Inferior Vena Cava Filter Placement Research Articles

Abstract No. 577 Variation of practice in the management of anticoagulation in low bleeding risk interventional radiology procedures

To determine the variability in practice of anticoagulant management for low-risk procedures in order to improve the quality of guidance provided to interventionalists. Academic, private, and mixed practice interventional radiologists with varying levels of experience were surveyed on pre-procedural antiplatelet and anticoagulation management for 12 low bleeding risk procedures as defined by the SIR Standards of Practice Committee (1). Participants were asked to select the medications they would stop for a given procedure. No additional information was given. The survey was distributed on SIR Connect and Twitter. 45 interventional radiologists responded to the survey. Approximately 56% of the respondents were in private practice, 24% academia, and 20% mixed practice. Approximately 56% were attending physicians with over 10 years of experience, 27% with 5-10 years, and 17% with less than 5 years. One resident responded. Rates of stopping anticoagulation were defined as almost none (<10%), few (10-40%), about half (40-60%), most (60-90%), and almost all (>90%). For nearly all procedures, responses varied. For example, few respondents stopped antiplatelet medications, but about half stopped anticoagulants prior to paracentesis. For tunneled central venous access, about half of respondents stopped antiplatelets, but most stopped anticoagulants. For both IVC filter placement and removal, almost none stopped antiplatelet medication, and few stopped anticoagulants. When biopsying a superficial mass, few respondents stopped antiplatelet medication, and about half stopped anticoagulants. The SIR Standards of Practice Committee consensus guidelines, written by Patel et al, provide recommendations for managing coagulation status (1). Despite this, real-world pre-procedural management of antiplatelet and anticoagulant medications remains varied, particularly for low bleeding risk procedures. This variability suggests that each interventional radiologist manages anticoagulation for these procedures based on his or her own experience and circumstance rather than strict adherence to any one set of guidelines.

Statin therapy associated with improved thrombus resolution in patients with deep vein thrombosis

ObjectiveStatin therapy has been associated with a decreased incidence of venous thromboembolism (VTE) in clinical trials and enhanced thrombus resolution in animal models. The effect of statins on thrombus resolution has not been reported clinically. This study investigates the association of statins with thrombus resolution or improvement in patients with deep venous thrombosis (DVT). MethodsA retrospective study of the electronic medical records of consecutive adult patients presenting with lower extremity DVT was performed. Patients were divided into two groups based on statin therapy (statin group) or lack thereof (nonstatin group). The two groups were compared with respect to demographics, comorbidities, and risk factors for VTE. Initial as well as all subsequent ultrasound reports were reviewed for each patient to determine extent of DVT and subsequent change in thrombus characteristics. Long-term outcomes examined were mortality, VTE recurrence, and thrombus improvement or resolution on follow-up ultrasound examination. Multivariable analysis was used to determine independent predictors of thrombus resolution or improvement, VTE recurrence, and mortality. ResultsA total of 818 patients with DVT were identified (statin group, n = 279 [34%]; nonstatin group, n = 539 [66%]). The patients in the statin group were significantly older (P < .001). Patients on statins were more likely to have risk factors for and manifestations of atherosclerosis and to be on antiplatelet therapy (P < .001), whereas those in the nonstatin group were more likely to have a hypercoagulable disorder (P = .009) or prior DVT (P = .033). There was no significant difference in provoked DVT, extent of DVT, or association with pulmonary embolism (PE), but patients on statins were more likely to have high-risk PE (P = .046). There was no difference in patients receiving anticoagulation, type and duration of anticoagulation, inferior vena cava filter placement, or treatment with lytic therapy. There was no difference in thrombus resolution, mortality, or recurrence of DVT, PE, or VTE between the groups. On multivariable analysis, age, proximal DVT, CAD, and cancer were associated with higher mortality, whereas anticoagulation with coumadin and direct oral anticoagulants and antiplatelet therapy were associated with lower mortality. Statin therapy, antiplatelet therapy, and younger age were associated with thrombus resolution or improvement. ConclusionsStatin therapy is associated with greater thrombus resolution or improvement in patients with DVT. However, statin therapy in this study was not associated with different clinical outcomes of VTE recurrence or mortality.

Retrievable Inferior Vena Cava Filters: A Tertiary Centre Perspective and Quality Assurance Study

PurposeTo conduct a retrospective review and quality assurance study of inferior vena cava (IVC) filter retrieval over a two-year period at a tertiary care centre. MethodsPatients who underwent IVC filter placement or retrieval over a two-year period were identified. Medical records were reviewed for patient characteristics, filter indication, time to filter retrieval, and complications. ResultsIVC filters were placed in 229 patients between January 1, 2015 and December 31, 2016. 113 retrievals were attempted and 101 filters were successfully retrieved (89.4%). Median time to first retrieval attempt was 48 days (range of 5–728). Seventy-one patients died in the interval after filter insertion before a retrieval attempt at a median time of 27 days (range of 3–430). In 17 patients, retrieval was complicated by or delayed because of penetration of IVC wall (n = 6), large thrombus burden trapped by filter (n = 5), filter tilt or migration (n = 3), and unclear reasons (n = 3). Time-to-first unsuccessful retrieval attempt was 141 days (median). Of all filters placed, 55.9% were never retrieved. Excluding deceased patients with in-situ filters (n = 71) and unsuccessful retrievals left in-situ as permanent filters (n = 5), there remains 52 patients (33%), with a median filter in-situ time of 488 days. ConclusionOur study indicates that as many as 33% of patients may have been lost to follow-up of their in-situ IVC filter. Considering widespread reports of long-term complications and the recent safety alert issued by Health Canada, it is evident that a unified strategy is needed to track patients post filter insertion.

Outcomes of IVC Filter Use in Heparin-Induced Thrombocytopenia: A Retrospective Study

Introduction Heparin-induced thrombocytopenia (HIT) is a prothrombotic state characterized by prior exposure to heparin products and decreased platelets. Inferior vena cava filters (IVCFs) are often placed in patients with deep venous thrombus (DVT) or pulmonary emboli (PE) that are not candidates for anticoagulation. Patients with HIT are in a hypercoagulable state and presumably may have high rates of thrombotic events after IVCF placement. Recommendations against insertion of an IVCF in patients with acute HIT or acute isolated HIT have been supported by a single, small case series (n=10) and a few case reports of IVC-related thrombotic events in patients with IVCF placement either before or during time of HIT diagnosis.1 However, there have not been any larger studies looking specifically at patients with HIT and IVCF placement and subsequent outcomes.Methods We retrospectively reviewed patient charts from the Kaiser Permanente Northern California electronic medical record database (over 4 million patients) from 2006-2015 and cross-referenced patients with both an ICD-9 code for IVCF placement and for HIT. Chart review was done on the patients who met both criteria. The patients were divided into two subgroups- those with HIT diagnosis confirmed (SRA positive or HIT ab >1) and those with HIT diagnosis likely (HIT ab <1), as well as sub-groups based on the timing of IVCF placement relative to HIT diagnosis (within 14 days or not). Sub-groups were analyzed for thrombotic events after placement of IVCF, including new or extension of DVT, new or extension of PE, IVC thrombosis, lower extremity phlegmasia cerulea dolens, critical limb ischemia, and mortality.Results During this ten-year period, 3,934 patients had IVCFs placed and 814 patients were identified with HIT diagnostic codes, with 30 patients meeting criteria for both an ICD-9 code for HIT and IVCF placement. Of these 30 patients, 4 were excluded as they had IVCF placement well after diagnosis of HIT (>14 days). Of these patients (n=26), a total of 4 patients (15.4%) had thrombotic progression/complications, either a single complication or multiple complications. Overall, 11.5% (n=3) had progression of DVT noted either on ultrasound or clinically, 3.9% (n=1) had IVC thrombosis, and 3.9% (n=1) had lower extremity phlegmasia. Of these 26 patients, we further examined those who had an IVCF placed up to 14 days before or after HIT diagnosis (n=17). Of these patients, 11.8% (n=2) had progression of DVT, 5.9% (n=1) had IVC thrombosis, and no patients had lower extremity phlegmasia. There were 2 deaths (7.7%) related to thrombotic events. Six-month all-cause mortality was 23% (n=7) with similar mortality rates in patients who had HIT confirmed vs. HIT likely. Patients who had an IVCF placed within 30 days of HIT diagnosis (27% mortality) and after 30 days of HIT diagnosis (25% mortality) did not have significant difference in six-month all-cause mortality. Our data tracked mortality up to 12 months (27%).Conclusion Our study found a thrombotic rate of 15.4% in HIT patients with IVCF placement, while a rate of thrombosis after IVCF placement in patients without HIT has been reported between 2-30%.2 The rate of new thrombotic events in HIT alone is reported to be 23-35%.3 Our six-month all-cause mortality rate was 26.9%, with mortality directly related to thrombotic events at 7.7%. Six-month mortality associated with HIT without IVCF placement has been reported at 20-30%.4 One patient developed lower extremity phlegmasia, which is reported to be rare in the literature. Our results do not show an increased risk of mortality, DVT, PE, IVC thrombosis, or lower extremity phlegmasia in the setting of IVCF placement in patients diagnosed with HIT, as compared to rates of complications in patients with only HIT or in patients with only IVCF placement. While HIT is associated with an increased risk of thrombosis, and a published small case series (n=10) recommended against placing IVCFs in these patients, our larger, retrospective study does not demonstrate increased thrombotic events in this patient population beyond patients with only HIT or only IVCFs.Full references available upon request1. Jung, 20112. Milovanovic, 20153. Bruce, 20034. Benjamin, 2016 DisclosuresNo relevant conflicts of interest to declare.

Impact of Venous Thromboembolism during High Intensity Chemotherapy for Acute Leukemia Patients on Duration of Hospital Stay

Background: Patients (pts) with hematologic malignancies have an increased risk of venous thromboembolism (VTE) events, driven by both the underlying cancer and cancer treatment. This risk exists even in acute leukemia (AL) in the setting of profound thrombocytopenia and coagulopathies, which can delay VTE diagnosis and complicate management. We evaluated the incidence of VTE in AL pts during an admission for chemotherapy and determined its effect on the duration of hospital stay and likelihood of intensive care unit (ICU) admission.Methods: All pts admitted to the Cleveland Clinic inpatient leukemia service with a diagnosis of acute myeloid (AML), lymphoblastic (ALL), or promyelocytic leukemia (APL) between January 1, 2013 and March 31, 2018 and treated with high-intensity chemotherapy were included. High intensity regimens for AML and APL included infusional cytarabine and an anthracycline with the addition of ATRA for latter and for ALL included Hyper-CVAD and CALBG regimens. Pts were excluded if they were admitted directly to the ICU or were transferred after initiating chemotherapy from another institution. Cases with VTE were defined using specific ICD-9-CM codes [451.1x, 451.2; 451.81, 453.1, 453.2, 453.8, 453.9, 415.1x; and, in addition, 997.2 or 997.3 when coupled with a secondary diagnosis of VTE]. All VTE cases identified through this strategy via an electronic medical record query were additionally validated on subsequent chart review. Pts with a diagnosis of VTE were matched 1:3 based on age, sex, race, and leukemia subtype to pts who did not experience VTE during the incident admission. Pts were also assessed for administration of prothrombotic agents, including: PEG-asparaginase, oral contraceptives, and tyrosine kinase inhibitors. The length of stay for the incident hospitalization and incidence of ICU admission were compared between pts who did and who did not experience VTE.Results: Of the 400 AL pts admitted to the inpatient leukemia service during the study period to receive high-intensity chemotherapy, 10 (2.5%) had a documented VTE during the admission. Baseline characteristics of the 1:3 matched cohorts (AL with and without VTE) are shown in Table 3. The median age of the AL pts who developed VTE was 54.5 years (range, 20-78 yrs), 60% were females, median platelet count at the time of VTE diagnosis was 117,900/mL [(range, 29-476,000/mL); 4 pts had platelet (plt) counts below 50,000/mL, 8 pts had plt below 100,000/mL; 2 pts had normal plt counts], and four pts had bloodstream infections within 7 days of VTE occurrence. By disease breakdown, four had AML, 3 had APL and 3 had ALL. By treatment course, 9 pts were receiving initial chemotherapy 1 pt was receiving salvage therapy. By VTE site, 8 patients had line associated VTE and 2 patients had pulmonary embolism. Five VTE pts were treated with either unfractionated or low molecular weight heparin, 2 underwent IVC filter placement and 3 were untreated.Pts in the VTE group experienced a longer duration of hospitalization compared to those who did not have a VTE event (29.81 vs 23.13 days, respectively, P=.027), and were more likely to be admitted to the ICU compared to those who did not experience VTE (66.7% vs 14.8%, respectively, P=.010). VTE risk was not associated with use of prothrombotic agents (p=.430).Summary and Conclusion: While the incidence of VTE in our patient population was lower than what has been previously reported, it was associated with a prolonged hospitalization and increased risk of ICU admission. The incidence of VTE was not associated with use of thrombotic agents and VTE events occurred in patients with normal plt counts and even in the setting of moderate or severe thrombocytopenia. While it is unclear if early intervention after the diagnosis of VTE affects clinical outcome, the association with increased length of stay and ICU admission can increase healthcare-associated costs in the current environment with increasing focus on value. Further studies are warranted to characterize the risk factors for VTE in AL population. DisclosuresCarraway:Novartis: Speakers Bureau; FibroGen: Consultancy; Jazz: Speakers Bureau; Amgen: Membership on an entity's Board of Directors or advisory committees; Agios: Consultancy, Speakers Bureau; Balaxa: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Advani:Amgen: Research Funding; Novartis: Consultancy; Glycomimetics: Consultancy; Pfizer: Honoraria, Research Funding. Nazha:MEI: Consultancy. Gerds:Incyte: Consultancy; CTI Biopharma: Consultancy; Apexx Oncology: Consultancy; Celgene: Consultancy. Sekeres:Opsona: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Opsona: Membership on an entity's Board of Directors or advisory committees.

Prophylactic IVC filter placement in bariatric surgery patients: results from a prospective filter registry

BackgroundBariatric surgery patients are at increased risk for VTE, but potential risks versus benefits of IVC filters in this group remain unclear. Indwelling filters may increase risk of VTE, and removal of filters in obese patients can be challenging. This study evaluated the incidence of VTE in select bariatric patients receiving prophylactic IVC filters, their risk of filter-related complications, and outcomes from attempted filter retrieval.ResultsPostsurgical DVT occurred in 3 patients within 3 months postoperatively (3%)(95%CI:1–9%), and 1 patient(1%)(95%CI:0–5%) developed acute low-risk PE at 31 days postoperatively, prior to filter removal. All VTE patients were successfully managed with therapeutic anticoagulation alone except one who required thrombolysis. Median filter dwell time was 54 days (range:22–1548), and there were no major filter-related complications (0%)(95%CI:0–3%). Retrieval was attempted in 104 cases (97%)(95%CI:92–99%) and successful in 104 cases (100%)(95%CI:97–100%). Thirty-three patients (32%)(95%CI:23–42%) required advanced techniques for filter removal, and there were no major procedural complications (0%)(95%CI:0–3%). Median follow-up occurred at 344 days (range:3–1570) days after filter retrieval.ConclusionsNo cases of life-threatening post-op PE occurred in this cohort of high-risk bariatric surgery patients receiving prophylactic IVC filters in combination with mechanical and chemoprophylaxis. The risk of filter-related complications was low and retrieval success was high with adjunctive use of advanced techniques.Clinical trial registrationNCT01158482

Persistently low inferior vena cava filter retrieval rates in a population-based cohort

BackgroundPractice patterns associated with inferior vena cava (IVC) filter placement have seen considerable variation in the last decade. We used a statewide administrative database to examine trends in IVC filter placement and retrieval in the general population. MethodsWe reviewed Florida state inpatient and ambulatory surgery databases from 2004 to 2014. International Classification of Diseases, Ninth Revision diagnosis and procedure codes and Current Procedural Terminology codes were searched for patients undergoing inpatient or outpatient IVC filter placement, and each patient was longitudinally tracked to the time of inpatient or outpatient filter retrieval. For inpatient filter placements, associated diagnoses were reviewed to identify indications for placement. Univariate and multivariate logistic regression models were constructed to identify factors associated with improved retrieval rates. ResultsDuring the 11-year period, 131,791 IVC filter placements were identified, with a 50% increase from 2004 to 2010 and a 24% decline from 2010 to 2014. Median age at filter placement was 71 years (interquartile range, 57-81 years). Mean follow-up after filter placement was 17.3 ± 25.5 months. Only 8637 filters (6.6%) were retrieved. The annual retrieval rate trended upward, from 3.4% in 2004 to 8.5% in 2013 (P < .001). Median filter dwell time was 96.5 days (interquartile range, 44-178 days). Diagnoses associated with filter placement included venous thromboembolism (75.9%), trauma (35.0%), hemorrhage (29.9%), malignant disease (29.4%), and stroke (5.1%). Retrieval rates were highest in younger patients (34.0% in patients younger than 20 years) and lowest in Medicare patients (2.5%). In a multivariate logistic regression model, Medicare was associated with decreased retrieval rates (odds ratio, 0.33; 95% confidence interval, 0.31-0.35; P < .001) after adjusting for age and associated diagnoses. Weaker risk factors included increased age, white race, and diagnoses of deep venous thrombosis, pulmonary embolism, and malignant disease. A trauma diagnosis was associated with improved retrieval. To further investigate the Medicare effect, a propensity score-matched model was created to better account for confounding effects. In this model, Medicare persisted as a risk factor for decreased filter retrieval (odds ratio, 0.43; 95% confidence interval, 0.40-0.46; P < .001). ConclusionsIVC filter placements, after a substantial increase between 2004 and 2010, have been declining since 2010. Retrieval rates in the general population are steadily improving but continue to lag behind those described in center-specific literature. Increased age and Medicare as the primary payer are the strongest risk factors for lack of filter retrieval. Widespread improvements on a national scale are needed to improve the appropriateness of filter placements and to enhance filter retrieval rates.

Cavographic vs. cross-sectional measurement of the inferior vena cava diameter before filter placement: are we routinely oversizing?

A megacava (vena cava with a diameter of 28mm or greater) requires a particular filter to avoid migration. However, caval morphologies are variable. As the inferior vena cava (IVC) usually adopts a circular geometry after a filter is inserted, this study aims (a) to classify caval geometry and orientation; (b) to compare discrepancy between anterioposterior projective diameter (PD) and circumference-based calculated diameter (CD) measurements on cross-sectional computed tomography (CT) images; (c) if a discrepancy exists, determine how often it can affect IVC filter selection. A total of 1503 patients were retrospectively reviewed. Caval morphology was classified. PD and CD were measured at infrarenal IVC. Differences between the PD and CD were assessed by the Wilcoxon signed-rank test or paired t test (if appropriate). The scatterplot of PD vs. CD was used to show whether one is consistently larger than the other. The PD was significantly larger than the CD (22.3 ± 3.5 vs. 20.4 ± 2.8, p < 0.001). The caval morphologies were divided into five types. Type 1 was oval IVC oriented left-anterior-oblique to the horizontal line with an angle (n = 999, 66.5%), type 2 was round IVC (n = 49, 3.3%), type 3 was oval IVC with a vertical long axis (n = 8, 0.5%), type 4 was oval IVC with a horizontal long axis (n = 75, 5.0%), and type 5 was irregularly shaped IVC (n = 372, 24.7%). Patients with round IVC are rare. Measurement of CD may be better to assess maximum IVC diameter compared with PD for the purpose of IVC filter placement. • Five types of IVC orientation are described in this paper: type 1 (n = 999, 66.5%), type 2 (n = 49, 3.3%), type 3 (n = 8, 0.5%), type 4 (n = 75, 5.0%), and type 5 (n = 372, 24.7%). • The incidence of megacava (vena cava with a diameter of 28mm or greater) measured on anterioposterior projective imaging may be overestimated. • As an IVC will adopt a circular geometry following filter placement, circumference-based calculated diameter may be an appropriate approach for caval size determination.

Tools for Simulation; Low Budget and No Budget

Interventional Radiology (IR) incorporates a unique set of technical skills such as ultrasound-guided needle placement, inferior vena cava filter placement, and wire/catheter exchange, which are not easily attained in other aspects of medical training. Simple, low cost models can allow medical students and residents to attain these skills in a low risk setting. These simulated tasks will ultimately combine to improve preparedness of trainees during patient procedures allowing them to advance more quickly through the training paradigm without patient risk. Many commercially available devices may be cost prohibitive, so low cost solutions are presented.

Hidden burden of venous thromboembolism after trauma: A national analysis.

Trauma patients are at increased risk for venous thromboembolism (VTE). One in four trauma readmissions occur at a different hospital. There are no national studies measuring readmissions to different hospitals with VTE after trauma. Thus, the true national burden in trauma patients readmitted with VTE is unknown and can provide a benchmark to improve quality of care. The Nationwide Readmission Database (2010-2014) was queried for patients ≥18 years non-electively admitted for trauma. Patients with VTE or inferior vena cava filter placement on index admission were excluded. Outcomes included 30-day and 1-year readmission to both index and different hospitals with a new diagnosis of VTE. Multivariable logistic regression identified risk factors. Results were weighted for national estimates. Of the 5,151,617 patients admitted for trauma, 1.2% (n = 61,800) were readmitted within 1 year with VTE. Of those, 29.6% (n = 18,296) were readmitted to a different hospital. Risk factors for readmission to a different hospital included index admission to a for-profit hospital (OR 1.33 [1.27-1.40], p < 0.001), skull fracture (OR 1.20 [1.08-1.35], p < 0.001), Medicaid (OR 1.16 [1.06-1.26], p < 0.001), hospitalization >7 days (OR 1.12 [1.07-1.18], p < 0.001), and the lowest quartile of median household income for patient ZIP code (OR 1.13 [1.07-1.19], p < 0.01). The yearly cost of 1-year readmission for VTE was $256.9 million, with $90.4 million (35.2%) as a result of different hospital readmission. Previously unreported, over one in three patients readmitted with VTE a year after hospitalization for trauma, accounting for over a third of the cost, present to another hospital and are not captured by current metrics. Risk factors are unique. This has significant implications for benchmarking, outcomes, prevention, and policy. Epidemiological study, level II.

The association of IVC filter placement with the incidence of postoperative pulmonary embolism following laparoscopic bariatric surgery: an analysis of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Project

BackgroundVenous thromboembolism, including pulmonary embolism (PE) and deep venous thrombosis, is a leading cause of morbidity and mortality after bariatric surgery. Inferior vena cava filters (IVCFs) have been used as a method to reduce the incidence of clinically significant PEs after bariatric surgery. ObjectivesTo compare the incidence of postoperative PEs in patients with IVCFs with those in patients without IVCFs at the time of bariatric surgery. SettingAmerican College of Surgeons Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program. MethodsAll patients undergoing laparoscopic Roux-en-Y gastric bypass or sleeve gastrectomy from 2015 to 2016 were identified within the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database. Patients with an IVCF present at the time of surgery were compared with those patients without an IVCF present at the time of surgery with respect to preoperative patient variables, operative variables, incidence of 30-day PE, deep venous thrombosis, and additional 30-day morbidity and mortality. ResultsA total of 286,704 patients met the inclusion criteria; 2512 (.9%) patients had an IVCF present at the time of surgical intervention, of which 1747 (69.5%) were placed within 30 days of bariatric surgery. Patients with an IVCF were higher-risk patients as determined by previously established risk factors for venous thromboembolism events. When a subgroup matched analysis using variables associated with the risk of venous thromboembolism events was performed looking at higher-risk patients only, there was no statistically significant difference in the incidence of PE based on the presence of an IVCF. ConclusionIVCFs are being selectively placed in higher-risk patients. Despite their selective use, IVCFs do not appear to have a protective benefit with respect to the incidence of postoperative PE events.

Statewide Inferior Vena Cava Filter Placement, Complications, and Retrievals: Epidemiology and Recent Trends

Background:Public awareness of inferior vena cava (IVC) filter-related controversies has been elevated by the Food and Drug Administration (FDA) safety communication in 2010.Objectives:To examine population level trends in IVC filter utilization, complications, retrieval rates, and subsequent pulmon

Solving the Chinese Finger Trap: A Novel Method for Simultaneous Superior and Inferior Vena Cava Filter Removal.

As many as 130,000 inferior vena cava (IVC) filters are placed annually, with as few as 5,000 retrieved a year for patients who no longer require protection from deep vein thrombosis. Superior vena cava (SVC) filter placement is an even less common occurrence and is usually reserved for special cases. Furthermore, the simultaneous placement of IVC and SVC filters is most rare, whereas simultaneous IVC and SVC filter removal has not been reported in the literature. We present a case and a novel technique for successful concurrent removal of IVC and SVC filters in a patient.

THE ROLE OF PATHOPHYSIOLOGY IN BUILDING MEDICAL KNOWLEDGE

Anticoagulation is the primary treatment for pulmonary embolism (PE). Inferior vena cava (IVC) filters are an adjunctive intervention to prevent recurrent pulmonary embolism. Long-term outcomes in elderly patients with contraindications to anticoagulation after IVC filter placement for prevention of recurrent pulmonary embolism have yet to be assessed.Patients ≥ 60 years of age, that had an IVC filter placed between 1 January, 2008 and 2 February, 2013, with a primary diagnosis of pulmonary embolism, were included. Patients that died during index hospitalisation, were discharged to hospice, or had active malignancy were excluded. The primary endpoint was overall survival. Patients were divided depending on whether they were treated with an approved anticoagulant for VTE or had no anticoagulant.Of the 152 patients identified, 55 were not anti-coagulated after IVC filter placement. The incidence of death was 0.4 per 1000 filter days and 0.7 per 1000 filter days in the anti-coagulated and untreated groups respectively (p-value = 0.06). After statistical correction for co-morbid conditions, the effect of anticoagulation was not significant (HR 0.82 CI 0.49–1.37, p-value 0.46). Age was a significant confounder that was associated with death. Increased BMI was protective. Indications for IVC filter placement were numerous, but similar between the two groups.Treatment with an approved anticoagulant is recommended after IVC filter placement for prevention of recurrent PE, however its effect may be attenuated by advanced age. In elderly patients that have undergone IVC filter placement for prevention of recurrent PE, survival may be more dependent on age and co-morbid conditions than exposure to anticoagulation.

Radiology Nursing in the Management of the Acute Stroke Patient: Beyond Emergency Revascularization

Endovascular therapy is now the first-line treatment for acute ischemic stroke secondary to large vessel occlusions. As an important part of the neurovascular triad (radiology, neurology, and neurosurgery), nurses within the specialty of radiology play in important role in emergency revascularization. However, the role of nursing in acute stroke extends beyond timely recanalization, well into the convalescent phase. The purpose of our study was to explore the other important aspects of clinical care performed by diagnostic and interventional radiology nurses in acute stroke. After Institutional Review Board approval, imaging and clinical records of 100 consecutive patients presenting to a tertiary-care center with acute stroke and a large vessel occlusion were reviewed. Hospitalization records were examined for the type and number of interventional radiology-related non-neurovascular procedures performed in this patient population. Non-neurovascular interventional radiology-related procedures were performed in over 40% of patients, most commonly gastrostomy tube placement, IVC filter placement, and peripherally inserted central catheter placement. 28 gastrostomy tubes, 10 IVC filters, and 10 peripherally inserted central catheter lines were placed. The average age of IVC filter placement was 60 years, with a range of 45 to 81 years. Radiology nurses have an important role to play in the management of acute stroke patients, even after patients have undergone revascularization. Educating clinical colleagues and patients about radiology nursing-related services in acute stroke can advance the field of radiology nursing and other advanced practitioners while improving the care of the large number of patients afflicted by acute stroke.

The safety and effectiveness of celect inferior vena cava filter evaluated by CT

Objective To investigate the safety and effectiveness of the Celect inferior vena cava filter (IVCF) in the treatment of deep venous thrombosis (DVT). Methods CT follow-up examinations were performed in 72 patients who underwent Celect inferior vena cava filter placement between August 2015 and September 2017. Forty-five patients (62.5%) presented with DVT alone, 27(37.5%) with DVT and pulmonary embolism (PE). With filters in place, each patient was followed up with CT at least once, to visualize new pulmonary embolism, inferior vena cava occlusion, filter tilting, fracture of struts, migration and penetration of struts through the inferior vena cava. Caval penetration was graded on a five-point scale. Results All Celect filters were successfully deployed. The interval between the filter placement and the CT was 5.0 to 695.0 days, mean (42.4±84.6)days. No new pulmonary embolism, cava occlusion, filter fracture and migration were found. Forty-two (58.3%) filters tilted, including tilt>15 degrees in 8 (11.1%) and tilt ≤15 degrees in 34 (47.2%). Caval penetration with 0 grade was observed in 47 (65.3%) and beyond grade 1 was observed in 25 (34.7%), including grade Ⅰ in 12 (16.7%), grade Ⅱ in eight (11.1%), grade Ⅲ in four (5.6%) and grade Ⅳ in one (1.4%). No patient presented with symptoms associated with caval penetration. Filter retrieval was attempted in 54(75.0%) patients,the indwell time was 5.0 to 111.0 days, mean(32.0±23.9) days. There were 52 (96.3%) filters successfully removed, including four filters tilted lead retrieval hook embedded the caval wall, which used the adjunctive retrieval techniques. Filter retrieval failure in two (3.7%) cases, including one case retrieval hook embedded the caval wall and the other with retrieval hook penetration. Conclusions Celect inferior vena cava filter can effectively prevent PE, but had a tendency to tilt and to penetrate caval wall, which affected the filter retrieval, and had the potential risk of serious complications such as abdominal aortic pseudoaneurysm. The filter should be removed as soon as the risk of PE is manageable. We advocate CT follow-up for patients with long-term inferior vena cava filter placement. Key words: Vena cava filters; Venous thrombosis; Lower extremity; Tomography, X-ray computed

Administration routes affect thrombolytic effect of catheter-directed thrombolysis with pro-urokinase in treating deep vein thrombosis.

Deep venous thrombosis (DVT) is a common disorder with a significant mortality rate. Catheter-directed thrombolysis (CDT) is a preferred treatment for DVT patients. The aim of this study is to evaluate the thrombolytic effect of CDT with pro-urokinase (pro-UK) in different administration routes. An inferior vena cava (IVC) model was induced in 36 New Zealand white rabbits by catheter injury and placement of IVC filter. The animals were divided into 6 groups with 6 rabbits in each group: group A: systemic thrombolysis with intravenous injection; group B: CDT with pump infusion; group C: CDT with pulse injection; group D: CDT with combination of pump infusion and pulse injection; group E: catheter-directed aspiration thrombectomy; group F: mechanical thrombectomy. The thrombolytic effects were evaluated by color Doppler ultrasound and blood measurement of D-dimer and fibrinogen. The minimum effective concentration of pro-UK solution was identified. Two groups (group A and B) did not achieve successful thrombolysis. Among all catheter-directed administration groups, the rabbit groups that received pro-UK therapy through catheter-directed thrombolytic pump infusion combined with pulse injection (group D) showed the best thrombolysis effect. In contrast, catheter-directed aspiration thrombectomy (group E) is effective but not safe. CDT with combination of pump infusion and pulse injection of pro-UK safely and significantly improves thrombolysis procedure in rabbits, suggesting potential benefits from the use of CDT in proximal DVT.

Optimal timing of initiation of thromboprophylaxis in spine trauma managed operatively: A nationwide propensity-matched analysis of trauma quality improvement program.

Patients with spinal trauma are at high risk for venous thromboembolic events (VTE). Guidelines recommend prophylactic anticoagulation but they are unclear on timing of initiation of thromboprophylaxis. The aim of our study was to assess the impact of early versus late initiation of venous thromboprophylaxis in patients with spinal trauma who underwent operative intervention. We performed a 2-year (2013-2014) review of patients with isolated spine trauma (spine-Abbreviated Injury Scale score, ≥ 3 and no other injury in another body region with Abbreviated Injury Scale score, > 2) who underwent operative intervention and received thromboprophylaxis postoperatively. Patients were divided into two groups based on the timing of initiation of thromboprophylaxis: early(<48 hours) and late(≥48 hours), and were matched in a 1:1 ratio using propensity score matching for demographics, admission vitals, injury parameters, type of operative intervention, hospital course, and type of prophylaxis(low molecular weight heparin vs. unfractionated heparin). Outcomes were rates of deep vein thrombosis (DVT) and/or pulmonary embolism, red-cell transfusions, the rate of operative interventions for spinal cord decompression and mortality after initiation of thromboprophylaxis. Nine thousand five hundred eighty-five patients underwent operative intervention and received anticoagulants, of which 3554 patients (early, 1,772; late, 1,772) were matched. Matched groups were similar in demographics, injury parameters, emergency department vitals, hospital length of stay, rates of inferior vena cava (IVC) filter placement and time to operative procedure. Patients who received thromboprophylaxis within 48 hours of operative intervention, unlike those who did not, were less likely to develop DVT (2.1% vs. 10.8%, p < 0. 01). However, the rate of pulmonary embolism was similar in both groups (p = 0.75). Additionally, there was no difference in postprophylaxis red cell transfusion requirements (p = 0.61), rate of postprophylaxis decompressive procedure on the spinal cord (p = 0.27), and mortality (p = 0.53). Early VTE prophylaxis is associated with decreased rates of DVT in patients with operative spinal trauma without increasing the risk of bleeding and mortality. The VTE prophylaxis should be initiated within 48 hours of surgery to reduce the risk of DVT in this high-risk patient population. Therapeutic studies, level IV.

Management of Venous Thromboembolism in Pregnancy.

This manuscript addresses the risks for venous thromboembolism (VTE) during pregnancy and the associated challenges of both diagnosis and treatment. The obstacles to diagnosis given lack of specificity of typical biomarkers to predict VTE in pregnancy, as well as the unique fetal and bleeding risks introduced by managing massive pulmonary embolism (PE) with thrombolytics or thrombectomy are highlighted. VTE during pregnancy and the postpartum window occurs at a 6-10-fold higher rate compared with age-matched peers and is a major cause of morbidity and mortality. Hypercoagulability persists for 6-8weeks after delivery with the highest risk of PE being postpartum. The lack of randomized trials in pregnant women leads to variability in practice, which are largely based on expert consensus or extrapolation from non-pregnant cohorts. The standard treatment of VTE in pregnancy is anticoagulation with low molecular weight heparin (LMWH), which like unfractionated heparin does not cross the placenta and is not teratogenic. LMWH is preferred given the negligible risk for heparin-induced thrombocytopenia and osteoporosis, better bioavailability, and a predictive dose response. Depending on the severity of the VTE, additional treatments including thrombolysis, thrombectomy, inferior vena cava filter placement, or venous stenting may be used. Management requires balancing the competing bleeding and thrombotic risks during labor and delivery and factoring the impact of treatment on the fetus. A multidisciplinary team involving hematology, obstetrics, anesthesia, vascular medicine, and cardiology is critical for safe and timely management. The design and execution of prospective, randomized trials to specifically address optimal diagnosis and management are a top priority in obstetric hematology.

In-Hospital Mortality Benefit of Inferior Vena Cava Filters in Patients With Pulmonary Embolism and Congestive Heart Failure.

Pulmonary embolism (PE) is associated with a higher mortality rate in patients with congestive heart failure (CHF) than in those without heart failure. The purpose of this study was to evaluate if inferior vena cava (IVC) filter placement provides any mortality benefit in patients admitted with CHF and PE. The 2005-2014 Nationwide Inpatient Sample (NIS) was used for this study. Adults (≥ 18 years old) with PE were identified using International Classification of Diseases, 9th revision, Clinical Modification (ICD-9-CM) diagnosis codes. Patients with CHF were identified using the Elixhauser comorbidity variable (CM_CHF) in the NIS database. IVC filter placement was identified using the ICD-9-CM procedure code 38.7 (interruption of the vena cava). A multivariate logistic regression model was used to determine the association of IVC filter placement with in-hospital mortality. The model was adjusted for demographics, hospital characteristics, comorbidities, and PE severity indexes (pressor dependence, mechanical ventilation, nonseptic shock, and use of thrombolytic therapy). During the study years, 425,877 patients with a comorbidity of CHF were hospitalized with PE (44% male; mean age, 71.5 years old). Of them, 67,237 patients (15.8%) received an IVC filter during the admission, and 50,338 (11.8%) died during the hospital stay. The all-cause in-hospital mortality rate among patients who received an IVC filter was 9.7% (6541 of 67,237 patients) compared with 12.2% (43,796 of 358,638 patients) among those without an IVC filter (p < 0.001), with an absolute risk reduction of 2.5%. The multivariate adjusted hazard ratio of in-hospital mortality associated with IVC filter placement was 0.535 (95% CI, 0.518-0.551; p < 0.001). A lower all-cause mortality rate was observed in patients with CHF and PE who received an IVC filter while hospitalized. In the absence of data from randomized controlled trials, this study suggests that IVC filters could help prevent in-hospital death among patients admitted with PE and CHF.