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.

Inferior vena cava filter use at a large community hospital: a retrospective cohort study

Inferior vena cava (IVC) filters are considered when patients with venous thromboembolism (VTE) develop a contraindication to anticoagulation. Use of IVC filters is increasing, despite associated complications and lack of data on efficacy in reducing VTE-related mortality. We characterized the pattern of IVC filter use at a large community hospital between 2018 and 2022. Specifically, we assessed the indications for IVC filter insertion, filter removal rates, and filter-associated complications. Indications for IVC filters were compared to those outlined by current clinical practice guidelines. We reviewed 120 consecutive filter placement events. The most common indications included recent VTE and active bleeding (40.0%) or need for anticoagulation interruption for surgery (25.8%). Approximately one-third (30.0%) of IVC filters were inserted for indications either not supported or addressed by guidelines. Half (50.0%) of patients had successful removal of their IVC filter. At least 13 patients (10.8%) experienced a filter-related complication. In a large community-based practice, nearly one-third of IVC filters were inserted for indications not universally supported by current practice guidelines. Moreover, most IVC filters were not removed, raising the risk of filter-associated complications, and supporting the need for development of comprehensive guidelines addressing use of IVC filters, and post-insertion monitoring practices.

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.

Influence of Exercise on Inferior Vena Cava Wall Interaction with Inferior Vena Cava Filters: Results of a Pilot In Vivo Porcine Study

Purpose The aim of this study was to assess the effect of mild exercise on inferior vena cava (IVC) filter interaction with imaging and pathological features with the neighboring vessel wall utilizing a porcine model.

Methods After Institutional Animal Care and Use Committee (IACUC) approval, retrievable Option Elite IVC filters were implanted in six Yorkshire pigs utilizing the right common femoral vein approach under general anesthesia. Group A (n = 4) pigs remained sedentary for 4 weeks. Group B (n = 2) pigs were exercised using a harness and treadmill for 10 minutes/day for 4 days/week. At approximately 4 weeks, IVC venograms were performed and the pigs were sacrificed. After laparotomy, the IVC was ligated above and below the filter, excised and fixed in formalin. Gross and histological examination of the IVC was performed. Gross images of each sample were captured before removal of the filters. One longitudinal, one tangential, and five transverse representative sections were processed for paraffin sectioning and hematoxylin and eosin slides were prepared. A pathologist examined all tissues to assess differences between normal vein, group A and group B pigs. The pathologist provided an overall assessment and representative images.

Results All IVC filter implantations were technically successful without adverse effects. There was no incidence of caval thrombosis, filter strut fracture, or filter migration in either group. On gross pathological examination, IVC of the pigs in group B demonstrated more perivascular and mural fibrosis than those pigs in group A. Histopathological findings correlated with gross findings.

Conclusions In this pilot study, there were no incidence of IVC filter strut fracture, penetration or IVC occlusion in sedentary or exercised pigs. However, there tended to be more perivascular and mural fibrosis on pathological examination of inferior vena cavas from exercised pigs. Further larger scale studies may employ the porcine model to further understand the role exercise may play on IVC filter and caval wall interaction.

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.

Efficacy and safety of rivaroxaban in patients with inferior vena cava filter placement without anticoagulation contraindications (EPICT): a prospective randomised controlled trial study protocol

INTRODUCTION

Inferior vena cava (IVC) filters are commonly used in patients with venous thromboembolism to prevent fatal pulmonary embolism, but the thrombosis risk increases after filter placement. Warfarin is a widely anticoagulant, but long-term monitoring and dose adjustments are required. Anticoagulation with rivaroxaban is more straightforward as it dose not require laboratory monitoring. This study compares the efficacy and safety of rivaroxaban and warfarin as an in anticoagulation therapy for patients with IVC filter placement.

METHODS AND ANALYSIS

This is a multicentre, randomised controlled trial. In total, 200 patients with deep vein thrombosis (DVT) with IVC filter implantation from 10 hospitals will be recruited. The patients will be randomised to the experimental group (rivaroxaban) or the control group (nadroparin overlapped with warfarin). The primary outcomes include death of any cause, pulmonary embolism (PE)-related death, bleeding and recurrent PE/DVT. The secondary outcomes include the percentage of other vascular events, IVC filter retrieval failure and net clinical benefits. This study aims to provide reliable, verification for the efficacy and safety of rivaroxaban antithrombotic therapy after IVC filter placement.

ETHICS AND DISSEMINATION

The study was approved by the Human Research Ethics Committee of the Second Affiliated Hospital of Zhejiang University School of Medicine (approval number: (2019) 295). The results will be disseminated through presentations at scientific conferences and publications in peer-reviewed journals TRIAL REGISTRATION NUMBER: NCT04066764.

Cardiac Tamponade Secondary to IVC Filter Retrieval

Cardiac tamponade is a rare but potentially fatal complication of inferior vena cava filter retrieval. We discuss such a case to facilitate prompt recognition and prevention of this complication by medical providers. (Level of Difficulty: Beginner.)

A review of anticoagulation in patients with central nervous system malignancy: between a rock and a hard place

The incidence and prevalence of patients who develop primary and secondary metastatic central nervous system cancer (CNS) is increasing. This is a consequence of advancements in the sensitivity and availability of diagnostic imaging, and improved therapeutic options, leading to increased detection of CNS malignancies and improved survival. These patients are at very high risk of thrombosis as well as haemorrhage, and the optimum management of anticoagulation can be challenging for treating clinicians, particularly as robust prospective evidence is sparse. In this focused review, we discuss (1) risk factors for thrombosis and bleeding in these patients, (2) management of acute venous thromboembolism (VTE) including evidence for direct oral anticoagulants, and how to approach patients with contraindications to anticoagulation, (3) ambulatory VTE prophylaxis, (4) VTE prophylaxis in patients who have undergone craniotomy for cancer, and (5) management of anticoagulation-related intracranial haemorrhage. Based on review of the available literature and author opinion, we propose practical management algorithms to aid clinicians faced with treating CNS cancer patients with thrombosis or CNS haemorrhage.

[Total laparoscopic retrieval of a cava filter: case series]

Despite the fact that prevention and treatment of venous thromboembolic complications are based on anticoagulant therapy in cases where there are contraindications, complications, as well as in case of inefficiency of the carried out anticoagulant therapy, installation of a cava filter is indicated. The necessity of subsequent retrieval of this device from the inferior vena cava is associated with a potential risk of the development of complications. Analysed herein is a case series concerning management of 4 patients undergoing treatment from February 2015 to March 2017. Attempts of endovascular retrieval of the cava filter turned out unsuccessful. The patients were therefore subjected to total laparoscopic retrieval of the cava filter. The time required for phlebotomy, retrieval of the filter, and suturing of the phlebectomy zone ranged from 32 to 45 min. The maximal blood loss amounted to 300 ml, not requiring transfusion of blood preparations. Neither was required conversion to laparotomy in any case. No significant systemic or wound complications in the postoperative period were observed. A conclusion drawn is that in case of failed attempts at endovascular retrieval, given that a surgical team has broad experience in performing laparoscopic and angiosurgical operations, total laparoscopic retrieval of a cava filter may be considered a relatively safe minimally invasive method of managing the patient cohort concerned.