Decision analysis of retrievable inferior vena cava filters in patients without pulmonary embolism

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.

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.

Fifteen-Year Trend in Inferior Vena Cava Filter Utilization before and after U.S. Food and Drug Administration Communications: Data from the National Inpatient Sample 2005-2019

The purpose of this study was to evaluate the contemporary trends in inferior vena cava (IVC) filter utilization in the inpatient setting following the U.S. Food and Drug Administration (FDA) safety communications and compare those trends in relation to incidence of hospital admissions involving venous thromboembolism (VTE). The National Inpatient Sample was queried between 2005 and 2019. There was an increasing trend in the utilization of IVC filters between 2005 and 2010 (P < .01). Following the FDA communication in 2010, this reversed to a decreasing trend (P < .001), which persisted following the second FDA communication in 2014, although there was no significant change in the rate of decline (P = .67). Throughout the study period, the proportion of IVC filters placed in patients with VTE increased from 70.8% to 82.2%.

Evolving Landscape of Inferior Vena Cava Filter Utilization: A Comprehensive Bibliometric Analysis

This bibliometric analysis scrutinizes the evolution and current challenges in the use of Inferior Vena Cava (IVC) filters, focusing on trends from 2004 to 2023. Analyzing 2470 records, we report the United States' dominant role, with over half of the studies, and a significant shift towards retrievable filters. Despite technological advancements, controversies persist regarding efficacy, safety, and retrieval issues. Our findings point to the need for refined clinical guidelines and enhanced management strategies to navigate the complex landscape of IVC filter utilization effectively.

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.

Comparison of inferior vena cava filter use and outcomes between cancer and non-cancer patients in a tertiary hospital

BACKGROUND

While accepted indications for the use of inferior vena cava filter (IVCF) in patients with a venous thromboembolism (VTE) have remained stable, their use continues to be frequent. Retrieval rates are still low, being particularly notable in the population with cancer. This study aims to review the rate of adherence to guidelines recommendation and to compare retrieval rates and complications in both cancer and non-cancer patients.

METHODS

A retrospective study was performed including 185 patients in whom an IVCF was placed in Hospital Clinic of Barcelona. Baseline characteristics, clinical outcomes, and IVCF-related outcomes were analyzed. A strongly recommended indication (SRI) was considered if it was included in all the revised clinical guidelines and non-strongly if it was included in only some.

RESULTS

Overall, 47 % of the patients had a SRI, without differences between groups. IVCF placement after 29 days from the VTE event was more frequent in the cancer group (46.1 vs. 17.7 %). Patients with cancer (48.1 % of the cohort) were older, with higher co-morbidity and bleeding risk. Anticoagulation resumption (75.3 % vs. 92.7 %) and IVCF retrieval (50.6 % vs. 66.7 %) were significantly less frequent in cancer patients. No significant differences were found regarding IVCF-related complications, hemorrhagic events and VTE recurrence.

CONCLUSIONS

SRI of IVCF placement was found in less than half of the patients. Cancer patients had higher rates of IVCF placement without indication and lower anticoagulation resumption and IVCF retrieval ratios, despite complications were similar in both groups.

The Role of IVC Filters in the Management of Acute Pulmonary Embolism

Venous thromboembolism (VTE), comprising deep venous thrombosis (DVT) and pulmonary embolism (PE), is a prevalent cardiovascular condition, ranking third globally after myocardial infarction and stroke. The risk of VTE rises with age, posing a growing concern in aging populations. Acute PE, with its high morbidity and mortality, emphasizes the need for early diagnosis and intervention. This review explores prognostic factors for acute PE, categorizing it into low-risk, intermediate-risk, and high-risk based on hemodynamic stability and right ventricular strain. Timely classification is crucial for triage and treatment decisions. In the contemporary landscape, low-risk PE patients are often treated with Direct Oral Anticoagulants (DOACS) and rapidly discharged for outpatient follow-up. Intermediate- and high-risk patients may require advanced therapies, such as systemic thrombolysis, catheter-directed thrombolysis, mechanical thrombectomy, and IVC filter placement. The latter, particularly IVC filters, has witnessed increased usage, with evolving types like retrievable and convertible filters. However, concerns arise regarding complications and the need for timely retrieval. This review delves into the role of IVC filters in acute PE management, addressing their indications, types, complications, and retrieval considerations. The ongoing debate surrounding IVC filter use, especially in patients with less conventional indications, reflects the need for further research and data. Despite complications, recent studies suggest that clinically significant issues are rare, sparking discussions on the appropriate and safe utilization of IVC filters in select PE cases. The review concludes by highlighting current trends, gaps in knowledge, and potential avenues for advancing the role of IVC filters in future acute PE management.

Laser-assisted permanent greenfield filter removal with ileocaval stent reconstruction following filter thrombosis, a case report

Emerging literature supports removal of chronic indwelling IVC filters when they are contributing to complications for a patient and are no longer indicated. We present an interesting case of an elderly patient who had a history of DVT and underwent spinal surgery, which required cessation of his anticoagulation and placement of an IVC filter pre-operatively. Approximately 15 years later the patient presented to our institution with chronic occlusion of his IVC at the level of his filter which had never been removed, with bilateral lower extremity DVT and symptoms of phlegmasia cerulea dolens. Despite a previous unsuccessful attempt at DVT thrombectomy at an outside institution, interventional radiology was consulted, and he subsequently underwent successful laser sheath assisted removal of his 15-year-old permanent Greenfield filter with bilateral lower extremity DVT thrombectomy and venous stenting with significant improvement in his presenting symptoms. Clinical presentation, diagnostic workup, case findings, and outcomes are described.

Predictors of endobronchial forceps utilization for inferior vena cava filter retrieval: when snare retrieval fails

BACKGROUND

Endobronchial forceps are commonly used for complex IVC filter removal and after initial attempts at IVC filter retrieval with a snare have failed. Currently, there are no clear guidelines to help distinguish cases where primary removal should be attempted with standard snare technique or whether attempts at removal should directly be started with forceps. This study is aimed to identify clinical and imaging predictors of snare failure which necessitate conversion to endobronchial forceps.

METHODS

Retrospective analysis of 543 patients who underwent IVC filter retrievals were performed at three large quaternary care centers from Jan 2015 to Jan 2022. Patient demographics and IVC filter characteristics on cross-sectional images (degree of tilt, hook embedment, and strut penetration, etc.) were reviewed. Binary multivariate logistic regression was used to identify predictors of IVC filter retrieval where snare retrieval would fail.

RESULTS

Thirty seven percent of the patients (n = 203) necessitated utilization of endobronchial forceps. IVC filter hook embedment (OR:4.55; 95%CI: 1.74-11.87; p = 0.002) and strut penetration (OR: 56.46; 95% CI 20.2-157.7; p = 0.001) were predictors of snare failure. In contrast, total dwell time, BMI, and degree of filter tilt were not associated with snare failure. Intraprocedural conversion from snare to endobronchial forceps was significantly associated with increased contrast volume, radiation dose, and total procedure times (p < 0.05).

CONCLUSION

IVC filter hook embedment and strut penetration were predictors of snare retrieval failure. Intraprocedural conversion from snare to endobronchial forceps increased contrast volume, radiation dose, and total procedure time. When either hook embedment or strut penetration is present on pre-procedural cross-sectional images, IVC filter retrieval should be initiated using endobronchial forceps.

LEVEL OF EVIDENCE

Level 3, large multicenter retrospective cohort.

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.

Acute venous problems: Integrating medical, surgical, and interventional treatments

"Acute venous problems" refers to a group of disorders that affect the veins and result in sudden and severe symptoms. They can be classified based on the pathological triggering mechanisms, such as thrombosis and/or mechanical compression, and their consequences, including symptoms, signs, and complications. The management and therapeutic approach depend on the severity of the disease, the location, and the involvement of the vein segment. Although summarizing these conditions can be challenging, the objective of this narrative review was to provide an overview of the most common acute venous problems. This will include an exhaustive yet concise and practical description of each condition. The multidisciplinary approach remains one of the major advantages in dealing with these conditions, maximizing the results and the prevention of complications.

Complex Inferior Vena Cava Filter Retrievals: Success Rate and Predictors of Adverse Events at a Large Specialized Referral Center

BACKGROUND. Specialized inferior vena cava (IVC) filter referral centers can achieve improved retrieval outcomes, potentially facilitating complex retrievals after long filter dwell times. OBJECTIVE. The purpose of this study was to determine the success rate of complex IVC filter retrievals at a large specialized IVC filter referral center and to identify predictors of adverse events during complex retrievals. METHODS. This retrospective study included patients who underwent complex IVC filter retrieval from March 2014 to June 2018 at a large regional health system with specialized complex retrieval referral centers and interventional radiologists with expertise in such procedures. Complex retrievals methods included a range of loop snare, coaxial sheath, forceps, and snare techniques. Data were collected from the electronic medical record. The success rate of complex retrieval was determined. Factors associated with adverse events during retrieval procedures were explored. RESULTS. The study included 125 patients (51 women, 74 men; mean age, 60 years). The mean filter dwell time at retrieval was 47.5 months (median, 21.8 months). The complex retrieval success rate was 99.2% on the first attempt and 100.0% overall. A total of 11.2% (14/125) of patients experienced an adverse event during retrieval, including 10.4% (13/125) with minor and 0.8% (1/125) with major events. Prolonged dwell time was the only indication for complex retrieval that was significantly associated with adverse events (adverse event rate, 16.7% for patients with this indication vs 5.1% for patients without this indication; p = .04). In multiple regression analysis, the only significant independent predictor of adverse events was a filter dwell time of 5 years or longer (odds ratio, 6.98 [95% CI, 1.64-29.81]; p = .009). CONCLUSION. In a specialized referral system with expertise in complex retrieval methods, high retrieval success rates can be achieved in patients who have filters with long dwell times. Nonetheless, longer dwell times are associated with adverse events during retrieval procedures. CLINICAL IMPACT. The observations support performing early filter retrieval and referring patients who have filters with prolonged dwell times to specialized centers.

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.

Retrievable Inferior Vena Cava Filters-Use, Removal, and Removal Techniques

The use of retrievable inferior vena cava filters is on the rise, but there is an inadequate number of these filters being removed even if their use as a prophylactic for venous thromboembolism is no longer indicated. Complications with retrievable filters that remain in the patient for an extended duration include examples such as filter tilt and embedding into the caval wall. This raises concerns for whether the filter is properly functioning and for consequent sequelae, including recurrent thrombosis, stenosis, or inferior vena cava perforation. With these complications, there are also challenges to retrieving these filters via the standard techniques and thus more advanced techniques are required. Both standard and advanced techniques, their uses, and possible risks of these methods are also discussed.

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.

Effectiveness and Safety of Laser-Assisted Removal of Inferior Vena Cava (IVC) Filters in a Single Tertiary Care Center

INTRODUCTION

Laser sheath-assisted removal of inferior vena cava (IVC) filters with long dwelling time is a technique that utilizes laser-tipped sheaths. The laser light only penetrates vascular tissue by one hundred microns, causing the target tissues to disintegrate into particles less than 5 microns in size. This approach reduces the energy used during difficult retrieval procedures, allowing permanent filters to be removed in less fluoroscopic and procedural time overall.

MATERIALS AND METHODS

The radiology information system and electronic health records were used in this retrospective cohort study to retrieve the data. A total of nine consecutive patients who underwent laser-assisted filter removal utilizing GlideLightTM were included in the study between January 2016 and January 2017. The study took place at King Abdulaziz Medical City in Riyadh. In this study, five patients were male and four were female with ages ranging from 19 to 57 years with a median age of 31.

RESULTS

During the period of the study, a total of nine patients had their IVC filters removed using a laser. The success rate was 100%. The indications were trauma (n=4) followed by deep vein thrombosis (DVT) (n=3) and one patient indication was prolonged immobilization. The dwelling time ranged from seven to 70 months, with a dwelling median of 19 months.

CONCLUSION

A laser sheath might be necessary for closed-cell filters in order to improve the likelihood of a successful and secure retrieval. Technical efficiency, filter type, the necessity of applying a laser sheath based on an open versus closed filter design, dwell times, and unfavorable results. As a result, after typical procedures failed to successfully retrieve IVC filters with long dwell durations, laser-assisted filter removal is thought to be practical and safe.

Outcomes of bellwether cases related to inferior vena cava filters in multidistrict litigations

OBJECTIVE

In the present study, we identified and reviewed the outcomes of bellwether cases related to inferior vena cava (IVC) filter multidistrict litigations (MDLs).

METHODS

The legal research database, LexisNexis (New York, NY), was used to identify all cases related to IVC filters. Cases unrelated to the MDLs were excluded. Court documents recording the proceedings for bellwether cases sent to jury trials were retrieved from the LexisNexis subsidiary, Law360. Data on plaintiffs, filter models, reported complications, filed claims, decision-making body, verdicts, and rewards were reviewed.

RESULTS

A total of 678 cases pertaining to IVC filters were found in the database, of which 12 were identified as bellwether cases for MDL. Of the 12, 2 (16.7%) were initially ruled in favor of the plaintiffs in jury trials, although the judgment for 1 of these was later vacated by a judge. The remaining 10 (83.3%) had been decided in favor of the manufacturers by judges and juries.

CONCLUSIONS

Verdicts in all bench trials were in favor of manufacturers, suggesting that judges perceived the presented complications by patients to be within the normal realm of the expected risk of IVC filter use. The findings from the present study have emphasized the treating physicians' legal responsibility to adequately warn patients of all the associated risks with IVC filters. The findings have also indicated that physicians can still be found liable in product liability cases directed at manufacturers. Physicians should continue to actively monitor patients to optimize the IVC retrieval windows.

Inferior Vena Cava Filter Litigation Review: An Analysis of Medicolegal Cases Pertaining to Inferior Vena Cava Filters

PURPOSE

To identify and analyze all medical malpractice and product liability lawsuits pertaining to inferior vena cava (IVC) filters published within a well-recognized legal research database.

MATERIALS AND METHODS

LexisNexis, a legal research database, was used to retrieve cases that mentioned harm from IVC filters, or lack thereof, as the cause for legal action. A total of 672 cases were analyzed for type of case (medical malpractice or product liability), filter model implanted, filter complications, court decisions, and settlement payments if any.

RESULTS

Of 95 analyzed cases, 20 (21.1%) were medical malpractice cases and 75 (78.9%) were product liability cases. C.R. Bard was the manufacturer associated with the most lawsuits (n = 41, 48.8%). The most litigious filters were the G2 filter from C.R. Bard (n = 17, 20.2%) and Greenfield filter from Boston Scientific (n = 17). The most common complications were IVC penetration (n = 26, 29.9%), filter migration (n = 26, 29.9%), filter fracture (n = 23, 26.4%), and tilt (n = 16, 18.4%). The number of product liability cases has increased from accounting for 25.0% (2 of 8) of filter lawsuits between 2000 and 2010 to 83.9% (73 of 87) during 2011-2020. Of the 20 medical malpractice claims, 9 (45%) were filed for failure to place a filter. One physician was found liable for filter-related complications by a state court in 2014.

CONCLUSIONS

The majority of recent IVC filter-related lawsuits are filed against manufacturers on the basis of product liability claims, with the main litigious filters being the G2 and Greenfield filters. Most cases resulted in rulings for physicians or manufacturers. Some were filed against physicians for filter-related complications or for failure to place an IVC filter.

May-Thurner Syndrome-a Rare Cause of Extensive Pelvic DVT, but Is there More to Know?

May-Thurner Syndrome (MTS) is a rare anatomical variant characterized by the compression of the left common iliac artery by the right common iliac artery against the fifth lumbar vertebrae. It can present as acute or chronic deep vein thrombosis (DVT), leg pain, varicosities, skin ulceration, and hyperpigmentation. In this case report, we present an interesting case of a young male with no obvious risk factors, who presented with back and left lower extremity pain later diagnosed with MTS on computed tomography angiography (CTA) and venogram. The patient was treated with venoplasty and pharmacomechanical thrombolysis and was discharged on apixaban.

Safety and efficacy of inferior vena cava filter retrieval: a 5-year single center retrospective review from a tertiary care center

Background

Inferior vena cava (IVC) filter retrieval is typically accomplished with standard snare technique. When this fails, more advanced techniques are necessary, especially when removal falls outside a 12-month window. Complications during filter retrieval depend heavily on technique, type of filter, and filter position. In this study we examined safety and efficacy of 536 filter retrievals at a tertiary care center and compared complication rates between standard snare and endobronchial forcep retrieval.

Method

We reviewed 536 cases between August 2015 and August 2020, recording retrieval success rates, patient comorbidities, and complication rates at the time of removal.

Results

Total overall retrieval success was 97.9% (525/536), and complications occurred in approximately 6.0% (32/536) of all cases. Success and complications with standard snare technique alone were 99.4% (345/347) and 1.7% (5 Grade I/II, 1 Grade III) and advanced forcep technique 98.8% (171/173) and 14.5% (22 Grade I/II, 2 Grade III, and 1 Grade IV), respectively. There was no significant difference between the technical success rates of the standard snare technique and forceps techniques (p = 0.60) despite a significantly longer dwell time in patients undergoing forceps retrieval (p < 0.001).

Conclusion

To our knowledge, this is the largest cohort of forceps directed IVC filter retrieval present in the literature. Rates of successful endobronchial forceps and standard snare retrievals in this study are similar to previous reports. Although use of endobronchial forceps may be associated with higher complication rates, this is likely due to prolonged dwell times, filter tilt, and attempted removal of non retrievable filters. Overall, forceps-directed retrieval offers a safe, effective means of removal in difficult cases.

Level of evidence

Level 3, Large Retrospective Study.

Population-Based Disparities in Inferior Vena Cava Filter Procedures Among Medicare Enrollees With Acute Venous Thromboembolism

PURPOSE

Venous thromboembolism (VTE) imposes a significant clinical and financial burden on patients and society. Inferior vena cava filters (IVCFs) are considered for patients with absolute contraindications or failures of anticoagulation. However, studies examining the population-based disparities of IVCF placement and retrieval are limited. The association between patient and clinical characteristics in the likelihood of and time to IVCF placement and retrievals in a nationally representative cohort was examined.

METHODS

Medicare patients aged ≥65 years with index VTE claims between 2015 and 2018 were followed through 2019 to identify IVCF placements and retrievals. Rates were compared using survival analysis methods.

RESULTS

Of the 516,978 patients with VTE diagnoses, 5,864 (1.1%) had IVCFs placed, and 1,884 (32.1%) of those underwent retrieval procedures. Placement and retrieval rates varied significantly by demographics, comorbidity burden, and geographic region. From Cox regression, older age (hazard ratio [HR], 1.26; P < .0001), higher baseline comorbidity (Elixhauser) score (HR, 1.07; P < .0001), and outpatient (vs inpatient) site of VTE service (HR, 2.11; P < .0001) were associated with increased frequency of IVCF placement. The rate of retrieval was significantly lower for men (HR, 0.83; P = .0393), patients with higher comorbidity scores (HR, 0.95; P = .0037), and those with outpatient (vs inpatient) VTE sites of service (HR, 0.77; P = .0173). Neither facility- nor county-level characteristics were significantly associated with placements or retrievals.

CONCLUSIONS

This large cohort of Medicare beneficiaries with newly diagnosed VTE demonstrated inequities in IVCF placement and retrieval.

Bismuth Nanoparticle and Polyhydroxybutyrate Coatings Enhance the Radiopacity of Absorbable Inferior Vena Cava Filters for Fluoroscopy-Guided Placement and Longitudinal Computed Tomography Monitoring in Pigs

Inferior vena cava filters (IVCFs) constructed with poly-p-dioxanone (PPDO) are promising alternatives to metallic filters and their associated risks and complications. Incorporating high-Z nanoparticles (NPs) improves PPDO IVCFs' radiopacity without adversely affecting their safety or performance. However, increased radiopacity from these studies are insufficient for filter visualization during fluoroscopy-guided PPDO IVCF deployment. This study focuses on the use of bismuth nanoparticles (BiNPs) as radiopacifiers to render sufficient signal intensity for the fluoroscopy-guided deployment and long-term CT monitoring of PPDO IVCFs. The use of polyhydroxybutyate (PHB) as an additional layer to increase the surface adsorption of NPs resulted in a 2-fold increase in BiNP coating (BiNP-PPDO IVCFs, 3.8%; BiNP-PPDO + PHB IVCFs, 6.2%), enabling complete filter visualization during fluoroscopy-guided IVCF deployment and, 1 week later, clot deployment. The biocompatibility, clot-trapping efficacy, and mechanical strength of the control PPDO (load-at-break, 6.23 ± 0.13 kg), BiNP-PPDO (6.10 ± 0.09 kg), and BiNP-PPDO + PHB (6.15 ± 0.13 kg) IVCFs did not differ significantly over a 12-week monitoring period in pigs. These results indicate that BiNP-PPDO + PHB can increase the radiodensity of a novel absorbable IVCF without compromising device strength. Visualizing the device under conventional radiographic imaging is key to allow safe and effective clinical translation of the device.

Vena Cava Filters: Toward Optimal Strategies for Filter Retrieval and Patients' Follow-Up

Mortality rates associated with venous thromboembolism (VTE) are high. Inferior vena cava filters (IVCFs) have been frequently placed for these patients as part of their treatment, albeit the paucity of data showing their ultimate efficacy and potential risk of complications. Issues regarding long-term filter dwell time are accounted for in society guidelines. This topic has led to an FDA mandate for filter retrieved as soon as protection from pulmonary embolism is no longer needed. However, even though most are retrievable, some were inadvertently left as permanent, which carries an incremental lifetime risk to the patient. In the past decade, attempts have aimed to determine the optimal time interval during which filter needs to be removed. In addition, distinct strategies have been implemented to boost retrieval rates. This review discusses current conflicts in indications, the not uncommon complications, the rationale and need for timely retrieval, and different quality improvement strategies to fulfill this aim.

Impact of dedicated outpatient pulmonary follow‐up for hospitalized patients with acute pulmonary embolism

Pulmonary embolism (PE) response teams are the standard of care for the management of acute PE. The complications of PE extend far beyond the initial hospitalization period. In this study, we examined the role and potential benefits of dedicated pulmonary follow‐up after hospital discharge for patients with PE.

Ibero-American Society of Interventionism (SIDI) and the Spanish Society of Vascular and Interventional Radiology (SERVEI) Standard of Practice (SOP) for the Management of Inferior Vena Cava Filters in the Treatment of Acute Venous Thromboembolism

Objectives: to present an interventional radiology standard of practice on the use of inferior vena cava filters (IVCFs) in patients with or at risk to develop venous thromboembolism (VTE) from the Iberoamerican Interventional Society (SIDI) and Spanish Vascular and Interventional Radiology Society (SERVEI). Methods: a group of twenty-two interventional radiologist experts, from the SIDI and SERVEI societies, attended online meetings to develop a current clinical practice guideline on the proper indication for the placement and retrieval of IVCFs. A broad review was undertaken to determine the participation of interventional radiologists in the current guidelines and a consensus on inferior vena cava filters. Twenty-two experts from both societies worked on a common draft and received a questionnaire where they had to assess, for IVCF placement, the absolute, relative, and prophylactic indications. The experts voted on the different indications and reasoned their decision. Results: a total of two-hundred-thirty-three articles were reviewed. Interventional radiologists participated in the development of just two of the eight guidelines. The threshold for inclusion was 100% agreement. Three absolute and four relative indications for the IVCF placement were identified. No indications for the prophylactic filter placement reached the threshold. Conclusion: interventional radiologists are highly involved in the management of IVCFs but have limited participation in the development of multidisciplinary clinical practice guidelines.

Indications and long-term outcomes of preoperative inferior vena caval filters in 111 patients at high risk of pulmonary embolism undergoing major abdominal surgery

AIMS

Patients with abdominal cancer requiring major surgical intervention are at high risk of venous thromboembolic events (VTE), particularly pulmonary emboli (PE). A proportion of patients with cancer can present with, or have had, major VTEs prior to definitive surgical treatment. Preoperative percutaneous inferior venal caval filters (IVCF) may reduce the risk of PE. The aim of this study was to assess the indications, complications, retrieval rates, and long-term outcome of IVCFs in patients undergoing major abdominal surgery.

METHODS

This was a retrospective analysis of a prospective IVCF database between 2007 and 2018 of all patients with IVCF insertion prior to major abdominal surgery. The indications for an IVCF, procedural complications and surgical interventions were recorded.

RESULTS

Overall, 111 patients had IVCF insertion. IVCF placement failed in one patient with gross abdominal disease. Indications for an IVCF were: prior PE in 65/111 (59%) and major vein thrombus in 42 (38%). Overall, 26/111 (23%) had the IVCF removed at a median of 91 days. In two patients IVCF removal failed. At follow-up of the 85 patients who had the IVCF left in situ, six developed filter-related thrombus and 13 a deep vein thrombosis (DVT). Four patients had a PE with an indwelling IVCF.

CONCLUSION

Preoperative IVCF may reduce perioperative PE in patients at high risk of thrombosis undergoing major abdominal surgery where early anticoagulation is contraindicated. Long-term follow-up of retained IVCF suggests that major problems are infrequent, though further thrombosis may occur and long-term anticoagulation may be needed.

Risk factors associated with complex inferior vena cava filter retrievals and complications: A 7-year retrieval database analysis and the impact on retrieval rates at an Australian tertiary centre

INTRODUCTION

Venous thromboembolism (VTE) affects approximately 17,000 Australians annually. While anticoagulation is the mainstay of treatment, inferior vena cava filters (IVCFs) are used in patients where this is contraindicated. The primary aim was to identify risk factors for complex retrievals and IVCF-related complications following the establishment of a database at a single tertiary centre. The secondary aim was to evaluate the IVCF retrieval rate and patients lost to follow-up.

METHODS

A retrospective study at a single tertiary centre was conducted on IVCFs inserted from 2012 to 2018. Logistic regression models were used to evaluate potential risk factors for filter-related complications and complex retrievals.

RESULTS

In total, 402 patients had an IVCF inserted. Of these, 308 patients (77%) had a retrieval attempted, 10 (3%) of which required more than one retrieval attempt (complex retrieval). Factors associated with filter-related complications included dwell time (OR 1.02, 95% CI: 1.01-1.04) and select indications for insertion, namely VTE requiring thrombolysis/thrombectomy (OR 2.29, 95% CI: 1.02-5.16) and iliocaval/free-floating iliofemoral DVT without thrombectomy/thrombolysis (OR 5.89, 95% CI: 1.53-22.71). After mutual adjustment for all variables, only dwell time remained a significant factor for filter-related complications (adjusted OR 1.03, 95% CI: 1.01-1.05) and complex retrieval (AOR 1.05, 95% CI: 1.02-1.08). The annual retrieval rate increased from 73% (2012) to 83% (2018), with an overall retrieval rate of 75%.

CONCLUSION

Dwell time is a potential risk factor for filter-related complications and complex retrievals. The annual IVCF retrieval rate was 75% since an Interventional Radiology-led database was established.

An expert spotlight on inferior vena cava filters

Introduction: Inferior vena cava (IVC) filters are mechanical filtration devices designed as an alternative to surgical ligation/plication of the IVC. Their use has been controversial, especially with the introduction of retrievable filters and expanded/prophylactic indications.Areas covered: Authors discuss the types of available IVC filters, indications for placement, evidence on their effectiveness in general and specific patient populations, procedural considerations, off-label use, complications, and filter retrieval. This review is based on manuscripts/abstracts published from 1960 to 2021 on venous thromboembolism and IVC filters.Expert opinion: Despite the limited data on their effectiveness and survival benefit, IVC filters continue to play an important role in the treatment of patients with venous thromboembolism (VTE) who cannot receive standard anticoagulation. There is no role of IVC filters in patients without VTE. While retrievable filters are desirable for short-term use, a dedicated team-based approach, and advanced training are required for their successful removal. Newer devices are promising in improving patient safety . The device manufacturers and regulatory agencies should consider specific approaches to track device-related adverse events. Population-based studies are required to establish optimal patient population who would benefit from these devices. .

IVC filter retrieval: a multicenter proposal of two score systems to predict application of complex technique and procedural outcome

PURPOSE

Aim of this study was to identify preprocedural parameters, which may predict the application of a complex IVC filter retrieval technique and estimate the procedural outcome by applying two dedicated score systems.

MATERIALS AND METHODS

In this retrospective multicenter analysis, data concerning patient, filter and procedure characteristics were retrieved from January 2018 to March 2020. Patients were evaluated according to the retrieval technique (standard vs. complex) and the procedural outcome (success vs. failure). Significant differences among these groups were evaluated, and two score systems were developed to predict the application of a complex retrieval technique and the procedural outcome.

RESULTS

One hundred and sixteen IVC filters were retrieved in 116 patients. In 98 subjects, the filter was retrieved with a standard procedure (Standard group, 84.5% vs. Complex group, 15.5%), while in 106 patients the procedure was successful (Success group, 91.4% vs. Failure group, 8.6%). Statistically significant differences were noted in terms of embedded filter hook, filter apex tilt, angle between filter axis and IVC, caval wall penetration, dwelling time and procedural time. Two score 0-5 points to predict the need for a complex retrieval technique and the procedural outcome were developed, with a prognostic accuracy of 88.8% and 91.4%, respectively.

CONCLUSION

Significant differences were appreciable analyzing the sample data comparing both the retrieval technique applied and the procedural outcome. Two predictive scores were developed to assess the need for applying a complex retrieval technique and to estimate the procedural outcome.

Venous thromboembolism prophylaxis in the trauma intensive care unit: an American Association for the Surgery of Trauma Critical Care Committee Clinical Consensus Document

Venous thromboembolism (VTE) is a potential sequela of injury, surgery, and critical illness. Patients in the Trauma Intensive Care Unit are at risk for this condition, prompting daily discussions during patient care rounds and routine use of mechanical and/or pharmacologic prophylaxis measures. While VTE rightfully garners much attention in clinical patient care and in the medical literature, optimal strategies for VTE prevention are still evolving. Furthermore, trauma and surgical patients often have real or perceived contraindications to prophylaxis that affect the timing of preventive measures and the consistency with which they can be applied. In this Clinical Consensus Document, the American Association for the Surgery of Trauma Critical Care Committee addresses several practical clinical questions pertaining to specific or unique aspects of VTE prophylaxis in critically ill and injured patients.

Inferior Vena Cava Filter Retrieval Trends: A Single-Center Experience

Recognition of the adverse events of inferior vena cava filters (VCFs) has prompted the Food and Drug Administration (FDA) to issue safety warnings (2010 and 2014), advocating for removal, once the risk of pulmonary embolism has abated. Despite an initial increase in retrieval rates, these remain low (25–30% at 1 year in 2014). We retrospectively investigated retrieval trends in adults with VCFs placed between 2015 and 2018 at a single institution. The rate of retrievable VCF removal accounting for the competing risk of death was the main outcome. There were 494 VCFs placed (305 retrievable). The cumulative incidence of retrieval remained low (21% at 1 year), even after the second FDA warning (2014). Patients who resumed anticoagulation (AC) at any time were more likely to have retrieval (hazard ratio [HR] = 3.6, p  < 0.01) and had higher retrieval rates at every time point (31.4 vs. 7.6% at 1 year). Advanced age (HR = 0.98 per year, p  = 0.004), stroke (HR = 0.28, p  = 0.028), and active malignancy (HR = 0.42, p  = 0.006) predicted nonretrieval. Device-related complications were infrequent (<1%) but thrombotic complications occurred early and were more common for nonretrieved VCFs (17 vs. 12%, p  = 0.29). Revision of guidelines to recommend active surveillance for the ability to tolerate AC in the immediate postimplantation period may improve retrieval rates.

Role of Inferior Vena Cava Filter Retrieval in Patients on Chronic Anticoagulation Therapy

Purpose of review

Describe the role of inferior vena cava filter (IVCF) retrieval in patients on chronic anticoagulation given the overlap of these treatment options in the management of patients with venous thromboembolic disease.

Recent findings

Despite the increase in IVCF retrievals since the Food and Drug Administration safety communications in 2010 and 2014, retrieval rates remain low. Previous studies have shown that longer filter dwell times are associated with greater risk for filter complications and more difficulty with filter retrievals. Recent findings suggest that complications are more frequent in the first 30 days after placement.

Summary

The decision to retrieve an optional IVCF is individualized and requires diligent follow-up with consistent re-evaluation of the need for the indwelling IVCF, particularly in those on long-term anticoagulation therapy.

Inferior vena cava filters: a framework for evidence-based use

Venous thromboembolism (VTE) is a common cause of morbidity and mortality. Although most patients can be managed safely with anticoagulation, inferior vena cava filters (IVCFs) represent an important alternative to anticoagulation in a small subset of patients. IVCF use has expanded exponentially with the advent of retrievable filters. Indications for IVCFs have liberalized despite limited evidence supporting this practice. Because indiscriminate use of IVCFs can be associated with net patient harm, knowledge of the risks and benefits of these devices is essential to optimal evidence-based practice. Patients with acute VTE and absolute contraindications to anticoagulation or major complications from anticoagulation are universally agreed indications for IVCFs. However, the reliance on IVCFs for primary VTE prophylaxis in high-risk patients is not substantiated by the available literature. This review examines trends in IVCF use, practice-based recommendations on IVCF use in various clinical scenarios, complications associated with indwelling IVCFs, and indications for IVCF retrieval.

Penetration of Bone by Inferior Vena Cava Filters: Safety and Technical Success of Percutaneous Retrieval

PURPOSE

The technical success and safety of percutaneous inferior vena cava filters (IVCF) retrieval when filter elements are penetrating into adjacent bony structures is unknown. Therefore, our purpose was to evaluate the technical success and safety of IVCF retrieval when filter elements are penetrating into adjacent bone.

MATERIALS AND METHODS

Using percutaneous IVCF retrievals from 2008 to 2018 in adult patients, we conducted a multi-institutional, retrospective review of filters found to penetrate lumbar vertebrae by computed tomography scans. Technical success following the retrieval procedure was recorded. Patient records were assessed for complications from retrieval.

RESULTS

13 patients (2 males; 11 females; mean age: 53.2 years (range: 22-71) were included. Hundred percent of the filters were optional (retrievable) filters. Venous thromboembolism (VTE) with a contraindication to anticoagulation (n = 7; 53.8%) and prophylaxis without venous thromboembolism (n = 3; 23.1%) were the 2 most common indications for IVCF placement. Two filters (15.4%) had >15° of tilt relative to the IVC prior to retrieval while no IVCFs had migrated or caused caval thrombosis. One filter (7.7%) was found to have a fractured strut prior to retrieval. Ten patients (76.9%) were either on anticoagulants or antiplatelet medications at the time of retrieval. No patients were on antibiotics and no patients received periprocedural antibiotics. Median dwell time was 116.5 days (range: 49-5395). All 13 IVCFs were successfully retrieved in a single session (technical success: 100%). Standard snare technique was used in 8 cases (61.5%), endobronchial forces were used in 3 cases (23.1%), and wire loop snare technique was used in 2 cases (15.4%). There were no complications in any patient. Percutaneous retrieval of IVCFs with elements that have penetrated into adjacent vertebrae is both safe and technically feasible.

Inferior vena cava filter – comprehensive overview of current indications, techniques, complications and retrieval rates

Summary: Inferior vena cava (IVC) filter has been used to manage patients with pulmonary embolism and deep venous thrombosis. Its ease of use and the expansion of relative indications have led to a dramatic increase in IVC filter placement. However, IVC filters have been associated with a platitude of complications. Therefore, there exists a need to examine the current indications and identify the patient population at risk. In this paper, we comprehensively reviewed the current indications and techniques of IVC filter placement. Further, we examined the various complications associated with either permanent or retrievable IVC filters. Lastly, we examined the current data on filter retrieval.

Society of Interventional Radiology Clinical Practice Guideline for Inferior Vena Cava Filters in the Treatment of Patients with Venous Thromboembolic Disease: Developed in collaboration with the American College of Cardiology, American College of Chest Physicians, American College of Surgeons Committee on Trauma, American Heart Association, Society for Vascular Surgery, and Society for Vascular Medicine

PURPOSE

To provide evidence-based recommendations on the use of inferior vena cava (IVC) filters in the treatment of patients with or at substantial risk of venous thromboembolic disease.

MATERIALS AND METHODS

A multidisciplinary expert panel developed key questions to address in the guideline, and a systematic review of the literature was conducted. Evidence was graded based on a standard methodology, which was used to inform the development of recommendations.

RESULTS

The systematic review identified a total of 34 studies that provided the evidence base for the guideline. The expert panel agreed on 18 recommendations.

CONCLUSIONS

Although the evidence on the use of IVC filters in patients with or at risk of venous thromboembolic disease varies in strength and quality, the panel provides recommendations for the use of IVC filters in a variety of clinical scenarios. Additional research is needed to optimize care for this patient population.

Inferior Vena Cava Filters: Past, Present, and Future

Inferior vena cava (IVC) filters have existed as a treatment option for VTE for decades. Advances in medical technology have provided physicians with several options for devices that can be placed on either a permanent or temporary basis; however, there are limited data from randomized, controlled trials on the appropriate use of IVC filters. This contemporary review summarizes the history of IVC filters and the types that are available in clinical practice. It reviews the literature on the use of IVC filters and discusses the indications that professional societies have endorsed for their use. In addition, it outlines the complications of IVC filter placement and future research directions.

Incomplete opening of an ALN-type inferior vena cava filter due to entanglement of the filter legs resulting in filter migration and inferior vena cava perforation

Incomplete filter opening, causing filter migration and inferior vena cava (IVC) perforation, have often been observed with the Greenfield-type IVC filter, but reports of incomplete opening of the ALN-type IVC filter are extremely rare. We present herein the case of incomplete opening of an ALN-type IVC filter due to entanglement of the filter legs, which caused filter migration, IVC wall perforation, and penetration into the kidney and iliopsoas muscle. Successful percutaneous retrieval was performed without complications. Our experience provides guidance for similar situations in the future, including the need to check for complete filter opening.

Contemporary management of chronic indwelling inferior vena cava filters

OBJECTIVE

Despite increasing retrieval rates of the inferior vena cava (IVC) filter, less than one-third are removed within the recommended timeline. Prolonged filter dwell times may increase the technical difficulty of retrieval and filter-related complications. We sought to evaluate the contemporary outcomes of patients with chronic indwelling IVC filters at a tertiary care center.

METHODS

A retrospective analysis was performed from August 2015 through August 2019 of all patients who were referred for removal of a prolonged IVC filter with a dwell time >1 year. Descriptive analysis was used to evaluate patients' characteristics and procedural outcomes, which were reviewed through electronic medical records. Data were expressed as median with interquartile range (IQR) or number and percentage, as appropriate.

RESULTS

A total of 47 patients were identified with a median filter dwell time of 10.0 years (IQR, 6-13 years); 34 patients underwent IVC filter removal, and 13 patients refused retrieval. The median age of patients was 54.9 years (IQR, 42.5-64.0 years); the majority were female (57%) and white (53%). The most common indication for filter placement was high risk despite anticoagulation (49%), followed by venous thromboembolism prophylaxis (21%). The majority of patients were symptomatic (72%). If symptomatic, the most common reason for retrieval was IVC penetration (94%), and the chief complaint was pain (56%). Retrieval success was 97%, with a median length of stay of 0 days. The majority of retrievals were performed through an endovascular approach (97%). There was one postprocedural complication (3%).

CONCLUSIONS

Despite prolonged dwell times, IVC filter retrieval can be performed safely and effectively in carefully selected patients at a tertiary referral center.

Advancing structured decision-making in drug regulation at the FDA and EMA

The recent benefit-risk framework (BRF) developed by the Food and Drug Administration (FDA) is intended to improve the clarity and consistency in communicating the reasoning behind the FDA's decisions, acting as an important advancement in US drug regulation. In the PDUFA VI implementation plan, the FDA states that it will continue to explore more structured or quantitative decision analysis approaches; however, it restricts their use within the current BRF that is purely qualitative. By contrast, European regulators and researchers have been long exploring the use of quantitative decision analysis approaches for evaluating drug benefit-risk balance. In this paper, we show how quantitative modelling, backed by decision theory, could complement and extend the FDA's BRF to better support the appraisal of evidence and improve decision outcomes. After providing relevant scientific definitions for benefit-risk assessment and describing the FDA and European Medicines Agency (EMA) frameworks, we explain the components of and differences between qualitative and quantitative approaches. We present lessons learned from the EMA experience with the use of quantitative modelling and we provide evidence of its benefits, illustrated by a real case study that helped to resolve differences of judgements among EMA regulators.

Spanish multicenter real - life registry of retrievable vena cava filters (REFiVeC)

BACKGROUND

The treatment of venous thromboembolic disease the treatment of choice is systemic anticoagulation. However, the interruption of the inferior vena cava with filters has been recommended when anticoagulation fails or there is a contraindication. Due to the rising inferior vena cava filter (IVCF) complications, physicians are encouraged to retrieve them when there is no longer recommended. In daily practice, it may be a difficult close follow-up of these patients. In this study, the primary objective was to evaluate the IVCF retrieval rate of all implanted filters in a Spanish registry. Secondary objectives were to analyze the causes of failed retrieval, procedure-related complications, and outcomes at a 12-month follow-up.

RESULTS

Three hundred fifty-six vena cava filters were implanted in 355 patients. The types of filter were: Gunther Tulip (Cook Medical) 160 (44.9%), Optease (Cordis) 77 (21.6%), Celect (Cook Medical) 49 (13, 7%), Aegisy (Lifetech Scientific) 33 (9.2%), Option ELITE (Argon Medical devices) 16 (4.4%), Denali filter (BD Bard) 11 (3.08%), ALN filter (ALN) 10 (2.8%). Removal was achieved in 274/356 (76,9%). eighty-two (23,1%) IVCF were not retrieved due to the following: 41 (11,5%) patients required ongoing filtration, 24 IVCF (6,7%) patients died before retrieval, and 17 (4,7%) impossibility of retrieval because of a tilted and embedded filter apex. There were no major complications observed.

CONCLUSIONS

The global retrieval rate of IVCF was achieved in 76.9%, and the adjusted retrieval rate was of 94.15% with no major complications. IVCF tilting was associated with failure of filter removal in less than 5% of cases. This study demonstrates that the retrieval procedure of IVCF is controlled by the clinician and not by the interventional radiologist.

Permanent inferior vena cava filters offer greater expected patient utility at lower predicted cost

OBJECTIVE

Retrievable inferior vena cava (IVC) filters were first approved for use in the United States in 2003 to address the long-term complications of migration, thrombosis, fracture, and perforation observed with permanent IVC filter implantation. Although Food and Drug Administration approval of retrievable IVC filters includes permanent implantation, the incidence of complications from long-term implantation appears to be greater than that reported with existing permanent IVC filters. Also, only a small fraction of such retrievable IVC filters are ever retrieved. The purpose of the present study was to determine the threshold retrieval rate at which the use of retrievable IVC filters could be justified.

METHODS

A Markov decision tree was constructed comparing retrievable and permanent IVC filters regarding their effectiveness and cost. A review of the reported data provided outcome probabilities, and the Tufts Medical Center Cost-Effectiveness Analysis Registry was the source of the utility values for the various potential outcomes. Medicare reimbursement rates served as a proxy for costs. A sensitivity analysis was performed for various parameters, primarily to determine the retrieval rate threshold at which the use of retrievable IVC filters would outperform the use of permanent IVC filters.

RESULTS

Base case analysis demonstrated a greater predicted effectiveness for permanent compared with retrievable IVC filter implantation (5.41 quality-adjusted life-years [QALY] vs 5.33 QALY) at a lower cost ($2070 vs $4650). Monte Carlo simulation at 10,000 iterations confirmed the expected utility (5.4 ± 3.0 QALY vs 5.3 ± 3.0 QALY; P = .0002) and cost ($1900 ± $7400 vs $4800 ± 9900; P < .0001) to be statistically superior for permanent IVC filters. A sensitivity analysis for the filter retrieval rate demonstrated that the strategy of using a retrievable IVC filter was never preferable for utility or cost. The superiority of permanent IVC filter placement for effectiveness and cost persisted, regardless of anticipated patient-predicted annual mortality. A two-way sensitivity analysis for both IVC filter removal rate and annual patient mortality confirmed the superiority of permanent IVC filter placement at all levels.

CONCLUSIONS

The predicted effectiveness of permanent IVC filters was greater and the predicted cost lower than those for retrievable IVC filters, regardless of the IVC filter retrieval rate. This interpretation of existing reported data using Markov decision analysis modeling supports the argument that unless the long-term complication rate of retrievable IVC filters can be significantly improved, their use should be abandoned in favor of currently available permanent IVC filters.

Modified one-session endovascular treatment for deep venous thrombosis with high risk of pulmonary embolism: Short-term outcomes

OBJECTIVES

To evaluate the safety and short-term outcomes of the modified one-session endovascular treatment with inferior vena cava filter placement and retrieval in one stage for the treatment of acute lower extremity deep vein thrombosis.

METHOD

Twenty-three patients with unilateral acute lower extremity deep vein thrombosis underwent modified one-session endovascular treatments, which were performed in one stage. Inferior vena cava filter placement without detachment, thrombectomy, and inferior vena cava filter retrieval were performed in one stage. Angioplasty and stent implantation were performed for patients with iliac vein stenosis. Venography was performed to identify the clearance of the thrombus. Color Doppler ultrasound and/or venography were conducted during the follow-up.

RESULTS

A total of 20/23 (87%) patients with thrombus removal rate >90% successfully underwent modified one-session endovascular treatment. inferior vena cava filters were detached in 3/23 (13%) patients achieving 50%-90% thrombus removal rate. Twenty-one iliac vein stents were implanted in 21/23 (91%) patients with iliac vein stenosis. After treatment, the differences in the circumferences of the affected limb and the healthy limb both significantly decreased. No procedure-related death, symptomatic pulmonary embolism, or major bleeding occurred. During the 12-25 months of follow-up, iliac vein stents and lower extremity veins maintained patent.

CONCLUSIONS

The modified one-session endovascular treatment with one-stage inferior vena cava filter placement and retrieval might be safe for the treatment of acute lower extremity deep vein thrombosis, and the early clinical outcomes are satisfactory. Placing and retrieving an inferior vena cava filter in one session could safeguard the endovascular interventions as well as reduce the filter-related complications associated with long dwelling times.

Successful multi-step catheter intervention for thrombotic inferior vena cava filter retrieval

A 45-year-old man, who was implanted with an inferior vena cava (IVC) filter in his infrarenal IVC, had a complication of deep vein thrombosis (DVT) propagation from the IVC, beyond the IVC filter, to the right calf and left external iliac veins. The entire IVC filter was covered with a massive thrombus. We first decided to retrieve the IVC filter itself, which was suspected of causing metallic allergy. The thrombotic IVC filter was successfully retrieved using multi-step catheter intervention. To our knowledge, this is the first case report to describe successful multi-step catheter intervention for retrieval of an IVC filter covered with a massive thrombus. <Learning objectives: Inferior vena cava (IVC) filter thrombosis is one of the most serious IVC filter complications. It is difficult to retrieve the IVC filter covered with a massive thrombus. Multi-step catheter intervention technique may be useful to retrieve an IVC filter with thrombotic occlusion.>.