patients to self-assess presence and severity of PTS. Herein, we report on external validation of this tool. METHODS: We assessed the agreement and kappa values of PRV2 to diagnose and assess severity of PTS compared with the original Villalta score in a cohort of 181 patients (196 limbs) who participated in the SAVER pilot randomized control trial. Presence of PTS was defined as PRV2 ≥5 or a Villalta score ≥5. RESULTS: PTS prevalence was 42% using PRV2 and 33% using the Villalta scale. The corresponding kappa and percentage agreement were 0.60 (95% confidence interval [CI]: 0.49-0.71) and 81% (95% CI: 76-87), respectively. Kappa values and percentage agreements between PRV2 and Villalta scale increased with increasing severity of PTS. The sensitivity of PRV2 to detect PTS of any severity was 84% (95% CI: 73-92) with a specificity of 79% (95% CI: 71-86). CONCLUSION: We conclude that the PRV2 is an acceptable tool for diagnosing and grading the severity of PTS.

Pharmacomechanical catheter-directed thrombolysis for acute iliofemoral deep vein thrombosis in a large study population.

BACKGROUND: We have analyzed our single-center immediate and follow-up results in the management of acute iliofemoral deep vein thrombosis (IFDVT) using pharmacomechanical catheter-directed thrombolysis (PMCDT) to determine the safety, accuracy, and effects on quality of life and whether this treatment strategy prevents post-thrombotic syndrome (PTS). METHODS: The cases of 230 patients who had undergone PMCDT to treat IFDVT from January 2017 to December 2018 were retrospectively reviewed. The preoperative, operative, and postoperative variables, Marder scores, outcomes, and follow-up assessments with the Villalta score and venous clinical severity score were investigated. RESULTS: Anatomic success was achieved for 95.2% of the 230 patients. The mean Marder score had decreased from 12.65 ± 2.1 to 2.4 ± 1.3 postoperatively (P < .01). Early recurrent thrombosis had developed in 13 patients (5.65%). The primary patency at the 1-, 6-, and 12-month follow-up visits was 94.0%, 87.2%, and 81.7%, respectively. From 1 to 6 months, the Villalta score had decreased from 8.32 ± 4.14 to 3.43 ± 0.61 and the venous clinical severity score had decreased from 4.0 ± 1.8 to 1.82 ± 0.36 (P < .05). No statistically significant difference was found in the PTS severity scores at 12 months of follow-up compared with at 6 months. The mean change in the venous disease-specific quality of life from baseline to 12 months was 29.41 ± 1.99 (P = .029). The total recurrence rate was 19.63% at 1 year. CONCLUSIONS: For a select group of patients with acute IFDVT, the use of PMCDT and postoperative anticoagulation therapy offered significant reductions in clot burden, leg pain, and swelling, achieving a significant reduction in PTS severity scores at 6 months.

Prevention of the Postthrombotic Syndrome with Anticoagulation: A Narrative Review.

The postthrombotic syndrome (PTS) is chronic venous insufficiency secondary to a prior deep vein thrombosis (DVT). It is the most common complication of venous thromboembolism (VTE) and, while not fatal, it can lead to chronic, unremitting symptoms as well as societal and economic consequences. The cornerstone of PTS treatment lies in its prevention after DVT. Specific PTS preventative measures include the use of elastic compression stockings and pharmacomechanical catheter-directed thrombolysis. However, the efficacy of these treatments has been questioned by large randomized controlled trials (RCTs). So far, anticoagulation, primarily prescribed to prevent DVT extension and recurrence, appears to be the only unquestionably effective treatment for the prevention of PTS. In this literature review we present pathophysiological, biological, radiological, and clinical data supporting the efficacy of anticoagulants to prevent PTS and the possible differential efficacy among available classes of anticoagulants (vitamin K antagonists [VKAs], low molecular weight heparins [LMWHs] and direct oral anticoagulants [DOACs]). Data suggest that LMWHs and DOACs are superior to VKAs, but no head-to-head comparison is available between DOACs and LMWHs. Owing to their potentially greater anti-inflammatory properties, LMWHs could be superior to DOACs. This finding may be of interest particularly in patients with extensive DVT at high risk of moderate to severe PTS, but needs to be confirmed by a dedicated RCT.