A review of inferior vena cava filters

Radiographic Characterization of Inferior Vena Cava and Its Reaction Following Filter Placement: A Single-Center Retrospective Study

OBJECTIVE

To classify the radiographic characterization of the inferior vena cava (IVC) diameter, as well as to quantitatively describe the dimensional alternations in response to variations in filter placement, using cross-sectional computer tomographic venography (CTV) imaging.

METHODS

A single-center retrospective study was conducted on eligible patients who underwent CTV of IVC both before and after the placement of spindle-shaped filters, from September 2018 to June 2023. Baseline data, IVC diameter and orientation pre- and post-filter placement, IVC enlargement rate, and related complications were analyzed.

RESULTS

A total of 70 eligible patients were included, 52 (74.3%) with type 1 IVC, 11 (15.7%) with type 2, 4 (5.7%) with type 3, 3 (4.3%) with type 4, and none with type 5. An accompanying morphological alteration turned IVC into a quasi-round shape with Lin CCC of 0.870, and orientation was significantly altered after filter placement. In patients with type 1, 3, and 4 IVCs, the mean diameter of the IVC increased almost 1.5-fold in the minor axis (95% confidence intervals [CIs]=-7.77 to -5.83, p<0.001), while only a slight expansion of the major axis to its initial size (p>0.05). Greater IVC enlargement rate was seen in the diameter of the minor axis than in the major axis (95% CI=40.31 to 65.12, p<0.001). Notably, regional clots around the filter were found in 22 (31.4%) patients. Among them, 14 (20.0%) were located on the anterior or posterior walls of caval minor axis, 5 (7.1%) in the lateral walls, and 3 (4.3%) in the central part of the IVC filter. Patients exhibited a higher incidence of clots on anterior and posterior walls compared to lateral wall (20.0% vs 7.1%, p=0.014).

CONCLUSION

The morphology of IVC shifted toward an approximated as circles after filter placement, with greater diameter changes seen in the minor axis compared to the major axis, where filter-related thrombosis most occurs.

CLINICAL IMPACT

The findings of this study offer insights into the biomechanical interaction between the inferior vena cava (IVC) and spindle-shaped filters, highlighting the anisotropic dimensional changes triggered by filter placement. The pronounced expansion along the minor axis, where filter-related thrombosis was more frequently observed, underscores a previously underrecognized risk factor for post-implantation complications. These results indicate that perioperative optimization of IVC dimensions and vigilant post-placement monitoring are crucial for improving patient outcomes.

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

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

Hybrid Setting for Minimally Invasive Mitral Surgery in Patients With Inferior Vena Caval Filters

Current cardiac surgery has evolved to include hybrid and minimally invasive settings. In parallel, less invasive techniques have been extended to complex clinical scenarios and may prove even more beneficial in higher-risk patients. However, comorbidities and challenging anatomy still represent limitations to widespread application of this philosophy. Previously implanted filters in the inferior vena cava may limit the feasibility and safety of peripheral cannulation techniques. Successful minimally invasive operations in a hybrid setting in 2 patients with caval filters are reported.

Efficacy and safety of a novel vena cava filter on pulmonary embolism prophylaxis: a prospective, multicenter, randomized, parallel, positive-controlled, noninferiority clinical trial

Background

There are different types of vena cava filter (VCF) available in clinical practice. However, limited data exist to determine whether one type is superior to another, and no single VCF is universally recommended in clinical guidelines. The objective of this study was to investigate the safety and efficacy of a novel VCF, Octoparms, for the prevention of pulmonary embolism (PE) and to compare it with the Celect filter.

Methods

This multicenter, randomized, open-label, parallel, positive-controlled, noninferiority trial was conducted in 10 centers across 6 provinces in China from October 2017 to March 2019. Patients who had confirmed lower extremity deep vein thrombosis or PE or who were at risk of PE with a clinical indication for VCF placement due to contraindication to or failure of anticoagulant therapy were included in the trial. The sample size for this trial was based on the assumption that the clinical success rate would be 95% and the noninferiority margin would be 10% for both filters. Each patient underwent baseline testing and was randomized using a web-based central system. Any additional interventions or standard treatments patients received along with the VCF placement were recorded. The primary endpoint was the overall clinical success rate, including technical and clinical success of filter placement and retrieval. The secondary endpoint was the safety of filter placement and retrieval, encompassing procedure-related and filter-related complications.

Results

A total of 188 patients were included and were divided into two groups: the Octoparms group (n=94) and the Celect group (n=94). Baseline characteristics and demographics were comparable between the two groups (P>0.05). Technical and clinical success rates for filter placement were achieved in 100% (188/188) of patients. The median dwelling time was 12.0 days (range, 4-190 days). Ten VCFs were left in situ as permanent devices. Of the remaining 178 patients, technical success and clinical success rates for filter retrieval were both achieved in 100% of cases (178/178). Clinical success rates were 92.6% (87/94) for the Octoparms group and 96.8% (91/94) for the Celect group, with a difference of -4.2% (hazard ratio 2.441, 95% confidence interval 0.612-9.741; P=0.206). The lower limit was greater than the noninferiority margin of -10%. Eight patients experienced a total of eight procedure-related complications. No filter-related complications, such as migration, deformation, inferior vena cava (IVC) penetration, peripheral organ damage, or IVC stenosis/occlusion, were observed (P>0.05).

Conclusions

The Octoparms filter exhibited a high rate of clinical success and a low rate of complications during placement and retrieval, demonstrating noninferiority to the Celect filter.

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

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

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

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

Managing Patients With Concurrent High Risk for Bleeding and Thromboembolic Events

The number of patients with high bleeding risk (HBR) and high thromboembolic risk (HTR) is increasing. Gastrointestinal bleeding (GIH), acute coronary syndrome (ACS), and pulmonary embolism (PE) are representative conditions due to HBR/HTR. Although these disorders are located at opposite ends of the same disease spectrum, this does not mean a patient with HBR cannot have a concomitant HTR. The clinical manifestation of these two risks mostly results in critically ill patients for whom management means a huge challenge. We have numerous well-structured guidelines about treating GIH, ACS, or PE, but the literature and recommendations about the concomitant onset of these diseases are limited. Expert recommendations suggest an integrative, comprehensive assessment of patient and intervention-related factors to decide on the antithrombotic regimen with the best clinical benefit by assessing thrombotic and bleeding risks. In general, if thrombotic factors predominate, a longer duration, more aggressive antithrombotic regimen should be planned, and if bleeding susceptibility is higher, a shorter duration, de-escalated regimen should be pursued. In this study, we aimed to explore the clinical dilemmas involved by presenting two cases with delicate management.

AngioJet rheolytic thrombectomy coupled with dose-reduced rt-PA for massive inferior vena cava filter-related thrombosis: A single-center retrospective study

OBJECTIVE

To evaluate the efficacy and safety of AngioJet rheolytic thrombectomy (ART) coupled with dose-reduced rt-PA, compared to catheter-directed thrombolysis (CDT) alone, for the treatment of massive inferior vena cava filter (IVCF)-related thrombosis.

METHODS

We conducted a retrospective analysis of 40 patients who received either ART or CDT alone as the first-line endovascular therapy (ET) between January, 2016 and September, 2022. The data on demographics, clinical characteristics, technical success, clinical success, complications, and early follow-up were reviewed.

RESULTS

Of the 40 included patients, 24 received ART and 16 received CDT alone. The demographics, presentation, lesion characteristics, comorbidities and risk factors were comparable (all p > .05). Technical success rates were 100% in both groups. The total CDT time and infusion agent dosage were lower in the ART group than those in the CDT group (both p < .05). At the end of CDT, clinical success was 81.8% in the ART group, which was slightly higher than that of 70.8% in the CDT group (p > .05). At the 6-month follow-up, the incidences of recurrent thrombosis in the two groups were 6.9% and 15.8%, respectively, and the incidence of post-thrombotic syndrome was 10.3% and 21.1%, respectively. However, these differences were not statistically significant (p > .05). No major complications were noted in either group, ART seemed to have slightly higher risk of transient macroscopic hemoglobinuria and recoverable acute kidney injury, but with a lower minor bleeding incidence when compared with CDT alone (4.2 vs. 31.3%, p < .05).

CONCLUSIONS

ART or CDT alone as the first-line ET for IVCF-related thrombosis has comparable outcomes but with different adverse event profiles. Both modalities are safe and effective in patients with massive IVCF-related thrombosis.

Relationship between vascular access and angulation of vena cava filter at placement and retrieval: a multicenter retrospective cohort study

Background

Inferior vena cava (IVC) filters are commonly used intravascular devices designed to prevent fatal pulmonary embolism (PE), maintaining the IVC filter as centered as possible is fundamental for achieving its filtration function.

Objective

This study aimed to characterize the tilt angles of IVC filter between the vascular access of internal jugular vein (IJV) and femoral vein (FV), as well as to identify factors associated with increased or decreased tilt angles between placement and retrieval.

Design

This is a multicenter retrospective study.

Methods

A multicenter retrospective study was conducted from October 2017 to March 2019. The primary outcome was the change in filter tilt between placement and retrieval. The secondary outcome was the identifications of factors associated with increased or decreased tilt angle. Relevant variables were analyzed using t-tests, Chi-square tests, Fisher's exact tests, while multivariate logistic regression analysis was used to determine risk factors.

Results

A total of 184 eligible patients were included in this study. The IJV group had a lower likelihood of tilt angle over 10° at the time of placement compared to the FVs group (0% versus 12.5%, p = 0.040). Among the 171 patients with a mean dwell time of 22.1 days, the IJV group had a higher likelihood of tilt angle over 10° than the FVs group (10.3% versus 2.3%, p = 0.080). The use of FVs access at placement was associated with a higher difference between placement and retrieval filter tilt angles (p < 0.01). Multivariate logistic regression analysis showed that hypertension [odds ratio (OR) 0.668; 95% confidence interval (CI) 0.328-1.358, p = 0.265], cardiologic artery disease (OR 0.537; 95% CI 0.136-2.130, p = 0.377), cerebral venous disease (OR 0.555; 95% CI 0.186-1.651, p = 0.290), filter types (OR 1.624; 95% CI 0.851-3.096, p = 0.141), and IVC filter thrombosis (OR 1.634; 95% CI 0.804-3.323, p = 0.175) were not associated with increased filter tilt angle. Right side (OR 0.434; 95% CI 0.202-0.930, p = 0.032) or bilateral lower extremity deep vein thrombosis (LEDVT) (OR 0.383; 95% CI 0.148-0.995, p = 0.049) were identified as protective factors.

Conclusion

IJV access was associated with a lower filter tilt angle at the time of placement, while FVs access was linked to a higher difference between placement and retrieval tilt angles. Right side or bilateral LEDVT were identified as protective factors against increased IVC filter tilt angle.

Catheter-based therapies and short-term outcomes in the oncological patients with acute inferior vena cava thrombosis: a single centre experience

OBJECTIVE

To investigate the safety and effectiveness of catheter-based therapy (CBT) using AngioJet rheolytic thrombectomy (ART) device or large lumen catheter (LLC) in the oncological patients with inferior vena cava thrombosis (IVCT).

METHODS

This was a retrospective study including eligible patients with IVCT treated with CBT coupled with dose-reduced thrombolysis as the first-line treatment from February 1, 2015 to January 1, 2022. The baseline demographics, comorbidities, clinical characteristics, treatment details, course data were all reviewed.

RESULTS

A total of 33 patients (mean age 58.8 years, 57.6% male) was included, of whom 17 patients underwent ART and 16 underwent LLC aspiration, the technical success rates were 100%. All patients subsequently underwent catheter-directed thrombolysis relative to reduced-dose thrombolysis. At the end of catheter-directed thrombolysis, clinical success was achieved in 26 (78.8%) patients. In the subgroup analysis, ART seemed to receive a slightly higher rate of thrombus removal Grade III (47.1% vs 12.5%, p = .057). The symptoms of leg pain and swelling post-treatment were significantly improved in both groups (p < .001). Except for transient macroscopic hemoglobinuria occurring in patients with ART, none of all patients suffered from procedure-related adverse events and major complications. Minor complications such as bleeding events occurred in 6.1% (2/33) of patients. At the 6 month follow-up, the incidence of recurrent thrombosis and mild post-thrombotic syndrome (PTS) were 9.7% (3/31) and 6.5% (2/31).

CONCLUSION

CBT is a safe and effective modality for the management of IVCT in the oncological patients, leading to high levels of technical and clinical success, symptoms alleviation, as well as a low incidence of minor complication, mild PTS and recurrence.

ADVANCES IN KNOWLEDGE STATEMENT

The available data and evidence of endovascular therapy (ET) on oncologic patients with IVCT remains insufficient. The purpose of present single center retrospective study including 33 oncological patients is to investigate the preliminary safety and efficacy of CBT using ART device or LLC. The results demonstrated that CBTs are safe and effective as an ET modality in majority of eligible patients with symptomatic acute cancer-associated IVCT, indicating high levels of technical and clinical success, symptoms alleviation, as well as a low prevalence of minor complication, mild post-thrombotic syndrome and recurrence. Furthermore, they have the advantages of accelerated reduction of thrombus burden in a moderate time, speedy restoration of blood flow, but at the risk of potentially increased economic cost. Notably, in the condition of parallel time and dosages of lytic agents, ART tends to achieve a slightly higher thrombus removal Grade III than LLCA.