Supply Costs in Complex and Routine Inferior Vena Cava Filter Retrieval: 10 Years' Data from a Single Center

PURPOSE

To characterize the medical supply costs associated with inferior vena cava filter retrieval (IVCFR) using endobronchial forceps (EFs), a snare, or Recovery Cone (RC).

MATERIALS AND METHODS

In total, 594 of 845 IVCFRs attempted at a tertiary referral hospital between October 1, 2012, and June 20, 2022 were categorized by intended retrieval strategy informed by, rotational cavography as follows: (a) EF (n = 312) for tilted or tip-embedded/strut-embedded filters and for long-dwelling closed-cell filters and (b) a snare (n = 255) or (c) RC (n = 27) for other well-positioned filters with or mostly without hooks, respectively. List prices of relevant supplies at time of retrieval were obtained or, rarely, estimated using a standard procedure. Contrast use, fluoroscopic time, filter type, dwell time, and patient age and sex were recorded. Mean between-group cost differences were estimated by linear regression, adjusting for date. Additional models evaluated filter type, dwell time, and patient-level effects.

RESULTS

Of the 594 IVCFRs, 591 were successful, whereas 2 EF and 1 snare retrievals failed. Moreover, 4 EF retrievals were successful with a snare and 2 with smaller EF, 12 snare retrievals were successful with EF, 1 RC retrieval was successful with a snare and 2 with EF. Principal model indicated a significantly lower mean cost of EF ($564.70, SE ± 9.75) than that of snare ($811.29, SE ± 10.83; P < .0001) and RC ($1,465.48, SE ± 47.12; P < .0001) retrievals. Adjusted models yielded consistent results. Had all retrievals been attempted with EF, estimated undiscounted full-period supplies savings would be $87,201.51.

CONCLUSIONS

EFs are affordable for complex IVCFR, and extending their use to routine IVCFR could lead to considerable cost savings.

Successful retrieval of tip-embedded inferior vena cava filter using a modified forceps technique: case report

BACKGROUND

The retrieval of inferior vena cava (IVC) filter is essential for preventing complications associated with the device. Advanced techniques have been developed to improve the success rate of retrieving tip-embedded filters. The forceps technique is frequently used to address this issue.

CASE PRESENTATION

We present a case study of two patients who underwent a successful tip-embedded IVC filter retrieval using a modified forceps technique, which has not been previously reported. This technique involves using a wire loop under the filter tip and a forceps to grasp the filter shoulder. By pulling the wire loop and pushing the forceps in counterforce, the filter tip is straightened and aligned with the vascular sheath. The vascular sheath can then dissect the filter tip out from the caval wall and get inside the sheath to complete the retrieval.

CONCLUSIONS

The modified forceps technique we present here offers a new solution for the complex retrieval of IVC filters.

The development of a novel endovascular grasper for challenging inferior vena cava filter retrieval

OBJECTIVE

Although inferior vena cava (IVC) filters are commonly retrieved using a snare, lateral tilt and fibrosis around struts can complicate the procedure and sometimes require the use of off-label devices. We describe the development of a novel articulating endovascular grasper designed to remove permanent and retrievable IVC filters in any configuration.

METHODS

For in vitro testing, the IVC filters were anchored to the inner wall of a flexible tube in a centered or tilted configuration. A high-contrast backlit camera view simulated the two-dimensional fluoroscopy projection during retrieval. The time from the retrieval device introduction into the camera field to complete filter retrieval was measured in seconds. The control experiment involved temporary IVC filter retrieval with a snare. There were four comparative groups: (1) retrievable filter in centered configuration; (2) retrievable filter in tilted configuration; (3) permanent filter in centered configuration; and (4) permanent filter in tilted configuration. Every experiment was repeated five times, with median retrieval time compared with the control group. For in vivo testing in a porcine model, six tilted infrarenal IVC filters were retrieved with grasper via right jugular approach. Comparison analysis between animal and patient procedures was performed for the following variables: total procedure time, the retrieval time, and fluoroscopy time.

RESULTS

The in vitro experiments showed comparable retrieval times between the experimental groups 1, 2, and 4 and the control. However, grasper removal of a centered permanent filter (group 3) required significantly less time than in the control (29 vs 79 seconds; P = .009). In the animal model, all IVC filters were retrieved using the grasper with no adverse events. The total procedure time (21.2 vs 43.5 minutes; P = .01) and the fluoroscopy time (4.3 vs 10 minutes; P = .044) were significantly shorter in the animal model compared with the patient group. Moreover, in the patient group, 16.7% of retrievals required advanced endovascular techniques, and one IVC filter could not be retrieved (success rate = 91.7%), whereas all the IVC filters were successfully retrieved in the animal model without the use of additional tools.

CONCLUSIONS

The novel endovascular grasper is effective in retrieving different types of IVC filters in different configurations and compared favorably with the snare in the in vitro model. In vivo experiments demonstrated more effective retrieval when compared with matched patient retrievals.

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.

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.

Inferior vena cava filter retrievals using advanced techniques: a systematic review

This study aimed to assess the safety of complex inferior vena cava (IVC) filter retrieval techniques through a systematic review of published literature. Using PubMed, a systematic review was conducted in line with the 2020 Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines to identify articles published through April 2020 that reported on complex IVC filter retrieval techniques in >5 patients. Case reports, review papers, and studies that did not report on primary outcomes or variables of interest were excluded. Risk of bias was assessed using a modified Newcastle-Ottawa Quality Assessment scale. Pooled success and complication rates were calculated for the overall number of complex retrieval attempts as well as for each filter type and each complex retrieval method. Sixteen fair-quality and three good-quality studies met the inclusion criteria, with 758 patients (428 female) who had undergone 770 advanced retrieval attempts. The mean age of the patients was 46.5 ± 7.1 years (range: 14.1-90), and the mean dwell time was 602.5 ± 388.6 days (range: 5-7336). Regarding filters, 92.6% (702/758) were retrievable and 7.4% (56/758) were permanent. Indications for complex retrieval included the failure of standard retrieval (89.2%; 676/758) and tilting or embedding in the caval wall (53.8%; 408/758); 92.6% (713/770) of the advanced retrieval attempts were successful. The pooled success rate was 92.0% (602/654) for retrievable filters and 96.4% (53/55) for permanent filters (P = 0.422). Only 2.8% (21/758) of patients experienced major complications, and the major complication rate was not significantly associated with filter type (P = 0.183). Advanced techniques for IVC filter retrieval appear safe for the retrieval of retrievable filters and certain permanent filters, with a low short-term major complication rate. Further studies on complex retrieval techniques used to remove permanent filters should be conducted to clarify their safety with respect to filter type.

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.

Grasp-and-Fold Technique for Complex Inferior Vena Cava Filter Retrieval

This study evaluated the use of the grasp-and-fold technique for complex forceps retrieval of inferior vena cava (IVC) filters. A retrospective study of 14 patients (12 women and 2 men) who had either deeply tip-embedded or severely distorted IVC filters was performed at a single institution over 10 years. In this technique, endobronchial forceps were used to fold the filter in half to remove it through the sheath because the filter tip could not be accessed by dissection. The grasp-and-fold technique successfully removed all 14 filters. One patient had retained filter struts, which were present before the procedure. One mild and 5 moderate adverse events (AEs), including fracture fragment embolization requiring retrieval and self-limited IVC extravasation, occurred. No severe AEs occurred. In this small patient cohort, the grasp-and-fold forceps technique successfully retrieved deeply tip-embedded or distorted IVC filters with inaccessible tips.

Endobronchial Forceps Retrieval of Embedded Inferior Vena Cava Filters: Retrieval of 535 Filters at a Single Center

PURPOSE

To report results of 16 years of using the endobronchial forceps technique to remove embedded inferior vena cava (IVC) filters.

MATERIALS AND METHODS

Between January 2005 and June 2021, 534 patients (310 women and 224 men) with a mean age of 52 years (standard deviation [SD] ± 16 years) presented for complex filter retrieval of 535 tip- or strut-embedded IVC filters. Tip-embedded filters were diagnosed on rotational venography. Filters were considered strut-embedded if they were closed-cell filters with dwell times of >6 months. The filter was dissected from the IVC using rigid bronchoscopy forceps and removed through a vascular sheath.

RESULTS

The endobronchial forceps technique was successful in 530 of 537 retrieval attempts on an intention-to-treat basis (98.7%); a total of 530 filters were retrieved. There were 7 failures: (a) 5 failed retrieval attempts (2 that were retrieved successfully in subsequent procedures) and (b) 2 for which retrieval was not attempted. The mean filter dwell time was 1,459 days (SD ± 1,617 days). Laser sheaths were not used for any removal. Filters included herein were 137 Celect (94 Celect and 43 Celect Platinum), 99 Günther Tulip, 72 Option (48 Option and 24 Option Elite), 68 G2, 45 G2X/Eclipse, 42 Denali, 30 OptEase, 29 Recovery, 7 Meridian, and 6 ALN with Hook filters. Thirty-four minor (6.3%) and 11 major (2%) adverse events (AEs) occurred, which did not result in permanent sequelae.

CONCLUSIONS

Use of endobronchial forceps for removal of tip- and strut-embedded retrievable IVC filters is effective and has low AE rates.

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.

Rigid forceps and excimer laser use for complex inferior cava filter retrieval: a preliminary quantitative analysis of available evidence

Purpose

The present study aims to evaluate the safety and efficacy of advanced inferior vena cava filter (IVCF) retrieval using laser assistance compared with forceps via systematic review and quantitative aggregation of available data.

Methods

Pubmed and Embase were queried from establishment to September 2021. Original studies with a sample size ≥ 5 that reported at least one primary outcome of patients who underwent laser- or forceps-assisted IVCF retrieval were included. Primary outcomes included technical success and complication rates. Baseline characteristics were extracted: age, sex, presence of filter thrombus, strut penetration, previous retrieval attempt, filter dwell time, fluoroscopy time, and filter type. Complications were categorized by type and severity. Categorical data was pooled and evaluated with chi-square or Fisher exact tests.

Results

From the 16 included studies, a total of 673 and 368 patients underwent laser- and forceps-assisted IVCF retrieval, respectively. Successful retrieval was achieved in 98.1 and 93.7% patients from the laser and forceps groups, respectively (p < 0.001). Major complication rates (1.6 vs 2.1%, p = 0.629) and risk of injury to cava or adjacent organs (1.0 vs 1.4%, p = 0.534) were similar between the two groups. A higher proportion of filters from the laser arm were closed-cell design (75.4 vs 68.1%, p = 0.020).

Conclusion

Based on limited available evidence, forceps- and laser-assisted complex IVCF retrievals were equally safe. The use of laser sheath is associated with a higher retrieval rate than forceps alone, though the baseline characteristics of two cohorts were not controlled. Future large-scale case-controlled comparative studies with longer clinical follow-up are warranted.

Supplementary Information

The online version contains supplementary material available at 10.1186/s42155-022-00311-4.

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.

Complex filter removal using forceps from combined transfemoral and transjugular approach unhooking the filter apex using forceps and dual access: Two case reports

Modern inferior vena cava filters (IVCFs) are intended to be retrieved once a thrombotic process or risk of pulmonary embolism has resolved independent of administration of anticoagulation. IVCF removal can be challenging with the risk of complications including venous perforation, filter migration, and device fracture. IVCF removal has been described using the nomenclature of routine versus advanced retrieval. Routine retrieval is defined as accessing the filter hook with a loop snare device before advancing a sheath over the filter. Advanced retrieval techniques are employed when routine retrieval fails and can refer to a variety of approaches, including filter realignment with loop snare, stiff wire-displacement, use of a wire and snare with dual access, angioplasty balloon advanced over a guidewire, single access sling approach, the sandwich technique, the endobronchial forceps dissection and removal, photothermic ablation with excimer laser, and the filter eversion technique among others. Successful routine retrieval of IVCF has been reported at 74% and IVCF retrieval with advanced techniques has a success rate of nearly 95%. The complication rate with advanced techniques is higher when compared with routine techniques (5.3% vs. 0.4%; p < .05) and, as expected, requires fluoroscopic time. We report two cases of advanced filter retrieval using endobronchial forceps simultaneously or sequentially through the transfemoral and trans-jugular approach.

Classification System for Inferior Vena Cava (IVC) Appearance Following Percutaneous IVC Filter Retrieval

OBJECTIVE

There is no classification system for describing inferior vena cava (IVC) injuries. The objective of this study was to develop a standardized grading system for venographic appearance of the IVC following percutaneous IVC filter retrieval.

METHODS

A classification system for the appearance of the IVC on cavograms following percutaneous IVC filter removal was developed consisting of two grading elements; luminal characteristics and extravasation. Luminal narrowing from 0% up to 50% from any cause is grade 1; narrowing between 50 and 99% is grade 2; occlusion is grade 3; and avulsion is grade 4. Absence of extravasation is grade A, contained extravasation is grade B, and free extravasation is grade C. This system was then applied retrospectively to pre- and post-IVC filter retrieval cavograms performed at a single institution from October 2004 through February 2019.

RESULTS

546 retrieval attempts were identified with 509 (93.2%) filters successfully retrieved. 449 cases (88.2%) had both pre-retrieval and post-retrieval imaging appropriate for application of the proposed classification system. Inter-rater reliability was 0.972 for luminal characteristics, 0.967 for extravasation, and 0.969 overall. Consensus grading demonstrated a distribution of 97.3% grade 1, 1.3% grade 2, 1.3% grade 3, and 0.0% grade 4 for post-retrieval luminal characteristics. For extravasation classification, 96.4% of the cases were classified as grade A, 2.7% grade B, and 0.9% grade C.

CONCLUSION

A classification system was developed for describing IVC appearance after IVC filter retrieval, and retrospectively validated using a single center dataset.

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.

Biopsy Forceps-Assisted Loop Snare Technique for Complex Retrieval of Inferior Vena Cava Filter

Severe tilt with embedded hooks is a common obstacle to successful inferior vena cava (IVC) filter retrieval. We present a case for which the biopsy forceps-assisted loop snare technique was successfully used to retrieve filters with hooks embedded in the IVC wall for which conventional retrieval failed. The technique is effective and provides a less-invasive, low-cost method for the complex retrieval of IVC filters.

Comparative efficacy and safety of the Captus device for inferior vena cava filter retrieval

PURPOSE

Retrievable inferior vena cava filters (IVCF) have been increasingly used for mechanical pulmonary embolism prophylaxis since their development. The Captus Vascular Retrieval System (Avantec Vascular, Sunnyvale, California) is a new device developed for retrieval of IVCF. This study compared the safety and efficacy of the new Captus device against the existing EnSnare Endovascular Snare System (Merit Medical, South Jordan, Utah) for IVCF retrieval.

METHODS

Patients undergoing IVCF retrieval at a single institution between July 2015 and July 2020 were retrospectively identified. All adult patients (>18 years) undergoing filter retrieval with either Captus or Ensnare were included. Technical success and complications were compared by device. A complexity score was assigned to each case to adjust for selection bias. Logistic regression was used to model the association between device type and primary technical success.

RESULTS

99 IVCF retrievals met inclusion criteria, 59 with Captus and 40 with Ensnare. The majority of the cohort consisted of low complexity cases (n = 51, 86% Captus versus n = 31, 78% Ensnare; p = 0.28). Technical success for low and medium complexity retrievals was 88% and 62% with Captus and 96% and 33% with Ensnare. There was no significant association between device type and technical success, adjusting for case complexity (Captus OR 0.55, 95% CI 0.08-2.72, p = 0.49). There were no device-related complications.

CONCLUSION

No statistically significant difference in device technical success or complications between the Ensnare and Captus devices for uncomplicated IVCF retrieval.

PRECIS

The Captus Vascular Retrieval System is a new device for IVC filter retrieval which has similar technical success to the existing EnSnare.

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.

Current Controversies in Inferior Vena Cava Filter Placement: AJR Expert Panel Narrative Review

Despite inferior vena cava (IVC) filter practice spanning over 50 years, interventionalists face many controversies in proper utilization and management. This article reviews recent literature and offers opinions on filter practices. IVC filtration is most likely to benefit patients at high risk of iatrogenic pulmonary embolus during endovenous intervention. Filters should be used selectively in patients with acute trauma or who are undergoing bariatric surgery. Retrieval should be attempted for perforating filter and fractured filter fragments when imaging suggests feasibility and favorable risk-to-benefit ratio. Antibiotic prophylaxis should be considered when removing filters with confirmed gastrointestinal penetration. Anticoagulation solely because of filter presence is not recommended except in patients with active malignancy. Anticoagulation while filters remain in place may decrease long-term filter complications in these patients. Patients with a filter and symptomatic IVC occlusion should be offered filter removal and IVC reconstruction. Physicians implanting filters may maximize retrieval by maintaining physician-patient relationships and scheduling follow-up at time of placement. Annual follow-up allows continued evaluation for removal or replacement as appropriate. Advanced retrieval techniques increase retrieval rates but require caution. Certain cases may require referral to experienced centers with additional retrieval resources. The views expressed should help guide clinical practice, future innovation, and research.

Percutaneous Extraction of an Embolized IVC Filter Strut Embedded in the Right Ventricle

The incidence of IVC filter fracture is high with risk for embolization and may require open surgery. We present a minimally invasive approach of complex transcatheter extraction of an embolized and embedded IVC filter strut from the right ventricle. (Level of Difficulty: Intermediate.)

Caval pseudoaneurysms following complex inferior vena cava filter removal: Clinical significance and patient outcomes

OBJECTIVES

To investigate the incidence and clinical significance of caval pseudoaneurysm and extravasation post-complex inferior vena cava filter retrieval.

METHODS

A total of 83 patients (70% female, average age 56) underwent complex inferior vena cava filter retrieval between January 2015 and December 2019 utilizing either rigid endobronchial forceps (n = 69, 83%) and/or excimer laser (n = 20, 24%). Procedural variables were recorded. The incidence and size of caval pseudoaneurysms and extravasation along with treatment type and clinical outcomes were analyzed.

RESULTS

Technical success in all cases was 96% (n = 80). Average fluoroscopy time was 23 min (median: 20.2, range: 0.9-129.5). Average filter dwell time was 85 months (range: 2-316 months). Caval pseudoaneurysm was detected on post-retrieval venography in 10 patients (12%) and frank extravasation occurred in 1 case (1%). Average pseudoaneurysm length and width was 20.4 mm (range: 5-45 mm) and 12.9 mm (range: 4-24 mm), respectively. Pseudoaneurysms occurred most frequently during the removal of Optease (n = 5) and Celect (n = 2) filters. The pseudoaneurysms completely resolved with prolonged (>5 min) balloon angioplasty in all but one instance where a small portion of the pseudoaneurysm persisted. This patient was admitted and observed overnight before being discharged without complication. The solitary case of significant extravasation was effectively managed with immediate stent placement and the patient remained hemodynamically stable.

CONCLUSIONS

Radiographically detectable caval pseudoaneurysm and extravasation is not uncommon in complex inferior vena cava filter retrieval and, despite being considered a major complication by Society of Interventional Radiology guidelines, can often be managed without stenting or other invasive treatment.

Excimer Laser Sheath-Assisted Retrieval of "Closed-Cell" Design Inferior Vena Cava Filters

Background Numerous reports have shown that inferior vena cava filters are associated with clinically significant adverse events. Complicating factors, such as caval incorporation, may lead to technical challenges at retrieval. The use of advanced techniques including the laser sheath have increased technical success rates; however, the data are limited on which filter types necessitate and benefit from its use. Methods and Results From October 2011 to September 2019, patients with inferior vena cava filter dwell times >6 months or with prior failed retrievals were considered for laser sheath-assisted retrieval. Standard and nonlaser advanced retrieval techniques were attempted first; if the filter could not be safely or successfully detached from the caval wall using these techniques, the laser sheath was used. Technical success, filter type, necessity for laser sheath application based on "open" versus "closed-cell" filter design, dwell times, and adverse events were evaluated. A total of 441 patients (216 men; mean age, 54 years) were encountered. Mean dwell times for all filters was 56.6 months, 54.4 among closed-cell filters and 58.5 among open-cell filters (P=0.63). Technical success of retrieval was 98%, with the laser sheath required in 143 cases (40%). Successful retrieval of closed-cell filters required laser sheath assistance in 60% of cases as compared with 7% of open-cell filters (odds ratio, 20.1; P<0.01). In closed-cell inferior vena cava filters, dwell time was significantly associated with need for laser, requiring it in 64% of retrievals with dwell times >6 months (P=0.01). One major adverse event occurred among laser sheath retrievals when a patient required a 2-day inpatient admission for a femoral access site hemorrhage. Conclusions Closed-cell filters may necessitate the use of the laser sheath for higher rates of successful and safe retrieval.

Procedural complications of inferior vena cava filter retrieval, an illustrated review

Annually, approximately 65,000 inferior vena cava (IVC) filters are placed in the United States (Ahmed et al., J Am Coll Radiol 15:1553-1557, 2018). Approximately 35% of filters are eventually retrieved (Angel et al., J Vasc Interv Radiol 22: 1522-1530 e1523, 2011). Complications during filter retrieval depend heavily on technique and filter position. In this paper, we review risk factors and incidence of complications during IVC filter removal. We also discuss ways these complications could be avoided and the appropriate management if they occur.

Over-the-wire deployment techniques of option elite inferior vena cava filter: 3D printing vena cava phantom study

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Bent stiff-wire technique with transfemoral access had lower filter tilt ratio at Option IVC filter deployment.

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Original push wire with transjugular access had lower filter tilt ratio at Option IVC filter deployment.

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Filter jumping was common using the original push wire with transjugular access.

Purpose

To compare filter tilt and filter jumping during Option inferior vena cava (IVC) filter deployment with 3 different wires techniques using a 3-dimensional (3D) printing vena cava phantom.

Materials and methods

An IVC 3D printed vena cava phantom was made from a healthy young male’s computed tomographic data. Option IVC filters were deployed with 3 different wires: i) original push wire, ii) hydrophilic stiff wire, and iii) bent stiff wire. Right internal jugular and right femoral access were used 5 times with each wire. Filter tilt angle, tilt ratio, jumping, and tip abutment to the IVC wall were analyzed.

Results

The transfemoral approach with original push wire had significantly higher tilt angle than did the transjugular approach (6.1˚ ± 1.9 vs. 3.5˚ ± 1.3, p = 0.04). Mean tilt ratio was significantly lower with the bent wire with transfemoral access (0.49 ± 0.13 vs. 0.78 ± 0.18 [original push-wire] and 0.67 ± 0.08 [stiff wire], p = 0.019). The ratio was lower also with original push wire with transjugular access (0.34 ± 0.19 vs. 0.57 ±0.11 [stiff wire] and 0.58 ±0.17 [bent wire], p = 0.045). Filter jumping occurred more often with the transjugular approach with original push wire than with stiff or bent-wire delivery. Filter tip abutment to the IVC wall occurred only with the transfemoral approach.

Conclusions

Bent wire with transfemoral access and original push wire with transjugular access had lower filter tilt ratio at Option IVC filter deployment. However, filter jumping was common using the original push wire with transjugular access.

Magnification Spot Radiographs Improve Assessment for Inferior Vena Cava Filter Fractures prior to Removal Compared to CT

PURPOSE

To determine if magnification spot radiographs acquired before attempting inferior vena cava (IVC) filter removal have value in the assessment for filter fractures.

MATERIALS AND METHODS

A retrospective review of complex IVC filter removals performed at a tertiary referral center from October 2015 to May 2017 was performed. Magnification spot radiographs (frontal and at least 2 oblique views) were obtained with the fluoroscopic unit in the procedure suite prior to venous access for filter removal. Patients were included in the study if a computed tomography (CT) scan of the abdomen/pelvis before filter removal was available. Ninety-six patients (47 women and 49 men) were included. Most removed filters were the Recovery/G2/G2X/Eclipse/Meridian (n = 28), the Günther Tulip (n = 26), and the Celect/Celect Platinum (n = 22). Blinded review of the pre-procedural CT scans and spot radiographs for the presence of filter fractures was performed by 2 interventional radiologists. Accuracy of each modality was assessed using the status of the explanted filter as the gold standard. Agreement between the 2 readers was assessed with the kappa statistic.

RESULTS

Fractures were present in 27 explanted filters (28%). Accuracy of CT was 88% and 68% for readers 1 and 2, respectively, which increased to 98% and 97% with magnification spot radiographs. The kappa statistic was 0.12 for CT and 0.97 for spot radiographs.

CONCLUSIONS

Magnification spot radiographs acquired before attempting IVC filter removal improve detection of filter fractures and agreement among interventional radiologists. Therefore, these should be performed routinely to allow for optimal treatment planning.

A Single-Institutional Comparative Analysis of Advanced Versus Standard Snare Removal of Inferior Vena Cava Filters

PURPOSE

To investigate differences in procedure time, radiation exposure, and periprocedural complications associated with advanced inferior vena cava (IVC) filter retrieval compared with standard snare retrieval.

MATERIALS AND METHODS

A total of 378 patients underwent standard or advanced IVC filter retrieval over a 5-year period. Technical success, retrieval techniques, fluoroscopy time, radiation dose, and complications were analyzed. All retrieval procedures with techniques other than a "snare-and-sheath" method were categorized as advanced, including failed standard attempts requiring intraprocedural conversion to advanced techniques.

RESULTS

A total of 462 filter retrieval attempts were made in 378 patients (57% female). Success rates for standard and advanced retrieval attempts were 86.8% (317 of 365) and 91.8% (89 of 97), respectively. The rate of periprocedural complications was significantly higher in the advanced retrieval group (P = .006). Complication rates for standard and advanced retrievals were 0.6% (2 of 318; all minor) and 5.2% (5 of 97; 3 minor [3.1%] and 2 major [2.1%]), respectively. The 2 major complications during advanced retrievals included filter fracture and embolization. Average fluoroscopy time for advanced retrievals was significantly higher than for standard retrievals (23.1 min vs 4.3 min; P < .001). Average radiation dose for advanced retrievals was also significantly higher than for standard retrievals (557.2 mGy vs 156.9 mGy; P < .001). Use of general anesthesia was also significantly more common in advanced retrievals compared with standard retrievals (6.2% vs 0.9%; P = .002).

CONCLUSIONS

Advanced filter retrieval results in a similarly high rate of technical success compared with standard snare retrieval but is associated with greater fluoroscopy time, anesthesia requirements, and radiation exposure.

Forceps-assisted Removal of Difficult-to-Retrieve Filters: Preliminary Results

BACKGROUND

The aim of this study is to retrospectively evaluate the safety and effectiveness of forceps-assisted removal of difficult-to-retrieve filters.

METHODS

Patients who underwent forceps-assisted removal of difficult-to-retrieve filters (filters that could not be successfully removed with the standard loop-snare technique) between February 2008 and February 2019 were included in this study. Patients underwent forceps-assisted filter removal either immediately after failed loop-snare removal (same procedure) or at a later time (separate procedure). Data regarding success rate, X-ray exposure time, and complications were recorded.

RESULTS

A total of 27 patients (14 men, 13 women; mean age 57.9 ± 12.6 years) were included in this study. The mean indwelling time of the filters was 10.9 ± 10.7 months. All filters were successfully removed. The mean X-ray exposure time was 25.9 ± 12.7 min (range 8-55) for all patients; the mean X-ray exposure times were 10.2 ± 2.3 min (range 8-14) for the 5 patients who underwent forceps-assisted filter removal in a separate procedure and 29.5 ± 11.2 min (range 15-55) for the 22 patients who underwent forceps-assisted filter removal immediately after failure of the loop-snare technique (P < 0.001). Two patients (8.3%) experienced extravasation of contrast material and needed no additional treatment. No major complications occurred.

CONCLUSIONS

Forceps-assisted filter retrieval can be used to safely and effectively remove difficult-to-retrieve filters.

Feasibility and Acute Safety Study of Radiofrequency Energy Delivery to the Vena Caval Wall via an IVC Filter in Swine

Retrievable inferior vena cava (IVC) filters are self-expanding metallic devices implanted in the IVC to prevent migration of thrombi from the deep veins of the legs and pelvis to the lungs. The risk of complications from the filters increases with duration of implantation, but retrieval may be difficult due to intimal hyperplasia around the components of the filter. In this study, the potential for delivery of radiofrequency (RF) energy to the IVC wall via the filter was investigated. IVC filters were deployed in 4 swine while attached to a snare connected to a 480 kHz RF generator. Energy ranging from 0 to 48 kJ was applied via the filter followed by re-sheathing and withdrawal of the filter while connected to a force measurement device. Resheathing forces for the 0-energy cohort and pooled data from the 6-24 kJ cohorts were 4.50±0.70 N and 4.50±0.75 N, respectively. Petechial hemorrhages and variable non-occlusive thrombi were noted in some cohorts including the 0-energy cohort, consistent with delivery and acute retrieval of an IVC filter. Histologically, the extent of RF-induced injury was subtle at 6 kJ with focal areas of homogenized collagen while the 12 kJ cohort showed segmental tissue charring with coagulation necrosis which was more extensive for the 24 kJ cohort. The 48 kJ energy caused more extensive and non-target organ damage. The study demonstrated feasibility of delivery of RF to the IVC wall via a deployed filter, supporting further study of the ability of local RF heating of the IVC wall to inhibit the neointimal hyperplasia or as an aid in retrieval.

A curious case of forceps delivery in IR

Self-expanding nitinol stents are routinely used to treat left common iliac vein compression in patients with May-Thurner syndrome. On occasion these stents do not provide adequate radial force to achieve a sufficient iliac lumen. If symptoms persist and persistent iliac vein compression is noted then balloon-expandable stents may be used to provide buttressing support at the compression site. We present a case where the buttressing balloon-expandable stent is crushed and subsequently removed percutaneously prior to placement of a high radial force self-expanding stent at the compressive site.

Single-session inferior vena cava filter removal, recanalization, and endovenous reconstruction for chronic iliocaval thrombosis

OBJECTIVE

The objective of this study was to demonstrate the safety and efficacy of treatment of inferior vena cava filter (IVCF)-related chronic iliocaval thrombosis with single-session IVCF retrieval and iliocaval recanalization, thereby optimizing stent deployment and avoiding adverse events (AEs) related to stent placement across an obstructed filter.

METHODS

From January 2015 to April 2018, a cohort of 25 consecutive patients presented for treatment of IVCF-related chronic iliocaval thrombosis with filter retrieval, followed by recanalization with stent placement and adjunctive iliofemoral thrombectomy as needed. Inclusion criteria included computed tomography (CT) imaging and clinical presentations consistent with chronic (>30 days) IVCF-related chronic thrombosis. A retrospective analysis of technical success, clinical success as measured with the Venous Clinical Severity Score, use of advanced filter retrieval techniques, and AEs was performed. Primary patency was evaluated with CT at 1 to 3 months and 1 year. Data analysis was performed using a paired t-test.

RESULTS

There were 25 patients (median age, 58.0 years; standard deviation, 15.6 years) with eight types of IVCF encountered; all were treated in a single session. Technical success was achieved in all patients. Mean improvement in the Venous Clinical Severity Score was 1.4 (95% confidence interval, 1.0-1.7; P < .01) in the venous edema subscore and 0.6 (95% confidence interval, 0.2-1.0; P < .01) in the pain subscore. At 1 to 3 months, iliocaval stent patency was maintained in 96% of patients; unilateral iliac vein stent thrombus was seen in one patient. One-year follow-up was available in eight patients, with CT imaging demonstrating maintained patency. Median filter implantation time was 12.3 months (mean, 41.9 months; range, 0.8-245.1 months; standard deviation, 63.3 months). Advanced IVCF retrieval techniques were required for 17 procedures. One major AE and minor AE occurred; no patients died in the study period.

CONCLUSIONS

Single-session iliocaval recanalization with IVCF retrieval has high rates of technical and clinical success in patients with IVCF-related chronic iliocaval thrombosis.

Endobronchial Forceps-Assisted Removal of Gianturco Z-Stents from the Right Atrium

Endovascular treatment of malignant intrahepatic inferior vena cava stenosis involves venoplasty and stenting. Intravascular migration is a complication associated with stents. This technical report describes the retrieval of migrated intracardiac Gianturco Z-stents using rigid endobronchial forceps.

Is external compression on the IVC a risk factor for IVC filter abutment? A single center experience of 141 infrarenal celect filter insertions

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Tilt of the IVC filter is the major problem for the filter retrieval rate.

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External compression on the IVC wall can cause filter tilting.

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Identifying external compression factors are necessary before insertion of IVC filter.

Objectives

To investigate risk factors for inferior vena cava (IVC) filter abutment, including external compression on the IVC wall, using venous phase computed tomography (CT).

Methods

One-hundred-forty-one cases of Celect IVC filter insertion between January 2009 and April 2017 were retrospectively reviewed. On pre-procedural CT, IVC diameter and morphological classifications were measured. Filter tilt angle, IVC angle, vertical position, and filter tip abutment to the IVC wall were analyzed on post-procedural CT. IVC compression was examined by pre- and post-procedural CT analysis. Multiple logistic regression analysis was conducted to find factors related to IVC filter abutment.

Results

Of 141 IVC filter insertion cases, 52 were classified in the filter tip abutment group and 89 in the non-abutting group. IVC tilt angle (11.7 ± 5.5° vs. 6.4 ± 5.4°), presence of external compression (14/52, 27% vs. 9/89, 9%), and IVC morphology were different between the groups (p < 0.05). In multiple logistic regression analysis, filter-tilt angle over 9.25° and external compression on the IVC were found to be independent predictors of filter abutment (odds ratios: 4.56, 10.18, respectively).

Conclusion

IVC filter tilt, external compression on IVC wall, and IVC morphology were significantly different between the filter tip abutment and non-abutment groups. External compression and filter tilt over 9.25° were risk factors for filter tip abutment in multiple logistic regression analysis. By identifying these factors, we may be able to reduce filter tilting by preventing the filter from being deployed in a dangerous area.

Endobronchial Forceps-Assisted and Excimer Laser-Assisted Inferior Vena Cava Filter Removal: The Data, Where We Are, and How It Is Done

The recognition of inferior vena cava filter related complications has motivated increased attentiveness in clinical follow-up of patients with inferior vena cava filters and has led to development of multiple approaches for retrieving filters that are challenging or impossible to remove using conventional techniques. Endobronchial forceps and excimer lasers are tools for designed to aid in complex inferior vena cava filter removals. This article discusses endobronchial forceps-assisted and excimer laser-assisted inferior vena cava filter retrievals.

Endovascular Removal of Inferior Vena Cava Filters with Arterial Penetration

PURPOSE

To evaluate the safety and outcomes of endovascular percutaneous removal of inferior vena cava filters (IVCFs) with elements penetrating an artery.

MATERIALS AND METHODS

From an IVCF retrieval database, computerized tomographic scans of patients who underwent IVCF retrieval from 2011 to 2017 were reviewed for IVCF elements penetrating through the caval wall and into an adjacent arterial wall (AW) or penetrating into an adjacent arterial lumen (AL). Forty-two patients were identified, including 20 with elements penetrating into an AW and 22 with elements penetrating into an AL; 30 of these IVCFs were tip embedded.

RESULTS

All of the filters in both groups were removed. Of the arterial-interacting filters, 9 were removed with the use of standard techniques and 33 with the use of endobronchial forceps. Arterial access was obtained before removal in 3 patients (7%) with post-removal arteriography revealing no abnormalities, such as extravasation, pseudoaneurysm, or new fractured components. There was no significant difference between groups in tip embedding, retrieval technique, or fluoroscopy time.

CONCLUSIONS

Endovascular removal of IVCFs with elements that have penetrated into adjacent arterial walls or lumens can be performed safely in the majority of patients.

A modified wire-loop snare technique for the retrieval of inferior vena cava filter with embedded hook

Common obstacles to successful retrieval of retrievable inferior vena cave filter include embedded filter hook and severe tilt of the filter. We described a modified wire-loop snare technique using self-made fishhook-like pigtail catheter and 11-F-long sheath to retrieve a severe tilted filter with embedded hook successfully. The modified wire-loop snare technique is simple and effective requiring only standard equipment and single venous access. This technique may be suitable for some types of retrievable filter with embedded hook.

Inferior vena cava filter use and patient safety: legacy or science?

There has been a dramatic increase in vena cava filter (VCF) use over the past 20 years in the absence of evidence that filters provide a net patient benefit or are required in most cases. This increase is largely attributable to the availability of retrievable filters and expanded indications, particularly as primary prophylaxis in patients thought to be at high risk of pulmonary embolism. Substantial variability in VCF use, unrelated to patient clinical factors, has been shown between hospitals, from region to region, and among various countries. Despite the lack of direct evidence for the benefit of VCFs for any indication, it is appropriate to insert a retrievable VCF in patients with a recent proximal deep vein thrombosis and an absolute contraindication to therapeutic anticoagulation and then to remove the filter once the bleeding risk decreases and the patient has been anticoagulated. Unfortunately, a high proportion of retrievable filters are not removed, even after the reason for their placement has long passed. Retrievable filters are associated with substantial rates of complications if they are not removed, including penetration of the vena caval wall, fracture and embolization of filter fragments, and caval occlusion. Patient safety priorities and medical-legal concerns mandate careful selection of patients for VCF placement and removal shortly after anticoagulation has been initiated.

Complications and Retrieval Data of Vena Cava Filters Based on Specific Infrarenal Location

PURPOSE

Although recommended placement of IVC filters is with their tips positioned at the level of the renal vein inflow, in practice, adherence is limited due to clinical situation or IVC anatomy. We seek to evaluate the indwelling and retrieval complications of IVC filters based on their specific position within the infrarenal IVC.

MATERIALS AND METHODS

Retrospective, single institution study of 333 consecutive infrarenal vena cava filters placed by interventional radiologists in patients with an average age of 62.2 ± 15.7 years was performed between 2013 and 2015. Primary indication was venous thromboembolic disease (n = 320, 96.1%). Filters were classified based on location of the apex below the lowest renal vein inflow on the procedural venogram: less than 1 cm (n = 180, 54.1%), 1-2 cm (n = 96, 28.8%), and greater than 2 cm (n = 57, 17.1%). Denali (n = 171, 51.4%) and Celect (n = 162, 48.6%) filters were evaluated. CT follow-up, indwelling complications, and retrieval data were obtained.

RESULTS

Follow-up CT imaging performed for symptomatic indications occurred for 38.3% of filters placed < 1 cm below the lowest renal vein, 27.1% of filters placed 1-2 cm, and 36.8% placed > 2 cm (p = .16). There was no difference in caval strut penetration, penetration of adjacent viscera, time to penetration, filter migration, or tilt (p = .15, .27, .41, .57, .93). No filter fractures occurred. There was no difference in the incidence of breakthrough PE or complex filter retrieval (p = .83, .59). Only one retrieval failure occurred.

CONCLUSIONS

This study suggests filter apex location within the infrarenal IVC, including placement > 2 cm below the level of the renal vein inflow, is not associated with differences in indwelling or retrieval complications.

LEVEL OF EVIDENCE

Level 3 non-randomized controlled follow-up study.

The Role of Inferior Vena Cava Filters in Pulmonary Embolism

Pulmonary embolism (PE) is a cause of significant morbidity and mortality, with an estimated 600,000 cases of clinically significant PE in the United States annually, and roughly 200,000 deaths per annum directly attributable to PE. By far the most frequent cause of PE is deep vein thrombosis originating in the lower extremities, which travels to the pulmonary vasculature. The mainstay of treatment is anticoagulation, but multiple additional treatments exist for patients in whom anticoagulation is inadequate or contraindicated. The absolute indications for inferior vena cava (IVC) filtration are narrow, but many filters are placed in patients with relative indications. There is growing concern for overuse of IVC filters, with a relatively low rate of retrieval. It is essential for interventional radiologists to understand the appropriate and correct use and retrieval of IVC filters. Familiarity with placement techniques, protocols and techniques for retrieval, current and emerging technologies, and the clinical model for management of venous thromboembolism, will ensure that interventional radiologists remain an integral member of the care team for these often complex patients.

Bidirectional Pull-Back Technique for Retrieval of Strut-Embedded Cylinder-Shaped Filters in Inferior Vena Cava

BACKGROUND IVC filters have been widely accepted as an effective method to prevent pulmonary embolism (PE) in patients with deep venous thrombosis (DVT). However, the placement of IVC filters is associated with significant complications and filter retrieval can be challenging when the filter struts are embedded into the caval wall. MATERIAL AND METHODS Over 26 months, we reviewed the safety and efficacy of the bidirectional pull-back technique for removing strut-embedded IVC filters in 15 consecutive patients. Retrieval procedural data such as in-dwell time, retrieval time, and fluoroscopy time were recorded. Clinical outcomes and procedure-related complications were evaluated by venography or enhanced computed tomography. Histologic tissue was analyzed to reveal the pathologic effects of chronic filter implantation. All patients underwent routine clinical follow-up at a mean time of 12 months (range, 8-14 months). RESULTS Technical success of filter retrieval was achieved in 100%, with mean implantation of 46.6 days (range, 27-66 days). Filter types were as follows: OptEase (n=11) and Aegisy (n=4). The mean retrieval time and fluoroscopy time were 21.43±5.42 min and 7.63±2.67 min, respectively. Immediate postprocedure venography showed no procedure-related complications. Thirteen patients discontinued previously prescribed lifelong anticoagulation. There were no long-term complications during follow-up. CONCLUSIONS The bidirectional pull-back technique is safe and efficient for filter retrieval. This complex technique can be particularly useful in selected patients to remove strut-embedded cylindrical-shaped IVC filters previously considered irretrievable.