Improving inferior vena cava filter retrieval rates with the define, measure, analyze, improve, control methodology

Acute Pulmonary Embolism: Evidence, Innovation, and Horizons

PURPOSE OF REVIEW

Pulmonary embolism (PE) is the third most common cause of cardiovascular morbidity and mortality. The goal of this review is to discuss the most up-to-date literature on epidemiology, diagnosis, risk stratification, and management of acute PE.

RECENT FINDINGS

Despite an increase in annual incidence rate of PE in the United States and development of multiple advanced therapies for treatment of acute PE, PE-related mortality is not consistently decreasing across populations. Although multiple risk stratification schemes have been developed, it is still unclear which advanced therapy should be used for the individual patient and optimal timing. Fortunately, multiple randomized clinical trials are underway to answer these questions. Nevertheless, up to 50% of patients have persistent reduced quality of life 6 months after acute PE, termed post-PE syndrome. Despite advances in therapeutic options for management of acute PE, many questions remain unanswered, including optimal risk stratification and management of acute PE.

A change in strategy for filter choice leads to improved filter retrieval rates

OBJECTIVE

To assess whether a new strategy for the choice of inferior vena cava filter placed would improve filter retrieval rates at our institution.

METHODS

Consecutive patients who underwent retrievable filter placement for temporary embolic protection between January 2021 and January 2023 were considered for study inclusion. Risk factors for nonretrieval of short-term filters were identified in patients receiving filters between January 2021 and January 2022 (prestrategy group). For patients treated between February 2022 and January 2023 (poststrategy group), a long-term filter was recommended for those with these risk factors, and a short-term filter was recommended for those without these risk factors.

RESULTS

The study population included 303 patients (prestrategy group, n = 154; poststrategy group, n = 149). Long-term immobilization (odds ratio [OR] = 38.000; 95% confidence interval [CI]: 6.858-210.564), active cancer (OR = 17.643; 95% CI: 5.462-56.993), and venous thromboembolism detected in the intensive care unit (OR = 28.500; 95% CI: 7.419-109.477) were identified as independent risk factors for nonretrieval of short-term filters. The total retrieval rate was significantly higher in the poststrategy group (87.2%) than in the prestrategy group (72.7%; P = 0.002); the short-term filter retrieval rate was also significantly higher in the poststrategy group (84.5%) than in the prestrategy group (68.5%; P < 0.001).

CONCLUSION

The proposed strategy for filter choice based on risk factors for short-term filter nonretrieval can accurately identify patients who need long-term filter placement while also increasing the retrieval rates for both short-term filters retrieval rates and overall retrieval rates.

Urological complications caused by inferior vena cava filters: a systematic review

INTRODUCTION

Inferior vena cava (IVC) filters act in preventing pulmonary embolisms (PE). Various complications have been reported with their use. However, a credible urological complication rate, filter characteristics, and clinical presentation has yet to be summarized. Thus, we reported these complications in the form of a systematic review.

EVIDENCE ACQUISITION

A search strategy was designed using PubMed, MEDLINE, and EMBASE on February 10th, 2022. The design of this search strategy did not include any language restrictions. The key words (and wildcard terms) used in the search strategy were urolog*, ureter*, bladder, kidney coupled with filter, inferior vena cava, and cava*. Inclusion criteria were: patients older than 18, with previous IVC filter placement, and urologic complication reported. Exclusion criteria were: patients younger than 18, no IVC filter placement, and no urologic complication reported. Other case series and reviews were excluded to avoid patient duplication.

EVIDENCE SYNTHESIS

Thirty-five articles were selected for full-text screening. Thirty-seven patient cases were reviewed, and the median age was 53 (range: 21-92 years old). Abdominal and or flank pain was reported in 16 (43%) patients, hematuria was seen in eight (22%) and two (5%) patients died due to acute renal failure resulting from the urologic complications of the IVC filter. Indications for IVC filter placement were recurrent pulmonary embolism (PE), contraindication to or noncompliance with anticoagulant therapy. The IVC filters were infrarenal in 29 (78.4%) patients, suprarenal in five (13.5%) patients, not reported in two patients, and misplaced into the right ovarian vein in one patient. Three or more imaging modalities were obtained in 19 patients (51%) for planning. IVC filter removal was not performed in 17 (45.9%) patients, endovascular retrieval occurred in nine (24.3%) patients, and open removal was performed in seven (18.9%) patients, and tissue interposition was performed in two (5.4%) patients. One patient did not have the management reported.

CONCLUSIONS

Urological complications caused by IVC filters although rare, are likely underreported, require extensive workup, and pose surgical challenges. Due to their complex management, filter retrieval should be planned for as soon as feasible, and plans should be made as early as during the IVC filter implant. For those that do develop complications, clinical judgement must be exercised in management, and open surgical, endovascular or even conservative management strategies can be viable options and should be discussed in a multidisciplinary setting.

Utilization Practices of Inferior Vena Cava Filters at an Academic Medical Center

INTRODUCTION

 Anticoagulation is the mainstay of management for patients with venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolism (PE). Inferior vena cava (IVC) filters are indicated in select patients who are not candidates for anticoagulation. There is a lack of quality evidence supporting other indications. In addition, long-term benefits and safety profiles of IVC filters have not been established. We investigated the utilization practice of IVC filters in a contemporary series of patients in a tertiary academic medical center.

METHODOLOGY

 A retrospective review of 200 patients who received IVC filters at Virginia Commonwealth University (VCU) Medical Center in the years 2017 and 2018 was conducted. Adult patients 18 years of age or older with or without cancer were included, and patients were selected consecutively until data on 200 patients were collected. Data on patient demographics, an indication of IVC filter placement, filter retrieval rate, and re-thrombosis events over a median follow-up period of nine months were extracted from the electronic medical record and analyzed.

RESULTS

A total of 200 patients (105 male and 95 female) were included with a median age of 61 years (range 17-92 years). Of the 200 patients, 97 (48.5%) had a DVT, 28 (14%) had a PE, 73 (36.5%) had both a PE and DVT, and 2 (1%) had thrombosis at other sites. A total of 130 (65%) patients had an IVC filter placed because of a contraindication to anticoagulation, while 70 (35%) had an IVC filter placed for other nonstandard indications, which included new or worsening VTE despite anticoagulation, recent VTE who must have anticoagulation held during surgery, primary prevention in high-risk patients, and extensive disease burden among other reasons. Seventy-two (36%) patients had active malignancy at the time of filter placement, and 64 (32%) were lost to follow-up. Of the 119 patients who were potentially eligible for filter retrieval, 55 (46%) patients had their IVC filters removed at a median of five months after insertion. Of the 55 patients who had IVC filters removed, 8 (14.5%) patients experienced a re-thrombosis event within a median follow-up of 39 months. Of the 145 patients who still had their filter in place at the time of death or last follow-up, 5 (3.4%) patients experienced a re-thrombosis event within a median follow-up of three months.

CONCLUSIONS

 One-third of the patients in this series had an IVC filter placed without a standard indication, and less than half of them had the IVC filters removed within one year of placement. Additionally, one-third of the patients were lost to follow-up, highlighting the need for improved structured follow-up programs and education among both patients and providers regarding the indications for placement and retrieval to minimize complications.

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.

Reengaging patients with forgotten filters through an institutional multidisciplinary approach

OBJECTIVE

The aim of the present study was to evaluate the outcomes of a hospital-wide multidisciplinary initiative to reengage and manage patients with unretrieved chronic indwelling inferior vena cava (IVC) filters placed at a large tertiary care center, who had been lost to follow-up.

METHODS

We performed a retrospective review of outcomes from a completed multidisciplinary quality improvement project. The quality improvement project identified and contacted (via letter) patients with chronic indwelling IVC filters placed at a single tertiary care center from 2008 to 2016 who were alive and without evidence of filter retrieval in the medical records. A total of 316 eligible patients were mailed a letter regarding their chronic indwelling IVC filter and the updated recommendations regarding IVC filter removal. The letter included institutional contact information, and all the patients who responded were offered a clinic visit to discuss potential filter retrieval. In the retrospective review, we assessed the outcomes of the quality improvement project, including the patient response rate, follow-up clinic visits, new imaging studies generated, retrieval rate, procedural success, and complications. The patient demographics and filter characteristics were collected and evaluated for correlations with the response and retrieval rates.

RESULTS

The patient response rate to the letter was 32% (101 of 316). Of the 101 patients who responded, 72 (71%) were seen in clinic and 59 (82%) underwent new imaging studies. Using standard and advanced techniques, 34 of 36 filters after a median dwell time of 9.4 years (range, 3.3-13.3 years) were successfully retrieved (94% success rate). The patients with a documented IVC filter complication were more likely to respond to the letter (odds ratio, 4.34) and undergo IVC filter retrieval (odds ratio, 6.04). No moderate or severe procedural complications occurred during filter retrieval.

CONCLUSIONS

An institutional, multidisciplinary quality initiative successfully identified and reengaged patients with chronic indwelling IVC filters who had been lost to follow-up. The filter retrieval success rate was high and procedural morbidity low. Institution-wide efforts to identify and retrieve chronic indwelling filters are feasible.

Inferior Vena Cava Filter Retrieval Rates Associated With Passive and Active Surveillance Strategies Adopted by Implanting Physicians

IMPORTANCE

Inferior vena cava filters are commonly implanted and infrequently retrieved. Nonretrieval contributes to significant morbidity, motivating US Food and Drug Administration and multisociety communications emphasizing the need for improved device surveillance. Current guidelines suggest that implanting physicians and referring physicians should be responsible for device follow-up, but it is not known whether shared responsibility contributes to lower retrieval.

OBJECTIVE

To determine if primary responsibility for follow-up care assumed by the implanting physician team is associated with increased device retrieval.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study examined a prospectively collected registry of patients with inferior vena cava filters implanted from June 2011 to September 2019. Medical record review and data analysis was completed in 2021. The study included 699 patients who underwent implantation of retrievable inferior vena cava filters at an academic quaternary care center.

EXPOSURES

Prior to 2016, implanting physicians had a passive surveillance strategy whereby letters highlighting indications for and the need for timely retrieval were mailed to patients and ordering clinicians. Starting in 2016, implanting physicians assumed active responsibility for surveillance, whereby candidacy for device retrieval was assessed periodically via phone calls and retrieval scheduled when appropriate.

MAIN OUTCOMES AND MEASURES

The main outcome was the odds of inferior vena cava filter nonretrieval. Within regression modeling of the association between the surveillance method and nonretrieval, additional covariates of patient demographics, concomitant malignant neoplasm, and presence of thromboembolic disease were included.

RESULTS

Of the 699 patients who received retrievable filter implants, 386 (55.2%) were followed up with passive surveillance, 313 (44.8%) with active surveillance, 346 (49.5%) were female, 100 (14.3%) were Black individuals, and 502 (71.8%) were White individuals. The mean (SD) age at filter implantation was 57.1 (16.0) years. Mean (SD) yearly filter retrieval increased following the adoption of active surveillance, from 190 of 386 (48.7%) to 192 of 313 (61.3%) (P < .001). Fewer filters were deemed permanent in the active group vs passive group (5 of 313 [1.6%] vs 47 of 386 [12.2%]; P < .001). Age at the time of implantation (OR, 1.02; 95% CI, 1.01-1.03), concomitant malignant neoplasm (OR, 2.18; 95% CI, 1.47-3.24), and passive contact method (OR, 1.70; 95% CI, 1.18-2.47) were associated with increased odds of filter nonretrieval.

CONCLUSIONS AND RELEVANCE

The findings of this cohort study suggest that active surveillance by implanting physicians is associated with improved inferior vena cava filter retrieval. These findings support encouraging physicians who implant the filter to take primary responsibility for tracking and retrieval.

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.

The application of inferior vena cava filters in orthopaedics and current research advances

Deep vein thrombosis is a common clinical peripheral vascular disease that occurs frequently in orthopaedic patients and may lead to pulmonary embolism (PE) if the thrombus is dislodged. pulmonary embolism can be prevented by placing an inferior vena cava filter (IVCF) to intercept the dislodged thrombus. Thus, IVCFs play an important role in orthopaedics. However, the occurrence of complications after inferior vena cava filter placement, particularly recurrent thromboembolism, makes it necessary to carefully assess the risk-benefit of filter placement. There is no accepted statement as to whether IVCF should be placed in orthopaedic patients. Based on the problems currently displayed in the use of IVCFs, an ideal IVCF is proposed that does not affect the vessel wall and haemodynamics and intercepts thrombi well. The biodegradable filters that currently exist come close to the description of an ideal filter that can reduce the occurrence of various complications. Currently available biodegradable IVCFs consist of various organic polymeric materials. Biodegradable metals have shown good performance in making biodegradable IVCFs. However, among the available experimental studies on degradable filters, there are no experimental studies on filters made of degradable metals. This article reviews the use of IVCFs in orthopaedics, the current status of filters and the progress of research into biodegradable vena cava filters and suggests possible future developments based on the published literature by an electronic search of PubMed and Medline databases for articles related to IVCFs searchable by October 2022 and a manual search for citations to relevant studies.

New clinic workflow improves compliance for routine PCN exchanges

PURPOSE

To examine the effect of a clinic workflow intervention on follow-up for routine ercutaneous nephrostomy tube (PCN) exchanges.

METHODS

An intervention consisting of automated electronic tracking for all PCN placements and exchanges followed by phone call reminders to schedule a follow-up exchange 60 days post-procedure was introduced on March 19, 2019. All PCN exchanges performed from March 19, 2018 to September 18, 2019 were identified through a local electronic database search to assess the impact of intervention as a quality improvement project. Basic demographic information and procedure details were collected. Routine follow-up at our institution is recommended every 90 days. The exchange rates within 90 days were compared between groups using a Chi-squared test.

RESULTS

A total of 160 PCN placements or exchanges were performed pre-intervention and 69 PCN exchanges were performed post-intervention. Pre-intervention, 75/160 (46.3%) were exchanged within 90 days compared to 47/69 (68.1%) exchanged within 90 days post-intervention. The remainder had delayed follow-up due to loss to follow-up or scheduling delays. Post-intervention, there was a significantly improved rate of compliance for PCN exchanges within the recommended 90 days at our institution (p-value = 0.002).

CONCLUSION

Automated tracking and phone call follow-up at 60 days post-procedure is a simple and effective intervention that can improve compliance for routine PCN exchanges and reduce the number of patients that are lost to follow-up.

Implications for patient follow-up of changes in inferior vena cava filter removal plan practices

AIM

To assess the improvements during patient follow-up after implementing a proactive plan for retrieval of inferior vena cava (IVC) filters.

MATERIALS AND METHODS

A retrospective study was undertaken including all patients who had a temporary IVC filter inserted over a 10-year period. Patient demographics, insertion dates, retrieval dates, retrieval rates, and complications were recorded. Patients were categorised into three groups as follows: group A, no intervention where retrieval was not suggested; group B, passive intervention where retrieval was suggested but no appointment made; and group C, proactive intervention where a retrieval date was booked by the radiologist.

RESULTS

Five hundred and nine patients had a temporary IVC filter inserted at Royal Liverpool University Hospital over the study period. One per cent of patients in group C were lost to follow-up compared to 41% and 29% in groups A and B respectively (p<0.001). The number of patients who had an IVC retrieval attempt also increased to 80% in group C compared to 53% and 64% in groups A and B (p<0.001).

CONCLUSION

Incorporation of a proactive retrieval booking system has significantly reduced the number of patients lost to follow-up to 1%, leading to an increased number of IVC filter retrieval attempts.

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.

A single center 9-year experience in IVC filter retrieval - the importance of an IVC filter registry

Background

To evaluate Inferior vena cava (IVC) filter retrieval practices over a 9-year period at an academic hospital with a prospectively maintained IVC filter registry.

Method

An IVC filter registry was maintained prospectively within our institution. We reviewed cases between August 2011 and June 2020, following filter status, retrieval plans, and eventual retrieval date. The validity of the database was cross referenced with a Picture Archiving and Communication System and patient records.

Results

Three hundred forty-three patients had IVC filters inserted. Three filter types were used, Celect (Cook Medical) in 189, Gunther Tulip (GT) (Cook Medical) in 65, ALN (ALN) in 89. 196 (57%) filters were retrieved, 108 (31.5%) were made permanent, 36 (10.5%) died before retrieval, and 3 (1%) were yet to be retrieved.

Retrieval rates were 92.5% overall (86% for GT, 93% for Celect and 94.5% for ALN). The mean dwell time for successful retrieval was 59 days with the majority of insertions (85%) removed in under 100 days. Failed initial retrieval occurred in 23 patients, 10 (43%) were retrieved at second attempt, 13/23 filters remained in-situ and were deemed permanent.

Conclusion

The removal of IVC filters, when indication for insertion has past, is no longer the sole responsibility of the referring physician but also the responsibility of the Interventionalist. Our retrieval rates of 92.5% of eligible IVC filters highlights the value of maintaining a prospective IVC filter registry.

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.

Comparative outcomes of Inferior Vena Cava filters placed at bedside using digital radiography versus conventional fluoroscopy

Purpose

To retrospectively assess the outcomes of Inferior Vena Cava (IVC) filters placed in critically ill patients in the ICU at bedside using digital radiograph (DR) guidance with previous cross-sectional imaging for planning, compared to IVC filters placed by conventional fluoroscopy (CF).

Method and materials

The cohort consisted of 129 IVC filter placements; 48 placed at bedside and 81 placed conventionally from July 2015 to September 2016. Patient demographics, indication, radiation exposures, access site, procedural duration, dwell time, and complications were identified by the EMR. IVC Filter positioning with measurements of tip to renal vein distance and lateral filter tilt were performed when cavograms or post placement CTs were available for review. Statistical analysis was performed using Stata IC 11.2.

Results

Technical success of the procedure was 100% in both groups. Procedural duration was longer at the bedside lasting 14.5 +/- 10.2 versus 6.7 +/- 6.0 ​min (p<0.0001). The bedside DR group had a median radiation exposure of 25 ​mGy (15–35) and the CF group had mean radiation exposure of 256.94 ​mGy +/- 158.6. There was no significant difference in distance of IVC tip to renal vein (p=0.31), mispositioning (p=0.59), degree of filter tilt (p=0.33), or rate of complications (p=0.65) between the two groups.

Conclusion

IVCF placement at the bedside using DR is comparable to CF with no statistical difference in outcomes based on IVCF positioning, degree of lateral tilt or removal issues. It decreased radiation dose, but with overall increased procedural time.

Current interventional therapies in acute pulmonary embolism

Pulmonary embolism (PE) is the third leading cause of cardiovascular mortality. The management of PE is currently evolving given the development of new technologies and team-based approaches. This document will focus on risk stratification of PEs, review of the current interventional therapies, the role of clinical endpoints to assess the effectiveness of different interventional therapies, and the role for mechanical circulatory support in the complex management of this disease.

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. .

Single center experience of inferior vena cava filter retrieval in trauma patients: contrast-enhanced CT-based retrieval within hospital stay

PURPOSE

To assess the safety and retrieval rate of a predischarge inferior vena cava (IVC) filter retrieval strategy based on contrast computed tomography (CT).

METHODS

IVC filter insertion for trauma patients from 2010 to 2018 were reviewed. An active filter retrieval strategy was established in March 2017. The strategy sought early evaluation of venous thromboembolism (VTE) status and filter retrieval before a patient's discharge. The possibility of early IVC filter retrieval was evaluated by a multidisciplinary team based on pre-filter retrieval VTE-CT findings. Overall VTE-CT findings, retrieval rate, indwelling time, and recurrence of venous thromboembolic events were compared before and after the filter retrieval strategy setup.

RESULTS

177 IVC filters were inserted in trauma patients. All patients underwent pre-filter retrieval VTE-CT. VTE-CT findings were as follows: completely resolved VTE, n = 108 (61%); partially improved, n = 58 (33%); no change, n = 8 (5%); aggravated, n = 3 (2%). The overall retrieval rate was 84% with a mean indwelling time of 32 days. In subgroup analyses, 95 (53%) had filter retrieval with the before strategy (BS) setup and 82 (47%) with the after strategy (AS) setup. The retrieval rate was significantly higher in the AS group [81/82 (99%) vs. 68/95 (72%), (p < 0.001)]. No patients had recurrent VTE during the follow-up period.

CONCLUSIONS

The active strategy of VTE-CT-based filter retrieval during the hospital stay markedly improved the filter retrieval rate from 72% to 99% without evidence of recurrence of VTE. Hazards of low retrieval rate versus CT-related radiation exposure should be studied in the future.

Advanced Management of Intermediate- and High-Risk Pulmonary Embolism: JACC Focus Seminar

Intermediate-risk (submassive) pulmonary embolism (PE) describes normotensive patients with evidence of right ventricular compromise, whereas high-risk (massive) PE comprises those who have experienced hemodynamic decompensation with hypotension, cardiogenic shock, or cardiac arrest. Together, these 2 syndromes represent the most clinically challenging manifestations of the PE spectrum. Prompt therapeutic anticoagulation remains the cornerstone of therapy for both intermediate- and high-risk PE. Patients with intermediate-risk PE who subsequently deteriorate despite anticoagulation and those with high-risk PE require additional advanced therapies, typically focused on pulmonary artery reperfusion. Strategies for reperfusion therapy include systemic fibrinolysis, surgical pulmonary embolectomy, and a growing number of options for catheter-based therapy. Multidisciplinary PE response teams can aid in selection of appropriate management strategies, especially where gaps in evidence exist and guideline recommendations are sparse.

Structured team-oriented program to follow patients after vena cava filter placement: a step forward in improving quality for filter retrieval

To reduce inferior vena cava filter (IVCF) related complications, retrieval is recommended whenever possible. Nevertheless, IVCF retrieval rates remain lower than expected, likely due to insufficient follow-up after placement. We evaluated the value of a structured program designed to follow patients by the interventional radiology team up to 5 months after IVCF placement. We prospectively enrolled 366 consecutive patients (mean age 64 ± 17 years; 201 men and 165 women) who benefited from IVCF between March 2015 and February 2020. The program consisted of advising the patient and clinicians to consider IVCF retrieval as soon as possible (standard workflow) and systematically planning an additional follow-up visit at 5-month. Clinical and technical eligibility, as well as technical success for retrieval (TSR) were evaluated. At 5-months, 38 (10.4%) patients were lost to follow-up, and 47 (12.8%) had died. Among survivors, the overall retrieval rate was 58%. The retrieval rates were 83% and 97% for the clinically eligible and technically eligible patients for retrieval, respectively. The 5-month visit enabled 89 additional retrievals (47.8%) compared to the standard workflow. No significant difference was seen in TSR before and after 5 months (p = 0.95). Improved patient tracking with a dedicated IVCF program results in an effective process to identify suitable patients for retrieval and drastically improves retrieval rates in eligible patients. Involving interventionalists in the process improved IVCF patient management.

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.

Effect of a dedicated inferior vena cava filter retrieval program on retrieval rates and number of patients lost to follow-up

PURPOSE We aimed to assess the efficacy of a dedicated inferior vena cava (IVC) filter retrieval program on filter retrieval rates and number of patients lost to follow-up. METHODS A dedicated IVC filter retrieval program began in July 2016. This consisted of tracking all patients with retrievable filters placed by interventional radiology (IR). At the time of filter placement, patients were scheduled for a retrieval consult in the IR clinic. Any missed appointments were followed up by a physician assistant. The program was overseen by a single IR physician. To assess this program's efficacy, we reviewed the records of all patients who had retrievable IVC filters placed by IR nine months prior to and nine months after program initiation. Demographics and clinical factors were then collected and compared. A P value of < 0.05 was considered statistically significant. RESULTS Prior to the program, 76 patients (31 males, 45 females; mean age, 64.2 years) had retrievable filters placed; 75% were placed due to a contraindication to anticoagulation. From this group, five filters were removed (6.6%), 42 patients were lost to follow-up (55.3%), 22 patients died (29.0%), and seven filters were deemed permanent by a physician after placement (9.2%). All five retrievals were successful and no complications were reported. After program initiation, 106 patients (59 males, 47 females; mean age, 58.8 years) had retrievable filters placed; 75.5% were placed due to a contraindication to anticoagulation. In this group, 30 filters were retrieved (retrieval rate 28.3%), 17 patients were lost to follow-up (16%), 23 patients died (21.7%), 28 filters were deemed permanent by a physician after placement (26.4%), and decisions were still pending in eight patients (7.5%). One patient (3.3%) had a minor complication during filter retrieval. Initiation of a filter retrieval program increased our retrieval rate (6.6% vs. 28.3%; P < 0.001) and reduced the number of patients with filters that were lost to follow-up (55.3% vs. 16%; P < 0.001). CONCLUSION Dedicated filter retrieval program is effective in increasing filter retrieval rates and decreasing the number of patients lost to follow-up.

Changes in inferior vena cava filter placement and retrieval practice patterns from a population health perspective

PURPOSE

Inferior vena cava (IVC) filters are placed to reduce venous thromboembolism (VTE)-related morbidity and mortality, though the evidence supporting this practice is limited. In 2010, the Food and Drug Administration (FDA) released a device safety advisory due to the risk of filter migration, fracture, and thrombosis with long-term use. The purpose of this study was to evaluate trends and predictors for IVCF placement and retrieval over a 10-year time period from a population health perspective.

MATERIALS AND METHODS

De-identified patient information from the State Inpatient Databases (SID) and the States Ambulatory Surgery and Services Databases (SASD) for Florida and California were used to identify all patients who underwent IVC filter placement from 2005 to 2014 and 2005 to 2011, respectively. Hospital practice patterns were assessed as a function of time as well as IVC filter placement and retrieval volume. Temporal trends were evaluated for statistical significance using the Cochran-Armitage test.

RESULTS

A total of 181,260 IVC filters were placed in 178,327 patients over the study period. IVC filter placements peaked in 2010; following the FDA advisory in 2010, however, IVC filter placements monotonically decreased each subsequent year. The proportion of IVCF placement patients with both acute DVT and PE (17.6% vs 11.8%, P < 0.001) at the time of hospitalization increased; likewise, the proportion of IVCF patients with acute DVT or PE with a concomitant acute contraindication to anticoagulation at the time of hospitalization increased as well following 2010 (17.0% vs 11.9%, P < 0.001). From 2005 to 2014, there was a continual increase in both filter retrieval procedures as well overall percentage of filters retrieved. However, estimated retrieval rates remained low, with a retrieval rate of less than 6% in 2014.

CONCLUSION

Following the FDA warning in 2010, there was a significant decrease in IVC filter placements, with filter placements more frequently performed in patients with poorer health. While retrieval rates increased over time, they remained low.

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.

Decreasing Patient Dwell Times for Outpatient Cardiac Nuclear Medicine Studies: The Benefits of SMART Goals, Scope Limitations, and Society Guidelines in Quality Improvement

BACKGROUND

We describe a quality improvement project to improve patient dwell times for outpatient cardiac nuclear medicine exams. Preliminary data indicated that the mean patient dwell time was about 270 minutes. Our specific, measurable, achievable, relevant, and time-bound goal was to reduce patient dwell times for outpatient pharmacologically stressed cardiac nuclear medicine exams by 60 minutes over the course of 2 months.

METHODS

An interdisciplinary team was formed which used staff interviews and workflow observation to create a cause and effect diagram as well as a process map. Review of the national guidelines for cardiac nuclear medicine exams identified rest and stress intervals as intervention targets. A new protocol was designed and implemented.

RESULTS

The mean patient dwell time was improved from 270 to 184 minutes.

CONCLUSIONS

Overall, we found that a clear specific, measurable, achievable, relevant, and time-bound goal, limited scope, and national guideline review allowed for a successful quality improvement project.

The role of an IVC filter retrieval clinic-A single center retrospective analysis

Background:

Inferior vena cava (IVC) filter placement still plays an essential role in preventing pulmonary embolism (PE) in patients with contraindications to anticoagulant therapy. However, IVC filter placement does have long-term risks which may be mitigated by retrieving them as soon as clinically acceptable. A dedicated IVC filter clinic provides a potential means of assuring adequate follow-up and retrieval.

Aim:

To assess the efficacy of our Inferior vena cava (IVC) filter retrieval clinic at improving the rate of patient follow-up, effective filter management, and retrieval rates.

Materials and Methods:

During the period of August 2017 through July 2018, 70 IVC filters were placed at our institution, and these patients were automatically enrolled into our IVC filter retrieval clinic for quarterly follow-up. We retrospectively reviewed data including appropriateness for removal at 3 months, overall retrieval rates, removal technique(s) employed, and technical success.

Results:

62.9% of the potentially retrievable filters were removed during the study period. The technical success of extraction, using a combination of standard and advanced techniques, was 91.7%. Overall, 15% of the patients were lost to follow-up.

Conclusion:

Our findings add to the growing body of literature to support the need for a robust IVC filter retrieval clinic to ensure adequate follow-up and timely retrieval of IVC filters.

Innovations in the Plastic Surgery Care Pathway: Using Telemedicine for Clinical Efficiency and Patient Satisfaction

BACKGROUND

Telemedicine delivers clinical information and permits discussion between providers and patients at a distance. Postoperative visits may be a burden to patients-many of whom travel long distances and miss work opportunities. By implementing a telehealth opportunity, the authors sought to develop a process that optimizes efficiency and provides optimal patient satisfaction.

METHODS

Using quality improvement methods that have been highly effective in the business sector, we developed a testable workflow for patients in the postoperative telehealth setting. Seventy-two patients were enrolled and surveyed. A preoperative survey sought to determine travel distance, comfort with technology, access to the Internet and video-enabled devices, and the patient's interest in telehealth. A postoperative survey focused on patient satisfaction with the experience.

RESULTS

Using the Lean Six Sigma methodology, the authors developed a telehealth workflow to optimize clinical efficiency. Preoperative surveys revealed that the majority (73 percent) of patients preferred in-person follow-up visits in the clinic. However, the postoperative survey distributed after the telehealth encounter found that nearly 100 percent of patients were satisfied with the telehealth experience. Ninety-six percent of patients said that their questions were answered, and 97 percent of patients stated that they would use telehealth again in the future.

CONCLUSIONS

Telehealth encounters enable real-time clinical decision-making by providing patients and visiting nurses access to providers and decreasing patient transportation needs and wait times. Although initially hesitant to opt for a telehealth encounter in lieu of a traditional visit, the great majority of patients voiced satisfaction with the telehealth experience.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

The Clinical Rationale for the Sentry Bioconvertible Inferior Vena Cava Filter for the Prevention of Pulmonary Embolism

The Sentry inferior vena cava (IVC) filter is designed to provide temporary protection against pulmonary embolism (PE) during transient high-risk periods and then to bioconvert after 60 days after implantation. At the time of bioconversion, the device's nitinol arms retract from the filtering position into the caval wall. Subsequently, the stable stent-like nitinol frame is endothelialized. The Sentry bioconvertible IVC filter has been evaluated in a multicenter investigational-device-exemption pivotal trial (NCT01975090) of 129 patients with documented deep vein thrombosis (DVT) or PE, or at temporary risk of developing DVT or PE, and with contraindications to anticoagulation. Successful filter conversion was observed in 95.7% of patients at 6 months (110/115) and 96.4% at 12 months (106/110). Through 12 months, there were no cases of symptomatic PE. The rationale for development of the Sentry bioconvertible device includes the following considerations: (1) the period of highest risk of PE for the vast majority of patients occurs within the first 60 days after an index event, with most of the PEs occurring in the first 30 days; (2) the design of retrievable IVC filters to support their removal after a transitory high-PE-risk period has, in practice, been associated with insecure filter dynamics and time-dependent complications including tilting, fracture, embolization, migration, and IVC perforation; (3) most retrievable IVC filters are placed for temporary protection, but for a variety of reasons they are not removed in any more than half of implanted patients, and when removal is attempted, the procedure is not always successful even with advanced techniques; and (4) analysis of Medicare hospital data suggests that payment for the retrieval procedure does not routinely compensate for expense. The Sentry device is not intended for removal after bioconversion. In initial clinical use, complications have been limited. Long-term results for the Sentry bioconvertible IVC filter are anticipated soon.

Improving the practice of inferior vena cava filter retrieval: a quality improvement intervention and audit outcomes

OBJECTIVE

To review inferior vena cava (IVC) filter retrieval practice at our institution, the Royal London Hospital, and measure changes following a quality improvement intervention. IVC filters are a preventive treatment for pulmonary embolism when anticoagulation is ineffective/contraindicated. Unless permanent filtration is required, all filters should undergo attempted retrieval within manufacturer's recommendations with a success rate of ≥80 %.

METHODS

Retrospective audit of filters inserted between 2011 and 2014, followed by a quality improvement intervention and a second audit between 2015 and 2017. Clinical-radiological data were analysed using the Picture Archiving and Communication System and electronic patient records.

RESULTS

During the first audit, filter retrieval was attempted in 92% of cases, of which 82% underwent the procedure within manufacturer's recommendations and 86% were successful. During the second audit, an improvement across indicators was seen. Retrieval increased by 3% and was attempted in 95% of cases (92% of which were within manufacturer's guidelines). Rate of retrievals within manufacturer's guidelines increased by 10%. Filter retrieval success rate increased by 11% - to 97%.

CONCLUSIONS

IVC filter retrieval practice at a single institution can be improved by implementing a simple audit intervention.

ADVANCES IN KNOWLEDGE

Filter retrieval practice has clinical and medicolegal implications. A simple quality intervention can substantially improve overall practice.

Randomized Controlled Study of an Absorbable Vena Cava Filter in a Porcine Model

PURPOSE

To compare the safety and efficacy of an absorbable inferior vena cava (IVC) filter and a benchmark IVC filter in a porcine model.

MATERIALS AND METHODS

A randomized controlled Good Laboratory Practice study was performed in Domestic Yorkshire cross swine. Sixteen swine were implanted with an absorbable IVC filter (test device; Adient Medical, Pearland, Texas); 8 were implanted with a benchmark metal IVC filter (control device; Cook Medical, Bloomington, Indiana). All animals underwent rotational digital subtraction pulmonary angiography and cavography (anteroposterior and lateral) before filter deployment and 5 and 32 weeks after deployment. Terminal procedures and necropsy were performed at 32 weeks. The IVC, heart, lungs, liver, and kidneys were harvested at necropsy. The reported randomized controlled GLP animal study was conducted at Synchrony Labs, Durham, North Carolina.

RESULTS

One animal died early in the test cohort of a recurring hemorrhage at the femoral access site resulting from a filter placement complication. All other animals remained clinically healthy throughout the study. No pulmonary embolism was detected at the 5- and 32-week follow-up visits. The absorbable filter subjects experienced less caval wall perforation (0% vs 100%) and thrombosis (0% vs 75%). The control device routinely perforated the IVC and occasionally produced collateral trauma to adjacent tissues (psoas muscle and aorta). The veins implanted with the absorbable filter were macroscopically indistinguishable from normal adjacent veins at 32 weeks except for the presence of radiopaque markers. Nontarget tissues showed no device-related changes.

CONCLUSIONS

Implantation of the absorbable IVC filter in swine proved safe with no pulmonary emboli detected. There was complete to near-complete resorption of the filter polymer by 32 weeks with restoration of the normal appearance and structure of the IVC.

Arteriovenous Fistula-A Rare Complication of IVC Filter Retrieval

Inferior vena cava (IVC) filters are important devices for patients who are at high risk for developing thrombi and pulmonary embolism but have conditions that preclude the use of pharmacologic anticoagulants. IVC filter retrieval has become an important quality initiative backed by Food and Drug Administration guidelines for prompt removal after the filter is no longer indicated. Filter retrieval is a common procedure that usually has very few complications. However, when the filter is tilted or embedded in the caval wall, advanced techniques of retrieval may be necessary. These techniques have a higher rate of success but also a higher risk of complications such as injury to the IVC. Here, we describe a case of IVC filter retrieval resulting in formation of an arteriovenous fistula between the right renal artery and IVC and subsequent successful repair of this fistula using a vascular plug.

Inferior Vena Cava Filters: Why, Who, and for How Long?

Vena cava filters are implantable devices that are placed to trap thrombus originating in the lower extremities and prevent it from migrating to the lungs. In general, inferior vena cava (IVC) filters are indicated for patients who cannot receive anticoagulation. Other indications for IVC filtration are less clear, and guidelines vary. All patients who have a retrievable IVC filter should be followed, and the removal of the IVC filter should be considered once its indication is lost.

Usefulness of a Computerized Reminder System to Improve Inferior Vena Cava Filter Retrieval and Complications

Inferior vena cava filters (IVCF) are associated with complications which may be due to delayed retrieval. Initiation of an automated reminder system may improve retrieval rates and reduce complications. A computerized reminder system, which provides interactive email reminders after implantation while collecting IVCF use data, was implemented. IVCF retrieval was compared before ("reminder not provided" group) and after ("reminder provided" group) implementation. Data regarding implantation, retrieval, and complications were collected. The primary efficacy outcome was retrieval rate, and the primary safety outcome was indwelling complication rate. Secondary outcomes were time to retrieval and a composite adverse outcome defined as IVCF thrombosis, deep venous thrombosis (DVT), pulmonary embolism, and death. A total of 1,070 IVCF insertions were included, 715 in the "reminder not provided" group and 355 in the "reminder provided" group. Patient age (61 vs 64 years, p = 0.95) and gender (42% vs 40% female, p = 0.55) were similar in the "reminder not provided" and "reminder provided" groups, respectively. In the "reminder provided" group, the retrieval rate was higher (148/297 [49.8%] vs 223/715 [31.2%], p = 0.0001), the indwelling complication rate was lower (30/319 [9.4%] vs 115/715 [16.1%], p = 0.005), and the time to retrieval was shorter (112 days vs 146 days, p = 0.02). The composite adverse outcome occurred less frequently in the "reminder provided" group: (85/355 [23.9%] vs 297/715 [41.5%], p = 0.0001). The system was associated with increased odds of IVCF retrieval (odds ratio 2.56; 95% confidence interval: 1.82 to 3.59; p <0.0001) and reduced odds of the composite adverse outcome (odds ratio 0.72; 95% confidence interval: 0.60 to 0.80; p <0.0001). In conclusion, implementing a computerized email reminder system was associated with higher IVCF retrieval rates, fewer indwelling complications, and shorter dwell times.

Factors Affecting Inferior Vena Cava Filter Retrieval: A Review

Objective:

Over the last 2 decades, there has been an exponential rise in placement of retrievable inferior vena cava (IVC) filters, while the retrieval rate has remained steadily low. Approaches to increasing filter retrieval rates have been extensively studied.

Conclusion:

This review presents an up-to-date review of reported data-driven variables that affect retrieval rates of IVC filters, with a focus on clinical, technical, and process factors.

Persistently low inferior vena cava filter retrieval rates in a population-based cohort

BACKGROUND

Practice patterns associated with inferior vena cava (IVC) filter placement have seen considerable variation in the last decade. We used a statewide administrative database to examine trends in IVC filter placement and retrieval in the general population.

METHODS

We reviewed Florida state inpatient and ambulatory surgery databases from 2004 to 2014. International Classification of Diseases, Ninth Revision diagnosis and procedure codes and Current Procedural Terminology codes were searched for patients undergoing inpatient or outpatient IVC filter placement, and each patient was longitudinally tracked to the time of inpatient or outpatient filter retrieval. For inpatient filter placements, associated diagnoses were reviewed to identify indications for placement. Univariate and multivariate logistic regression models were constructed to identify factors associated with improved retrieval rates.

RESULTS

During the 11-year period, 131,791 IVC filter placements were identified, with a 50% increase from 2004 to 2010 and a 24% decline from 2010 to 2014. Median age at filter placement was 71 years (interquartile range, 57-81 years). Mean follow-up after filter placement was 17.3 ± 25.5 months. Only 8637 filters (6.6%) were retrieved. The annual retrieval rate trended upward, from 3.4% in 2004 to 8.5% in 2013 (P < .001). Median filter dwell time was 96.5 days (interquartile range, 44-178 days). Diagnoses associated with filter placement included venous thromboembolism (75.9%), trauma (35.0%), hemorrhage (29.9%), malignant disease (29.4%), and stroke (5.1%). Retrieval rates were highest in younger patients (34.0% in patients younger than 20 years) and lowest in Medicare patients (2.5%). In a multivariate logistic regression model, Medicare was associated with decreased retrieval rates (odds ratio, 0.33; 95% confidence interval, 0.31-0.35; P < .001) after adjusting for age and associated diagnoses. Weaker risk factors included increased age, white race, and diagnoses of deep venous thrombosis, pulmonary embolism, and malignant disease. A trauma diagnosis was associated with improved retrieval. To further investigate the Medicare effect, a propensity score-matched model was created to better account for confounding effects. In this model, Medicare persisted as a risk factor for decreased filter retrieval (odds ratio, 0.43; 95% confidence interval, 0.40-0.46; P < .001).

CONCLUSIONS

IVC filter placements, after a substantial increase between 2004 and 2010, have been declining since 2010. Retrieval rates in the general population are steadily improving but continue to lag behind those described in center-specific literature. Increased age and Medicare as the primary payer are the strongest risk factors for lack of filter retrieval. Widespread improvements on a national scale are needed to improve the appropriateness of filter placements and to enhance filter retrieval rates.

Long-term complications of inferior vena cava filters

Anticoagulation is the cornerstone for the treatment of deep venous thrombosis and pulmonary embolism. On occasion, this is not possible because of bleeding complications or, rarely, breakthrough pulmonary embolism associated with this treatment method. The development of vena cava interruption in the 1970s was a critical advance in the treatment of these patients. Placement of inferior vena cava (IVC) filters has been steadily increasing since their introduction. Nonetheless, the incidence of complications associated with placement of these devices is largely unknown. Most of the evidence regarding IVC filter complications relies on case reports, with scarce data coming from larger randomized controlled trials. We aimed to present a summary addressing long-term complications of IVC filters as published in recent articles addressing problems such as IVC thrombosis and IVC filter migration, perforation, fracture, embolization, and tilting. We performed a PubMed search and Google Scholar search using different combinations of "long term," "complications," "IVC filter," and "vena cava filter." We reviewed the available English publications and reported the findings in this summary.

Non-retrieval of inferior vena cava filters as a patient safety concern: evaluation of a new process improvement project to increase retrieval rates in a vascular and interventional radiology clinic

Background

Retrieval of inferior vena cava filters (IVCFs) is important to decrease the long-term risk of complications associated with indwelling devices. Our hospital experienced low retrieval rates and implemented a low-cost intervention and evaluation for quality improvement. The working hypothesis was that a simple, mailed letter intervention could increase retrieval rates by increasing patient and primary care provider knowledge of the need for retrieval.

Methods

For all prospective patients who received a retrievable IVCF during the intervention period from January 1, 2014 to February 29, 2016, patients and their primary care providers were mailed letters encouraging contact with the clinic for evaluation of eligibility for retrieval. The main outcome was retrieval of the IVCF if clinically indicated with a secondary outcome of time-to-retrieval. A pre-intervention control group from October 1, 2011 to December 31, 2013 was used to evaluate the impact of the intervention. Competing risks, time-to-event analysis was used to compare the pre- and post-intervention period retrieval rates correcting for patients who died during follow-up.

Results

Between the pre- and post-intervention periods, crude retrieval rates increased from 4.4% to 8.1% with a 12-fold change at comparable time points. The time-to-retrieval in the pre-intervention period was a mean (SD) of 503 (207) days with a median (IQR) of 505 (301–742). In the post-intervention period, time-to-retrieval was a mean (SD) of 119 (83) days and with median (IQR) of 128 (38–164) days.

Conclusions

This low-cost intervention significantly increased retrieval rates in a single clinic. However, retrieval rates remain low and can be further improved. Ongoing interventions, including improved patient follow-up and physician education, are being implemented to further improve retrieval and use of inferior vena cava filters. Implanting clinics should implement quality improvement initiatives to improve patient care and follow-up with IVCFs to ensure retrievals occur once clinically relevant in order to minimize long-term complications.

Patient and hospital characteristics predictive of inferior vena cava filter usage in venous thromboembolism patients: A study from the 2013 to 2014 Nationwide Readmissions Database

To examine the association between patient and hospital characteristics and inferior vena cava filter (IVCF) utilization in patients with venous thromboembolism (VTE).The 2013 to 2014 Nationwide Readmissions Database was used to define a cohort of patients with VTE aged ≥18 after a primary VTE diagnosis. Comorbidities of interest were classified via diagnosis codes and IVCF placement was identified via procedure code. Chi square analysis tested differences between patient and hospital-level characteristics and whether or not IVCFs were placed. A hierarchical logistic regression model estimated the relationship between patient-level factors (demographics, socioeconomic status, comorbidities), hospital-level factors (bed size, teaching status, urbanity) and whether or not IVCFs were placed. Additional models were specified to examine goodness of fit across methodological alternatives.There were 212,395 VTE hospitalizations, with 12.18% (n = 25,877) receiving IVCF placement. There were significant differences between those who did and did not receive IVCF placement; notably, those receiving IVCFs were older (P < .001), had Medicare insurance more than private (P < .001), longer lengths of stay (P < .001), and were in privately owned hospitals (P < .001). IVCF placement remained significantly associated with patient and hospital-level characteristics following multivariate adjustment via hierarchical logistic regression; notably, age >80 (adjusted Odds Ratio [aOR]: 2.53, 95% confidence interval [CI]: 2.25-2.85), ≥13 comorbid conditions (aOR: 3.85, 95% CI: 3.25-4.27), and privately owned hospitals (aOR: 1.21, 95% CI: 1.08-1.36). Optimal goodness-of-fit was achieved with a combination of random effects and patient-level fixed effects.These findings provide evidence that combinations of patient and hospital-level factors are related to whether patients with VTE receive IVCFs.

Utility of Retrievable Inferior Vena Cava Filters: A Systematic Literature Review and Analysis of the Reasons for Nonretrieval of Filters with Temporary Indications

OBJECTIVE

To investigate the use of retrievable inferior vena cava (IVC) filters in the current practice and analyze the causes of filter left in situ despite initial plans for retrieval.

METHODS

A systematic search of all English-language studies of retrievable IVC filters was conducted, including clinical trials and observational studies published between January 1984 and March 2016.

RESULTS

A total of 103 studies were identified, including 10 filter models in 20,319 patients. Placement indications were reported for 11,128 (54.8%) patients, including therapeutic (n = 6270; 56.3%) and prophylactic (n = 4858; 43.7%) indications. A total of 13,224 (65.1%) filters were left as permanent devices; 7095 (34.9%) filters were removed. The reasons for filter nonretrieval among the 5308 (40.1%) reported cases were primary permanent indication (21.2%; 1127/5308), death (19.4%; 1031/5308), ongoing pulmonary embolism (PE) protection (19.0%; 1011/5308), failed retrieval (13.7%; 725/5308), loss to follow-up (13.0%; 689/5308), discontinued care (4.4%; 235/5308), physician oversight (4.0%; 213/5308), patient morbidity (2.8%; 149/5308), and patient refusal (2.4%; 128/5308). A total of 7820 patients presented for filter retrieval, and 7095 filters (90.7%) were successfully removed, with a mean indwelling time of 106.6 ± 47.3 days. Breakthrough PE was reported in 2.1% (191/9169) of patients. Filter tilt, recurrent deep vein thrombosis, penetration, IVC thrombosis, migration, and fracture occurred in 7.7% (798/10,348), 7.1% (362/5092), 5.4% (379/7001), 3.9% (345/8788), 1.4% (160/11,679), and 0.5% (50/9509) of patients, respectively.

CONCLUSIONS

Approximately two-thirds of retrievable filters were not retrieved even though more than 85% of the filters were initially intended for temporary use. The major reasons for filter left in situ despite initial plans for retrieval were death, need for ongoing PE protection, failed retrieval, loss to follow-up, discontinued care, and physician oversight.

Factors associated with reduced radiation exposure, cost, and technical difficulty of inferior vena cava filter placement and retrieval

We sought to delineate factors of inferior vena cava filter placement associated with increased radiation and cost and difficult subsequent retrieval. In total, 299 procedures from August 2013 to December 2014, 252 in a fluoroscopy suite (FS) and 47 in the operating room (OR), were reviewed for radiation exposure, fluoroscopy time, filter type, and angulation. The number of retrieval devices and fluoroscopy time needed for retrieval were assessed. Multiple linear regression assessed the impact of filter type, procedure location, and patient and procedural variables on radiation dose, fluoroscopy time, and filter angulation. Logistic regression assessed the impact of filter angulation, type, and filtration duration on retrieval difficulty. Access site and filter type had no impact on radiation exposure. However, placement in the OR, compared to the FS, entailed more radiation (156.3 vs 71.4 mGy; P = 0.001), fluoroscopy time (6.1 vs 2.8 min; P < 0.001), and filter angulation (4.8° vs 2.6°; P < 0.001). Angulation was primarily dependent on filter type (P = 0.02), with VenaTech and Denali filters associated with decreased angulation (2.2°, 2.4°) and Option filters associated with greater angulation (4.2°). Filter angulation, but not filter type or filtration duration, predicted cases requiring >1 retrieval device (P < 0.001) and >30 min fluoroscopy time (P = 0.02). Cost savings for placement in the FS vs OR were estimated at $444.50 per case. In conclusion, increased radiation and cost were associated with placement in the OR. Filter angulation independently predicted difficult filter retrieval; angulation was determined by filter type. Performing filter placement in the FS using specific filters may reduce radiation and cost while enabling future retrieval.

Prophylactic Inferior Vena Cava Filter Utilization and Risk Factors for Nonretrieval

PURPOSE

Inferior vena cava filters (IVCFs) are often placed for prophylactic indications. We sought to better define the range of practice indications for placement of prophylactic IVCFs, as well as the specific retrieval rate and risk factors for nonretrieval.

METHODS

A retrospective, single-institution review of patients undergoing IVCF placement over a 2-year period was performed. Patients undergoing prophylactic IVCF placement were selected from a prospectively collected database. Risk factors for nonretrieval were identified using a multivariate logistic regression model.

RESULTS

Of 615 IVCFs placed, 256 were retrievable filters placed for prophylactic indications and comprised the study cohort. The most common indications were a history of venous thromboembolic disease (43.7%), malignancy (35.1%), bleeding risk precluding anticoagulation (33.9%), and trauma (22.6%). One hundred sixty-three (63.6%) were placed preoperatively. Placement was performed in 70.3% by interventional radiology, 21.4% by vascular surgery, and 8.2% by cardiology. The most common requesting services were orthopedics (67%), general surgery (11%), neurosurgery (9%), and bariatric surgery (7%). Of all, 67.6% were placed in the inpatient setting and 32.4% in outpatients. Seventy-one (27.7%) of the 256 prophylactic filters were retrieved, with a mean indwelling time of 92 ± 74 days. Inpatients were significantly less likely to have their IVCF removed (32.4% vs 57.8%; P < .001), as were preoperative patients.

CONCLUSIONS

This study helps define current practice trends for the placement of prophylactic IVCFs. Importantly, the specific retrieval rate for prophylactic filters is low. This suggests that prophylactic IVCF usage is suboptimal and efforts should be taken to increase retrieval, especially among inpatients and perioperative patients.