Inferior Vena Cava Filter Placement Research Articles

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.

Inferior Vena Cava Filters as a Potential Non-immune Cause of Low Serum Haptoglobin

Objective: Serum haptoglobin level is commonly used as a marker of hemolysis. We hypothesized that inferior vena cava (IVC) filters may be a potential non-immune etiology for subclinical hemolysis and low haptoglobin in some patients, after encountering a patient with an IVC filter, mild macrocytic anemia and unexplained severe haptoglobinemia. IVC filters can be associated with pressure gradients and turbulent blood flow in the presence of trapped clots and thrombus formation. Methods: Prospective study in patients undergoing IVC filter placement at our institution over a 3-month period in 2008. All patients had a haptoglobin level prior to filter placement, and then daily for a period of 3-14 days. The absolute and relative change in haptoglobin compared to pre-procedure levels was determined. Results were evaluated by t-test (paired, 2-tail). Statistics and graphics were performed with commercial software. Results: A total of 22 patients underwent IVC filter placement. Four patients were excluded due to low preprocedure haptoglobin levels. At least one post-procedure haptoglobin values was available until day 3 in 18/18 eligible patients. Nine patients were followed for a period of 1-2 weeks. Although the majority of patients had an increase in haptoglobin after IVC filter placement, 3/9 (30%) had >50% decrease in haptoglobin by day 7, including one patient with severe haptoglobinemia by day 14. Patients with decreased haptoglobin levels also had decreases in platelet count over the same period. Conclusion: These results suggest that IVC filters may be another non-immune, device-related cause of decreased haptoglobin in some patients.

Inferior Vena Cava Filter (IVCF) Placement in a Community Hospital: Adherence to Guidelines, Retrieval Rates, and Complications

Background: IVCF use has been increasing in recent years (Stein et al., Am J Med 2011) and published work demonstrates that a significant proportion of IVCF placements are performed for prophylaxis rather than for therapeutic indications (63.4% Swami et al. Clin Appl Thromb Hemost 2014 and 41.7% Rottenstreich et al. Eur J Haematol 2015). We studied the patterns of the IVCF use, rate of filter retrieval and complications associated with IVCF use in a community hospital.Methods: Between 2010 and 2014 a total of 145 patients (92 males, 53 females) with median age of 69 years (range 20- 98), received an IVCF at a 254-bed community hospital. All of these patients' charts were reviewed and the indications for IVCF placement, types of filters used, retrieval rates, and complications were assessed for adherence to published guidelines (Caplin et al., J Vasc Interv Radiol 2011). IVCF use in cancer patients were assessed separately.Results: All of the 145 filters used at this hospital were designed to be retrievable. The median duration of follow up after IVCF placement was 27.4 months. Gunther Tulip and Bard Denali filters were used most frequently (65.5% and 27.5% respectively). Of the 145 filters placed, 103 (71%) were used in patients with accepted therapeutic indications. These 103 patients included 84 with bleeding on anticoagulant (AC), 12 pts with venous thromboembolic event (VTE) undergoing surgery, 2 with VTE on anticoagulation (AC), and 5 undergoing thrombolysis. Other therapeutic indications for use of IVCF placement included decreased cardiopulmonary reserve in 3, inability to achieve therapeutic levels of anticoagulation in 8, medical comorbidities with high risk of falls in 5, and poor compliance with medications in 2 patients.Twenty one (14.5%) patients underwent IVCF placement after deep venous thrombosis (DVT) or pulmonary embolism (PE) without any obvious contraindications to AC. Of the 145 filters inserted, only 22 (15.2%) were retrieved. Filters remained in place for a median of 91 days (range 20 - 365). No complications were encountered during the removal.Among the patients who received an IVCF, 27 (18.6%) had an underlying cancer. Therapeutic indications for IVCF use were found in 24 (88.9%) of these patients. These included bleeding in 15 patients, primary brain cancer or brain metastases in 8, and DVT despite high INR in 1. In cancer patients 3 of the 27(11.1%) filters placed were retrieved. Differences in the rates of filter placement for therapeutic indications and retrieval rates between cancer and non-cancer patients were not statistically significant.Complications of IVCF were mainly thrombotic with propagation of DVT in 21 (14.5%) patients, PE in 8, and clot in the IVCF in 3 pts. These numbers exclude thrombotic complications which occurred in the first 7 days after IVCF placement, as we considered that they could be a consequence of the initial thrombotic event unrelated to the presence of the filter. Non- thrombotic complications included three patients with IVC penetration and one in whom migration of the filter caused duodenal perforation and bleeding.Conclusions: Our results demonstrate that 71% of the IVC filters in our community hospital are placed for therapeutic indications. This compares favorably to the observations of Swami et al.(op.cit.) who found that only 36.6% of patients met therapeutic criteria for filter placement, and Rottenstreich et al.(op.cit.) who reported therapeutic reasons for placement in 58.3%. Elucidation of the factors which led to the high compliance rate reported here could result in improvement of general practice patterns. It is noteworthy that high adherence to guidelines for IVCF placement was found in patients with an underlying diagnosis of cancer (88.9%).In general, the rate of filter retrieval was low (15.2% overall and 11.1% in cancer patients) and needs improvement. More emphasis on measures to improve the rate of IVCF retrieval is warranted. DisclosuresNo relevant conflicts of interest to declare.

Inferior Vena Cava Filter - Appropriate Use and Retrieval

Inferior vena cava (IVC) filters, first introduced in 1998, have been utilized to reduce risk of pulmonary embolism (PE) in the setting of an inability to anticoagulate patients. The use of IVC filters has increased and continues to rise, especially with the introduction of retrievable IVC filters. Since their initial introduction, guidelines have been developed on the appropriate use of IVC filters. According to the American College of Chest Physicians (ACCP), the use of an IVC filter is limited to patients with an absolute contraindication to therapeutic anticoagulation or failure or complication of anticoagulation in the setting an acute proximal venous thrombus. Relative indications for IVC filter placement include high clot burden in setting of low cardiopulmonary reserve, high risk patients, or severe trauma without documented thrombosis. In 2010, the FDA announced a safety communication recommending removal of retrievable IVC filters due to reports of several adverse clinical outcomes associated with retained filters including thrombus formation, recurrent PE, filter migration, erosion or perforation through the IVC wall, and filter fracture with fragment embolization. In 2014, the FDA recommended removal of the IVC filter within 2 months after filter placement if the patient's risk of thrombosis had passed.In this retrospective analysis of IVC filter management, we reviewed indications for placement according to current guidelines as set by the ACCP, initiation of appropriate anticoagulation, complication rates, and retrieval rates. In addition, we compared the data prior to the FDA recommendations in late 2014 and data after the recommendations to determine if there was a change in practice.After reviewing 179 patients, 89 patients in 2014 and 90 patients in 2015, who underwent IVC filter placement, only 81% (N=145) of patients had appropriate indications for IVC filter placement and 30% (N=54) of patients had inappropriate anticoagulation after IVC filter placement, given as prophylactic dosing of low molecular weight heparin. A comparison of retrieval rates prior to and after the FDA warning, showed a 19% (60% in 2014 vs 79% in 2015) improvement in IVC filter removals. There was an 11% complication rate, mainly related to IVC filter related acute DVT or IVC occlusion.A root cause analysis specifically for inappropriate IVC filter placement and appropriate anticoagulation and determined that familiarity of the guidelines and non-evidence based recommendations from consultants were major factors. Based on the analysis, we next plan to utilize the electronic health record system to help clinicians understand indications and when to initiate appropriate anticoagulation, with the opportunity for hematology consultants to be involved in situations that do not clearly fit within published guidelines. DisclosuresNo relevant conflicts of interest to declare.

Strategies to Improve Safety and Outcomes Utilizing Systems-Based Hematologists in IVC Filter Placement and Management in an Academic Medical Center

In large academic institutions, there are multiple disciplines and clinical scenarios that may require placement of inferior vena cava filters (IVCF). Both the Society of Interventional Radiology (SIR) and the American College of Chest Physicians (ACCP) have released guidelines for IVCF use, with the ACCP guidelines being more stringent due to the lack of survival benefit supported by level I data. Several publications have reported high rates of retrievable IVCF complications. In response to these risks and low retrieval rates, the U.S. FDA issued an updated safety alert in 2014 recommending that implanting physicians and clinicians responsible for the ongoing care of patients with retrievable IVCF consider removing the filter as soon as protection from pulmonary embolism is no longer needed.A systems-based hematologist (SBH) plays a vital role in navigating the health care system in the use of therapeutic and device agents that crosses multiple disciplines by implementing evidence-based strategies to improve safety and outcomes. Previously, we used our institution's electronic health record (EHR) system to assist in improving the quality of care and reducing the cost of heparin-induced thrombocytopenia management, blood product utilization in cardiac surgery and pre-procedure management of coagulopathy in chronic liver disease (Greenberg et al. Blood. Vol. 126, No. 23; Abstract 4467).As a first step, the purpose of this study was to report our healthcare system use of IVCF to: a) define the scope of practice and b) to identify areas for improvement. We propose a practical plan that will assist in improving clinician performance, patient education, and acute and chronic management of IVCF in a large healthcare network based on our recent success utilizing EHR to manage complex medical care.A retrospective review of all IVCF placement performed between July 2014 and December 2015 was conducted. A total of 181 IVCF were placed; 26 (14.4%) permanent IVCF, 143 (79.0%) retrievable IVCF, 12 (6.6%) unknown. Mean age at IVCF placement was 59.34 years (range: 19 - 85); 46.4% were male. Ninety-six (53.0%) patients had active cancer. Surgical Services and Medical Services requested IVCF placements in 112 (61.9%) patients and 69 (38.1%) patients, respectively. Only 13 (7.2%) patients had a SBH consultation prior to IVCF placement.Per SIR guidelines, 60.2% (n=109) of IVCF were placed for absolute indications, 15.5% (n=28) for relative indications, 14.4% (n=26) prophylactically and 9.9% (n=18) with no clear indications.Of the 143 retrievable IVCF, 21 patients died during their hospitalization or were discharged to hospice. Of the remaining 122 cases, documentation of the presence of an IVCF was present in 107 (87.7%) discharge summaries, and outlined instructions for filter retrieval were seen in 19 (15.6%) cases. Only 29 (23.8%) IVCF were retrieved at a mean interval of 159 days (range: 4-511 days). Of the 21 patients that had IVCF placed prophylactically, only 7 (33.3%) IVCF were retrieved.While many of the retrievable filters were placed because of an absolute contraindication (n=64) or relative indication for high-risk of complication to anticoagulation (n=13), 37 (48.1%) patients were discharged on a regimen of anticoagulant therapy.We performed a root cause analysis and identified that a lack of awareness of IVCF evidence-based indications could have played a role in filter use patterns and the lack of a structured system for IVCF tracking in some clinical services resulted in poor IVCF retrieval rates. We propose a practical plan requiring clinicians requesting for IVCF to check an evidence-based indication via EHR. When an IVCF is placed, the Anticoagulation and Bleeding Management Specialty Nurse maintains a log of these patients and provides them with an Information Sheet that lists the date, indication and type of IVCF, specific instructions on IVCF retrieval, and a follow-up appointment in the Benign Hematology clinic for anticoagulant management. The Information Sheet is uploaded onto EHR for documentation. In conclusion, we identified the scope of practice and areas that could be improved by the adoption of a centralized and coordinated approach to monitor patients with IVCF. This study demonstrates the potential impact that a SBH has on health care delivery in both the inpatient and outpatient settings. DisclosuresNo relevant conflicts of interest to declare.

The short-term efficacy of vena cava filters for the prevention of pulmonary embolism in patients with venous thromboembolism receiving anticoagulation: Meta-analysis of randomized controlled trials.

Objectives To perform a meta-analysis of randomized controlled trials assessing the effectiveness of inferior vena cava filters in patients with deep vein thrombosis for preventing pulmonary embolism. Method Relevant randomized controlled trials of inferior vena cava filters for the prevention of pulmonary embolism were identified by searching electronic databases updated in February 2016. Relative risks of recurrent pulmonary embolism, recurrent deep vein thrombosis, and mortality at three months were analyzed. Results Three published randomized controlled trials were included involving a total of 863 deep vein thrombosis patients. No significant differences were detected with inferior vena cava filters placement with regard to the incidence of recurrent pulmonary embolism or fatal pulmonary embolism. There were also no significant differences in the incidence of recurrent deep vein thrombosis or mortality with inferior vena cava filters placement at three months. Conclusions Inferior vena cava filter in addition to anticoagulation was not associated with a reduction in the incidence of recurrent pulmonary embolism as compared with anticoagulation alone in patients with deep vein thrombosis in the short term.

Temporary and Permanent Inferior Vena Cava Filters in the Oncology Population

BackgroundThe use of both temporary and permanent inferior vena cava (IVC) filters continues to rise yet randomized data regarding efficacy and complication rates are limited, especially in cancer patients. Temporary IVC filters are associated with higher costs and can have more long-term complications than permanent IVC filters. In this study, we examined the use of temporary and permanent IVC filters in the cancer population, a group at high risk for venous thromboembolism (VTE) as well as complications of anticoagulation.MethodsThis single-institution study included patients with active malignancy receiving adjuvant chemotherapy or considered for future chemotherapy that received an interventional radiology (IR) placed temporary (N=179) or permanent (N=207) IVC filter from 2009 to 2013. Patients were followed prospectively from the time of filter placement. The database included patient demographics, type of malignancy, indication for filter placement, time to filter retrieval, complications of placement/retrieval, rates of VTE recurrence and cause of death (if applicable).ResultsPatient demographic information is shown in Table 1. The most common reasons cited for filter placement included a contraindication to anticoagulation from bleeding (36%), recent or upcoming procedure (19%), thrombocytopenia (17%), and surgical prophylaxis (8%). 21% of filters were placed in patients with no contraindication to anticoagulation or failure of anticoagulation. Of these, 35% of the temporary filters were not removed. IVC filters were most frequently placed in patients with underlying hematologic malignancies (22%), gastrointestinal malignancies (22%) and lung cancer (16%). The majority of patients had stage III or IV cancer (62%).Of the 179 temporary filters placed, 60% were not retrieved. The most common reasons for failure of filter retrieval included: progressive disease/clinical deterioration (51%), continued contraindication to anticoagulation (23%) and loss of follow-up (8%). Only 2% of filters could not be removed because of mechanical reasons. Of the 81 attempted filter removals, 5 had in-filter thrombus, 4 had surrounding fibrin sheaths, 4 had filter tilt, 1 had IVC in-growth, 1 had broken struts and 1 had a procedure-related infection.The rate of recurrent VTE in all patients studied was 23% (21% in temporary filter group, 24% in permanent filter group), including 20 pulmonary emboli (PE) and 14 thromboses within the IVC filter. The majority of recurrences occurred off of anticoagulation (58%). Only 34% could be maintained on therapeutic anticoagulation. By study end, 72% of patients had died, most commonly due to progressive cancer. Median time from filter placement to death was 2.9 months (range: 0.1-64.7 months). Seventy-five patients (19%) died within 30 days of filter placement. They were more likely to have stage IV disease (78% vs. 54%). Of these 75 patients, three experienced recurrent VTE, two with lower extremity DVTs and one with an IVC thrombus. Data on filter costs were also collected. Costs were attributable to the placement and retrieval procedures when applicable ($10,983.00 and $8,824.00, respectively) as well as the device itself ($1,576.00).ConclusionsMalignancy-associated thrombosis is common and associated with a high rate of recurrence. While most recurrent VTE after IVC filter placement were deep vein thromboses, a relatively large number of PE's occurred after filter placement as well. A significant number of patients with malignancy-associated thrombosis who underwent IVC filter placement had no contraindication to anticoagulation or recurrent VTE while on anticoagulation. Better prospective studies are needed to assess the safety and efficacy of IVC filters in the setting of hemodynamic compromise, extensive clot burden or for surgical prophylaxis, especially in the oncology population. In this cohort, the majority of filters were placed in patients with advanced cancer with likely short life expectancies, suggesting the patient selection for filter placement could be optimized. Finally, the cost of filter placement and retrieval is substantial, further emphasizing the need for better prospective data to identify the subset of patients who will derive the most benefit from filter use. [Display omitted] DisclosuresStein:Incyte Corporation: Membership on an entity's Board of Directors or advisory committees, Research Funding. Lewandowski:Cook Medical: Consultancy; Boston Scientific: Membership on an entity's Board of Directors or advisory committees.

Risk of Venous Thromboembolism in Multiple Myeloma: Identification of Risk Factor

BackgroundCompared to the general population, patients with multiple myeloma (MM) have a 9-fold increased risk of developing venous thromboembolism (VTE). VTE is a preventable disease that causes death and morbidity. Thromboprophylaxis is a safe and effective way to decrease VTE in other high-risk populations (i.e. atrial fibrillation). Current guidelines recommend pharmacologic thromboprophylaxis in patients with MM receiving an immunomodulatory agent in the presence of additional VTE risk factors. However, putative risk factors vary across guidelines and lack validation. Recently, an attempt to validate the International Myeloma Working Group 2014 guidelines for thromboprophylaxis found current risk factors to be inadequate. Identification of risk factors for VTE in MM can allow for effective risk-stratification to clarify thromboprophylaxis in the MM population. We sought to identify risk factors for VTE in patients with MM.MethodsWe identified patients diagnosed with MM within the Veterans Administration Central Cancer Registry from September 1, 1999 and December 31, 2013 and followed them through October 2014. We excluded patients who did not receive MM-directed therapy within 6 months of diagnosis. Using a previously validated algorithm, (Thromb Res, 2015), we identified patients diagnosed with VTE after MM diagnosis by a combination of ICD-9 code for VTE plus pharmacologic treatment for VTE or IVC filter placement. We obtained information on baseline patient demographics, medical comorbidities, laboratory data, MM-directed therapy, and use of aspirin and/or warfarin. Univariate analyses identified the association between individual variables and VTE in the cohort. Clinically meaningful and significant associations were included in the multivariate model. Multivariate analysis was done using competing risks regression modeling. The study was approved by the Saint Louis VHA Medical Center and Washington University institutional review boards.ResultsA total of 3,384 patients comprised the final cohort of whom 414 developed a VTE. Patients who developed VTE were more likely to be younger (66.2 vs 68.5, p < .001), have a body mass index (BMI) ≥ 25 (p < .001), be diagnosed with MM prior to 2007 (p < .001), have a VTE before MM diagnosis (p < .001), have a lower comorbidities (p < .001), have received autologous stem cell transplant (ASCT) (p < .001), have received lenalidomide, thalidomide, or bortezomib (p < .001), and less likely to have received warfarin (p < .001). Among predefined risk factors, age (Hazard Ratio (HR) 0.99, 95% Confidence Interval (CI) 0.98-1.00, p = 0.02), VTE before MM diagnosis (HR 4.13, 95% CI 2.81-6.05, p < .001), heart failure (HR 0.70, 95% CI 0.51-0.96, p = 0.03), treatment with thalidomide (HR 2.02, 95% CI 1.63-2.50, p < 0.001), BMI ≥ 30 (HR 1.34, 95% CI 1.03-1.74, p = 0.03), and diabetes mellitus (HR 0.79, 95% CI 0.63-0.99, p = 0.04) were associated with VTE. After inclusion into multivariate analysis and adjusting for warfarin/aspirin use; age, BMI, year of MM diagnosis, VTE before MM, thalidomide, warfarin, and aspirin were all associated with VTE in MM (Table 1).ConclusionWe identified several risk factors associated with VTE in MM. Incorporation of these risk factors into a MM-specific risk model has the potential to reduce risk of VTE in MM. [Display omitted] DisclosuresSanfilippo:National Heart, Lung, and Blood Institute: Research Funding. Gage:National Heart, Lung, and Blood Institute: Research Funding. Carson:American Cancer Society: Research Funding.

Application of a Validated Predictive Model for Venous Thromboembolism in Cancer to Patients with Multiple Myeloma

BackgroundPatients with multiple myeloma (MM) have a 9-fold increased risk of developing venous thromboembolism (VTE). Current guidelines recommend pharmacologic thromboprophylaxis in patients with MM receiving an immunomodulatory agent in the presence of additional VTE risk factors (NCCN 2015, ASCO 2014, ACCP 2012). However, putative risk factors vary across guidelines and no validated VTE risk tool exists for MM. Khorana et al. developed a VTE risk score in patients with solid organ malignancies and lymphoma (Blood, 2008). We sought to apply the Khorana et al. score in a population with MM.MethodsWe identified patients diagnosed with MM within the Veterans Health Administration (VHA) between September 1, 1999 and December 31, 2009 using the International Classification of Diseases (ICD)-03 code 9732/3. We followed the cohort through October 2014. To eliminate patients with monoclonal gammopathy of undetermined significance and smoldering myeloma, we excluded patients who did not receive MM-directed therapy within 6 months of diagnosis. We also excluded patients who did not have data for hemoglobin (HGB), platelet (PLT) count, white blood count (WBC), height and weight, as these are all variables included in the Khorana et al. risk model. Height and weight were assessed within one month of diagnosis and used to calculate body mass index (BMI). We measured HGB, PLT count, and WBC count prior to treatment initiation: within two months of MM diagnosis. A previously validated algorithm, using a combination of ICD-9 code for VTE plus pharmacologic treatment for VTE or IVC filter placement, identified patients with incident VTE after MM diagnosis (Thromb Res, 2015). The study was approved by the Saint Louis VHA Medical Center and Washington University School of Medicine institutional review boards.We calculated VTE risk using the Khorana et al. score: We assigned 1 point each for: PLT ≥ 350,000/μl, HGB < 10 g/dl, WBC > 11,000/μl, and BMI ≥ 35 kg/m2. Patients with 0 points were at low-risk, 1-2 points were considered intermediate-risk and ≥3 points were termed high-risk for VTE.We assessed the relationship between risk-group and development of VTE using logistic regression at 3- and 6-months. We tested model discrimination using the area under the receiver operating characteristic curve (concordance statistic, c) with a c-statistic range of 0.5 (no discriminative ability) to 1.0 (perfect discriminative ability).ResultsWe identified 1,520 patients with MM: 16 were high-risk, 802 intermediate-risk, and 702 low-risk for VTE using the scoring system in the Khorana et al. score. At 3-months of follow-up, a total of 76 patients developed VTE: 27 in the low-risk group, 48 in the intermediate-risk group, and 1 in the high-risk group. At 6-months of follow-up there were 103 incident VTEs: 41 in the low-risk group, 61 in the intermediate-risk group, and 1 in the high-risk group. There was no significant difference between risk of VTE in the high- or intermediate-risk groups versus the low-risk group (Table 1). The c-statistic was 0.56 at 3-months and 0.53 at 6-months (Figure 1).ConclusionPreviously, the Khorana score was developed and validated to predict VTE in patients with solid tumors. It was not a strong predictor of VTE risk in MM. There is a need for development of a risk prediction model in patients with MM. [Display omitted] [Display omitted] DisclosuresCarson:American Cancer Society: Research Funding. Gage:National Heart, Lung and Blood Institute: Research Funding. Kuderer:Janssen Scientific Affairs, LLC: Consultancy, Honoraria. Sanfilippo:National Heart, Lung and Blood Institute: Research Funding.

Inferior vena cava filter retrievals, standard and novel techniques.

The placement of an inferior vena cava (IVC) filter is a well-established management strategy for patients with venous thromboembolism (VTE) disease in whom anticoagulant therapy is either contraindicated or has failed. IVC filters may also be placed for VTE prophylaxis in certain circumstances. There has been a tremendous growth in placement of retrievable IVC filters in the past decade yet the majority of the devices are not removed. Unretrieved IVC filters have several well-known complications that increase in frequency as the filter dwell time increases. These complications include caval wall penetration, filter fracture or migration, caval thrombosis and an increased risk for lower extremity deep vein thrombosis (DVT). Difficulty is sometimes encountered when attempting to retrieve indwelling filters, mainly because of either abnormal filter positioning or endothelization of filter components that are in contact with the IVC wall, thereby causing the filter to become embedded. The length of time that a filter remains indwelling also impacts the retrieval rate, as increased dwell times are associated with more difficult retrievals. Several techniques for difficult retrievals have been described in the medical literature. These techniques range from modifications of standard retrieval techniques to much more complex interventions. Complications related to complex retrievals are more common than those associated with standard retrieval techniques. The risks of complex filter retrievals should be compared with those of life-long anticoagulation associated with an unretrieved filter, and should be individualized. This article summarizes current techniques for IVC filter retrieval from a clinical point of view, with an emphasis on advanced retrieval techniques.

Complications of inferior vena cava filters.

Inferior vena cava (IVC) filter placement is a relatively low risk alternative for prophylaxis against pulmonary embolism in patients with pelvic or lower extremity deep venous thrombosis who are not suitable for anticoagulation. There is an increasing trend in the number of IVC filter implantation procedures performed every year. There are many device types in the market and in the early 2000s, the introduction of retrievable filters brought an additional subset of complications to consider. Modern filter designs have led to decreased morbidity and mortality, however, a thorough understanding of the limitations and complications of IVC filters is necessary to weight the risks and benefits of placing IVC filters. In this review, the complications associated with IVC filters are divided into procedure related, post-procedure, and retrieval complications. Differences amongst the device types and retrievable filters are described, though this is limited by a significant lack of prospective studies. Additionally, the clinical presentation as well as prevention and treatment strategies are outlined with each complication type.

Venous Thrombotic, Thromboembolic, and Mechanical Complications After Retrievable Inferior Vena Cava Filters for Major Trauma

Background The ideal thromboprophylaxis in patients at risk of bleeding is uncertain. This retrospective cohort study assessed the risk factors for complications after using retrievable inferior vena cava (IVC) filters for primary or secondary thromboembolism prophylaxis in patients after major trauma. Methods Using data from radiology, trauma and death registries, the incidence of and risk factors for subsequent deep venous thrombosis (DVT), venous thromboembolism (VTE), and mechanical complications related to retrievable IVC filters in patients, admitted between 2007 and 2012, were assessed in a single trauma centre. Results Of the 2940 major trauma patients admitted during the study period, a retrievable IVC filter was used in 223 patients (7.6%). Thirty-six patients (16%) developed DVT or VTE subsequent to placement of IVC filters (median 20 days, interquartile range 9-33), including 27 with lower limb (DVT), 8 upper limb DVT, and 4 pulmonary embolism. A high Injury Severity Score, tibial/fibular fractures, and a delay in initiating pharmacological thromboprophylaxis after insertion of the filters (14 vs 7 days, P=0.001) were significant risk factors. Thirty patients were lost to follow-up (13%) and their filters were not retrieved. Mechanical complications - including filters adherent to the wall of IVC (4.9%), IVC thrombus (4.0%), and displaced or tilted filters (2.2%) - were common when the filters were left in situ for >50 days. Conclusions A delay in initiating pharmacological thromboprophylaxis or filter removal were associated with an increased risk of subsequent DVT, VTE, and mechanical complications of retrievable IVC filters in patients after major trauma.

Are too many inferior vena cava filters used? Controversial evidences in different clinical settings: a narrative review.

The use of inferior vena cava filters to prevent pulmonary embolism is increasing mainly because of indications that appear to be unclearly codified and recommended. The evidence supporting this approach is often heterogeneous, and mainly based on observational studies and consensus opinions, while the insertion of an IVC filter exposes patients to the risk of complications and increases health care costs. Thus, several proposed indications for an IVC filter placement remain controversial. We attempt to review the proof on the efficacy and safety of IVC filters in several "special" clinical settings, and assess the robustness of the available evidence for any specific indication to place an IVC filter.

Common iliac vein thrombosis as a result of proximal venous stenosis following renal transplantation: A case report

Proximal iliac vein stenosis resulting in iliac vein thrombus and venous outflow obstruction in renal transplant patients is an exceedingly rare occurrence. We present a case of a 63-year-old male who underwent deceased donor renal transplantation and presented 12 days later with ipsilateral lower extremity swelling and plateauing serum creatinine. Further work-up demonstrated proximal iliac vein deep venous thrombosis and anticoagulation was initiated. However, propagation of the thrombus developed despite receiving therapeutic anticoagulation. Subsequent venography demonstrated proximal iliac venous stenosis and the patient underwent successful catheter-directed alteplase thrombolysis, inferior vena cava filter placement and iliac vein stenting with salvage of the renal allograft. A diagnostic strategy and management algorithm for iliac vein stenosis and thrombosis in a renal transplant recipient is proposed.

Bundling of Reimbursement for Inferior Vena Cava Filter Placement Resulted in Significantly Decreased Utilization between 2012 and 2014

On January 1, 2012, reimbursement for inferior vena cava filters (IVCFs) became bundled by the Centers for Medicare and Medicaid Services. This resulted in ICVF placement (CPT code 37191) now yielding 4.71 relative value units (RVUs), a decrease from 15.6 RVUs for placement and associated procedures (CPT codes 37620, 36010, 75825-26, 75940-26). Our hypothesis was that IVCF utilization would decrease in response to this change as other procedures had done once they had become bundled. Including data from 2010 to 2011 (before bundling) and 2012 to 2014 (after bundling), we utilized 5% inpatient, outpatient, and carrier files of Medicare limited data sets and analyzed IVCF utilization before and after bundling across specialty types, controlling for total diagnosis of deep vein thrombosis (DVT) and pulmonary embolism (PE) (ICD-9 codes 453.xx and 415.xx, respectively) and placement location. In 2010 and 2011, the rates/10,000 DVT/PE diagnoses were 918 and 1,052, respectively (average 985). In 2012, 2013, and 2014, rates were 987, 877, and 605, respectively (average 823). Comparing each year individually, there is a significant difference (P<0.0001) with 2012, 2013, and 2014 having lower rates of ICVF utilization. Comparing averages in the 2010-2011 and 2012-2014 groups, there is also a significant decrease in utilization after bundling (P<0.0001). Following the bundling of reimbursement for IVCF placement, procedural utilization decreased significantly. More data from subsequent years will be needed to show if this decrease utilization continues to persist.

Impact of Parkinson’s disease on perioperative complications and hospital cost in multilevel spine fusion: A population-based analysis

Parkinson’s disease (PD) is a neurodegenerative disorder manifesting over time to result in reduced mobility. The impact of PD on spinal fusion has yet to be addressed on a nationwide level. The Nationwide Inpatient Sample (NIS) from 2001 to 2012 was used for analysis. Admissions with spinal fusion of two or more vertebrae (ICD-9 codes=81.62, 81.63 and 81.64) were included and then stratified based on the presence or absence of PD (ICD-9 code=332.0); patients with cancer (ICD-9 codes=140–239) or trauma (ICD-9 codes=805.0–806.9) were excluded. Propensity score matching adjusted for potential confounding effects introduced by patient age, race, sex, and primary payer for care. 570,858 patients receiving spinal fusion of two or three vertebrae (1–2 levels) were identified, 2648 (0.5%) of whom had PD. Analysis revealed that PD was independently predictive for increased in-hospital mortality, durotomy, paraplegia, postoperative infection, venous thrombotic events, inferior vena cava filter placement, red blood cell transfusion, pulmonary embolism, total hospital charge >$200,000, length of stay >1week, non-routine discharge disposition, acute respiratory distress syndrome, acute posthemorrhagic anemia, multisystem complications (nervous system, cardiac, respiratory, urinary), and device-related complications (all P<0.001). In conclusion, these findings from a nationwide analysis comprising a 12-year period indicate that PD is significantly associated with increased in-hospital morbidity, mortality, and cost following spine fusion of 1–2 levels when compared with the general population. These findings point to the need for risk stratification and adjustment of quality metrics for this growing patient population, and should be integrated into operative decision-making and patient counseling.

Outcomes of Stent Placement for Chronic Occlusion of a Filter-bearing Inferior Vena Cava in Patients with Severe Post-thrombotic Syndrome

To evaluate the technical aspects and short-term clinical results of stent placement for chronic occlusion of a filter-bearing inferior vena cava (IVC) in patients with severe post-thrombotic syndrome (PTS). A retrospective analysis of 24 patients with severe PTS associated with occlusion of a filter-bearing IVC treated by stent placement was conducted at a single institution from January 2010 to December 2014. Patient-reported quality of life and limb Villalta scores were evaluated before and after treatment by questionnaire and clinical examination, respectively. Stent patency was evaluated by duplex Doppler ultrasound, venography, or venous computed tomographic (CT) angiography. All patients tolerated the procedure well. Nineteen patients with filter-bearing IVC and bilateral iliofemoral occlusions were treated with "double-barrel" stents, two were treated with fenestrated stents, and the remaining three patients were treated by unilateral stent placement of the iliofemoral vein and filter-bearing IVC. Quality of life and Villalta scores were significantly improved (p<.001) after the procedure. The 1-year, and 2-year cumulative primary and secondary stent patency rates were 67% and 91%, and 45% and 77%, respectively. During a median follow-up period of 27 months (range 3-55 months), the cumulative rates of complete relief of pain (visual analog scale >5) and swelling (grade 3) were 77% (13 of 17 limbs at risk) and 75% (24 of 32 limbs at risk), respectively. There were 23 limbs with active ulcers and the cumulative rate of ulcer healing at 2 years was 73%. There were no cases of clinical bleeding, symptomatic pulmonary embolism, or mortality. Recanalization of an occluded IVC filter and stent placement through the filter is a feasible and safe method for management of PTS associated with filter-bearing IVC occlusions, with acceptable short-term stent patency and clinical results. However, close follow-up after procedure is necessary because of a relatively high re-occlusion rate.

Updates on Advanced Therapies for Acute Pulmonary Embolism

Venous thromboembolism is the third common vascular disease after acute myocardial infarction and stroke, and acute pulmonary embolism (PE) remains as the most common preventable cause of in-hospital mortality. In addition to routine anticoagulant therapy, several advanced treatment options have been introduced over the past three decades. We provide a succinct and contemporary summary of the evidence base and important indications for inferior vena caval filter placement, systemic and catheter-based thrombolytic therapy, as well as percutaneous and surgical thrombectomy. Appropriate case selection for advance therapies for PE could minimize the adverse effects and costs, while optimizing the outcomes.

IVC Filter Perforation: A Rare Cause of Abdominal Pain

Abdominal pain is one of the most common complaints of patients seeking medical care. Devices such as inferior vena cava (IVC) filters are frequently placed in patients with deep vein thrombosis and contraindications to anticoagulation. Symptomatic perforation of the filter into the adjacent tissue or vessels is a rare, but challenging, complication. A 65-year-old woman with a history of asthma and anxiety presented to clinic with abdominal pain. Seven weeks prior, she had been hospitalized for a diverticular bleed and focal diverticulitis. During her stay, venous sonography demonstrated a right femoral vein thrombosis and anticoagulation was initiated with heparin. She developed significant rectal bleeding leading to anticoagulation discontinuation and placement of a retrievable IVC filter. On presentation to the clinic, she reported lower back pain radiating to the right flank and buttock, nausea, and cramping post prandial abdominal pain. She had previously presented to a local emergency department with these symptoms and was prescribed an anti-spasmodic agent after clinical and laboratory evaluation was unrevealing. Now, seven weeks later, she reported persistence of symptoms. On evaluation, she was afebrile, hemodynamically stable, and physical examination was without abnormalities. CT scan of the abdomen and pelvis revealed caudal migration of the IVC filter with the primary legs perforating the IVC and splaying into the L3/L4 intervertebral disc space and aorta (Figures 1,2). She was admitted for endovascular retrieval of the IVC filter. A post-retrieval vena cavagram and CT angiogram with 3D vessel reconstruction demonstrated no complications such as peri-caval hematoma. Her symptoms resolved and she was discharged home the following day. Perforation of the IVC by a primary leg of the device is a rare, but important complication. Symptomatic perforation usually presents in the days to weeks following placement; however, symptoms may not manifest for years later. It is wise to have a high index of suspicion in patients with recent filter placement with only vague abdominal complaints that cannot be otherwise explained. Retrievable filters should be removed as soon as they are no longer needed. We recommend prompt removal of the device via endovascular or surgical approach for symptomatic perforations and asymptomatic perforations involving vital tissues such as the aorta, small bowel, and bone.Figure 1Figure 2

An Uncommon Cause of Abdominal Pain and Gastrointestinal Hemorrhage from Duodenal Perforation by an Inferior Vena Cava Filter

A 92-year-old female with a past medical history of pulmonary embolism on Coumadin status post retrievable inferior vena cava (IVC) filter placement in 2011 presented with hematochezia and abdominal pain. On arrival to the emergency department, the patient's hemoglobin was 6.4 G/DL (baseline of 11 G/DL) and INR of 3.8. Vital signs were intially stable on presentation and the patient developed hypotension with systolic blood pressure in the 90s. The patient was resuscitated with transfusion of packed red blood cells, platelets and plasma. Vitamin K was given for reversal of her coagulopathy. A technetium-99m red blood cell scintigraphy (bleeding scan) for evaluation of gastrointestinal hemorrhage was obtained that identified an area of active bleeding in the region of the small bowel. Following the positive scan, the patient subsequently underwent conventional angiography on two occasions; however, no therapeutic intervention could be performed, as the bleeding source could not be identified. CT angiography was obtained for ongoing abdominal pain and bleeding that demonstrated the infrarenal IVC filter struts extended beyond the lumen of the IVC, suspicious for perforation through the IVC wall. One strut of the IVC filter appeared to extend through the medial wall of the 2nd portion of the duodenum and into the duodenal lumen. We believe an open surgical approach for filter retrieval would have been the most effective intervention, however, given patient's advanced age, critical condition, and multiple co-morbidities the patient was enrolled in hospice care and eventually expired. In review of literature, overall IVC filter perforation incidence is reported at 0.2% and should be considered in patients with abdominal pain and evidence of bleeding. Intervention with surgical retrieval is reported to be successful in well-selected patients.Figure 1Figure 2Figure 3