Immediate and Delayed Complications of IVC Filters

Clinical effect of catheter-directed thrombolysis combined with intermittent pneumatic compression on lower extremity deep venous thrombosis

AIM

This study investigated the effectiveness of catheter-directed thrombolysis (CDT) combined with intermittent pneumatic compression (IPC) in patients with lower extremity deep venous thrombosis (LEDVT).

MATERIALS AND METHODS

A retrospective analysis was conducted on 68 LEDVT patients. Those who received CDT with IPC were assigned to the IPC group, while those who underwent CDT alone were designated as the control group. Both groups were further divided into early and late subgroups based on the time from symptom onset to CDT. Data collected included the cumulative urokinase dosage, CDT duration, and other relevant clinical indicators.

RESULTS

The cumulative urokinase dosage was lower in the IPC group than in the control group (P<0.05). CDT duration was shorter in the IPC group than in the control group and was also shorter in the early subgroup compared with the late subgroup (all P<0.05). The peak D-dimer occurred earlier in the IPC group than in the control group (P<0.05). The incidence of grade II-III thrombolysis was higher in the IPC group than in the control group on days 2 and 3 of CDT (all P<0.05). The IPC group showed a greater reduction in thigh and calf circumference than the control group on days 3 and 4 of CDT (all P<0.05).

CONCLUSIONS

In LEDVT patients, CDT combined with IPC reduced the cumulative urokinase dosage, shortened CDT duration, promoted earlier deep vein patency, and accelerated the relief of lower extremity swelling.

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.

The Degree of Inferior Vena Cava Filter Tilt Associated with Challenging Retrieval

BACKGROUND

Inferior vena cava (IVC) filter tilt is associated with technical difficulties at the time of retrieval. However, the degree of tilt that predisposes patients to undergo complex or failed retrieval has not been defined.

METHODS

The electronic charts of patients undergoing IVC filter removal between 2010 and 2019 at a single tertiary center were reviewed. Patient and procedural characteristics were recorded. Venograms of placement and retrieval procedures were reviewed, and IVC filter tilt was determined based on its deviation from the IVC axis. IVC diameter and the distance from the lowest renal vein were measured using corresponding filter's length for calibration. All measurements were performed by 3 reviewers and confirmed by 2 reviewers. Patients were divided into 2 groups: those who underwent successful removal procedures requiring standard retrieval methods ("simple retrieval group") and those who required advanced endovascular techniques or had failed completely IVC filter retrievals ("challenging retrieval group"). A regression analysis was performed to determine factors associated with challenging retrieval.

RESULTS

There were 365 patients who underwent IVC filter retrieval (n = 294 (80.6%) and n = 71 (19.4%) in the simple and challenging groups, respectively) with no difference in age, sex, comorbidities, or indication between the 2 groups. Failed retrieval occurred in 21 patients (5.8%) and was more common among patients requiring advanced endovascular techniques compared to standard techniques (18.0% vs. 3.2%, P < 0.001). In the overall cohort, the mean filter tilt at the time of retrieval was 4.9° ± 4.4° [0c27°], and 145 patients (39.7%) had a filter tilt ≥5.0°. Compared to the simple retrieval group, patients in the challenging group had significantly longer dwell time, greater tilt of IVC filter during placement and retrieval, as well as higher tilt change between the 2 venograms. There was no correlation between the access site during placement and challenging retrieval. However, patients undergoing filter placement via right jugular vein had lower filter tilt as compared to femoral access. Patients with filter tilt ≥5.0° were more likely to have a challenging filter retrieval compared to patients with ˂5.0° tilt (29.7% vs. 12.7%, P < 0.001). Regression analysis showed that tilt ≥5.0° (odds ratio [OR] = 1.18 [1.11-1.25]), dwell time (OR = 1.04 [1.01-1.07]), and age (OR = 0.97 [0.95-0.99]) were independently associated with challenging retrieval.

CONCLUSIONS

IVC filter tilt ≥5.0°, dwell time and age are associated with challenging retrieval. Right jugular vein access, multiple imaging projections, and careful filter manipulation during deployment should be considered to maintain tilt at ˂ 5.0° and decrease the likelihood of challenging retrieval.

Predicting inferior vena cava filter complications using machine learning

OBJECTIVE

Inferior vena cava (IVC) filter placement is associated with important long-term complications. Predictive models for filter-related complications may help guide clinical decision-making but remain limited. We developed machine learning (ML) algorithms that predict 1-year IVC filter complications using preoperative data.

METHODS

The Vascular Quality Initiative database was used to identify patients who underwent IVC filter placement between 2013 and 2024. We identified 77 preoperative demographic and clinical features from the index hospitalization when the filter was placed. The primary outcome was 1-year filter-related complications (composite of filter thrombosis, migration, angulation, fracture, and embolization or fragmentation, vein perforation, new caval or iliac vein thrombosis, new pulmonary embolism, access site thrombosis, or failed retrieval). The data were divided into training (70%) and test (30%) sets. Six ML models were trained using preoperative features with 10-fold cross-validation (Extreme Gradient Boosting, random forest, Naïve Bayes classifier, support vector machine, artificial neural network, and logistic regression). The primary model evaluation metric was area under the receiver operating characteristic curve (AUROC). Model robustness was assessed using calibration plot and Brier score. Performance was evaluated across subgroups based on age, sex, race, ethnicity, rurality, median Area Deprivation Index, planned duration of filter, landing site of filter, and presence of prior IVC filter placement.

RESULTS

Overall, 14,476 patients underwent IVC filter placement and 584 (4.0%) experienced 1-year filter-related complications. Patients with a primary outcome were younger (59.3 ± 16.7 years vs 63.8 ± 16.0 years; P < .001) and more likely to have thrombotic risk factors including thrombophilia, prior venous thromboembolism (VTE), and family history of VTE. The best prediction model was Extreme Gradient Boosting, achieving an AUROC of 0.93 (95% confidence interval, 0.92-0.94). In comparison, logistic regression had an AUROC of 0.63 (95% confidence interval, 0.61-0.65). Calibration plot showed good agreement between predicted/observed event probabilities with a Brier score of 0.07. The top 10 predictors of 1-year filter-related complications were (1) thrombophilia, (2) prior VTE, (3) antiphospholipid antibodies, (4) factor V Leiden mutation, (5) family history of VTE, (6) planned duration of IVC filter (temporary), (7) unable to maintain therapeutic anticoagulation, (8) malignancy, (9) recent or active bleeding, and (10) age. Model performance remained robust across all subgroups.

CONCLUSIONS

We developed ML models that can accurately predict 1-year IVC filter complications, performing better than logistic regression. These algorithms have potential to guide patient selection for filter placement, counselling, perioperative management, and follow-up to mitigate filter-related complications and improve outcomes.

Unveiling the Link: Minimum Inferior Vena Cava Diameter and Thrombosis Risk

RATIONALE AND OBJECTIVES

This study aimed to investigate the relationship between minimum inferior vena cava (IVC) diameter magnification percentage and in-situ IVC thrombosis (iIVCT) after inferior vena cava filter (IVCF) placement in lower extremity deep vein thrombosis (LEDVT).

METHODS

This was a single center retrospective study. Study sample consisted of patients with LEDVT who received computed tomography venography of IVC both before and after IVCF placement between January 2019 and October 2023. A propensity score matching (PSM) was also used in covariates including age, hypertension, and thrombus limbs. Multivariate Cox regression analyses were performed to mitigate the impact of selection bias and control for potential confounding variables. The incremental changes associated with minimum IVC diameter magnification percentage and iIVCT were evaluated with restricted cubic spines (RCS).

RESULTS

113 LEDVT patients (age 58.8 ± 17.8 years, 57.5% male) were included. Multivariate Cox regression analyses revealed a significant positive association between the minimum IVC diameter magnification percentage and the incidence of iIVCT after adjusting for the age, hypertension, and thrombus limbs (adjusted hazard risk [HR] = 1.02, 95% CI, 1.01 to 1.02, p < .001), suggesting minimum IVC diameter magnification percentage was an independent risk factor for iIVCT. Moreover, after using PSM, the association remained significant (HR=1.01, 95% CI, 1.01 to 1.02, p < .001). RCS analysis showed a non-linear dose-response association (s-shaped fitting curve) between minimum IVC diameter magnification percentage and iIVCT risk (nonlinear p = .041). The fitting curve indicated a threshold effect (overall p = .005), with a smaller magnification percentage being negatively associated with the incidence of iIVCT, presenting continuously decreasing HR at levels of magnification percentage < 37.3%.

CONCLUSION

A decreasing minimum IVC diameter magnification percentage is consistently associated with a decreasing risk of iIVCT following IVCF placement when the percentage is < 37.3%, indicating that it is a protective factor against iIVCT incidence. WHAT THIS PAPER ADDS?: This single-center retrospective study, which designed to investigate the relationship between minimum inferior vena cava diameter magnification percentage and in-situ inferior vena cava thrombosis (iIVCT) following inferior vena cava filter (IVCF) placement in lower extremity deep vein thrombosis in 113 patients, demonstrated that decreasing minimum IVC diameter magnification percentage is consistently associated with a decreasing risk of iIVCT following IVCF placement when the percentage is < 37.3%, indicating that it is a protective factor against iIVCT incidence.

Placing two inferior vena cava filters for the bail-out management of opening failure of an inferior vena cava filter

A 93-year-old man with a femoral fracture was admitted to the emergency department. The patient presented with severe hypoxemia and shock. Enhanced computed tomography confirmed deep venous thrombosis in the left leg and pulmonary embolism. Subsequently, an inferior vena cava filter (IVCF) was implanted. Although the IVCF was completely unsheathed for deployment, it remained fully folded and did not open; it was not deployed or retrieved. A new IVCF was successfully placed in the same position. Acute treatment for the deep venous thrombosis and further pulmonary embolism was achieved.

Retrieval of an inferior vena cava Greenfield filter 34 years after insertion

Inferior vena cava (IVC) filters are engineered medical devices deployed in the IVC primarily to prevent a pulmonary embolism from occurring. In this article, we present a case of an IVC filter that was successfully retrieved from a patient after being in place for 34 years. The patient presented to hospital for trauma in which subsequent imaging showed tines of an IVC filter protruding outside of the vessel with one of the tines penetrating the duodenal wall. The filter was successfully removed with no complications. This report adds to the existing literature by yielding an example of an adverse risk that can be associated with the placement of IVC filters. In addition, to the authors' best knowledge, this is the longest reported length of time that an IVC filter has stayed in a patient before being removed, thus adding another intriguing detail to the case.

Application of the Double Series Filter Technique for the Treatment of Acute Inferior Vena Cava Filter-Mediated Thrombosis

BACKGROUND

In this study, we examined the safety and effectiveness of removing inferior vena cava (IVC) filters with residual acute thrombosis after endovascular therapy.

METHODS

A retrospective chart review of 712 patients who underwent retrievable IVC filter implantation between July 2018 and December 2022 was conducted. Residual thrombosis with the IVC filter occurred in 18 patients, and the volume of residual acute thrombosis in the IVC filter exceeded 1 mL in all cases. Angiography was performed to evaluate the size of the residual thrombosis and its position with respect to the filter. The double series filter technique (first filter, infrarenal IVC filter; second filter, suprarenal IVC filter) was used to remove the filter and thrombosis. We summarize the diagnosis, treatment, and surgical experience of these patients.

RESULTS

In this study, 16 of 18 patients (88.9%) demonstrated residual thrombosis in the IVC filter. One patient (5.6%) demonstrated thrombosis located both inside and floating above the filter, and one patient (5.6%) demonstrated thrombosis located both inside and underneath the filter. The technical success rate of double series IVC filter retrieval was 100%. Seventeen patients (94.4%) underwent single-stage suprarenal IVC filter retrieval, and one patient (5.6%, 1/18) underwent two-stage retrieval. In terms of residual thrombosis removal, 14 patients (77.7%) achieved complete removal and 4 patients (22.3%) achieved partial removal. Residual thrombosis could not be removed through the sheath in one patient, so femoral vein thrombectomy was performed. No other procedure-related complications were observed. The median follow-up time was 22.5 ± 6.8 months. No recurrence of thrombus symptoms was reported, and B ultrasound and computed tomography demonstrated smooth blood flow in the IVC, renal veins, and pulmonary artery.

CONCLUSIONS

For patients with residual acute thrombosis on the IVC filter and in whom there was absence of a more appropriate treatment after percutaneous mechanical thrombectomy or catheter-directed thrombolysis therapy, the double series IVC filter technique was a safe approach to improve the IVC filter retrieval rate in the early stage, as well as for simultaneous residual thrombus removal.

Inferior Vena Cava Filters and Complications: A Systematic Review

Inferior vena cava (IVC) filters have been used since the 1960s to treat patients with acute risk of pulmonary embolism (PE) to prevent migration of thrombus by trapping it within the filter. Traditional usage has been in patients with contraindication to anticoagulation that carry a significant mortality risk. In this systematic review, we sought to evaluate complications associated with placement of inferior vena cava filters based on published data from the past 20 years. A search was performed on October 6th, 2022, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for systematic reviews, using three databases (ProQuest, PubMed and ScienceDirect) for articles published between the dates of February 1, 2002 and October 1, 2022. Results were filtered to include full-text, clinical studies, and randomized trials written in English pertaining to keywords "IVC filter AND complications", "Inferior Vena Cava Filter AND complications", "IVC filter AND thrombosis" and "Inferior Vena Cava Filter AND thrombosis". Articles identified by the three databases were pooled and further screened for relevance based on inclusion and exclusion criteria. Initial search results yielded 33,265 hits from all three databases combined. Screening criteria were applied, with 7721 results remaining. After further manual screening, including removal of duplicate hits, a total of 117 articles were selected for review. While there are no consensus guidelines for best practice, there is compelling evidence that IVC filters can provide significant protection against PE with minimal complications if the treatment window is appropriate. Increase in the variety of filter models has led to broader availability, but skepticism remains about their efficacy and safety, with ongoing controversy surrounding appropriate indications. Further research is needed to establish clear guidelines on appropriate indications for IVC placement and to determine time course of complications versus benefits for indwelling filters.

Conservative Management of Duodenal Penetration by Inferior Vena Cava Filter: Case Report and Review

Duodenal penetration is a late complication associated with the placement of inferior vena cava (IVC) filters. In this case report, we are presenting a case of asymptomatic duodenal penetration by IVC filter that was managed conservatively.