A clinical trial of vena caval filters in the prevention of pulmonary embolism in patients with proximal deep-vein thrombosis. Prévention du Risque d'Embolie Pulmonaire par Interruption Cave Study Group

Right Ventricle Embolization of IVC Filter Fragments: An Incidental Finding

This case report describes a 52-year-old male patient, with the incidental finding of inferior vena cava filter (IVCF) fragments impacted into the right ventricle, secondary to IVCF fragmentation and subsequent embolization. While IVCFs are prescribed to prevent pulmonary embolizations when anticoagulation is either contraindicated, or has failed, IVCF embolizations to the heart represent an extremely rare, but potentially life-threatening complication. Of note, at the time of writing, the utility and effectiveness of IVCF are not fully established. Intracardiac embolizations of IVCF typically present with complications such as hypotension, cardiac tamponade, arrhythmias, ventricle perforation, bleeding, cardiac arrest, and death. To our knowledge, this is the first case report of an asymptomatic kidney transplant recipient found to have right ventricle embolizations of IVCF fragments through routine assessment. Additionally, this is also the first report of an asymptomatic patient who presented IVCF fragments embolized to the right ventricle and left gonadal vein in the same clinical setting.

Enhancing Routine Reporting of IVC Filters: An Interventionalist's Approach to Improving Patient Safety in an Underserved Urban Area

PurposeTo determine whether concurrent reporting and follow-up on diagnostic imaging could be used as an effective tool to raise IVC filter (IVCF) awareness in an underserved urban community. Methods: For this prospective study, radiologists at our institution flagged plain-film and cross-sectional imaging in which an IVCF was identified from October 2018 to October 2019. For consent, a phone survey was conducted to assess the patient's knowledge and understanding related to IVC filter placement. Key data points on the survey included patients' awareness of filter presence, placement date, location, difference between filters, satisfaction regarding peri-procedural education, and plan for filter removal. Patients desiring further information were scheduled for follow-up in the Vascular Interventional Radiology clinic. Results: 77 patients were identified with an IVC filter. 34 patients (15 males, 19 females; mean age 56y +/- 13.6 years) consented. 23.5% were unaware of their IVC filter. Of those aware, 61.5% were dissatisfied with their consultation/education during placement and 88% pursued further IR consultation indicating a desire to consult a clinician regarding their filter. During the study, 8 patients with IVCF (23.5%) were deemed no longer medically necessary; 6 underwent retrieval and 2 were pending at study conclusion. Conclusion: In underserved urban communities, patients with indwelling IVC filters may not have received appropriate follow-up instructions regarding filter retrieval or may be unaware they have one altogether. Diagnostic imaging is an effective tool to identify these patients, raise awareness, and improve retrieval of filters that are no longer indicated.

A review of venous thromboembolism for the hospitalist

Venous thromboembolism (VTE), consisting of both deep vein thrombosis (DVT) and pulmonary embolism (PE), is an extremely common condition both in the United States and worldwide. Not only is the diagnosis associated with significant morbidity and mortality for patients but it also imposes a deleterious financial burden on the US healthcare system. Diagnosis may be challenging due to variability in clinical presentation and requires a sequential workup including assessment of clinical pretest probability for VTE, D-dimer testing, and imaging. Following diagnosis, proper risk stratification is necessary to determine the appropriate treatment as well as the need for inpatient care. Elucidation of underlying major or minor risk factors at the time of diagnosis is essential as the presence of which may influence the duration of therapy. First-line treatment for most patients is anticoagulation with a direct oral anticoagulant (DOAC) for a minimum of 3-6 months. In multiple clinical trials, DOACs have proven to be non-inferior to vitamin K antagonists for the treatment of VTE with a lower risk of bleeding. Special consideration should be taken in the choice of agent and duration of treatment for patients who have underlying thrombophilias or malignancy and who are pregnant.

[Signs of high embolic risk in iliocaval floating thrombi]

OBJECTIVE

To analyze the ultrasound characteristics of iliocaval floating thrombi in patients with deep vein thrombosis regarding embolic risk.

MATERIAL AND METHODS

The study included 221 patients with deep vein thrombosis and iliocaval floating component. According to indications, all patients underwent implantation of infrarenal vena cava filter and received adequate anticoagulation. We analyzed the following parameters: length of floating clot, clot neck-to-stem ratio (minimum diameter of floating thrombus and diameter of clot attachment to occlusive thrombus), ratio of diameter of the clot neck to the widest part of the floating thrombus, as well as presence of large lateral inflow (internal iliac vein) near floating thrombus. Vena cava filter area was assessed regarding emboli. Ultrasound examinations were performed daily until primary endpoint (floating clot detachment or attachment to venous wall). The embolism group included 23 patients with clot detachment and cava filter embolism. The fixation group included 198 patients without cava filter embolism and floating thrombus attached to venous wall.

RESULTS

The risk of floating thrombus detachment increases by 2.49 times in patients with floating clot 70-79 mm [odds ratio (OR) 2.49; 95% confidence interval (CI) (1.2; 5.16); p=0.02] and 4.8 times in case of length >80 mm [OR 4.8; 95% CI (1.34; 17.19); p=0.03]. Minimum diameter of floating clot divided into diameter of clot attachment <30% increases the risk of detachment by 2.81 times [OR 2.81; 95% CI (1.44; 5.48); p=0.01]. Large lateral tributary near the neck of the floating thrombus increases the risk of detachment by 1.99 times [OR 1.99; 95% CI (1.1; 3.71); p=0.04].

CONCLUSION

There are certain risk factors in patients with deep vein thrombosis, iliocaval floating thrombus and no contraindications to anticoagulation (clot length >70 mm, minimum diameter of floating clot divided into diameter of clot attachment <30% and large lateral tributary near the neck of the thrombus). These ones should probably be classified as a group with extremely high risk of fatal pulmonary embolism and need for endovascular prophylaxis of venous thromboembolic complications (cava filter implantation) in addition to anticoagulation.

The Top 100 Most-Cited Articles in Venous Disease and Management

BACKGROUND

Advancements in the management of venous disease have been documented in scientific literature. We performed a bibliometric analysis using citations as an indication of impact to analyze the most influential articles on venous disease and treatment.

METHODS

A retrospective search of the Web of Science database was conducted in May 2023. Key search terms were queried to generate relevant articles. Articles were ranked on total number of citations and average number of citations per year. Metrics analyzed included top journals, impact factor, journal discipline, institution and country of publication, author degree and gender, number of publications per year, level of evidence, and article topic area.

RESULTS

The top 100 articles on venous disease were published between 1994 and 2020, with a total of 102,856 citations, average 1,028 citations/article, and mean of 70 citations/year. The most popular article was "Incidence of thrombotic complications of in critically ill Intensive Care Unit patients with COVID-19" with 3,482 citations in total. The most popular journals were New England Journal of Medicine (22 articles), Lancet (14 articles), and CHEST (13 articles), pertaining to management of deep venous thrombosis (DVT). The Journal of Vascular surgery had 2 influential articles, focused on management of chronic venous disease. Many articles were published in the United States (52), Canada (38), and Netherlands (25). Prolific authors were predominantly male (96%) and 59% were MDs versus 29% combined MD/PhD and 12% PhDs. Popular venous articles included guidelines/standards for DVT management (12%), epidemiology of venous thromboembolism (12%), and anticoagulation for DVT (12%). Specific venous thromboembolism risk factors within popular literature included prothrombotic genes, malignancy, pregnancy, trauma, and COVID-19. Articles on surgical interventions included inferior vena cava filter placement, catheter-directed thrombolysis, and risks of femoral and subclavian vein catheterization. Venous stenting and mechanical thrombectomy were not within the top articles.

CONCLUSIONS

Top-cited articles on venous disease emphasized management of DVT, followed by chronic venous disease, through the collaboration of multiple medical and surgical specialties. The largest number of citations in recent DVT literature was driven by COVID-19 complications.

Impact of Vein Wall Hyperelasticity and Blood Flow Turbulence on Hemodynamic Parameters in the Inferior Vena Cava with a Filter

Inferior vena cava (IVC) filters are vital in preventing pulmonary embolism (PE) by trapping large blood clots, especially in patients unsuitable for anticoagulation. In this study, the accuracy of two common simplifying assumptions in numerical studies of IVC filters-the rigid wall assumption and the laminar flow model-is examined, contrasting them with more realistic hyperelastic wall and turbulent flow models. Using fluid-structure interaction (FSI) and computational fluid dynamics (CFD) techniques, the investigation focuses on three hemodynamic parameters: time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), and relative residence time (RRT). Simulations are conducted with varying sizes of clots captured in the filter. The findings show that, in regions of high wall shear stress, the rigid wall model predicted higher TAWSS values, suggesting an increased disease risk compared to the hyperelastic model. However, the laminar and turbulent flow models did not show significant differences in TAWSS predictions. Conversely, in areas of low wall shear stress, the rigid wall model indicated lower OSI and RRT, hinting at a reduced risk compared to the hyperelastic model, with this discrepancy being more evident with larger clots. While the predictions for OSI and TAWSS were closely aligned for both laminar and turbulent flows, divergences in RRT predictions became apparent, especially in scenarios with very large clots.

Postmarketing Surveillance of Inferior Vena Cava Filters Among US Medicare Beneficiaries: The SAFE-IVC Study

Importance

Inferior vena cava filters (IVCFs) are commonly used to prevent pulmonary embolism in selected clinical scenarios, despite limited evidence to support their use. Current recommendations from professional societies and the US Food and Drug Administration endorse timely IVCF retrieval when clinically feasible. Current IVCF treatment patterns and outcomes remain poorly described.

Objectives

To evaluate temporal trends and practice patterns in IVCF insertion and retrieval among older US patients and report the incidence of periprocedural and long-term safety events of indwelling and retrieved IVCFs.

Design, Setting, and Participants

Prespecified, retrospective, observational cohort of Medicare Fee-for-Service (FFS) beneficiaries, leveraging 100% of samples of inpatient and outpatient claims data from January 1, 2013, to December 31, 2021.

Exposure

First-time IVCF insertion while insured by Medicare FFS.

Main Outcomes and Measures

The primary safety outcome was the composite of all-cause death, filter-related complications (eg, fracture, embolization), operating room visits following filter-related procedures, or new diagnosis of deep vein thrombosis (DVT). Events were considered periprocedural if they occurred within 30 days of IVCF insertion or retrieval and long-term if they occurred more than 30 days after.

Results

Among 270 866 patients with IVCFs placed during the study period (mean age, 75.1 years; 52.8% female), 64.9% were inserted for first-time venous thromboembolism (VTE), 26.3% for recurrent VTE, and 8.8% for VTE prophylaxis. Of these patients, 63.3% had major bleeds or trauma within 30 days of IVCF insertion. The volume of insertions decreased from 44 680 per year in 2013 to 19 501 per year in 2021. The cumulative incidence of retrieval was 15.3% at a median of 1.2 years and 16.8% at maximum follow-up of 9.0 years. Older age, more comorbidities, and Black race were associated with a decreased likelihood of retrieval, whereas placement at a large teaching hospital was associated with an increased likelihood of retrieval. The incidence of caval thrombosis and DVT among patients with nonretrieved IVCFs was 2.2% (95% CI, 2.1%-2.3%) and 9.2% (95% CI, 9.0%-9.3%), respectively. The majority (93.5%) of retrieval attempts were successful, with low incidence of 30-day complications (mortality, 0.7% [95% CI, 0.6%-0.8%]; filter-related complications, 1.4% [95% CI, 1.2%-1.5%]).

Conclusions and Relevance

In this large, US real-world analysis, IVCF insertion declined, yet retrievals remained low. Strategies to increase timely retrieval are needed, as nonretrieved IVCFs may have long-term complications.

Inferior Vena Cava Filter Retrieval: Simple to Complex

Retrievable inferior vena cava filters were designed to provide mechanical prophylaxis from pulmonary embolism with the intent for retrieval once no longer indicated, and have been utilized at a high rate since their introduction. Unfortunately, retrieval rates have historically lagged behind, in part due to significant rates of failed standard retrieval techniques for filters with prolonged dwell time. Refinement in advanced retrieval techniques has now allowed (in experienced centers) for safe removal of filters previously considered irretrievable. An individualized approach is necessary for each potential advanced filter retrieval to determine appropriate course of action. This review will emphasize complex filter retrieval techniques amidst a larger discussion of inferior vena cava filters and their management.

Inferior Vena Cava Filters: Adherence to Clinical Practice Guidelines Recommendations, Retrieval Rates, and Filter Complications in a Tertiary Hospital

The present study evaluated the adherence to guideline recommendations regarding the indication for inferior vena cava filter (IVCF) placement, retrieval rates, complications, thrombotic recurrences, and mortality. Patients in whom an IVCF was placed between 2015 and 2020 in a tertiary hospital were retrospectively included. We considered absolute indication of IVCF placement if all the guidelines evaluated agreed on the indication, relative indication if only some guidelines recommended it and without indication if none of the evaluated guidelines recommended it. From the 185 patients included; 47% had an absolute indication, 15% a relative indication, and 38% had no indication. Filter-associated complications and non-removal rates were 12.4% and 41%, respectively. Venous thromboembolism recurrence rate was 17.8%, being filter-associated complications (24.2 vs 9.8%, P = .02) and thrombosis of the inferior cava or iliac veins (12.1 vs 2.6%, P = .03) more frequent in this group. The mortality rate was 40%, with higher mortality risk in patients with co-existing cancer. Previous major bleeding, filter-associated complications, and mortality were associated with a major risk of non-removal. In conclusion, the adherence to guidelines regarding the indication of IVCF placement is still low and IVCF complications are not negligible. This fact is of special concern in the elderly, comorbid, and cancer patients.

Updated Trends in Inferior Vena Cava Filter Use by Indication in the United States After Food and Drug Administration Safety Warnings: A Decade Analysis From 2010 to 2019

BACKGROUND

Overall inferior vena cava filter (IVCF) utilization has decreased in the United States since the 2010 US Food and Drug Administration (FDA) safety communication. The FDA renewed this safety warning in 2014 with additional mandates on reporting IVCF-related adverse events. We evaluated the impact of the FDA recommendations on IVCF placements for different indications from 2010 to 2019 and further assessed utilization trends by region and hospital teaching status.

METHODS

Inferior vena cava filter placements between 2010 and 2019 were identified in the Nationwide Inpatient Sample database using the associated International Classification of Diseases, Ninth Revision, Clinical Modification, and Tenth Revision codes. Inferior vena cava filter placements were categorized by indication for venous thromboembolism (VTE) "treatment" in patients with VTE diagnosis and contraindication to anticoagulation and "prophylaxis" in patients without VTE. Generalized linear regression was used to analyze utilization trends.

RESULTS

A total of 823 717 IVCFs were placed over the study period, of which 644 663 (78.3%) were for VTE treatment and 179 054 (21.7%) were for prophylaxis indications. The median age for both categories of patients was 68 years. The total number of IVCFs placed for all indications decreased from 129 616 in 2010 to 58 465 in 2019, with an aggregate decline rate of -8.4%. The decline rate was higher between 2014 and 2019 than between 2010 and 2014 (-11.6% vs -7.2%). From 2010 to 2019, IVCF placement for VTE treatment and prophylaxis trended downward at rates of -7.9% and -10.2%, respectively. Urban nonteaching hospitals saw the highest decline for both VTE treatment (-17.2%) and prophylactic indications (-18.0%). Hospitals located in the Northeast region had the highest decline rates for VTE treatment (-10.3%) and prophylactic indications (-12.5%).

CONCLUSION

The higher decline rate in IVCF placements between 2014 and 2019 compared with 2010 and 2014 suggests an additional impact of the renewed 2014 FDA safety indications on national IVCF utilization. Variations in IVCF use for VTE treatment and prophylactic indications existed across hospital teaching types, locations, and regions.

CLINICAL IMPACT

Inferior vena cava filters (IVCF) are associated with medical complications. The 2010 and 2014 FDA safety warnings appeared to have synergistically contributed to a significant decline in IVCF utilization rates from 2010 - 2019 in the US. IVC filter placements in patients without venous thromboembolism (VTE) declined at a higher rate than VTE. However, IVCF utilization varied across hospitals and geographical locations, likely due to the absence of universally accepted clinical guidelines on IVCF indications and use. Harmonization of IVCF placement guidelines is needed to standardize clinical practice, thereby reducing the observed regional and hospital variations and potential IVC filter overutilization.

Epidemiology of the use of inferior vena cava filters in Brazil between 2008 and 2019

OBJECTIVES

The primary objective was to study the totality of inferior vena cava filter placements and their temporal and geographic distribution in the Brazilian Public Health System, which insures more than 160 million Brazilians. The secondary objective was to analyze in-hospital mortality after filter placement and deaths due to pulmonary embolism.

METHODS

Public and open data on in-hospital mortality due to pulmonary embolism and on rates of inferior vena cava filters placement, its associated diagnosis, and in-hospital mortality in Brazilian public hospitals between January 2008 and December 2019 were extracted from Ministry of Health databases.

RESULTS

A total of 9108 inferior vena cava filters were placed, 98.18% of which was therapeutic. We observed a significant increase in the use of these devices over the years, from 508 inferior vena cava filters placed in 2008 to 965 in 2019. In-hospital mortality rate in patients who received inferior vena cava filters was 6.21%, stable over time, and 96.64% of causes of these causes were attributed to venous thromboembolism. The in-hospital mortality rate due to pulmonary embolism, regardless of the placement of vena cava filters, has increased significantly.

CONCLUSION

We observed a low but increasing rate of inferior vena cava filter placements in Brazil between 2008 and 2019, most indications were therapeutic. Our findings were heterogeneous across Brazilian regions and contrasted to those observed in the USA, which is likely due to cultural and socioeconomic factors.

Inferior Vena Cava Filter in Cancer-Associated Thrombosis: A Vade Mecum for the Treating Physicians: A Narrative Review

Cancer is a remarkable prothrombotic disease, and cancer-associated thrombosis acts as a dreadful omen for poor prognosis. The cornerstone of venous thromboembolism therapy is anticoagulation; however, in patients with venous thromboembolism who are not suitable for anticoagulation (contraindication, failure, or complication), the inferior vena cava filter appears a valuable option in the therapeutic arsenal. The recently heightened trend of steady rise in filter placement mirrors the spread of retrievable devices, together with improvements in physicians' insertion ability, medico-legal issue, and novel and fewer thrombogenic materials. Nevertheless, the exact role of the inferior vena cava filter in cancer has yet to be endorsed due to a dearth of robust evidence. Indeed, data that support the inferior vena cava filter are weak and even controversial, resulting in discrepancies in the interpretation and application of guidelines in daily practice. In this narrative review, we aim at clarifying the state of the art on inferior vena cava filter use in malignancies. Furthermore, we provide a feasible, conclusive 4-step algorithm for the treating physicians in order to offer a practical strategy to successfully employ the inferior vena cava filter as a priceless device in the current armamentarium against cancer.

Duration of anticoagulation of venous thromboembolism

Venous thromboembolism (VTE) is a common, serious condition that requires anticoagulation for at least three months to prevent recurrence and long-term complications. After this initial period, the decision to continue or stop anticoagulation depends on the balance between the risk of recurrent VTE and the risk of bleeding. Established guidelines suggest short-term anticoagulation for VTE caused by transient factors and indefinite anticoagulation for recurrent or cancer-associated VTE. However, for a first unprovoked VTE, decision-making remains challenging. Current predictive scores for recurrence and bleeding are not sufficiently reliable, and the safety and efficacy of reduced-dose anticoagulation remain unclear. In the future, precision and patient-centred medicine may improve treatment decisions in this area.

Placing two inferior vena cava filters for the bail-out management of opening failure of an inferior vena cava filter

A 93-year-old man with a femoral fracture was admitted to the emergency department. The patient presented with severe hypoxemia and shock. Enhanced computed tomography confirmed deep venous thrombosis in the left leg and pulmonary embolism. Subsequently, an inferior vena cava filter (IVCF) was implanted. Although the IVCF was completely unsheathed for deployment, it remained fully folded and did not open; it was not deployed or retrieved. A new IVCF was successfully placed in the same position. Acute treatment for the deep venous thrombosis and further pulmonary embolism was achieved.

Vascular complications of tibial exostosis: A rare case of popliteal vein deep venous thrombosis

INTRODUCTION AND IMPORTANCE

Tibial exostosis (osteochondroma) represents a prevalent benign bone tumor typically identified in young adults. Uncommonly, vascular complications can emerge, encompassing vessel perforation, thrombosis and arterial thromboembolic events. Rare instances of popliteal vein thrombosis resulting from tibial osteochondroma have been documented.

CASE PRESENTATION

We report a rare case of a 25-year-old patient who presented with a red and swollen leg, and the diagnosis of deep venous thrombosis (DVT) of the left popliteal vein was established. The patient also exhibited a painless, hard swelling in the popliteal fossa. Radiography revealed an exostosis on the posterior aspect of the proximal tibia. An angioscan demonstrated close relations with the popliteal vessels, leading to venous compression. The patient underwent resection through a posterior knee approach. Histopathological analysis of the exostosis ruled out malignant transformation.

CLINICAL DISCUSSION

The discussion emphasizes the need for prompt diagnostic measures when signs indicate a vascular concern in a young patient, initiating with a radiograph followed by Doppler ultrasound and/or angiography to diagnose complications and precisely delineate their relationships with the tumor. Surgical intervention is underscored as urgent, particularly in cases involving arterial thrombosis, where immediate measures such as thrombectomy or bypass with a venous graft may be necessary.

CONCLUSION

Vascular complications associated with bone exostoses are rare but require prompt surgical treatment. However, it should prompt the performance of an angioscan in the presence of any abnormalities during clinical examination or an appearance raising concerns about potential vascular conflict.

Inferior vena cava filters: Concept review and summary of current guidelines

Anticoagulation is the first-line approach in the prevention and treatment of pulmonary embolism. In some instances, however, anticoagulation fails, or cannot be administered due to a high risk of bleeding. Inferior vena cava filters are metal alloy devices that mechanically trap emboli from the deep leg veins halting their transit to the pulmonary circulation, thus providing a mechanical alternative to anticoagulation in such conditions. The Greenfield filter was developed in 1973 and was later perfected to a model that could be inserted percutaneously. Since then, this model has been the reference standard. The current class I indication for this device includes absolute contraindication to anticoagulants in the presence of acute thromboembolism and recurrent thromboembolism despite adequate therapy. Additional indications have been more recently proposed, due to the development of removable filters and of progressively less invasive techniques. Although the use of inferior vena cava filters has solid theoretical advantages, clinical efficacy and adverse event profile are still unclear. This review analyzes the most important studies related to such devices, open issues, and current guideline recommendations.

Appropriateness guidelines for inferior vena cava filter utilization: A contemporary review

Concern regarding the exponential increase in optional utilization of inferior vena cava filters (IVCFs) in the early 2000s with a persistent low retrieval rate nationwide has resulted in increased scrutiny regarding clinical application of IVCFs. IVCFs are used in a variety of clinical scenarios, ranging from thromboembolic protection in patients with deep venous thrombosis and contraindication to anticoagulation to prophylactic deployment in multitrauma and critically ill patients. Evidence supporting IVCFs as mechanical thromboembolic protection in certain clinical scenarios has been established through evidenced-based guidelines. As an adjunct to evidence-based guidelines, appropriateness criteria to address specific clinical scenarios and facilitate clinical decision making when considering placement of an IVCF have been developed. In this review, current evidence-based and appropriateness guidelines are summarized.

Inferior Vena Cava Filters: An Overview

For patients with existing venous thromboembolisms (VTEs), anticoagulation remains the standard of care recommended across multiple professional organizations. However, for patients who developed a deep venous thrombosis (DVT) and/or a pulmonary embolism and cannot tolerate anticoagulation, inferior vena cava (IVC) filters must be considered among other alternative treatments. Although placement of a filter is considered a low-risk intervention, there are important factors and techniques that surgeons and interventionalists should be aware of and prepared to discuss. This overview covers the basics regarding the history of filters, indications for placement, associated risks, and techniques for difficult removal.

Safety and Outcomes of Inferior Vena Cava Filter Placement in Oncology Patients: A Single-Centre Experience

The risk of venous thromboembolism (VTE) in the oncology population is significantly higher than in non-cancer patients. Inferior vena cava (IVC) filters may, therefore, be an important part of VTE treatment. In this study, we address the outcomes of placing IVC filters in the oncology population. This single-centre, observational, retrospective study included 62 patients with active malignancy and acute VTE who underwent an IVC filter implantation due to contraindications to anticoagulation during the period 2012-2023. The control group consisted of 117 trauma patients. In both groups, an urgent surgical procedure requiring temporary cessation of anticoagulation was the most noted reason for IVC filter placement-76% in the oncology group vs. 100% in the non-oncology group (p < 0.001). No complications were reported during the IVC filter implantation procedures. There was no recurrence of pulmonary embolism or deep venous thrombosis in the oncology group after filter implantation. The rate of successful filter explantation, median time to retrieval, and abnormal findings during retrieval were not significantly different between both subgroups (64.3% vs. 76.5%, p = 0.334; 77 days vs. 84 days, p = 0.764; 61.5% vs. 54.2%, p = 0.672; respectively). The study showed that IVC filter placement is a safe and effective method of preventing PE in cancer patients with contraindications to anticoagulation. The complication rate following IVC filter implantation in cancer patients is low and similar to that in non-oncology patients.

Clinical Correlates of In-Hospital Mortality in Patients Undergoing Inferior Vena Cava Filter Placement for Acute Deep Vein Thrombosis

Background: It is reasonable to place an Inferior Vena Cava Filter (IVCF) when an acute deep vein thrombosis (DVT) of the lower limbs occurs in a patient with absolute contraindication to therapeutic anticoagulation. An additional potential reason for placing an IVCF is the need to stop therapeutic anticoagulation in a patient with acute DVT who must undergo urgent non-deferrable surgery. However, IVCFs are often used outside of such established indications and many authors argue about their actual utility, especially in terms of survival. In this retrospective study, we looked for clinical correlates of in-hospital mortality among patients who underwent IVCF placement, limiting our analysis to the cases for which a correct indication to IVCF placement existed. Methods: We retrospectively analyzed the electronic database of our University Hospital, searching for consecutive hospitalized patients who had acute DVT and underwent IVCF placement because of an established contraindication to therapeutic anticoagulation and/or because it was necessary to stop anticoagulation due to urgent surgery. The search covered the period between 1 January 2010 and 31 December 2020. Results: The search resulted in the identification of 168 individuals. An established contraindication to therapeutic anticoagulation was present in 116 patients (69.0%), while urgent non-deferrable surgery was the reason for IVCF placement in 52 patients (31.0%). A total of 24 patients (14.3%) died during the same hospital stay in which the IVCF was placed. Mortality rate was significantly higher in patients with a contraindication to anticoagulation than in patients who underwent IVCF placement because of urgent surgery (19.0% vs. 3.8%, OD 5.85 vs. 0.17). In-hospital mortality was also significantly higher among patients with chronic kidney disease and those who needed blood cell transfusion during hospitalization. Conclusions: This study provides novel information on clinical correlates of in-hospital mortality among patients with acute DVT who undergo IVCF. Prospective observational studies are needed to substantiate these findings.

Recurrent Deep Vein Thrombosis (DVT) and Inferior Vena Cava (IVC) Filter: Should a Computed Tomography (CT) Venogram and Inferior Vena Cavagram Be the Standard of Care?

A pulmonary embolism (PE) is a life-threatening complication of deep vein thrombosis (DVT). Although timely anticoagulation is the first-line treatment for DVT, an inferior vena cava (IVC) filter can be considered when anticoagulation is contraindicated. Unfortunately, IVC filters come with complications of their own, including thrombus formation in or around the filter. An 89-year-old man with a past medical history of coronary artery disease, congestive heart failure, chronic obstructive pulmonary disease, and prior DVT status post IVC filter implantation five years ago in 2018 presented with hypotension, dizziness, and syncope. Computed tomography angiography (CTA) of the chest showed bilateral PEs. Venous Doppler ultrasound of the bilateral lower extremities was negative for DVT. CT venogram was performed; however, the contrast filling was suboptimal and as such, a venous thrombosis could not be ruled out. Therefore, an inferior vena cavagram was performed through the right common femoral vein and confirmed a large thrombus positioned cephalad to the IVC filter. A thrombectomy was performed and the IVC filter was replaced given the patient was at high risk for venous thromboembolism recurrence and complications.  Although an IVC filter offers some protection from recurrent PEs, it does have risks and complications. As seen in our patient, the IVC filter can be a nidus for the formation of a thrombus which has the risk of dislodging. When evaluating a patient for the source of a PE, it is important to consider prior IVC implant and perform further workups, such as a CT venogram or an inferior vena cavagram, to evaluate for thrombus in or around the filter.

Percutaneous interventions for pulmonary embolism

Pulmonary embolism (PE) ranks as a leading cause of in-hospital mortality and the third most common cause of cardiovascular death. The spectrum of PE manifestations varies widely, making it difficult to determine the best treatment approach for specific patients. Conventional treatment options include anticoagulation, thrombolysis, or surgery, but emerging percutaneous interventional procedures are being investigated for their potential benefits in heterogeneous PE populations. These novel interventional techniques encompass catheter-directed thrombolysis, mechanical thrombectomy, and hybrid approaches combining different mechanisms. Furthermore, inferior vena cava filters are also available as an option for PE prevention. Such interventions may offer faster improvements in right ventricular function, as well as in pulmonary and systemic haemodynamics, in individual patients. Moreover, percutaneous treatment may be a valid alternative to traditional therapies in high bleeding risk patients and could potentially reduce the burden of mortality related to major bleeds, such as that of haemorrhagic strokes. Nevertheless, the safety and efficacy of these techniques compared to conservative therapies have not been conclusively established. This review offers a comprehensive evaluation of the current evidence for percutaneous interventions in PE and provides guidance for selecting appropriate patients and treatments. It serves as a valuable resource for future researchers and clinicians seeking to advance this field. Additionally, we explore future perspectives, proposing "percutaneous primary pulmonary intervention" as a potential paradigm shift in the field.

Venous Thromboembolism: Review of Clinical Challenges, Biology, Assessment, Treatment, and Modeling

Venous thromboembolism (VTE) is a massive clinical challenge, annually affecting millions of patients globally. VTE is a particularly consequential pathology, as incidence is correlated with extremely common risk factors, and a large cohort of patients experience recurrent VTE after initial intervention. Altered hemodynamics, hypercoagulability, and damaged vascular tissue cause deep-vein thrombosis and pulmonary embolism, the two permutations of VTE. Venous valves have been identified as likely locations for initial blood clot formation, but the exact pathway by which thrombosis occurs in this environment is not entirely clear. Several risk factors are known to increase the likelihood of VTE, particularly those that increase inflammation and coagulability, increase venous resistance, and damage the endothelial lining. While these risk factors are useful as predictive tools, VTE diagnosis prior to presentation of outward symptoms is difficult, chiefly due to challenges in successfully imaging deep-vein thrombi. Clinically, VTE can be managed by anticoagulants or mechanical intervention. Recently, direct oral anticoagulants and catheter-directed thrombolysis have emerged as leading tools in resolution of venous thrombosis. While a satisfactory VTE model has yet to be developed, recent strides have been made in advancing in silico models of venous hemodynamics, hemorheology, fluid-structure interaction, and clot growth. These models are often guided by imaging-informed boundary conditions or inspired by benchtop animal models. These gaps in knowledge are critical targets to address necessary improvements in prediction and diagnosis, clinical management, and VTE experimental and computational models.

Acute caval thrombosis leading to obstructive shock in the early post insertion period of an inferior vena cava filter: a case report and literature review

BACKGROUND

Obstructive shock is extremely rare in clinical practice and is caused by acute blood flow obstruction in the central vessels of either the systemic or pulmonary circulation. Utilizing inferior vena cava filters (IVCFs) to prevent pulmonary embolism (PE) is associated with some potential complications, such as inferior vena cava thrombosis (IVCT). Shock as a direct result of IVCT is rare. We present a case of obstructive shock secondary to extensive IVCT caused by inadequate anticoagulant therapy after the placement of an IVCF.

CASE PRESENTATION

A 63-year-old male patient with a traffic accident injury presented orthopaedic trauma and lower limb deep vein thrombosis (DVT). He experienced sudden and severe abdominal pain with hypotension, tachycardia, tachypnea, oliguria and peripheral oedema 5 days after IVCF placement and 3 days after cessation of anticoagulant therapy. Considering that empirical anti-shock treatment lasted for a while and the curative effect was poor, we finally recognized the affected vessels and focused on the reason for obstructive shock through imaging findings-inferior vena cava thrombosis and occlusion. The shock state immediately resolved after thrombus aspiration. The same type of shock occurred again 6 days later during transfer from the ICU to general wards and the same treatment was administered. The patient recovered smoothly in the later stage, and the postoperative follow-up at 1, 3, and 12 months showed good results.

CONCLUSION

This case alerts clinicians that it is crucial to ensure adequate anticoagulation therapy after IVCF placement, and when a patient presents with symptoms such as hypotension, tachycardia, and lower limb and scrotal oedema postoperatively, immediate consideration should be given to the possibility of obstructive shock, and prompt intervention should be based on the underlying cause.

Predictors of retrieval and long-term mortality in patients treated with inferior vena cava filters

OBJECTIVE

Inferior vena cava filters (VCFs) are a therapeutic resource for the treatment of patients with thromboembolic disease who have a contraindication to full-dose anticoagulation. In the present study, we report the retrieval rate and long-term mortality of patients receiving optional inferior VCFs and identify the predictors for retrieval and all-cause mortality during follow-up.

METHODS

We conducted a retrospective cohort study of 739 consecutive recipients of optional inferior VCFs from January 2002 to December 2021 in two hospitals. Different clinical characteristics and procedure-related variables were included in the analysis. The all-cause mortality rate and retrieval rate and the predictive factors were evaluated using multivariate analysis.

RESULTS

Of the 739 patients, 393 (53%) were women. The mean patient age was 69 ± 15 years. Of the patients, 67% presented with pulmonary thromboembolism and 43% with deep vein thrombosis (DVT). A contraindication to anticoagulation was present for nearly 90% of the patients, mainly (47%) related to the surgical procedure. In addition, 44% of the patients had active cancer. Follow-up data were available for 94% of the patients, with an average follow-up time of 6.08 ± 5.83 years. Long-term mortality was 53%. Cancer (odds ratio [OR], 3.60; 95% confidence interval [CI], 2.22-5.83), age (OR, 1.03; 95% CI, 1.08-1.42), and DVT (OR, 2.01; 95% CI, 1.08-1.42) were identified as independent predictors of mortality. The retrieval rate at follow-up was 33%. The predictors for retrieval included the indication of the filter related to a surgical procedure (OR, 4.85; 95% CI, 2.54-9.59), the absence of cancer (OR, 2.89; 95% CI, 1.45-5.75), and younger age (OR, 0.98; 95% CI, 0.97-0.99).

CONCLUSIONS

High long-term mortality was observed. The predictors of mortality were cancer, older age, and DVT. One third of the filters implanted were retrieved. The predictors for retrieval were a contraindication to surgery-related anticoagulation, the absence of cancer, and younger age.

Association of vena cava filters and catheter-directed thrombolysis for deep vein thrombosis with hospital readmissions

BACKGROUND

Acute deep vein thrombosis (DVT) affects >350,000 patients each year in the United States. Contemporary rehospitalization rates and predictors of acute DVT have not been well-characterized. We aimed to evaluate the all-cause 30-day readmission rate and its association with catheter-directed thrombolysis and vena cava filters in patients with proximal and caval DVT.

METHODS

Patients with an index hospitalization for acute proximal lower extremity DVT were evaluated for unplanned readmission rates at 30 days using the Nationwide Readmission Database from 2016 to 2017. We used Cox proportional hazard model to determine the predictors of 30-day readmissions and their association with inferior vena cava (IVC) filter and CDT use.

RESULTS

We identified 58,306 adult patients with an index hospitalization for acute proximal DVT. The unplanned 30-day rehospitalization rate was 14.7% (95% confidence interval [CI], 14.5-15.0%). There were 4995 patients (10.0%) who underwent CDT and 6085 (12.2%) who underwent IVC filter placement. In multivariable analysis, only CDT was associated with a lower hazard for rehospitalization (hazard ratio [HR], 0.77; 95% CI, 0.71-0.84; P < .001), whereas IVC filter placement (HR, 1.26; 95% CI, 1.19-1.34; P < .001), Charlson Comorbidity Index of >3 (HR, 1.47; 95% CI, 1.38-1.56; P < .001), malignancy (HR, 1.45; 95% CI, 1.34-1.57; P < .001), and length of stay >5 days (HR, 1.39; 95% CI, 1.33-1.46; P < .001), and acute kidney injury (HR, 1.18; 95% CI, 1.11-1.25; P < .001) were associated with higher readmission rates.

CONCLUSIONS

The 30-day unplanned rehospitalization rate continues to be high in patients with acute proximal DVT. CDT was associated with lower rehospitalization rates, whereas IVC filter placement was associated with increased rehospitalization rates.

Extensive Iliocaval Deep Vein Thrombosis Provoked by Coronavirus Disease 2019 (COVID-19) in the Setting of an Inferior Vena Cava Filter

Thrombotic events are well-known complications of coronavirus disease 2019 (COVID-19). Inferior vena cava filters (IVCF) are devices used to prevent pulmonary embolism (PE) and also increase the risk of thrombotic complications. Here, we describe the case of a 38-year-old female with extensive bilateral lower extremity deep vein thrombosis (DVT) and thrombosis of the infrarenal inferior vena cava (IVC) in the setting of an IVCF and symptomatic COVID-19. The IVCF had been placed a few months prior for a left femoral DVT and PE after spinal surgery. This patient was treated with pharmacomechanical thrombectomy and ultrasound-assisted thrombolysis followed by angioplasty and anticoagulation. The IVCF was retrieved after confirming there was no residual DVT when the patient recovered from COVID-19 infection. This case of a rare combination of IVCF-related thrombosis secondary to COVID-19 highlights the potential pitfalls of IVCF in this situation.

Detecting and Characterizing Inferior Vena Cava Filters on Abdominal Computed Tomography with Data-Driven Computational Frameworks

Two data-driven algorithms were developed for detecting and characterizing Inferior Vena Cava (IVC) filters on abdominal computed tomography to assist healthcare providers with the appropriate management of these devices to decrease complications: one based on 2-dimensional data and transfer learning (2D + TL) and an augmented version of the same algorithm which accounts for the 3-dimensional information leveraging recurrent convolutional neural networks (3D + RCNN). The study contains 2048 abdominal computed tomography studies obtained from 439 patients who underwent IVC filter placement during the 10-year period from January 1st, 2009, to January 1st, 2019. Among these, 399 patients had retrievable filters, and 40 had non-retrievable filter types. The reference annotations for the filter location were obtained through a custom-developed interface. The ground truth annotations for the filter types were determined based on the electronic medical record and physician review of imaging. The initial stage of the framework returns a list of locations containing metallic objects based on the density of the structure. The second stage processes the candidate locations and determines which one contains an IVC filter. The final stage of the pipeline classifies the filter types as retrievable vs. non-retrievable. The computational models are trained using Tensorflow Keras API on an Nvidia Quadro GV100 system. We utilized a fine-tuning supervised training strategy to conduct our experiments. We find that the system achieves high sensitivity on detecting the filter locations with a high confidence value. The 2D + TL model achieved a sensitivity of 0.911 and a precision of 0.804, and the 3D + RCNN model achieved a sensitivity of 0.923 and a precision of 0.853 for filter detection. The system confidence for the IVC location predictions is high: 0.993 for 2D + TL and 0.996 for 3D + RCNN. The filter type prediction component of the system achieved 0.945 sensitivity, 0.882 specificity, and 0.97 AUC score with 2D + TL and 0. 940 sensitivity, 0.927 specificity, and 0.975 AUC score with 3D + RCNN. With the intent to create tools to improve patient outcomes, this study describes the initial phase of a computational framework to support healthcare providers in detecting patients with retained IVC filters, so an individualized decision can be made to remove these devices when appropriate, to decrease complications. To our knowledge, this is the first study that curates abdominal computed tomography (CT) scans and presents an algorithm for automated detection and characterization of IVC filters.

Guideline Compliance and Indications for Inferior Vena Cava Filter Placement at a Quaternary Care Medical Center

PURPOSE

This study investigated physician compliance with indications for inferior vena cava (IVC) filter placement according to the 2012 American College of Chest Physicians (ACCP) and the 2011 Society of Interventional Radiology (SIR) guidelines.

MATERIALS AND METHODS

A retrospective medical record review of 231 retrievable IVC filters placed between August 15, 2016, and December 28, 2017, at a large urban academic medical center. Guideline compliance to the 2012 ACCP and the 2011 SIR guidelines, and indications for IVC filter placements were assessed through an adjudication protocol. Filter retrieval and complication rates were also examined.

RESULTS

Compliance to guidelines was low (60.2% for ACCP; 74.0% for SIR), especially for non-intensive care unit (ICU) patients (ICU 74.6% vs non-ICU 54.8%, p=0.007 for ACCP; ICU 82.5% vs non-ICU 70.8%, p=0.092 for SIR). After adjudication, 8.2% (19/231) of filters were considered non-indicated but reasonable, 17.7% (41/231) non-indicated and unreasonable, and 13.9% (32/231) SIR-indicated but not ACCP-indicated. The most common indication was venous thromboembolism with contraindication to anticoagulation. The most common reasons for non-compliance were distal deep venous thrombosis with contraindication to anticoagulation (19/60, 31.6%) and clot burden (19/60, 31.6%). One-year filter retrieval and 90-day complication rates were 32.0% (74/231) and 6.1% (14/231), respectively.

CONCLUSION

Compliance to established guidelines was low. Reasons for non-compliance included limitations or discrepancies in guidelines, as well as non-evidence-based filter placements.

CLINICAL IMPACT

Despite increasing utilization of inferior vena cava (IVC) filters, guideline compliance for IVC filter placement among providers is unclear. The results of this study indicate that physician compliance to established guidelines is poor, especially in non-intensive-care-unit patients. Noncompliance stems from non-evidence-based filter placement as well as differences and limitations in guidelines. Avoiding non-indicated IVC filter placement and consolidation of guidelines may significantly improve guideline compliance. The critical insights gained from this study can help promote judicious use of IVC filters and highlight the role of venous thromboembolism experts in navigating complex cases and nuances of guidelines.

The use of pre-operative Inferior Vena Cava filters for thromboprophylaxis in ultra-high-risk patients undergoing total hip and knee arthroplasty: a systematic review and narrative analysis

PURPOSE

Patients undergoing total hip (THA) or knee (TKA) arthroplasty are at high risk of venous thromboembolism (VTE). As the number performed annually increases, the population at risk of fatal pulmonary embolism (PE) also grows. Ultra-high-risk arthroplasty patients (UHRAPs) include those with additional comorbidities, or a history of VTE, for many of whom routine prophylaxis will previously have failed. Pre-operative insertion of Inferior Vena Cava filters (IVCFs) has been recommended for thromboprophylaxis in UHRAPs, and this review was performed to establish their results.

METHODS

A systematic search of MEDLINE and Embase databases was performed for studies reporting the use of Inferior Vena Cava filters in hip and knee arthroplasty patients.

RESULTS

Ten studies met the inclusion criteria, containing 718 IVCFs in Orthopaedic patients, 343 of which were permanent (47.8%), 369 potentially retrievable (51.4%), 5 absorbable (0.6%) and one of unknown design (0.1%). Patient age averaged 64.7yrs (17-95) and 56% were female. Pre-operatively, 415 prophylactic IVCFs were inserted in 409 UHRAPs, undergoing a total of 438 total joint arthroplasties (TJA). There were 11 cases of PE in the entire series (1.5%) only one of which was fatal (0.01%), with four non-fatal PE in the UHRAP group (0.96%). Removal was attempted for 283 of the retrievable filters (76.7%) and was successful in 280 (98.9%).

CONCLUSION

The use of IVCFs eliminated fatal PE in UHRAPs, but larger, high-quality studies, with standardised reporting, are still required to determine their absolute indications for use, complication profile, efficacy and optimum design.

A Review of Healthcare Disparities Relevant to Interventional Radiology

Racial, ethnic, and gender disparities have received focused attention recently, as they became more visible in the COVID era. We continue to learn more about how healthcare disparities manifest for our patients and, more broadly, the structural underpinnings that result in predictable outcomes gaps. This review summarizes what we know about disparities relevant to interventional radiologists. The prevalence and magnitude of disparities are quantified and discussed where relevant. Specific examples are provided to demonstrate how factors like gender, ethnicity, social status, geography, etc. interact to create inequities in the delivery of interventional radiology (IR) care. Understanding and addressing health disparities in IR is crucial for improving real-world patient outcomes and reducing the economic burden associated with ineffective and low-value care. Finally, the importance of intentional mentorship, outreach, education, and equitable distribution of high-quality healthcare to mitigate these disparities and promote health equity in interventional radiology is discussed.

Do Prophylactic Inferior Vena Cava Filters Affect the Rates of Venous Thromboembolism and Pulmonary Embolism in Patients Undergoing Major Spine Surgery?

STUDY DESIGN

Retrospective Analysis.

BACKGROUND

Venous thromboembolism (VTE) represents a significant cause of morbidity and mortality in major spine surgery. Placement of prophylactic inferior vena cava filters (IVCF) in patients undergoing major spine surgery was previously adopted at our institution. This study reports our experience and compares VTE rates between patients with and without preoperative IVCF placement.

METHODS

A Retrospective comparative study was conducted on adult patients who underwent IVCF placement and those who did not prior to their spinal fusion procedure, between 2013 and 2016. Thoracolumbar fusions (anterior and/or posterior) of 7 or more levels, spinal osteotomies, and a minimum of a 3-month follow-up were included. Traumatic, oncologic, and cervical pathology were excluded. Primary outcomes measured included the incidence of overall VTE (DVT/PE), death, IVCF related complications, and IVCF retrieval.

RESULTS

386 patients who underwent major spine surgery, 258 met the eligibility criteria. Of those patients, 105 patients (40.7%) had prophylactic IVCF placement. All patients had postoperative SCDs and chemoprophylaxis. The presence of an IVCF was associated with an increased rate of overall VTE (14.3% vs 6.5%, P ≤ .05) and DVT episodes (8.6% vs 2.6%, P = .04). The rate of PE for the IVCF group and non-IVCF group was 8.6% and 4.6%, respectively, which was not statistically significant (P = .32). The all-cause mortality rate overall of 2.3% was statistically similar between both groups (P = 1.0). The IVCF group had higher rates of hematoma/seroma vs the non-IVCF group (12.4% vs 3.9%, P ≤ .05). 99 IVCFs were retrievable designs, and 85% were successfully retrieved. Overall IVCF-related complication rate was 11%.

CONCLUSIONS

No statistical difference in PE or mortality rates existed between the IVCF and the control group. Patients with IVCF placement experienced approximately twice the rate of VTE and three times the rate of DVT compared to those without IVCF. The IVCF-related complication rate was 11%. Based on the results of this study, the authors recommend against the routine use of prophylactic IVCFs in adults undergoing major spine surgery.

LEVEL OF EVIDENCE

III.

Large Thrombus Entrapped in a Patent Foramen Ovale during Inferior Vena Cava Filter Protection for Venous Thromboembolism

Background. A large thrombus entrapped in the patent foramen ovale (PFO) is an extremely rare condition. Moreover, it is considered even rarer after temporary inferior vena cava filter (TIVCF) placement for the prevention of fatal pulmonary embolism due to venous thromboembolism (VTE). Case Report. A 58-year-old man presented with syncope following chest pain and dyspnea due to PE exacerbation during TIVCF protection, which then led to cardiogenic shock. Echocardiography revealed a large thrombus entrapped in the PFO, and computed tomography (CT) showed a bilateral pulmonary artery embolism. The patient was treated with open surgical embolectomy for a pulmonary artery thrombus and PFO thrombus with simultaneous closure of the PFO. The patient's postoperative course was uneventful. Results and Conclusion. Surgical embolectomy was useful with respect to the feasibility of resection of both intracardiac thrombus and pulmonary artery thrombus performed simultaneously, contributing to the prevention of systemic embolisms, and echocardiography plays an important role for early diagnosis.

Efficacy and safety of vena cava filters in preventing pulmonary embolism: A systematic review and meta-analysis

OBJECTIVES

To assess the treatment effectiveness of inferior vena cava filters (IVCF) versus non-IVCF for patients undergoing varies conditions.

METHODS

We systematically searched the databases to identify eligible RCTs from their inception up to 9/20/2020. The primary endpoint was pulmonary embolism (PE), while the secondary endpoints included deep-vein thrombosis (DVT), major bleeding, and all-cause mortality. The RRs with 95% CIs were applied as effect estimates for the treatment effectiveness of IVCF versus non-IVCF and calculated by using the random-effects model.

RESULTS

1,137 patients of 5 RCTs were enrolled. There were no significant differences between IVCF and non-IVCF for the risk of PE, major bleeding, and all-cause mortality, while the risk of DVT was significantly increased for patients treated with IVCF.

CONCLUSIONS

The use of IVCF did not yield any benefits on PE, major bleeding, and all-cause mortality risk for patients undergoing various conditions, while the risk of DVT was significantly increased for patients treated with IVCF.

Denali Inferior Vena Cava Filter Retrieval: Complications and Success Rates

PURPOSE

The present study was to evaluate the outcomes of Denali filter retrieval.

MATERIALS AND METHODS

We retrospectively reviewed 143 patients who received Denali filter insertion from September 2015 to April 2020. Ninety-seven patients who required removal of the filters were include in this study. Filters were retrieved with either standard or advanced techniques. Venography before and after retrieval was obtained to evaluate technical success, complications and duration of filter insertion.

RESULTS

All 97 filters were retrieved successfully without complications. Ninety-two (94.8%) were retrieved with standard technique and 5 filters (5.2%) required the advanced technique. There were two cases with a filter angle greater than 15 degrees. Inferior vena cava penetration was shown in 17 patients (17.5%) on venography but was not associated with contrast media extravasation after filter removal.

CONCLUSION

The Denali filter showed a high rate of successful retrieval without complications. This study adds value to previous studies and trials showing that the Denali filter is a reliable and safe filter that can potentially improve retrieval rates, with increasing use of this device.

Prevention, Diagnostics and Treatment of Deep Vein Thrombosis. Russian Experts Consensus

The guidelines are developed in accordance with the requirements of the Ministry of Health of the Russian Federation by the all-Russian public organization «Association of Phlebologists of Russia» with participation of the Association of Cardiovascular Surgeons of Russia, the Russian Society of Surgeons, the Russian Society of Angiologists and Vascular Surgeons, the Association of Traumatologists and Orthopedists of Russia, the Association of Oncologists of Russia, the Russian Society of Clinical Oncology, Russian Society of Oncohematologists, Russian Society of Cardiology, Russian Society of Obstetricians and Gynecologists.

Prophylactic Inferior Vena Cava Filters for Venous Thromboembolism in Adults With Trauma: An Updated Systematic Review and Meta-Analysis

Background: Trauma is an independent risk factor for venous thromboembolism (VTE). Due to contraindications or delay in starting pharmacological prophylaxis among trauma patients with a high risk of bleeding, the inferior vena cava (IVC) filter has been utilized as alternative prevention for pulmonary embolism (PE). Albeit, its clinical efficacy has remained uncertain. Therefore, we performed an updated systematic review and meta-analysis on the effectiveness and safety of prophylactic IVC filters in severely injured patients. Methods: Three databases (MEDLINE, EMBASE, and Cochrane) were searched from August 1, 2012, to October 27, 2021. Independent reviewers performed data extraction and quality assessment. Relative risk (RR) at 95% confidence interval (CI) pooled in a randomized meta-analysis. A parallel clinical practice guideline committee assessed the certainty of evidence using the GRADE approach. The outcomes of interest included VTE, PE, deep venous thrombosis, mortality, and IVC filter complications. Results: We included 10 controlled studies (47 140 patients), of which 3 studies (310 patients) were randomized controlled trials (RCTs) and 7 were observational studies (46 830 patients). IVC filters demonstrated no significant reduction in PE and fatal PE (RR, 0.27; 95% CI, 0.06-1.28 and RR, 0.32; 95% CI, 0.01-7.84, respectively) by pooling RCTs with low certainty. However, it demonstrated a significant reduction in the risk of PE and fatal PE (RR, 0.25; 95% CI, 0.12-0.55 and RR, 0.09; 95% CI, 0.011-0.81, respectively) by pooling observational studies with very low certainty. IVC filter did not improve mortality in both RCTs and observational studies (RR, 1.44; 95% CI, 0.86-2.43 and RR, 0.63; 95% CI, 0.3-1.31, respectively). Conclusion: In trauma patients, moderate risk reduction of PE and fatal PE was demonstrated among observational data but not RCTs. The desirable effect is not robust to outweigh the undesirable effects associated with IVC filter complications. Current evidence suggests against routinely using prophylactic IVC filters.

Perioperative management of acetabular and pelvic fractures: evidence-based recommendations

PURPOSE

The American Academy of Orthopaedic Surgeons does not currently provide clinical practice guidelines for management of PAF. Accordingly, this article aims to review and consolidate the relevant historical and recent literature in important topics pertaining to perioperative management of PAF.

METHODS

A thorough literature review using PubMed, Cochrane and Embase databases was performed to assess preoperative, intraoperative and postoperative management of PAF fracture. Topics reviewed included: time from injury to definitive fixation, the role of inferior vena cava filters (IVCF), tranexamic acid (TXA) use, intraopoperative cell salvage, incisional negative pressure wound therapy (NPWT), intraoperative antibiotic powder use, heterotopic ossification prophylaxis, and pre- and postoperative venous thromboembolism (VTE) prophylaxis.

RESULTS

A total of 126 articles pertaining to the preoperative, intraoperative and postoperative management of PAF were reviewed. Articles reviewed by topic include 13 articles pertaining to time to fixation, 23 on IVCF use, 14 on VTE prophylaxis, 20 on TXA use, 10 on cell salvage, 10 on iNPWT 14 on intraoperative antibiotic powder and 20 on HO prophylaxis. An additional eight articles were reviewed to describe background information. Five articles provided information for two or more treatment modalities and were therefore included in multiple categories when tabulating the number of articles reviewed per topic.

CONCLUSION

The literature supports the use of radiation therapy for HO prophylaxis, early (< 5 days from injury) surgical intervention and the routine use of intraoperative TXA. The literature does not support the routine use of iNPWT or IVCF. There is inadequate information to make a recommendation regarding the use of cell salvage and wound infiltration with antibiotic powder. While the routine use of chemical VTE prophylaxis is recommended, there is insufficient evidence to recommend the optimal agent and duration of therapy.

Endovascular Venous Interventions - A State-of-the-Art Review

Venous vascular diseases are an important clinical entity estimated to affect several million people worldwide. Deep vein thrombosis (DVT) is a common venous disease with a population variable prevalence of 122 to 160 persons per 100,000 per year, whereas pulmonary embolism (PE) affects up to 60 to 70 per 100 000 and carries much higher mortality. Chronic venous diseases, which cause symptoms like leg swelling, heaviness, pain, and discomfort, are most prevalent in the elderly and significantly impact their quality of life. Some estimate that chronic vascular diseases account for up to 2% of healthcare budgets in Western countries. Treating venous vascular disease includes using systemic anticoagulation and interventional therapies in some patient subsets. In this comprehensive review, we discuss endovascular treatment modalities in the management of venous vascular diseases.

Clinical and imaging outcomes of OptionELITE vena cava filter placement procedures

OBJECTIVE

We sought to determine the clinical and imaging outcomes after placement of the OptionELITE inferior vena cava (IVC) filter (Argon Medical Devices, Plano, TX).

METHODS

The clinical characteristics and imaging findings of patients who had undergone OptionELITE filter placement at six affiliated hospitals between January 1, 2013 and April 19, 2019, were analyzed. Data were obtained from the Radiology Information System, imaging database, and electronic medical records. The patients were followed up until 1 month after filter removal, death, or the first clinic visit and imaging study after June 1, 2019.

RESULTS

A total of 603 filter placement procedures in 594 patients were evaluated. Of the 603 procedures, 602 were technically successful (99.8%). Of the 594 patients, 356 had presented with acute pulmonary embolism and/or deep vein thrombosis. A total of 189 filters were retrieved from the 191 patients for whom retrieval had been attempted at 4.3 ± 6.3 months (median, 2.5 months) after placement. The 414 filters without removal procedures had been followed up for 14.8 ± 17.7 months (median, 6.9 months). During the follow-up period, 57 patients (9.5%) had developed new or worsening deep vein thrombosis caudal to the filter and 19 (3.2%) had experienced new symptomatic nonfatal pulmonary embolism after filter placement. One filter had migrated and fractured, and another filter had fractured and a strut was lost. Perforation was demonstrated equivocally in 12 (3%) and definitely in 17 (4.3%) of 399 patients with adequate imaging studies available, with penetration into surrounding structures in 13 patients (3.3%). Of 332 patients with adequate imaging studies, 12 (3.6%) had developed substantial IVC thrombosis and 4 (1.2%) had developed IVC occlusion.

CONCLUSIONS

The rates of symptomatic pulmonary embolism and filter-related complications were low after OptionELITE IVC filter placement, and filter retrieval, when attempted, was 99% successful.

Predicting the Safety and Effectiveness of Inferior Vena Cava Filters (PRESERVE): Outcomes at 12 months

OBJECTIVE

To determine the safety and effectiveness of vena cava filters (VCFs).

METHODS

A total of 1429 participants (62.7 ± 14.7 years old; 762 [53.3% male]) consented to enroll in this prospective, nonrandomized study at 54 sites in the United States between October 10, 2015, and March 31, 2019. They were evaluated at baseline and at 3, 6, 12, 18, and 24 months following VCF implantation. Participants whose VCFs were removed were followed for 1 month after retrieval. Follow-up was performed at 3, 12, and 24 months. Predetermined composite primary safety (freedom from perioperative serious adverse events [AEs] and from clinically significant perforation, VCF embolization, caval thrombotic occlusion, and/or new deep vein thrombosis [DVT] within 12-months) and effectiveness (composite comprising procedural and technical success and freedom from new symptomatic pulmonary embolism [PE] confirmed by imaging at 12-months in situ or 1 month postretrieval) end points were assessed.

RESULTS

VCFs were implanted in 1421 patients. Of these, 1019 (71.7%) had current DVT and/or PE. Anticoagulation therapy was contraindicated or had failed in 1159 (81.6%). One hundred twenty-six (8.9%) VCFs were prophylactic. Mean and median follow-up for the entire population and for those whose VCFs were not removed was 243.5 ± 243.3 days and 138 days and 332.6 ± 290 days and 235 days, respectively. VCFs were removed from 632 (44.5%) patients at a mean of 101.5 ± 72.2 days and median 86.3 days following implantation. The primary safety end point and primary effectiveness end point were both achieved. Procedural AEs were uncommon and usually minor, but one patient died during attempted VCF removal. Excluding strut perforation greater than 5 mm, which was demonstrated on 31 of 201 (15.4%) patients' computed tomography scans available to the core laboratory, and of which only 3 (0.2%) were deemed clinically significant by the site investigators, VCF-related AEs were rare (7 of 1421, 0.5%). Postfilter, venous thromboembolic events (none fatal) occurred in 93 patients (6.5%), including DVT (80 events in 74 patients [5.2%]), PE (23 events in 23 patients [1.6%]), and/or caval thrombotic occlusions (15 events in 15 patients [1.1%]). No PE occurred in patients following prophylactic placement.

CONCLUSIONS

Implantation of VCFs in patients with venous thromboembolism was associated with few AEs and with a low incidence of clinically significant PEs.

Predicting the Safety and Effectiveness of Inferior Vena Cava Filters (PRESERVE): Outcomes at 12 months

OBJECTIVE

To determine the safety and effectiveness of vena cava filters (VCFs).

METHODS

A total of 1429 participants (62.7 ± 14.7 years old; 762 [53.3% male]) consented to enroll in this prospective, nonrandomized study at 54 sites in the United States between October 10, 2015, and March 31, 2019. They were evaluated at baseline and at 3, 6, 12, 18, and 24 months following VCF implantation. Participants whose VCFs were removed were followed for 1 month after retrieval. Follow-up was performed at 3, 12, and 24 months. Predetermined composite primary safety (freedom from perioperative serious adverse events [AEs] and from clinically significant perforation, VCF embolization, caval thrombotic occlusion, and/or new deep vein thrombosis [DVT] within 12-months) and effectiveness (composite comprising procedural and technical success and freedom from new symptomatic pulmonary embolism [PE] confirmed by imaging at 12-months in situ or 1 month postretrieval) end points were assessed.

RESULTS

VCFs were implanted in 1421 patients. Of these, 1019 (71.7%) had current DVT and/or PE. Anticoagulation therapy was contraindicated or had failed in 1159 (81.6%). One hundred twenty-six (8.9%) VCFs were prophylactic. Mean and median follow-up for the entire population and for those whose VCFs were not removed was 243.5 ± 243.3 days and 138 days and 332.6 ± 290 days and 235 days, respectively. VCFs were removed from 632 (44.5%) patients at a mean of 101.5 ± 72.2 days and median 86.3 days following implantation. The primary safety end point and primary effectiveness end point were both achieved. Procedural AEs were uncommon and usually minor, but one patient died during attempted VCF removal. Excluding strut perforation greater than 5 mm, which was demonstrated on 31 of 201 (15.4%) patients' computed tomography scans available to the core laboratory, and of which only 3 (0.2%) were deemed clinically significant by the site investigators, VCF-related AEs were rare (7 of 1421, 0.5%). Postfilter, venous thromboembolic events (none fatal) occurred in 93 patients (6.5%), including DVT (80 events in 74 patients [5.2%]), PE (23 events in 23 patients [1.6%]), and/or caval thrombotic occlusions (15 events in 15 patients [1.1%]). No PE occurred in patients following prophylactic placement.

CONCLUSIONS

Implantation of VCFs in patients with venous thromboembolism was associated with few AEs and with a low incidence of clinically significant PEs.

Increased incidence of venous thromboembolism associated with inferior vena cava filter placement in patients diagnosed with isolated calf deep vein thrombosis after intracranial hemorrhage or intracranial operation

In this study, we sought to investigate the effectiveness of inferior vena cava (IVC) filter placement in reducing the incidence of venous thromboembolism (VTE) in patients diagnosed with isolated calf deep vein thrombosis (DVT) after an intracranial hemorrhage or intracranial operation. A retrospective chart review (January 2000-December 2019) was performed to identify patients diagnosed with calf DVT after intracranial hemorrhage or intracranial operation. A total of 100 patients met the study criteria and were divided into groups based on treatment: IVC filter placement (n = 22), prophylactic anticoagulation (n = 42), or imaging surveillance (n = 36). Treatment-related complications were identified, and differences between groups in the primary endpoint (VTE occurrence after DVT diagnosis) were assessed using logistic regression. VTE occurred in 15 patients after calf DVT diagnosis. The rate of VTE was higher in the IVC filter group (9/22; 41%) than in the anticoagulation (2/42; 5%; p = 0.002) and surveillance (4/36; 11%; p = 0.013) groups. These treatment effects remained significant after adjustments were made for baseline characteristics (IVC filter vs anticoagulation, p = 0.009; IVC filter vs surveillance, p = 0.019). There was a single occurrence of pulmonary embolism in the surveillance group (3%). A single case of IVC filter thrombus was identified; no anticoagulation-related complications were reported. The findings of this study do not support IVC filter placement as a primary and solitary treatment for isolated calf DVT occurring after intracranial hemorrhage or intracranial operation.

Clinical outcomes of AngioJet pharmacomechanical thrombectomy versus catheter-directed thrombolysis for the treatment of filter-related caval thrombosis

BACKGROUND

The inferior vena cava filter is utilized worldwide to intercept thrombi and to reduce the risk of fatal pulmonary embolism (PE). However, filter-related thrombosis is a complication of filter implantation. Endovascular methods such as AngioJet rheolytic thrombectomy (ART) and catheter-directed thrombolysis (CDT) can treat filter-related caval thrombosis, but the clinical outcomes of both treatment modalities have not been determined.

AIM

To compare the treatment outcomes of AngioJet rheolytic thrombectomy vs catheter-directed thrombolysis in patients with filter-related caval thrombosis.

METHODS

In this single-center retrospective study, 65 patients (34 males and 31 females; mean age: 59.0 ± 13.43 years) with intrafilter and inferior vena cava thrombosis were enrolled between January 2021 and August 2022. These patients were assigned to either the AngioJet group (n = 44) or the CDT group (n = 21). Clinical data and imaging information were collected. Evaluation measures included thrombus clearance rate, periprocedural complications, urokinase dosage, incidence of PE, limb circumference difference, length of stay, and filter removal rate.

RESULTS

Technical success rates were 100% in the AngioJet and CDT groups. In the AngioJet group, grade II and grade III thrombus clearance was achieved in 26 (59.09%) and 14 (31.82%) patients, respectively. In the CDT group, grade II and grade III thrombus clearance was accomplished in 11 (52.38%) patients and 8 (38.10%) patients, respectively (P > 0.05).The peridiameter difference of the thigh was significantly reduced in patients from both groups after treatment (P < 0.05). The median dosage of urokinase was 0.08 (0.02, 0.25) million U in the AngioJet group and 1.50 (1.17, 1.83) million U in the CDT group (P < 0.05). Minor bleeding was shown in 4 (19.05%) patients in the CDT group, and when it was compared with that in the AngioJet group, the difference was statistically significant (P < 0.05). No major bleeding occurred. Seven (15.91%) patients in the AngioJet group had hemoglobinuria and 1 (4.76%) patient in the CDT group had bacteremia. There were 8 (18.18%) patients with PE in the AngioJet group and 4 (19.05%) patients in the CDT group before the intervention (P > 0.05). Computed tomography angiopulmonography (CTA) showed that PE was resolved after the intervention. New PE occurred in 4 (9.09%) patients in the AngioJet group and in 2 (9.52%) patients in the CDT group after theintervention (P > 0.05). These cases of PE were asymptomatic. The mean length of stay was longer in the CDT group (11.67 ± 5.34 d) than in the AngioJet group (10.64 ± 3.52 d) (P < 0.05). The filter was successfully retrieved in the first phase in 10 (47.62%) patients in the CDT group and in 15 (34.09%) patients in the AngioJet group (P > 0.05).Cumulative removal was accomplished in 17 (80.95%) out of 21 patients in the CDT group and in 42 (95.45%) out of 44 patients in the ART group (P > 0.05). The median indwelling time for patients with successful retrieval was 16 (13139) d in the CDT group and 59 (12231) d in the ART group (P > 0.05).

CONCLUSION

Compared with catheter-directed thrombolysis, AngioJet rheolytic thrombectomy can achieve similar thrombus clearance effects, improve the filter retrieval rate, reduce the urokinase dosage and lower the risk of bleeding events in patients with filter-related caval thrombosis.

Improving the rate of inferior vena cava filter retrieval through multidisciplinary engagement

Background

The placement of retrievable inferior vena cava (IVC) filters occurs commonly, but retrieval rates remain low. Consequently, there is an unmet clinical need to ensure appropriate follow-up and retrieval of these devices.

Objectives

To determine the association between an IVC filter surveillance team with filter retrievals or a documented filter plan, time to retrieval, and incidence of filter complications or recurrent venous thromboembolism.

Methods

Ambidirectional cohort study evaluating consecutive IVC filter insertions before and after the implementation of a multidisciplinary surveillance team (MDST). We report an odds ratio (OR) with 95% CIs, adjusted by age, sex, weight, and malignancy status.

Results

Overall, 453 patients were included, with 272 individuals in the pre-MDST cohort and 181 individuals in the post-MDST cohort. The MDST was associated with a higher composite primary outcome of IVC filter retrieval or a documented filter plan from 79.4% in the pre-MDST cohort to 96.1% in the post-MDST cohort (OR, 6.44; 95% CI, 3.06-15.84). Compared with the pre-MDST cohort, IVC filter retrieval rates were higher in the post-MDST cohort (52.6%-73.5%, respectively; (OR, 2.50; 95% CI, 1.67-3.78). The MDST was associated with a shorter median time-to-filter retrieval (187-150 days, hazard ratio, 1.78; 95% CI, 1.39-2.29), but there was no significant difference when comparing symptomatic or clinically significant IVC filter complications, recurrent venous thromboembolism, or mortality.

Conclusion

Our study demonstrates the importance of a structured program to ensure timely IVC filter retrieval and ultimately improve patient care.

A review of inferior vena cava filters

The care of patients with venous thromboembolism (VTE) is delivered via a multidisciplinary team. The primary treatment for VTE is anticoagulation; however, placement of filter devices in the inferior vena cava (IVC) to prevent embolisation of deep venous thrombosis (DVT) is a well-established secondary treatment option. Many controversies remain regarding utilisation and management of filters.

Removal of inferior vena cava filter by open surgery after failure of endovenous retrieval

Background

The permanent placement of inferior vena cava (IVC) filters may lead to numerous complications and their removal is recommended once the risk of pulmonary embolism is reduced. Removal of IVC filters by endovenous means is preferred. But failure of endovenous removal happens when recycling hooks penetrate the vein wall and filters are left in place for too long time. In these scenarios, open surgery may be effective for removal of IVC filters. We aimed to describe the surgical approach, outcomes, and 6-month follow-up of the removal of IVC filter by open surgery, after the failure of removal via the endovenous method.

Methods

A total of 1,285 patients with retrievable IVC filters were admitted from July 2019 to June 2021, including 1,176 (91.5%) endovenous filter removals, and 24 (1.9%) open surgical IVC filter removals after the failure by endovenous method, of whom 21 (1.6%) were followed-up and eligible for analysis of the study. Patient characteristics, filter type, filter removal rate, IVC patency rate, and complications were retrospectively analyzed.

Results

Twenty-one patients were left with IVC filters for 26 (10, 37) months, of which 17 (81.0%) patients had non-conical filters and 4 (19.0%) had conical filters; all 21 filters were successfully removed, with a 100% removal rate, no deaths, no serious complications, and no symptomatic pulmonary embolism. At the 3rd month follow-up after surgery and 3rd month follow-up after discontinuation of anticoagulation therapy, only 1 case (4.8%) had IVC occlusion, but without any occurrence of new lower limb deep venous thrombosis and silent pulmonary embolism.

Conclusion

Open surgery can be used for the removal of IVC filters after failure of removal by endovenous method or when accompanied by complications without symptoms of pulmonary embolism. Open surgical approach can be used as an adjunctive clinical intervention for the removal of such filters.

Automated detection of IVC filters on radiographs with deep convolutional neural networks

PURPOSE

To create an algorithm able to accurately detect IVC filters on radiographs without human assistance, capable of being used to screen radiographs to identify patients needing IVC filter retrieval.

METHODS

A primary dataset of 5225 images, 30% of which included IVC filters, was assembled and annotated. 85% of the data was used to train a Cascade R-CNN (Region Based Convolutional Neural Network) object detection network incorporating a pre-trained ResNet-50 backbone. The remaining 15% of the data, independently annotated by three radiologists, was used as a test set to assess performance. The algorithm was also assessed on an independently constructed 1424-image dataset, drawn from a different institution than the primary dataset.

RESULTS

On the primary test set, the algorithm achieved a sensitivity of 96.2% (95% CI 92.7-98.1%) and a specificity of 98.9% (95% CI 97.4-99.5%). Results were similar on the external test set: sensitivity 97.9% (95% CI 96.2-98.9%), specificity 99.6 (95% CI 98.9-99.9%).

CONCLUSION

Fully automated detection of IVC filters on radiographs with high sensitivity and excellent specificity required for an automated screening system can be achieved using object detection neural networks. Further work will develop a system for identifying patients for IVC filter retrieval based on this algorithm.

Changes in perfusion angiography after IVC filter placement and retrieval

Inferior vena cava (IVC) filters are posited to effect flow dynamics, causing turbulence, vascular remodeling and eventual thrombosis; however, minimal data exists evaluating hemodynamic effects of IVC filters in vivo. The purpose of this study was to determine differences in hemodynamic flow parameters acquired with two-dimension (2D)-perfusion angiography before and after IVC filter placement or retrieval. 2D-perfusion images were reconstructed retrospectively from digital subtraction angiography from a cohort of 37 patients (13F/24M) before and after filter placement (n = 18) or retrieval (n = 23). Average dwell time was 239.5 ± 132.1 days. Changes in the density per pixel per second within a region of interest (ROI) were used to calculate contrast arrival time (AT), time-to-peak (TTP), wash-in-rate (WIR), and mean transit time (MTT). Measurements were obtained superior to, inferior to, and within the filter. Differences in hemodynamic parameters before and after intervention were compared, as well as correlation between parameters versus filter dwell time. A P value with Bonferroni correction of <.004 was considered statistically significant. After placement, there was no difference in any 2D-perfusion variable. After retrieval, ROIs within and inferior to the filter showed a significantly shorter TTP (1.7 vs 1.4 s, P = .004; 1.5 vs 1.3 s, P = .001, respectively) and MTT (1.7 vs 1.4 s, P = .003; 1.5 vs 1.2 s, P = .002, respectively). Difference in variables showed no significant correlation when compared to dwell time. 2D-perfusion angiography is feasible to evaluate hemodynamic effects of IVC filters in vivo. TTP and MTT within and below the filter after retrieval were significantly changed, without apparent correlation to dwell time, suggesting a functional hemodynamic delay secondary to filter presence.