Developmental or Procedural Vena Cava Interruption and Venous Thromboembolism: A Review.

The inferior vena cava (IVC) and superior vena cava are the main conduits of the systemic venous circulation into the right atrium. Developmental or procedural interruptions of vena cava might predispose to stasis and deep vein thrombosis (DVT) distal to the anomaly and may impact the subsequent rate of pulmonary embolism (PE). This study aimed to review the various etiologies of developmental or procedural vena cava interruption and their impact on venous thromboembolism. A systematic search was performed in PubMed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines per each clinical question. For management questions with no high-quality evidence and no mutual agreements between authors, Delphi methods were used. IVC agenesis is the most common form of congenital vena cava interruption, is associated with an increased risk of DVT, and should be suspected in young patients with unexpected extensive bilateral DVT. Surgical techniques for vena cava interruption (ligation, clipping, and plication) to prevent PE have been largely abandoned due to short-term procedural risks and long-term complications, although survivors of prior procedures are occasionally encountered. Vena cava filters are now the most commonly used method of procedural interruption, frequently placed in the infrarenal IVC. The most agreed-upon indication for vena cava filters is for patients with acute venous thromboembolism and coexisting contraindications to anticoagulation. Familiarity with different forms of vena cava interruption and their local and systemic adverse effects is important to minimize complications and thrombotic events.

Research Consensus Panel Follow-up: 8-Year Update on Submassive Pulmonary Embolism.

The 2015 Research Consensus Panel (RCP) on submassive pulmonary embolism (PE) set priorities for research in submassive PE and identified a rigorous randomized trial of catheter-directed therapy plus anticoagulation versus anticoagulation alone as the highest research priority. This update, written 8 years after the RCP was convened, describes the current state of endovascular PE practice and the Pulmonary Embolism-Thrombus Removal with Catheter-Directed Therapy trial, the main output from the RCP.

Society of Interventional Radiology Position Statement on the Management of Chronic Iliofemoral Venous Obstruction with Endovascular Placement of Metallic Stents.

PURPOSE: To state the position of the Society of Interventional Radiology (SIR) on the endovascular management of chronic iliofemoral venous obstruction with metallic stents. MATERIALS AND METHODS: A multidisciplinary writing group with expertise in treating venous disease was convened by SIR. A comprehensive literature search was conducted to identify studies on the topic of interest. Recommendations were drafted and graded according to the updated SIR evidence grading system. A modified Delphi technique was used to achieve consensus agreement on the recommendation statements. RESULTS: A total of 41 studies, including randomized trials, systematic reviews and meta-analyses, prospective single-arm studies, and retrospective studies were identified. The expert writing group developed 15 recommendations on the use of endovascular stent placement. CONCLUSIONS: SIR considers the use of endovascular stent placement for chronic iliofemoral venous obstruction to be likely to help selected patients, but the risks and benefits have not been fully quantified in well-designed randomized studies. SIR recommends urgent completion of such studies. In the meantime, careful patient selection and optimization of conservative therapy are recommended prior to stent placement, with attention to appropriate stent sizing and quality procedural technique. The use of multiplanar venography with intravascular ultrasound is suggested in diagnosing and characterizing obstructive iliac vein lesions and in guiding stent therapy. After stent placement, SIR recommends close patient follow-up to ensure optimal antithrombotic therapy, durable symptom response, and early identification of adverse events.

Delphi Consensus on Reporting Standards in Clinical Studies for Endovascular Treatment of Acute Iliofemoral Venous Thrombosis and Chronic Iliofemoral Venous Obstruction.

Acute iliofemoral deep vein thrombosis and chronic iliofemoral venous obstruction cause substantial patient harm and are increasingly managed with endovascular venous interventions, including percutaneous mechanical thrombectomy and stent placement. However, studies of these treatment elements have not been designed and reported with sufficient rigor to support confident conclusions about their clinical utility. In this project, the Trustworthy consensus-based statement approach was utilized to develop, via a structured process, consensus-based statements to guide future investigators of venous interventions. Thirty statements were drafted to encompass major topics relevant to venous study description and design, safety outcome assessment, efficacy outcome assessment, and topics specific to evaluating percutaneous venous thrombectomy and stent placement. Using modified Delphi techniques for consensus achievement, a panel of physician experts in vascular disease voted on the statements and succeeded in reaching the predefined threshold of >80% consensus (agreement or strong agreement) on all 30 statements. It is hoped that the guidance from these statements will improve standardization, objectivity, and patient-centered relevance in the reporting of clinical outcomes of endovascular interventions for acute iliofemoral deep venous thrombosis and chronic iliofemoral venous obstruction in clinical studies and thereby enhance venous patient care.

Exploring the Villalta scale to capture postthrombotic syndrome using alternative approaches: A subanalysis of the ATTRACT trial.

Background: Clinical trials that evaluated interventions to prevent postthrombotic syndrome (PTS) used the Villalta scale (VS) to define PTS, but there is a lack of consistency in its use. Objectives: This study aimed to improve the ability to identify patients with clinically meaningful PTS after DVT in participants of the ATTRACT trial. Methods: We conducted a post hoc exploratory analysis of 691 patients from the ATTRACT study, a randomized trial evaluating the effectiveness of pharmacomechanical thrombolysis to prevent PTS in proximal deep vein thrombosis. We compared 8 VS approaches to classify patients with or without PTS in terms of their ability to discriminate between those with poorer vs better venous disease-specific quality of life (Venous Insufficiency Epidemiological and Economic Study Quality of Life [VEINES-QOL]) between 6- and 24-months follow-up. The difference in the average area under the fitted curve of VEINES-QOL scores between PTS and no PTS ( Δ A U C ¯ ) were compared among approaches. Results: For any PTS (a single VS score ≥5), approaches 1 to 3 had similar Δ A U C ¯ (-21.2, -23.7, -22.0, respectively). Adjusting the VS for contralateral chronic venous insufficiency (CVI) or restricting to patients without baseline CVI (approaches 7 and 8) did not improve Δ A U C ¯ (-13.6, -19.9, respectively; P >.01). For moderate-to-severe PTS (a single VS score ≥10), approaches 5 and 6 requiring 2 positive assessments had greater but not statistically significant Δ A U C ¯ than approach 4, using one single positive assessment (-31.7, -31.0, -25.5, respectively; P >.01). Conclusion: A single VS score of ≥ 5 reliably distinguishes patients with clinically meaningful PTS as assessed by impact on QOL and is preferred because of greater convenience (only one assessment needed). Alternative methods to define PTS (ie, adjusting for CVI) do not improve the scale's ability to identify clinically meaningful PTS.

Society of Interventional Radiology Position Statement on the Endovascular Management of Acute Iliofemoral Deep Vein Thrombosis.

PURPOSE: To establish the updated position of the Society of Interventional Radiology (SIR) on the endovascular management of acute iliofemoral deep vein thrombosis (DVT). MATERIALS AND METHODS: A multidisciplinary writing group with expertise in treating venous diseases was convened by SIR. A comprehensive literature search was conducted to identify studies on the topic of interest. Recommendations were drafted and graded according to the updated SIR evidence grading system. A modified Delphi technique was used to achieve consensus agreement on the recommendation statements. RESULTS: A total of 84 studies, including randomized trials, systematic reviews and meta-analyses, prospective single-arm studies, and retrospective studies were identified and included in the review. The expert writing group developed 17 recommendations that pertain to the care of patients with acute iliofemoral DVT with the use of endovascular venous interventions. CONCLUSIONS: SIR considers endovascular thrombus removal to be an acceptable treatment option in selected patients with acute iliofemoral DVT. Careful individualized risk assessment, high-quality general DVT care, and close monitoring during and after procedures should be provided.

Peri-procedure management of antithrombotic agents and thrombocytopenia for common procedures in oncology: Guidance from the SSC of the ISTH.

Patients with cancer have an increased risk of thrombosis requiring anticoagulants and/or antiplatelet agents, and they can also encounter thrombocytopenia due to cancer itself or cancer therapies. They often undergo many procedures such as tissue or bone marrow biopsies, placement of central access lines, diagnostic or therapeutic draining procedures, lumbar puncture, and more. Management of antithrombotic agents or thrombocytopenia around the time of these procedures is highly variable. In this document, the Hemostasis and Malignancy Subcommittee of the International Society on Thrombosis and Haemostasis aims to provide useful practice guidance in the management of antithrombotic agents and thrombocytopenia around the time of common procedures in patients with cancer.

New and known predictors of the postthrombotic syndrome: A subanalysis of the ATTRACT trial.

Introduction: Postthrombotic syndrome (PTS) remains associated with significant clinical and economic burden. This study aimed to investigate known and novel predictors of the development of PTS in participants of the ATTRACT (Acute Venous Thrombosis: Thrombus Removal With Adjunctive Catheter-Directed Thrombolysis) trial. Methods: We used multivariable logistic regression to identify baseline and postbaseline factors that were predictive of the development of PTS during study follow-up, as defined by a Villalta score of 5 or greater or the development of a venous ulcer from 6 to 24 months after enrollment. Results: Among 691 patients in the study cohort (all had proximal deep vein thrombosis [DVT] that extended above the popliteal vein, of which 57% had iliofemoral DVT), 47% developed PTS. Further, we identified that Villalta score at baseline (odds ratio [OR], 1.09 [95% confidence interval [CI], 1.05-1.13] per one-unit increase) and employment status (unemployed due to disability: OR, 3.31 [95% CI, 1.72-6.35] vs. employed more than 35 hours per week) were predictive of PTS. In terms of postbaseline predictors, leg pain severity at day 10 (OR, 1.28 [95% CI, 1.13-1.45] per 1-point increase in a 7-point scale) predicted PTS. Also, patients receiving rivaroxaban on day 10 following randomization had lower rates of PTS (OR, 0.53 [95% CI, 0.33-0.86]) than patients on warfarin. Conclusions: Novel predictors for PTS identified in our study include baseline Villalta score, leg pain severity at 10 days, and unemployed due to disability. Our findings also suggest that the initial choice of anticoagulant to treat DVT may have an impact on the development of PTS.

Predictors of Clinical Outcomes of Pharmacomechanical Catheter-Directed Thrombolysis for Acute Iliofemoral Deep Vein Thrombosis: Analysis of a Multicenter Randomized Trial.

PURPOSE: To identify the baseline patient characteristics that predict who will benefit from pharmacomechanical catheter-directed thrombolysis (PCDT) of acute iliofemoral deep vein thrombosis (DVT). MATERIALS AND METHODS: In the Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis (ATTRACT) multicenter randomized trial, 381 patients with acute iliofemoral DVT underwent PCDT and anticoagulation or anticoagulation alone. The correlations between baseline factors and venous clinical outcomes were evaluated over 24 months using post hoc regression analyses. Interaction terms were examined to evaluate for differential effects by treatment arm. RESULTS: Patients with clinically severe DVT (higher baseline Villalta score) experienced greater effects of PCDT in improving 24-month venous outcomes, including moderate or severe postthrombotic syndrome (PTS) (odds ratios [ORs] and 95% confidence intervals [CIs] per unit increase in the baseline Villalta scores were as follows: for PCDT, OR, 1.08 [95% CI, 1.01-1.15]; for control, OR, 1.20 [95% CI, 1.12-1.29]; Pinteraction = .03), PTS severity (between-arm differences in the Villalta [Pinteraction = .004] and Venous Clinical Severity Scale [VCSS] [Pinteraction = .002)] scores), and quality of life (between-arm difference in the Venous Insufficiency Epidemiological and Economic Study Quality of Life score; Pinteraction = .025). Patients with previous DVT had greater effects of PCDT on 24-month PTS severity than those in patients without previous DVT (mean [95% CI] between-arm difference in the Villalta score, 4.2 [1.56-6.84] vs 0.9 [-0.44 to 2.26], Pinteraction = .03; mean [95% CI] between-arm difference in the VCSS score, 2.6 [0.94-4.21] vs 0.3 [-0.58 to 1.14], Pinteraction = .02). The effects of PCDT on some but not all outcomes were greater in patients presenting with left-sided DVT (Villalta PTS severity, Pinteraction = .04; venous ulcer, Pinteraction = .0499) or a noncompressible popliteal vein (PTS, Pinteraction = .02). The effects of PCDT did not vary by sex, race, ethnicity, body mass index, symptom duration, hypertension, diabetes, or hypercholesterolemia. CONCLUSIONS: In patients with acute iliofemoral DVT, greater presenting clinical severity (higher baseline Villalta score) and a history of previous DVT predict enhanced benefits from PCDT.

Closing the Gaps in Racial Disparities in Critical Limb Ischemia Outcome and Amputation Rates: Proceedings from a Society of Interventional Radiology Foundation Research Consensus Panel.

Minority patients such as Blacks, Hispanics, and Native Americans are disproportionately impacted by critical limb ischemia and amputation due to multiple factors such as socioeconomic status, type or lack of insurance, lack of access to health care, capacity and expertise of local hospitals, prevalence of diabetes, and unconscious bias. The Society of Interventional Radiology Foundation recognizes that it is imperative to close the disparity gaps and funded a Research Consensus Panel to prioritize a research agenda. The following research priorities were ultimately prioritized: (a) randomized controlled trial with peripheral arterial disease screening of at-risk patients with oversampling of high-risk racial groups, (b) prospective trial with the introduction of an intervention to alter a social determinant of health, and (c) a prospective trial with the implementation of an algorithm that requires criteria be met prior to an amputation. This article presents the proceedings and recommendations from the panel.

A Clinical Trial of Venous Stent Placement for Post-thrombotic Syndrome: Current Status and Pandemic-related Changes.

Patients with post-thrombotic syndrome (PTS) and iliac vein obstruction have lower extremity symptoms, activity limitation and impairment of health-related quality of life. Preliminary studies suggest that iliac vein stent placement, which eliminates venous outflow obstruction, may reduce the clinical severity of PTS. However, stent placement is associated with patient risk, inconvenience and cost. Therefore, the Chronic Venous Thrombosis - Relief with Adjunctive Catheter-directed Therapy (C-TRACT) trial was launched to rigorously assess the risk-benefit ratio of stent placement for the treatment of moderate or severe PTS. In the trial, patients in both treatment groups receive a high quality of multimodality PTS care that includes medical, compressive, and ulcer therapies. Due to the COVID-19 pandemic, the trial protocol and practices were modified to enhance the study feasibility while preserving its ability to answer its primary question. This review summarises the current status of the trial and the potential impact of the pandemic-related adaptations to future venous clinical practice and research.

Optimal Medical Therapy Following Deep Venous Interventions: Proceedings from the Society of Interventional Radiology Foundation Research Consensus Panel.

The optimal medical management of patients following endovascular deep venous interventions remains ill-defined. As such, the Society of Interventional Radiology Foundation (SIRF) convened a multidisciplinary group of experts in a virtual Research Consensus Panel (RCP) to develop a prioritized research agenda regarding antithrombotic therapy following deep venous interventions. The panelists presented the gaps in knowledge followed by discussion and ranking of research priorities based on clinical relevance, overall impact, and technical feasibility. The following research topics were identified as high priority: 1) characterization of biological processes leading to in-stent stenosis/rethrombosis; 2) identification and validation of methods to assess venous flow dynamics and their effect on stent failure; 3) elucidation of the role of inflammation and anti-inflammatory therapies; and 4) clinical studies to compare antithrombotic strategies and improve venous outcome assessment. Collaborative, multicenter research is necessary to answer these questions and thereby enhance the care of patients with venous disease.

Catheter-directed thrombolysis for deep vein thrombosis: 2021 update.

Catheter-directed thrombolysis (CDT) has been utilized as an adjunct to anticoagulant therapy in selected patients with deep vein thrombosis (DVT) for approximately 30 years. CDT used to be limited to patients with DVT causing acute limb threat and those exhibiting failure of initial anticoagulation, but has expanded over time. Randomized trials evaluating the first-line use of CDT for proximal DVT have demonstrated that CDT does not produce a major reduction in the occurrence of post-thrombotic syndrome (PTS) and that it is poorly suited for elderly patients and those with limited thrombus extent or major risk factors for bleeding. However, CDT does offer selected patients with acute iliofemoral DVT improvement in reducing early DVT symptoms, in achieving reduction in PTS severity, and in producing an improvement in health-related quality of life (QOL). Clinical practice guidelines from medical and surgical societies are now largely aligned with the randomized trial results. This review offers the reader an update on the results of recently completed clinical trials, and additional guidance on appropriate selection of patients with DVT for catheter-directed thrombolytic therapy.

Clinical Outcomes of a Pharmacomechanical Catheter-Directed Venous Thrombolysis Strategy that Included Rheolytic Thrombectomy in a Multicenter Randomized Trial.

PURPOSE: To describe the clinical outcomes of a pharmacomechanical catheter-directed venous thrombolysis (PCDT) strategy that included AngioJet rheolytic thrombectomy. METHODS: In the Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis multicenter randomized trial, physicians at 33 sites designated AngioJet as their preferred device for PCDT. In these sites, 364 patients with acute proximal lower-extremity deep vein thrombosis (DVT) were randomized to a strategy of PCDT that incorporated either AngioJet along with anticoagulation or anticoagulation alone. Relief from presenting DVT symptoms was evaluated over 30 days of follow-up. Postthrombotic syndrome (PTS), quality of life (QOL), recurrent venous thromboembolism (VTE), and safety were evaluated over 24 months of follow-up. RESULTS: Within 30 days, AngioJet-PCDT led to a greater improvement in leg swelling (mean difference calf circumference 0.55 cm, P = .009), venous QOL (mean difference 6.5 Venous Insufficiency Epidemiologic and Economic Study [VEINES]-QOL points, P = .0073), and venous symptoms (mean difference 5.6 VEINES-symptoms points, P = .0134) than control, with differences most apparent in iliofemoral DVT. AngioJet-PCDT reduced PTS at 6 months (24% with AngioJet-PCDT vs 40% with control, P = .003) but did not influence PTS or QOL between 12 and 24 months. Major bleeding, pulmonary embolism, renal failure, and bradycardia were infrequent with AngioJet-PCDT (<2% each), but 24-month VTE recurrence may have been more frequent (13.9% with AngioJet-PCDT vs 6.8% with control, P = .03) CONCLUSIONS: In patients with acute proximal DVT, a treatment strategy that included first-line AngioJet-PCDT was reasonably safe and led to an improved symptom status and venous QOL at 1 month and reduced PTS at 6 months compared with anticoagulation alone. However, AngioJet-PCDT did not influence PTS or the QOL beyond 6 months and may have increased recurrent VTE.

Extracorporeal photopheresis to attenuate decline in lung function due to refractory obstructive allograft dysfunction.

BACKGROUND: This study was designed to prospectively evaluate the efficacy of extracorporeal photopheresis (ECP) to attenuate the rate of decline of FEV1 in lung transplant recipients with refractory bronchiolitis obliterans. Due to an observed higher than expected early mortality, a preliminary analysis was performed. STUDY DESIGN AND METHODS: Subjects from 10 lung transplant centres were assigned to ECP treatment or to observation based on spirometric criteria, with potential crossover for those under observation. The primary endpoint of this study was to assess response to ECP (i.e., greater than a 50% decrease in the rate of FEV1 decline) before and 6 months after initiation of ECP. Mortality was also evaluated 6 and 12 months after enrolment as a secondary endpoint. RESULTS: Of 44 enrolled subjects, 31 were assigned to ECP treatment while 13 were initially assigned to observation on a non-random basis using specific spirometric inclusion criteria (seven of the observation patients subsequently crossed over to receive ECP). Of evaluable patients, 95% of patients initially assigned to treatment responded to ECP with rates of FEV1 decline that were reduced by 93% in evaluable ECP-treated patients. Mortality rates (percentages) at 6 and 12 months after enrolment was 32% and 41%, respectively. The most common (92%) primary cause of death was respiratory or graft failure. Significantly (p = 0.002) higher rates of FEV1 decline were observed in the non-survivors (-212 ± 177 ml/month) when compared to the survivors (-95 ± 117 ml/month) 12 months after enrolment. In addition, 18 patients with bronchiolitis obliterans syndrome (BOS) diagnosis within 6 months of enrolment had lost 38% of their baseline lung function at BOS diagnosis and 50% of their lung function at enrolment. CONCLUSIONS: These analyses suggest that earlier detection and treatment of BOS should be considered to appreciate improved outcomes with ECP.

Performance of two clinical scales to assess quality of life in patients with post-thrombotic syndrome.

OBJECTIVE: We directly compared the Villalta scale and the Venous Clinical Severity Score (VCSS) to determine which of the two measures would be better at capturing clinically important cases of post-thrombotic syndrome (PTS) and PTS severity compared with patient-reported quality of life (QOL) scores. METHODS: We performed a secondary analysis of the ATTRACT (acute venous thrombosis: thrombus removal with adjunctive catheter-directed thrombolysis) trial study population. We calculated the correlations of the Villalta scores and VCSSs with QOL scores (short-form 36-item health survey [SF-36] physical component summary [PCS] and mental component summary [MCS]; and VEINES [venous insufficiency epidemiological and economic study]-QOL/symptom [VEINES-QOL/Sym] questionnaire) at each study visit (6, 12, 18, and 24 months of follow-up). The correlation of the random intercept (mean scores) and random slope (rate of change of the scores) among the Villalta scores, VCSS, and VEINES-QOL/Sym scores was assessed using a multivariate longitudinal model. RESULTS: The median correlation between Villalta scores and VCSSs was 0.72. The median correlation between the Villalta scores and VEINES-QOL and VEINES-Sym scores at all follow-up visits was -0.68 and -0.71, respectively. The median correlation between the Villalta scores and SF-36 PCS and MCS scores was -0.51 and -0.31, respectively. For the VCSSs, the median correlation with the VEINES-QOL and VEINES-Sym scores at all follow-up visits was -0.39 and -0.41, respectively. The median correlation between the VCSSs and SF-36 PCS and MCS scores was -0.32 and -0.13, respectively. The correlations between the random effects in the multivariate longitudinal models showed a similar pattern. The effect of covariate adjustment by age, sex, and body mass index was minor. CONCLUSIONS: The Villalta scores and VCSSs correlated strongly. The Villalta scale showed a substantially greater correlation with venous disease-specific and general QOL scores compared with the correlation with the VCSS. Our findings suggest that when a single scale is used to assess for clinically meaningful PTS, the Villalta scale will better capture the effects of PTS on patient-reported QOL.