The Optional VenaTech? Convertible? Vena Cava Filter: Experimental Study in Sheep

Purpose

Retrieval of optional caval filters may be impaired by filter tilting, migration, fracture, or embedding in the IVC wall. The goal of this experimental study was to evaluate a new optional filter, convertible by unlocking and removing the filter head.

Methods

Forty-nine Pre-Alp sheep (average weight, 55?kg) were anesthetized. IVC was catheterized via the right femoral vein (n?=?46) or via the internal jugular vein (n?=?3) with a 12.9-F sheath. VenaTech^? Convertible^? IVC filters were inserted as either permanent filters (n?=?14)?or as filters to be converted. Conversion was immediately after deployment (n?=?19) or delayed after 1, 3, or 6?months (n?=?20). Filter delivery, deployment, and conversion with measurement of migration and tilting were evaluated by cavography. Incorporation of the filter’s stabilizers and arms in the IVC wall was assessed by gross anatomy.

Results

Delivery system insertion, filter release, and immediate conversion were successful in all cases. Delayed conversion was completed in all but one sheep, due to insufficient snare tension. Complimentary balloon-catheter inflation was required in 12 of 20 delayed conversions to achieve filter opening. In all 49 sheep, no thrombosis, migration, or significant tilting occurred. Within 4?weeks of conversion, the filter’s stabilizers and arms were incorporated into the IVC wall. Upon removal, the filter head was free of intimal growth.

Conclusions

The VenaTech^? Convertible^? optional IVC filter was successfully implanted in all sheep with no migration or tilting. Conversion at various dates by filter head removal was feasible in all but one case.     

Significant Caval Penetration by the Celect Inferior Vena Cava Filter: Attributable to Filter Design?

This report describes transmural penetration of the inferior vena cava (IVC) by a newly introduced IVC filter within 9 days of its placement. A computed tomographic study demonstrated filter penetration with one of the primary struts lodging in the uncinate process of the pancreas. Because of the close resemblance of this new filter to another filter that has not been associated with penetration injuries, the key differences between the two designs were examined and the determination was made that the new filter, unlike the older one, has unprotected primary struts. Only filters with an unprotected primary strut design have been associated with penetration injuries such as the one described in this case.     

Factors Associated with Advanced Inferior Vena Cava Filter Removals: A Single-Center Retrospective Study of 203 Patients Over 7 Years

Purpose

To identify factors associated with advanced inferior vena cava filter (IVCF) retrieval to raise awareness on technical considerations, retrieval efficiency, and patient safety.

Materials and Methods

A single-center retrospective review was performed of 203 consecutive retrievable IVC filters placed between 2007 and 2014. Attempted retrievals were classified as advanced if the routine “snare and sheath” technique was initially unsuccessful after multiple attempts, or an alternate endovascular maneuver or access site was utilized. Patient and filter characteristics were recorded.

Results

203 attempted retrievals were reviewed (48.7 % male, 51.2 % female, mean age 52.7 years, mean dwell time 109 days). Advanced retrievals were observed in 20 patients (9.8 %) (15 females, 5 males). Fluoroscopy time (p ≤ 0.01, 34.3 ± 21.1 and 5.3 ± 4.5 min for advanced retrievals and routine retrievals respectively, same below), gender (p = 0.031), and retrieval tilt angle (p ≤ 0.01, 5.7 ± 5.10° vs. 11.9 ± 11.03°) were associated with advanced retrievals. Females were 3.16 times more likely to have an advanced retrieval performed than males with a significantly higher tilt angle in those with advanced retrieval. History of cancer (p = 0.502), dwell time (p = 0.916), retrieval caval diameter (p = 0.053), placement caval diameter (p = 0.365), filter type (p = 0.710), strut perforation (p = 0.506), placement tilt angle (p = 0.311), and age (p = 0.558) were not found significantly associated with advanced retrievals.

Conclusions

Women are at increased risk for advanced filter retrieval secondary to a significant change in filter tilt over time compared to men, independent of filter type or competing demographic or filter risks, likely placing them at increased risk for higher procedural fluoroscopy times.

     

Long-Term Safety and Effectiveness of the ��OptEase�� Vena Cava Filter

Purpose  

To assess the long-term safety and effectiveness of the OptEase inferior vena cava (IVC) filter.     

Temporary and Permanent Inferior Vena Cava Filter Combination in a Young Patient: To Implant or Not to Implant?

The decision to implant vena cava filters, either temporary or permanent, is difficult in young patients. We present the case of a young man with pulmonary embolism in whom temporary and permanent inferior vena cava filters were implanted. The decision process is discussed in relation to the current literature.     

Endovascular Iliocaval Stent Reconstruction for Inferior Vena Cava Filter–Associated Iliocaval Thrombosis: Approach,Technical Success,Safety, and Two-Year Outcomes in 120 Patients

Purpose

To report technical success, outcomes, and patency of iliocaval stent reconstruction for inferior vena cava (IVC) filter–bearing iliocaval thrombosis.

Bird’s Nest Filter Causing Symptomatic Hydronephrosis Following Transmural Penetration of the Inferior Vena Cava

We report a case of symptomatic hydronephrosis caused by transcaval penetration of a Birds Nest filter. Perforation of the wall of the inferior vena cava (IVC) following insertion of a caval filter is a well-recognized complication. Whilst two cases of hydronephrosis have been described with Greenfield filters, no case involving a Birds Nest filter has been reported previously.     

Retrievable Günther Tulip Vena Cava Filter in the prevention of pulmonary embolism in patients with acute deep venous thrombosis in perinatal period

Objectives

To evaluate the feasibility and efficacy of the retrievable Günther Tulip Vena Cava Filter in the prevention of pulmonary embolism in patients with acute deep vein thrombosis in the perinatal period and to discuss the technical demands associated with the filter's implantation and retrieval.

Methods

Between 1996 until 2007, eight women (mean age 27.4 years, range 20–42 years) with acute deep iliofemoral venous thrombosis in the perinatal period of pregnancy and increased risk of pulmonary embolism during delivery were indicated for retrievable Günther Tulip Vena Cava Filter implantation. All filters were inserted and removed under local anesthesia from the jugular approach.

Results

The Günther Tulip Vena Cava Filter was implanted suprarenally in all patients on the day of caesarean delivery. In follow-up cavograms performed just before planned filter removal, no embolus was seen in the filter in any patient. In all patients the filter was retrieved without complications on the 12th day after implantation.

Conclusions

Retrievable Günther Tulip Vena Cava Filters can be inserted and removed in patients during the perinatal period without major complications.     

Günther Tulip Retrievable Vena Cava Filter: results from the Registry of the Canadian Interventional Radiology Association

PURPOSE: To report data collected by the Canadian Registry of the Günther Tulip Retrievable Filter (GTF). MATERIALS AND METHODS: Between February 1998 and December 2000, 90 patients at eight hospitals underwent implantation of 91 GTFs. There were 45 male patients and 45 female patients, age 17-88 years, with a mean age of 49 years. Indications for filter placement were pulmonary embolism (PE) or deep vein thrombosis (DVT) with a contraindication to anticoagulation in 83 patients, prophylaxis after massive PE in one, prophylaxis for proximal free-floating thrombus in one, and prophylaxis with no DVT or PE in six patients (major trauma, n = 4; high preoperative risk, n = 2). GTF retrieval was attempted in selected patients from a right internal jugular vein approach. RESULTS: One GTF was inadvertently placed in the right iliac vein and could not be retrieved. There were no other major placement complications. GTF retrieval was attempted in 52 patients (53 GTFs); 52 GTFs were successfully retrieved from 51 patients. Implantation times were 2-25 days (mean, 9 d). Of these 51 patients, 37 underwent follow-up for 5-420 days (mean, 103 d) after filter retrieval. Four patients (8% of retrieved GTFs) required reinsertion of a permanent filter 17-167 days (mean, 78 d) after GTF retrieval as a result of bleeding from anticoagulation (n = 2) or because the patient required further surgery (n = 2). One other patient had recurrent DVT 230 days after retrieval; no PE or other complication was documented in the retrieval group. GTFs were not retrieved from 39 patients for various reasons. Of these 39 patients, 25 underwent follow-up 7-420 days (mean, 85 d) after filter placement. Two patients developed filter occlusion (5%); no other complications were documented. CONCLUSION: The GTF has a broad range of utility: it can be used as a permanent filter or retrieved after implantation periods of 15 days and possibly longer. However, indications for retrieval require further study, as does the maximum implantation time.     

Introducer Curving Technique for the Prevention of Tilting of Transfemoral G��nther Tulip Inferior Vena Cava Filter

Objective

To determine whether the introducer curving technique is useful in decreasing the degree of tilting of transfemoral Tulip filters.

Materials and Methods

The study sample group consisted of 108 patients with deep vein thrombosis who were enrolled and planned to undergo thrombolysis, and who accepted transfemoral Tulip filter insertion procedure. The patients were randomly divided into Group C and Group T. The introducer curving technique was Adopted in Group T. The post-implantation filter tilting angle (ACF) was measured in an anteroposterior projection. The retrieval hook adhering to the vascular wall was measured via tangential cavogram during retrieval.

Results

The overall average ACF was 5.8 ± 4.14 degrees. In Group C, the average ACF was 7.1 ± 4.52 degrees. In Group T, the average ACF was 4.4 ± 3.20 degrees. The groups displayed a statistically significant difference (t = 3.573, p = 0.001) in ACF. Additionally, the difference of ACF between the left and right approaches turned out to be statistically significant (7.1 ± 4.59 vs. 5.1 ± 3.82, t = 2.301, p = 0.023). The proportion of severe tilt (ACF ≥ 10°) in Group T was significantly lower than that in Group C (9.3% vs. 24.1%, χ² = 4.267, p = 0.039). Between the groups, the difference in the rate of the retrieval hook adhering to the vascular wall was also statistically significant (2.9% vs. 24.2%, χ² = 5.030, p = 0.025).

Conclusion

The introducer curving technique appears to minimize the incidence and extent of transfemoral Tulip filter tilting.     

One-Year Analysis of the Prospective Multicenter SENTRY Clinical Trial: Safety and Effectiveness of the Novate Sentry Bioconvertible Inferior Vena Cava Filter

Purpose

To prospectively assess the Sentry bioconvertible inferior vena cava (IVC) filter in patients requiring temporary protection against pulmonary embolism (PE).

Complications of Celect,Günther Tulip,and Greenfield Inferior Vena Cava Filters on CT Follow-up: A Single-Institution Experience

PurposeTo evaluate and compare the rates of complications on follow-up computed tomography (CT) studies of patients with Celect, Günther Tulip, and Greenfield inferior vena cava (IVC) filters.Materials and MethodsRetrospective review of CT studies obtained 0–1,987 days after infrarenal placement of an IVC filter identified 255 Celect, 160 Tulip, and 50 Greenfield filters. Follow-up CT studies were independently evaluated by two observers for IVC perforation, contact with adjacent organs, and filter fracture. Multivariate analysis was performed to identify factors associated with higher rates of IVC perforation, including age, IVC diameter, sex, and history of malignancy.ResultsIVC perforation was observed in 126 of 255 Celect filters (49%) with a mean follow-up of 277 days, 69 of 160 Tulip filters (43%) with a mean follow-up of 437 days, and one of 50 Greenfield filters (2%) with a mean follow-up of 286 days. A significantly higher IVC perforation rate was observed in women (45.5%) compared with men (30.8%; P = .002) and in patients with a history of malignancy (43.7%) compared with patients with no history of malignancy (29.9%; P < .001). Filter fracture was rare, observed in two of 255 Celect filters (0.8%), one of 160 Tulip filters (0.6%), and none of 50 Greenfield filters.ConclusionsNo significant difference was observed in IVC perforation rate between Celect and Tulip filters. Greenfield filters had a significantly lower rate of IVC perforation than Celect and Tulip filters. Higher IVC perforation rates were observed in women and patients with a history of malignancy.     

Retrograde Tempofilter II? Placement within the Superior Vena Cava in a Patient with Acute Upper Extremity Deep Venous Thrombosis: the Filter Stands on Its Head

The Tempofilter II is a widely used temporary vena cava filter. Its unique design, which includes a long tethering catheter with a subcutaneous anchor, facilitates the deployment and retrieval of the device. Despite this, the Tempofilter II has been used only in the inferior vena cava of patients with lower extremity deep venous thrombosis. In this article, we present a case of superior vena cava filtering using the Tempofilter II in patients with upper extremity deep venous thrombosis.     

Evaluation of a Device Combining an Inferior Vena Cava Filter and a Central Venous Catheter for Preventing Pulmonary Embolism Among Critically Ill Trauma Patients

Purpose

To evaluate efficacy and safety of a novel device that combines an inferior vena cava (IVC) filter and central venous catheter (CVC) for prevention of pulmonary embolism (PE) in critically ill patients.

Compression of the Inferior Vena Cava by the Right Iliac Artery: A Rare Variant of May–Thurner Syndrome

May–Thurner syndrome is known as compression of the left common iliac vein by the right common iliac artery. We describe a case of an atypical compression of the inferior vena cava by the right common iliac artery secondary to a high aortic bifurcation. Despite an extensive collateral network, there was a significant venous gradient between the iliac veins and the inferior vena cava above the compression. After stenting the venous pressure gradient disappeared. Follow-up 4 months later revealed a good clinical response with a patent stent.     

Covered Stent Placement for the Treatment of Malignant Superior Vena Cava Syndrome: Is Unilateral Covered Stenting Safe and Effective?

Objective

To evaluate the safety and efficacy of unilateral covered stent placement in patients with malignant superior vena cava (SVC) syndrome.

Materials and Methods

Between October 2008 and November 2012, expanded polytetrafluoroethylene-covered stent placement for malignant SVC syndrome was performed in 40 consecutive patients (35 men and five women; mean age, 61.4 years; range, 35-81 years). All covered stents were unilaterally placed within the SVC or across the venous confluence when needed to relieve venous obstruction and prevent tumor overgrowth, regardless of patency of contralateral brachiocephalic veins.

Results

Stent placement was technically successful in all patients. There were no major complications. Of the 37 patients symptomatic prior to stent placement, 34 (92%) experienced complete symptomatic relief 1-8 days after stent placement. Of the 29 patients who underwent covered stent placement across the venous confluence, nine patients had patent contralateral brachiocephalic veins prior to stent placement. However, no sign of SVC obstruction or contralateral upper extremity venous thrombosis was observed during the follow-up period. Kaplan-Meier analysis revealed median patient survival of 163 days. Stent occlusion occurred in four (10%) of 40 patents. Cumulative stent patency rates at 1, 3, 6, and 12 months were 95%, 92%, 86%, and 86%, respectively.

Conclusion

Unilateral covered stent placement appears to be a safe and effective method for treating malignant SVC syndrome, despite the location of SVC occlusion.     

Percutaneous Endovascular Creation of an Inferior Vena Cava in a Patient with Caval Agenesis,Budd–Chiari Syndrome,and Iliofemorocaval Thrombosis

A 29-year-old woman with acute iliofemorocaval thrombosis was discovered to have suprarenal caval agenesis with azygous continuation, hepatic congestion, and fibrosis as a result of chronic Budd–Chiari syndrome. Three staged procedures were performed: pharmacomechanical thrombolysis of acute thromboses, transfemoral liver biopsy and hemodynamic assessment, and percutaneous endovascular creation of a “neocava” lined with endografts. Symptomatic improvement and patency were maintained at 12-week follow-up.