Inferior Vena Cava Filter Implantation Research Articles

Safety and Outcomes of Inferior Vena Cava Filter Placement in Oncology Patients: A Single-Centre Experience.

The risk of venous thromboembolism (VTE) in the oncology population is significantly higher than in non-cancer patients. Inferior vena cava (IVC) filters may, therefore, be an important part of VTE treatment. In this study, we address the outcomes of placing IVC filters in the oncology population. This single-centre, observational, retrospective study included 62 patients with active malignancy and acute VTE who underwent an IVC filter implantation due to contraindications to anticoagulation during the period 2012-2023. The control group consisted of 117 trauma patients. In both groups, an urgent surgical procedure requiring temporary cessation of anticoagulation was the most noted reason for IVC filter placement-76% in the oncology group vs. 100% in the non-oncology group (p < 0.001). No complications were reported during the IVC filter implantation procedures. There was no recurrence of pulmonary embolism or deep venous thrombosis in the oncology group after filter implantation. The rate of successful filter explantation, median time to retrieval, and abnormal findings during retrieval were not significantly different between both subgroups (64.3% vs. 76.5%, p = 0.334; 77 days vs. 84 days, p = 0.764; 61.5% vs. 54.2%, p = 0.672; respectively). The study showed that IVC filter placement is a safe and effective method of preventing PE in cancer patients with contraindications to anticoagulation. The complication rate following IVC filter implantation in cancer patients is low and similar to that in non-oncology patients.

Independent association between IVC filter placement and VTE risk in patients with upper gastrointestinal bleeding and isolated distal DVT: A retrospective cohort study.

The placement of inferior vena cava (IVC) filters often emerges as an alternative preventative measure against pulmonary embolism in patients with upper gastrointestinal (GI) bleeding and isolated distal deep vein thrombosis (DVT). We aimed to investigate the association of IVC filter placement and the incidence of venous thromboembolism (VTE) recurrence in this patient population. We performed a retrospective cohort study including 450 patients with upper GI bleeding and isolated distal DVT. Propensity score matching using logistic regression was conducted to mitigate potential selection bias. Logistic regression models and additional sensitivity analyses were conducted to estimate the association between IVC filter implantation and VTE recurrence. Interaction and stratified analyses were also performed according to the background covariates. Patients who underwent IVC filter placement were significantly younger than patients in the surveillance group (55.8 ± 9.0 vs 58.4 ± 11.2 years, p = 0.034). Patients in the IVC filter group demonstrated a higher distal thrombus burden. The VTE recurrence composite was significantly higher in patients who underwent IVC filter placement (44.1% [45/102] vs 25% [87/348], p < 0.001). Unmatched crude logistic regression analysis identified a significant association between IVC filter placement and VTE recurrence composite (OR = 2.37; 95% CI, 1.50-3.75). Sensitivity analyses yielded congruent outcomes. This study revealed an increased risk of VTE recurrence among patients receiving IVC filter placement, suggesting that IVC filter placement may not be suitable as a primary treatment for patients with upper GI bleeding and isolated distal DVT.

Oral Rivaroxaban Versus Warfarin After inferior Vena cava Filter Implantation: A Retrospective Cohort Study.

To assess the efficacy and safety of rivaroxaban compared to warfarin after inferior vena cava (IVC) filter implantation. This retrospective analysis includes data from 100 patients with deep vein thrombosis (DVT) who underwent IVC filter implantation due to a free-floating thrombus (n = 64), thrombus propagation (n = 8), or acute bleeding (n = 8) on therapeutic anticoagulation, catheter-directed thrombolysis (n = 8), or had previously implanted filter with DVT recurrence. Patients were treated with warfarin (n = 41) or rivaroxaban (n = 59) for 3-12 months. Symptomatic venous thromboembolism (VTE) recurrence and bleeding events were assessed at 12 months follow-up. Three (7.3%) cases of VTE recurrence without IVC filter occlusion occurred on warfarin and none on rivaroxaban. The only (2.4%) major bleeding occurred on warfarin. Three (5.1%) clinically relevant non-major bleedings were detected on rivaroxaban. No significant differences existed between groups when full and propensity scores matched datasets were compared. Rivaroxaban seems not less effective and safe than warfarin after IVC filter implantation.

Contemporary Use of Prophylactic Inferior Vena Cava Filters in Patients With Severe Traumatic Injuries and High Thromboembolic Event Risk

PurposeThe aim of this study was to evaluate the relationship between prophylactic inferior vena cava filter (IVCF) implantation and in-hospital deep vein thrombosis (DVT), pulmonary embolism (PE), and mortality among adults with intracranial, pelvic or lower extremity, and spinal cord injuries. MethodsPatients 18 years and older with severe intracranial, pelvic or lower extremity, or spinal cord injuries captured by the Trauma Quality Improvement Program (2010-2019) were identified. IVCFs implanted ≤72 hours after hospital presentation and before performance of lower extremity ultrasonography were defined as prophylactic. Patients were stratified by pharmacologic venous thromboembolism (VTE) prophylaxis status. Logistic regression models estimated prophylactic inferior vena cava (IVC) filtration’s effect on selected outcomes and identified attributes associated with prophylactic IVCF implantation. ResultsOf 544,739 included patients, 1.3% (n = 7,247) underwent prophylactic IVCF implantation. Among patients who received pharmacologic VTE prophylaxis, prophylactic IVC filtration compared with expectant management was positively associated with DVT (odds ratio [OR], 4.30; P < .001) and PE (OR, 4.30; P < .001) but not associated with mortality (OR, 0.92; P = .43). Among patients who received no pharmacologic prophylaxis, prophylactic IVC filtration was positively associated with DVT (OR, 4.63; P < .001) and PE (OR, 5.02; P < .001) but negatively associated with mortality (OR, 0.43; P < .001). ConclusionsProphylactic IVC filtration was associated with increased likelihood of VTE among all adults with severe intracranial, pelvic or lower extremity, and spinal cord injuries. In patients who received no pharmacologic VTE prophylaxis, prophylactic IVC filtration was associated with decreased likelihood of in-hospital mortality.

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

In this study, we examined the safety and effectiveness of removing inferior vena cava (IVC) filters with residual acute thrombosis after endovascular therapy. A retrospective chart review of 712 patients who underwent retrievable IVC filter implantation between July 2018 and December 2022 was conducted. Residual thrombosis with the IVC filter occurred in 18 patients, and the volume of residual acute thrombosis in the IVC filter exceeded 1mL in all cases. Angiography was performed to evaluate the size of the residual thrombosis and its position with respect to the filter. The double series filter technique (first filter, infrarenal IVC filter; second filter, suprarenal IVC filter) was used to remove the filter and thrombosis. We summarize the diagnosis, treatment, and surgical experience of these patients. In this study, 16 of 18 patients (88.9%) demonstrated residual thrombosis in the IVC filter. One patient (5.6%) demonstrated thrombosis located both inside and floating above the filter, and one patient (5.6%) demonstrated thrombosis located both inside and underneath the filter. The technical success rate of double series IVC filter retrieval was 100%. Seventeen patients (94.4%) underwent single-stage suprarenal IVC filter retrieval, and one patient (5.6%, 1/18) underwent two-stage retrieval. In terms of residual thrombosis removal, 14 patients (77.7%) achieved complete removal and 4 patients (22.3%) achieved partial removal. Residual thrombosis could not be removed through the sheath in one patient, so femoral vein thrombectomy was performed. No other procedure-related complications were observed. The median follow-up time was 22.5±6.8months. No recurrence of thrombus symptoms was reported, and B ultrasound and computed tomography demonstrated smooth blood flow in the IVC, renal veins, and pulmonary artery. For patients with residual acute thrombosis on the IVC filter and in whom there was absence of a more appropriate treatment after percutaneous mechanical thrombectomy or catheter-directed thrombolysis therapy, the double series IVC filter technique was a safe approach to improve the IVC filter retrieval rate in the early stage, as well as for simultaneous residual thrombus removal.

Abstract 14256: Examining the Efficacy of Inferior Vena Cava Filters in the Direct Oral Anticoagulant Era

Introduction: No previous reports have adequately demonstrated whether inferior vena cava filters prevent pulmonary embolism, and reports of disadvantages, such as worsening venous thrombosis, have led to a decrease in the frequency of their use. However, in actual clinical practice, patients often encounter situations in which they expect to benefit from inferior vena cava filters; hence, exploratory studies examining their efficacy continue. Hypothesis &amp; Methods: We analyzed data from the COMMAND VTE Registry-2, a multi center, retrospective, observational study of symptomatic venous thrombosis in the DOAC era, for cases using inferior vena cava filters. Results: A total of 5197 cases of venous thrombosis were enrolled, among whom 483 (9%) had inferior vena cava filters implanted. The inferior vena cava filter was implanted long-term and removed in 6% and 3% of cases, respectively. Inferior vena cava filters tended to be implanted in patients with active cancer patients, with more patients with terminal cancer, on anticancer therapy, and with distant metastases having long-term filter implantation (P = 0.001). After inferior vena cava filter implantation, the inferior vena cava filter implantation group showed a significantly lower incidence of pulmonary embolism within 30 days after the onset of initial venous thrombosis (P = 0.011). However, Kaplan-Meier analysis during a median follow-up of 854 days showed that long-term implantation of inferior vena cava filters significantly increased incidence of deep vein thrombosis (P = 0.001), whereas multivariate analysis found that long-term implantation of inferior vena cava filters was an independent risk factor for deep vein thrombosis (HR: 2.096, 95% CI: 1.254-3.508, P = 0.005). Conclusions: Inferior vena cava filters may be effective in preventing pulmonary emboli in the short term; however, even in the DOAC era, long-term filter implantations were associated with an increased incidence of deep vein thrombosis.

Investigation of the Effects of an Inferior Vena Cava Filter and Captured Clot Size on the Hemodynamic Parameters in Non-Newtonian Turbulent Pulsatile Blood Flow

In this computational fluid dynamics (CFD)-based study, the effects of inferior vena cava (IVC) filter implantation on the risk of IVC thrombosis have been investigated using different hemodynamic parameters, including time-averaged wall shear stress (TAWSS), the oscillating shear index (OSI), and the relative residence time (RRT). The boundary conditions in this study have been based on physiological pulses. Additionally, the k–ω model and the Carreau model have been chosen to represent the turbulent flow regime and non-Newtonian blood, respectively. For this purpose, three blood clots with the largest cross-sectional diameters of 30%, 50%, and 70% of the filter diameter have been used. Capturing a small clot in the filter has the minimum effect on the hemodynamic parameters, while by increasing the size of the captured clot, OSI and RRT parameters increase in areas downstream of the filter on the wall. The presence of a filter and clot increases the risk of thrombosis. In the case of capturing large clots, there is the possibility of damage to endothelial cells or platelet activation. Captured clots lead to the formation of plaque and thrombus on the IVC wall. However, the possibility of thrombus growth on its surface is not negligible, particularly if larger clots are trapped in the filter.

Embolization and bleeding in patients with anticardiolipin antibodies

The patient, a 32-year-old male, was positive for anti-cardiolipin antibody syndrome and had a history of smoking for 15 years. He underwent “inferior vena cava filter implantation + catheter hemolysis” 10 years ago due to deep vein thrombosis of the right lower limb. After surgery, he continued to take farwarin and aspirin orally. Three years ago, due to thrombosis again, intravenous thrombolysis was performed in the lower extremity. After surgery, pharhualin was taken orally continuously. Massive hemoptysis occurred after intense exercise and eating spicy stimulating food 5 months ago. DSA showed abnormal bleeding in the right bronchial artery and right internal thoracic artery, so 300-500 um microsphere was used to embolize the peripheral artery. 350-560 um PVA granules embolized bronchial arteries; Three months ago, due to the recurrence of hemoptysis after oral administration of TCM blood-promoting drugs, angiography showed an increase in the number of responsible arteries, abnormal bleeding of the left bronchial artery and the right upper lobar bronchial artery of the lung segment, the formation of the middle and lower lobar bronchial artery of the right lung segment and the formation of collateral circulation of the right internal thoracic artery. Embolization of the above arteries was performed, and the patient recovered well after surgery and was discharged from hospital.

Endovascular Low-Pass Filter: Performing Mitral Edge-to-Edge Repair With PASCAL Through an Inferior Vena Cava Filter

We present the case of an 82-year-old man with a history of inferior vena cava filter implantation and concomitant severe mitral regurgitation requiring transcatheter edge-to-edge repair. Despite being deemed ineligible for transfemoral access as technically challenging, he successfully underwent mitral transcatheter edge-to-edge repair after crossing and dilatation of the inferior vena cava filter. (Level of Difficulty: Intermediate.)

Clinical Observation of Uninterrupted Thrombolytic Therapy via Indwelling Catheter for Lower Limb Deep Vein Thrombosis.

Observe uninterrupted thrombolytic therapy via indwelling catheter for lower limb deep vein thrombosis. We retrospectively studied data from 32 patients with lower extremity deep vein thrombosis who received comprehensive treatment, consisting of general treatment, inferior vena cava filter implantation, interventional thrombolysis, angioplasty, stenting, and post-operative monitoring. The efficacy and safety of the comprehensive treatment were observed for a follow-up period of 6-12 months. The treatment was 100% effective; patient results indicated no serious bleeding, acute pulmonary embolism, or death after surgery. The combination of intravenous and healthy side femoral vein puncture and directed thrombolysis to treat acute lower limb deep vein thrombosis is safe, effective, and minimally invasive while still achieving a good therapeutic effect.

One filter may be enough for duplicate inferior vena cava filter implantation in patients with deep venous thrombosis: Two cases report

Duplicate inferior vena cava (IVC) is an uncommon congenital malformation, but should be treated carefully under the circumstances of deep venous thrombosis (DVT). However, there is a paucity of clinical guidance on this situation. Duplicate IVC was diagnosed based on the imaging examination that revealed the dual IVC. Deep venous thrombosis was diagnosed by Compression Doppler ultrasonography of both lower extremities with the high-elevated D-dimer. Retrievable IVC filters were implanted to prevent massive and fatal pulmonary embolism. Appropriate anticoagulation therapy was also performed. Two retrievable filters were successfully implanted and retrieved in two patients with deep venous thrombosis and duplicate inferior vena cava, respectively. During further follow-up, no adverse event was reported. Comprehensive imaging examination might contribute to the diagnosis of duplicate IVC, especially when individual conditions were limited. The position above the confluence of bilateral IVCs might be an appropriate suprarenal retrievable filter insertion location. To deal with different types of dual IVC anatomy, different strategies should be taken into consideration.

Abstract No. 146 Risk factors for development of IVC thrombosis in inferior vena cava filter bearing patients

Inferior vena cava filter (IVCF)-related iliocaval thrombosis is a complication with significant morbidity; however, data on its prevalence and risk factors predisposing to its occurrence are sparse, outdated, and highly inconsistent. This study aims to elucidate the incidence of caval thrombosis in modern practice settings and identify factors which increase the risk of iliocaval thrombosis following IVCF implantation.

Long-Term Outcomes in Patients with Not-Retrieval Inferior Vena Cava Filter Under Anticoagulation.

Since permanent inferior vena cava (IVC) filters increase deep vein thrombosis (DVT), filter retrieval should be performed as possible. Despite the guideline recommendation, IVC filters are not always retrieved in clinical practice. To date, many patients with not-retrieval IVC filters have been prescribed anticoagulant therapy, but the long-term prognosis, including venous thromboembolism (VTE) and bleeding events, remains unknown. In this study, 195 patients who underwent IVC filter implantation between 2006 and 2017 at 3 institutions in Niigata City have been investigated about their deaths, VTE recurrence, and bleeding events. After peaking 2009, the number of IVC filter implantation gradually decreased. During observational period, there were 158 patients with not-retrieval IVC filters (the overall retrieval rate of 19.0%). The not-retrieval group included significantly older and more patients with cancer compared to the retrieval group. Anticoagulation therapy was continued in 88% of the not-retrieval group. During a mean follow-up of 5.0 years, 6 symptomatic DVT events associated with inadequate control of anticoagulation and 13 bleeding events were observed. A total of 52 patients died and only the presence of cancer was prognostic risk factor. Although long-term anticoagulation therapy may be associated with bleeding events, there were few recurrent VTE under optimal anticoagulation. It is anticipated that even if the IVC filter cannot be retrieved, appropriate anticoagulation is useful for prevention of DVT recurrence despite the risk of bleeding.

Analysis of the Occurrence of Acute Pulmonary Embolism in the ICU Ward and Related Risk Factors Predicting Its Severity.

To investigate the occurrence of acute pulmonary embolism in the intensive care unit (ICU) and analyze the related risk factors for predicting its severity. From January 2016 to December 2020, 83 patients with acute pulmonary embolism in the intensive care unit of Peking University People's Hospital were selected as the research subjects, including 34 males (40.96%) and 49 females (59.04%), with an average age of 62.06±16.83 years. The patients were divided into a high-risk group (N = 31), medium-risk group (N = 32), and low-risk group (N = 20), according to the guidelines for diagnosis and treatment of acute pulmonary embolism issued by ASH in 2020. The clinical characteristics, treatment, and prognosis of the three groups were summarized, and the severity of the patients could be predicted and the related risk factors affecting prognosis were analyzed. There were significant statistical differences in respiratory rate, syncope as the first symptom, bilateral pulmonary embolism, and APACHE-II score among the three groups (P < 0.05). There were significant statistical differences in the laboratory indexes, such as BNP, cTnI and D-dimer before and immediately after APE among the three groups (P < 0.05). There were significant statistical differences in cTnI and D-dimer among the three groups (P < 0.05). By pairwise comparison, it was found that there were significant statistical differences between the high-risk and low-risk groups in the immediate test indexes of APE, such as BNP, D-dimer, lower extremity vascular ultrasound abnormalities, and ECG abnormalities (P < 0.05), while there was no significant statistical difference between the medium-risk and low-risk groups in the immediate test indexes of APE (P > 0.05). However, in the medium-risk group, the laboratory indexes tended to increase, in terms of treatment and outcome, thrombolysis rate, and inferior vena cava filter implantation rate. ICU stay (> 2 weeks) of the high-risk group was significantly higher than those of the other two groups, with significant statistical difference (P < 0.05). Logistic regression analysis showed that respiratory rate (or = 1.778,95% CI 1.043-3.032, P = 0.034), D-Dimer (or = 1,95% CI 1.0-1.0, P = 0.006), and APACHE-II score (or = 1.879,95% CI 1.398-2.527, P = 0.000) were independent risk factors for predicting the severity of APE patients in the ICU ward. Acute pulmonary embolism (APE) is a critical disease in ICU. By monitoring BNP, cTnI and D-dimer, we can identify critical patients with APE early. In addition, we found that respiratory rate, D-dimer, and APACHE-II score were independent risk factors for predicting the severity of APE patients in the ICU. Clinically, APE can be identified early. The diagnosis, treatment rate, and prognosis can be improved by monitoring these indicators.

Inferior Vena Cava Filter Utilization at Kingston Health Sciences Centre: A Comparison of Practice with Guidelines

Background: Inferior vena cava (IVC) filters offer mechanical protection against pulmonary embolism in high risk patients. Guidelines have recommended their use be limited. “Don't use inferior IVC filters routinely in patients with acute venous thromboembolism” (ASH Choosing Wisely, 2013). “For patients with acute VTE who are treated with anticoagulation, the guideline recommends against the use of an inferior vena cava filter.” (CHEST Antithrombotic Therapy and Prevention of Thrombosis, 2016) IVC filters implanted for longer than 100 days confer a significantly higher risk of complications (Odds Ratio 2.3, Dinglasan et al. 2013). We sought to determine compliance with these recommendations at Kingston Health Sciences Center (KHSC), an academic tertiary referral center with 440 inpatient beds at Queen's University in Kingston, Ontario, Canada.Methods: Approval was obtained from the Queen's Health Services Research Ethics Board.Consecutive patients with IVC filter implantation at KHSC from August 1st, 2013 to August 1st, 2016 were identified through Interventional Radiology records. All charts were retrospectively reviewed in depth by one investigator followed by review and discussion. Data extracted included: patient demographics and disposition, details surrounding IVC filter insertion and removal, and IVC filter related complications. The indication for filter implantation was classified as clearly consistent or not clearly consistent with CHEST guidelines. The category ‘lesser indication’ was subsequently added for cases of a more subjective nature where definitive categorization was challenging.Results: Between August 2013 and August 2016, 95 IVC filters were implanted at KHSC. Among these, 42 (44.2%) patients were male and the median age was 67 (ages ranged from 17 to 91). The most responsible services ordering IVC filter implantation were Critical Care Medicine (37.9%), Internal Medicine (32.6%), Surgery (12.6%) and other services such as Neurology, Family Medicine and Emergency Medicine (16.9%).Complications arose in 21 patients (22.1%) including filter-associated thrombosis (11), filter migration or tilt (8), IVC penetration (5), IVC perforation (2), and one instance of suspected IVC filter seeding with methicillin sensitive Staphylococcus aureus (MSSA) leading to bacteremia. The mean dwell time of filters that were successfully removed (n=52, 54.7%) was 69.2 days, with thirteen (18.1%) remaining indwelling beyond 100 days. Of those in whom the filter was not removed (n=43), unsuccessful retrieval attempts were made in eight, 23 patients died with their filters in situ within 100 days of implantation, and in 12 patients no record of an attempt to retrieve the device was found.Indication for IVC filter insertion was clearly consistent with CHEST guidelines in 58 (61.1%) patients. Insertion alongside therapeutic anticoagulation/thrombolysis or for prophylaxis in patients without VTE occurred in 26 patients (27.4%) and was considered not consistent with current recommendations. In 8 (8.4%) patients, a ‘lesser indication’ was identified. Lesser indications included cases where there was a need to withhold anticoagulation for less than 24 hours for procedures or surgeries, such as endoscopic retrograde cholangiopancreatography (ERCPs) or ankle open reduction internal fixations (ORIFs). Three charts had insufficient information to determine compliance.Discussion: The main limitation of this study is its retrospective nature with reliance on chart documentation. In addition, it is recognized that guidelines surrounding IVC filter use do not apply to all possible clinical scenarios. Nonetheless, restricting the use of IVC filters to appropriate indications is an important endeavour. These devices are costly, can cause harm, and do not have a strong evidentiary basis. Educational initiatives are underway to optimize use of IVC filters at KHSC. Additional interventions under consideration include development of a specific requisition form listing recommended indications, and creation of an IVC filter insertion database as a prompt for timely removal. DisclosuresHay:Celgene: Research Funding; Roche: Research Funding; Abbvie: Research Funding; Kite: Research Funding; Amgen: Research Funding; Janssen: Research Funding; Novartis: Research Funding.

Venous thromboembolism in non-COVID-19 population during the pandemic: a nationwide multicenter retrospective survey.

Impact of pandemic on the incidence of venous thromboembolism (VTE) in non-COVID-19 patients is undetermined. Thus, a nationwide multicenter retrospective survey was conducted to evaluate the disease burden in non-COVID-19 population. This multi-center survey involved 94 hospitals from 24 provinces in the mainland of China, and collected data on non-COVID-19 patients admitted to the radiology departments due to VTE between January 24 and April 16, 2020. Baseline characteristics, VTE risk factors, clinical manifestations and the treatments were compared with those in the same period of 2019. 3,358 patients with VTE from 74 hospitals were included in this study (1,458 in 2020, 1,900 in 2019). Most aged ≥ 50 years (80.6% in the pandemic, 81.2% in 2019). The number of patients aged 30–39 years increased from 3.9% in 2019 period to 5.8% in the pandemic (p = 0.009). Among the VTE risk factors, the rate of decreased activity increased significantly in the pandemic, and was much higher than that in 2019 (30.7% vs 22.6%, p < 0.0001). Under the risk of decreased activity, patients with comorbidities chronic diseases, especially diabetes, showed significantly a higher incidence of VTE (30.4% vs 22.0%, p < 0.0001). In the pandemic period, fewer patients were treated with anticoagulation alone (33.5% vs 36.7%, p = 0.05), and more underwent inferior vena cava filter (IVCF) implantation, compared with those in 2019 (66.5% vs 63.2%, p = 0.046). The pandemic increased the VTE risk of decreased activity among the non-COVID-19 population. Patients with comorbidities, especially diabetes, have a significant higher risk of VTE during the pandemic.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11239-021-02442-2.

Double inferior vena cava filter implantation in a patient with duplication of the inferior vena cava

An 84-year-old-woman was admitted because of syncope and dyspnea. She also required surgery for lumbar disc herniation. Computed tomography revealed bilateral massive pulmonary thromboembolism, deep vein thrombosis, and duplication of the inferior vena cava (IVC) in which the left IVC had merged with the left renal vein. Two retrievable IVC filters were deployed in both IVCs, and direct oral anticoagulant therapy was started. After orthopedic surgery for the lumbar disc herniation, the IVC filters were retrieved. No complications occurred. Different treatment strategies could be required for IVC filter implantation in a patient with duplication of the IVC.

Nonnegligible causes of symptoms of acute lower extremities\u2014\u20143 cases of May-Thurner syndrome with deep vein thrombosis

BackgroundMay-Thurner syndrome is a kind of disease caused by the compression of the left common iliac vein. It is one of the causes of incomplete venous valves and superficial varicose veins in lower limbs, and is also a potential factor of acute deep vein thrombosis (DVT).MethodHere 3 cases are diagnosed as May-Thurner syndrome at different ages.Case presentations1. A 35-year-old female patient was hospitalized with swelling of the left lower limb for 1 week. Computed tomography (CT) showed compression of the left common iliac vein with thrombosis. May-Thurner syndrome was diagnosed and catheter-directed thrombolysis was performed. 2. A 37-year-old male patient came to our hospital due to sudden swelling of the right lower extremity and pain for 3 days. Computed tomography showed compression of the left common iliac vein and deep venous thrombosis (DVT) of the right iliac vein. May-Thurner syndrome was diagnosed. The patient was performed with inferior vena cava (IVC) filter implantation, catheter-directed thrombolysis and balloon angioplasty for right iliac vein. And the patient recovered well; 3. A 55-year-old female patient came to our hospital with swelling and discomfort in the left lower extremity for 3 days. Computed tomography showed stenosis of the left common iliac vein with deep vein thrombosis. May-Thurner syndrome was diagnosed, balloon dilation and stent implantation were performed. During 3 years of follow-up, there was no swelling or new thrombosis in her lower limbs.ConclusionWhen encountering unexplained deep vein thrombosis, iliac vein compression syndrome should be considered and treated in time to prevent the recurrence of thrombosis. Catheter-directed thrombolysis can relieve symptoms and stenting placement is the optimal way to relieve stenosis, supplemented by long-term anticoagulation therapy and graduated compression stockings.

A world's first attempt of mixed-reality system guided inferior vena cava filter implantation under remote guidance of 5G communication.

A world's first attempt of mixed-reality system guided inferior vena cava filter implantation under remote guidance of 5G communication.

Rationale of bedside ultrasound-guided inferior vena cava filter implantation in COVID-19 patients with deep venous thrombosis.

Rationale of bedside ultrasound-guided inferior vena cava filter implantation in COVID-19 patients with deep venous thrombosis.