Temporal trends in vena cava filter implantation in public health system inpatients: an 11-year analysis of the largest city in Brazil / Tendência temporal do implante de filtro de veia cava em pacientes internados no SUS em São Paulo: análise de 11 anos da maior cidade do Brasil

Abstract Background Vena cava filter implantation is considered a simple procedure, which can lead to overuse and over-indication. It is nevertheless associated with short and long-term complications. Objectives The goals of this study were to evaluate rates of vena cava filter implantation conducted by Brazil's Unified Public Health System, analyzing in-hospital mortality and migration of patients from other cities seeking medical attention in São Paulo. Methods This study analyzed all vena cava filter procedures conducted from 2008 to 2018 in the city of São Paulo and registered on the public database using a big data system to conduct web scraping of publicly available databases. Results A total of 1324 vena cava filter implantations were analyzed. 60.5% of the patients were female; 61.7% were under 65 years old; 34.07% had registered addresses in other cities or states; and there was a 7.4% in-hospital mortality rate. Conclusions We observed an increase in the rates of use of vena cava filters up to 2010 and a decrease in rates from that year onwards, which coincides with the year that the Food and Drug Administration published a recommendation to better evaluate vena cava filter indications.

Resumo Contexto O implante de filtro de veia cava é considerado um procedimento de baixa complexidade, o que pode resultar em indicação excessiva. No entanto, não é isento de complicações a curto e longo prazo. Objetivos Avaliar as taxas de implantes de filtro de veia cava realizados pelo Sistema Único de Saúde e a origem geográfica e mortalidade intra-hospitalar dos pacientes. Métodos Foi conduzida uma análise em um banco de dados públicos referente às taxas de implantes de filtro de veia cava realizados de 2008 a 2018 na cidade de São Paulo, utilizando o sistema de big data. Resultados Foram analisados 1.324 implantes de filtro de veia cava financiados pelo Sistema Único de Saúde. Identificou-se tendência de aumento da taxa de implantação até 2010 e de redução dos números após esse período. Do total de pacientes, 60,5% eram do sexo feminino; 61,75% tinham menos de 65 anos; e 34,07% possuíam endereço oficial em outra cidade ou estado. A taxa de mortalidade intra-hospitalar foi de 7,4%. Conclusões Observamos aumento das taxas de implante de filtro de veia cava até 2010 e redução das taxas após esse período, o que coincide com o ano em que a organização norte-americana Food and Drug Administration publicou uma recomendação para melhor avaliar as indicações de filtros.

Successful Left Atrial Appendage Closure with Watchman Device Implantation in Two Patients with Inferior Vena Cava Filters

Percutaneous procedures through femoral access in patients with inferior vena cava (IVC) filter may be at risk of complications. We evaluated the feasibility and safety of left atrial appendage closure (LAAC) through femoral access in patients previously implanted with IVC filter. We described the WatchmanTM device implantation in two patients with formal contraindication for oral anticoagulation. First patient had a GreenfieldTM filter and the second one an OpteaseTM filter, and in this patient an attempt to withdrawal the filter immediately before the LAAC procedure failed. A femoral approach was performed in both patients using a 14 Fr sheath. Before crossing IVC filters, venographies did not detect any thrombus. All steps of IVC filter crossing were performed under fluoroscopic guidance. No immediate or intrahospital complications related to the procedure occurred. Herein, we presented two cases of successful LAAC closure with Watchman device in patients with two different kinds of IVC filters.

Filtro de Veia Cava Inferior: Características Clínicas e Prognósticas de Pacientes Oncológicos do INCA / Placement of Inferior Vena Cava Filter: Clinical and Prognostic Characteristics of Cancer Patients at INCA

Introdução: O tromboembolismo venoso é uma condição potencialmente fatal e frequente no paciente oncológico. Muitas vezes, a anticoagulação é inviável, e a colocação do filtro de veia cava (FVC) torna-se uma opção. A indicação clínica, entretanto, é controversa e gera alto custo. Objetivo: Descrever as características demográficas, clínicas e epidemiológicas dos pacientes com colocação de FVC e seu impacto na sobrevida global. Método: Estudo de coorte retrospectiva com pacientes em tratamento oncológico no INCA, que tiveram FVC implantado de janeiro/2015 até abril/2017. Na análise de sobrevida global em cinco anos, foram considerados o tempo entre o diagnóstico de câncer e o óbito por qualquer causa. Realizaram-se análise descritiva, estimativas de sobrevida (Kaplan-Meier) e regressão de Cox. Resultados: Foram incluídos 74 pacientes com média de idade 54 (+-15) anos. Em sua maioria, apresentavam tumores ginecológicos (52,7%) e digestivos (20,3%). O tempo mediano entre o diagnóstico de câncer e a colocação do FVC foi de 3,48 meses (0-203). No seguimento, foram observados 40 óbitos (54,1%) com mediana de tempo de 25 meses (IC 95%; 1,76-47,32). Na análise ajustada, verificou-se risco 5,63 vezes maior de morrer nos pacientes com colocação do FVC em até seis meses após o diagnóstico de câncer (HR=4,99; IC 95%; 2,20-11,33; p<0,001), e risco 2,47 vezes maior entre aqueles que não fizeram no pré-operatório (HR=2,47; IC 95%; 1,08-5,66; p=0,032). Conclusão: A colocação do FVC foi realizada com maior frequência em pacientes com tumores ginecológicos e em até seis meses após o diagnóstico de câncer foi associada a maior risco de óbito.

Introduction: Venous thromboembolism is a potentially fatal condition and frequent in oncologic patients. Quite often full anticoagulation is unfeasible, and placement of an inferior vena cava (IVC) filter becomes an option. Clinical indication, however, is controversial and expensive. Objective: To describe the demographic, clinical and epidemiological characteristics of oncologic patients submitted to IVC filter placement and their impact on global survival. Method: Retrospective cohort study with patients undergoing cancer treatment at INCA submitted to IVC filter placement from January 2015 to April 2017. Time between cancer diagnoses and death from any cause was considered for the analysis of the global 5-years survival. Descriptive analysis, survival estimates (Kaplan-Meyer) and Cox regression were performed. Results: 74 patients with a mean age of 54 (+15) years were included. Most of them had gynecological (52.7%) and digestive (20.3%) tumors. The median time between cancer diagnosis and IVC filter placement was 3.48 months (0-203). In the follow-up, 40 deaths (54.1%) were observed with a median time of 25 months (95% CI; 1.76 to 47.32). In the adjusted analysis, 5.63 times greater risk of death was verified in patients with IVC filter placement within six months after cancer diagnosis (HR=4.99; 95% CI; 2.20-11.33; p<0.001), and 2.47 times greater risk among those who did not do it at pre-operation (HR=2.47; 95% CI; 1.08-5.66; p=0.032). Conclusion: IVC filter placement was performed more frequently in patients with gynecological tumors and in until six months after cancer diagnosis was associated with increased risk of death.

Introducción: El tromboembolismo venoso es una afección potencialmente mortal y frecuente en pacientes con cáncer. La anticoagulación a menudo no es factible, y la colocación de un filtro de vena cava (FVC) se convierte en una opción. Sin embargo, las indicaciones clínicas son controvertidas y generan un alto costo. Objetivo: Describir las características demográficas, clínicas y epidemiológicas de los pacientes con colocación de CVF y su impacto en la supervivencia general. Método: Estudio de cohorte retrospectivo de pacientes sometidos a tratamiento contra el cáncer en INCA a quienes se les implantó FVC entre enero de 2015 y abril de 2017. En el análisis de la supervivencia general a cinco años, el tiempo transcurrido entre el diagnóstico de cáncer y la muerte cualquier causa Se realizó un análisis descriptivo, estimaciones de supervivencia (Kaplan-Meier) y regresión de Cox. Resultados: Se incluyeron 74 pacientes con una edad media de 54 (+-15) años. La mayoría de ellos tenían tumores ginecológicos (52,7%) y digestivos (20,3%). La mediana del tiempo entre el diagnóstico de cáncer y la colocación de FVC fue de 3,48 meses (0-203). En el período de seguimiento, se observaron 40 muertes (54,1%) con una mediana de tiempo de 25 meses (IC 95%: 1,76 a 47,32). En el análisis ajustado, se observó un riesgo de muerte 5,63 veces mayor en pacientes con colocación de FVC dentro de los seis meses posteriores al diagnóstico de cáncer (HR=4,99; IC 95%: 2,20-11,33; p<0,001) y 2,47 veces mayor riesgo entre aquellos que no lo hicieron antes de la operación (HR=2,47; IC 95%; 1,08-5,66; p=0,032). Conclusión: La colocación de FVC se realizó con mayor frecuencia en pacientes con tumores ginecológicos. La colocación de FVC dentro de los seis meses posteriores al diagnóstico de cáncer se asoció con un mayor riesgo de muerte.

Is routine screening for silent pulmonary embolism justified in patients with deep vein thrombosis? / Existe justificativa para o rastreio de embolia pulmonar silenciosa em pacientes com trombose venosa profunda?

Abstract The incidence of asymptomatic pulmonary embolism (PE) exceeds 70% in patients with deep venous thrombosis (DVT), even in cases of distal deep vein thrombosis. We report the case of a patient with a diagnosis of DVT in the lower left limb associated with asymptomatic PE who presented late symptoms due to this same PE. The absence of acute symptoms and the late onset of symptoms could have provoked doubts about the most appropriate treatment, resulting in unnecessary interventions, if pulmonary embolism had not already been diagnosed with tomography. In the present case, we demonstrate that computed tomography angiography conducted at the time of DVT diagnosis accurately diagnosed PE and prevented any misinterpretation of recurrent DVT in a patient already being medicated, which could have been mistakenly interpreted as demonstrating failure of anticoagulant therapy. Such a situation could lead to unnecessary intervention to fit an inferior vena cava filter. We cannot suggest that a classic medical conduct should be reformulated simply on the basis of a case report. However, we would be remiss not to suggest that well-designed studies should be carried out in the future to assess the need for this examination in the acute phase.

Resumo A ocorrência de embolia pulmonar assintomática em pacientes com trombose venosa profunda tem uma incidência que excede 70%, mesmo nos casos de trombose venosa profunda distal. Relatamos o caso de um paciente com diagnóstico de trombose venosa profunda no membro inferior esquerdo associado a embolia pulmonar assintomática, que apresentou sintomas tardios devido a essa mesma embolia. A ausência de sintomas agudos e o surgimento de sintomas tardios pode suscitar dúvidas quanto ao tratamento mais adequado e resultar em intervenções desnecessárias, se o diagnóstico tomográfico de embolia pulmonar não tiver sido feito anteriormente. No presente caso, demonstramos que uma angiotomografia realizada no momento do diagnóstico de trombose venosa profunda detectou a embolia pulmonar e evitou uma interpretação incorreta de um evento trombótico recorrente na vigência de anticoagulação, o que por engano demonstraria uma falha na terapia anticoagulante. Essa situação pode levar a intervenções desnecessárias, como o implante de filtro de veia cava inferior. Entendemos que apenas um relato de caso não deve mudar uma conduta médica já estabelecida; no entanto, fomenta a discussão e estimula estudos que avaliem a necessidade de um exame diagnóstico pulmonar no momento do diagnóstico de trombose venosa profunda.

An alternative approach to treatment of inferior vena cava filter perforation / Tratamento alternativo para perfuração de veia cava inferior por filtro

Abstract We report a case of inferior vena cava filter perforation immediately after filter implantation, recognized intraoperatively in a patient undergoing laparotomy for resection of locally advanced ovarian cancer. We describe an alternative approach with strut resection, less invasive than filter removal, enabling the device to be maintained and bleeding to be controlled.

Resumo Relatamos um caso de perfuração de veia cava inferior imediatamente após o implante de um filtro. A complicação foi reconhecida no intraoperatório de uma laparotomia para ressecção de um câncer de ovário localmente avançado. Descrevemos uma abordagem alternativa, menos invasiva do que a remoção do filtro, consistindo na ressecção das hastes do dispositivo. Essa abordagem permitiu a manutenção do filtro e o controle efetivo do sangramento.

Effect of different structural parameters of filter rod on mechanical properties of new vena cava filter / 生物医学工程学杂志

The dynamic analysis of the implantation process of a new vena cava filter was carried out by finite element analysis method to reveal the influence of the angle, length, width and thickness of the filter rod on its mechanical properties and the inner wall of the blood vessel. The results showed that the high-stress and high-strain areas of the filter were mainly concentrated in the connection between the filter rod and the filter wire. With the increase of the angle of the filter rod, the maximum equivalent stress and the maximum elastic strain on the filter wall decreased, while the maximum equivalent stress on the vascular wall increased. With the increase of the length of the filter rod, the maximum equivalent stress and strain peak of the filter wall increased, but the maximum equivalent stress of the vessel wall decreased. With the increase of the width and thickness of the filter rod, the maximum equivalent stress of the filter wall, the maximum elastic strain and the maximum equivalent stress of the vessel wall all showed an upward trend. The static safety factor of all filter models was greater than 1, and the structure after implantation was safe and reliable. The results of this study are expected to provide a theoretical basis for the structural optimization and deformation mechanism of the new type vena cava filter.

Incidence of thrombotic events and complications associated to inferior vena cava filters in patients with and without anticoagulation therapy / Incidencia de eventos trombóticos y complicaciones asociadas al uso de filtros de vena cava en pacientes en pacientes con o sin terapia anticoagulante

Abstract Objective: Anticoagulation is the primary management to prevent venous thromboembolism; inferior vena cava filters (IVCFs) provide a mechanical prophylactic alternative when anticoagulation is contraindicated. The aim of this study was to evaluate in IVCF patients, whether the initiation of anticoagulation therapy is associated with decreased rates of recurrent thrombotic events and device-related complications. Methods: This was a retrospective review of patients that underwent insertion of IVCF. Subjects with IVCF were studied in two groups: those initiated on anticoagulation (A) and without anticoagulation (NA). Variables as indications for IVCF, anticoagulation, recurrence of thrombosis, complications, and reinterventions were examined. Results: From April 2007 to March 2014, 54 patients underwent IVCF placement; (61% of females), with mean age of 54 years (standard deviation ± 19). 28 (52%) were initiated on anticoagulation, during a mean follow-up period of 28 months, five experienced recurrent thrombosis and three were on the A group (p=0.5); when comparing patients that developed post-thrombotic syndrome, seven were in the A group and seven in the NA. Two patients with IVC rupture were in the A group (p=0.5), and the only case of IVCF migration occurred in the A group. 11 (20%) patients died from comorbidities nonrelated to the device or procedure (four in the A cohort). Conclusions: Patients with IVCF on anticoagulation have equivalent rates of thrombotic events and device-related complications than those patients NA.

Resumen Objetivo: La anticoagulación es la terapia de elección para la prevención de tromboembolismo venoso; los filtros de vena cava inferior (FVCI) proveen una alternativa mecánica profiláctica cuando la anticoagulación está contraindicada. El objetivo de este estudio fue evaluar si la terapia anticoagulante se asocia con una tasa menor de eventos trombóticos recurrentes y complicaciones relacionadas con el dispositivo. Métodos: Los pacientes fueron categorizados en dos grupos: Aquellos a los que se les inicio anticoagulación (A) y aquellos que no (NA). Variables tales como indicación de la colocación del filtro, anticoagulación, recurrencia de trombosis y complicaciones fueron examinadas. Resultados: De abril de 2007 a marzo 2014, a 54 pacientes se les coloco un filtro (61% fueron mujeres), con una media de edad de 54 años [Desviación estándar (DE) ±19. Veintiocho (52%) fueron iniciados en anticoagulación y durante un seguimiento de 28 meses, 5 pacientes experimentaron recurrencia de trombosis, 3 en el grupo A (p=0.5). Al comparar los pacientes que desarrollaron síndrome posflebítico, 7 pertenecieron al grupo A y 7 al grupo NA. Dos pacientes con ruptura de vena cava pertenecieron al grupo A (p=0.5) y el único caso de migración del dispositivo ocurrió en el grupo A. Once (20%) pacientes fallecieron debido a comorbilidades no relacionadas con el dispositivo o el procedimiento. Conclusión: Pacientes con FVCI en anticoagulación tienen tasas de eventos trombóticos y complicaciones asociadas a los dispositivos equivalentes a aquellos pacientes sin anticoagulación.

Hemodynamic analysis of a new retrievable vena cava filter / 生物医学工程学杂志

Vena cava filter is a filter device designed to prevent pulmonary embolism caused by thrombus detached from lower limbs and pelvis. A new retrievable vena cava filter was designed in this study. To evaluate hemodynamic performance and thrombus capture efficiency after transplanting vena cava filter, numerical simulation of computational fluid dynamics was used to simulate hemodynamics and compare it with the commercialized Denali and Aegisy filters, and in vitro experimental test was performed to compare the thrombus capture effect. In this paper, the two-phase flow model of computational fluid dynamics software was used to analyze the outlet blood flow velocity, inlet-outlet pressure difference, wall shear stress on the wall of the filter, the area ratio of the high and low wall shear stress area and thrombus capture efficiency when the thrombus diameter was 5 mm, 10 mm, 15 mm and thrombus content was 10%, 20%, 30%, respectively. Meanwhile, the thrombus capture effects of the above three filters were also compared and evaluated by in vitro experimental data. The results showed that the Denali filter has minimal interference to blood flow after implantation, but has the worst capture effect on 5 mm small diameter thrombus; the Aegisy filter has the best effect on the trapping of thrombus with different diameters and concentrations, but the low wall shear stress area ratio is the largest; the new filter designed in this study has a good filtering and capture efficiency on small-diameter thrombus, and the area ratio of low wall shear stress which is prone to thrombosis is small. The low wall shear stress area of the Denali and Aegisy filters is relatively large, and the risk of thrombosis is high. Based on the above results, it is expected that the new vena cava filter designed in this paper can provide a reference for the design and clinical selection of new filters.

Surgical Removal of the Inferior Vena Cava Filter Using Minimal Cavotomy: A Case Report

The use of retrievable inferior vena cava (IVC) filters has markedly increased in the recent years. However, the failure rate for the retrieval of the IVC filters using the endovascular method is reported to be up to 19%. Open surgical removal of the IVC filters is technically challenging and may require longitudinal cavotomy, clamping, and repair of the IVC. Here, we present a case of successful open surgical removal of the IVC filter using minimal cavotomy. This technique is an effective method after a failed endovascular removal attempt.

Filtros de vena cava para prevenir a tiempo / Vena cava filters for timely prevention

Introducción: Los filtros de vena cava son dispositivos metálicos diseñados especialmente para ser colocados en la vena cava inferior, ante el riesgo de tromboembolismo pulmonar por trombosis venosa profunda. Objetivo: Mostrar una actualización de las características de los filtros de vena cava y su colocación. Métodos: Revisión bibliográfica realizada entre 2010-2016 en las bases de datos: Medline, Cochrane Library, Lilacs, así como en el metabuscador Google. Se consultaron estudios de cohorte, prospectivos, retrospectivos, clínicos, epidemiológicos, metaanálisis, revisiones bibliográficas y ensayos clínicos. Resultados: se describieron y usaron por primera vez en 1967 en Estados Unidos de Norteamérica. Estos dispositivos se implementan por vía percutánea y producen una interrupción mecánica parcial del flujo sanguíneo de la vena cava inferior. Actualmente, existen filtros de tres tipos: permanentes, temporales y mixtos. El factor más importante de cualquier filtro es el grado de atrapamiento de los coágulos, grado de acceso a la vena cava y de oclusión, riesgo de embolización, grado de integridad mecánica y facilidad para su colocación. Las complicaciones de los filtros pueden ocurrir de modo inmediato o a largo plazo, con un promedio de 0,3 por ciento de complicaciones mayores y menos de 0,2 por ciento de los pacientes fallecen como resultado de la colocación del filtro. Conclusiones: A pesar de su efectividad demostrada, no existen publicaciones en Cuba que avalen su uso. Por su importancia y capacidad resolutiva se sugiere que esta técnica debe comenzarse a aplicar, de manera habitual, en los centros hospitalarios de atención secundaria y terciaria del país(AU)

Introduction: Vena cava filters are special metallic devices designed specially to be placed in the inferior cava vein in view of imminent risk of pulmonary tromboembolism by deep venous thrombosis. Objective: To update the state of vena cava filters and their placement. Methods: A bibliographic review was carried out in the years 2010 to 2016 in Medline, Cochrane Library and Lilacs data bases, as well as in Google search engine. There were consulted cohort, prospective, retrospective, clinical and epidemiological studies, meta-analysis, bibliographic reviews and clinical trials. Results: Vena cava filters were described and used for the first time in 1967 in the United States of America. The filters can be placed percutaneously and produce a partial mechanical disruption of the inferior cava vein flow. There are 3 kinds of filters in the market: permanent, temporal and mixed. The key factors of a filter are clot trapping capacity, access to the vena cava and occlusion capacity; also embolization, mechanical integrity grade, and placement feasibility. Complications by the filter may occur immediately or in a long term, with an average of 0, 3 percent in major complications, and less than 0,2 percent of mortality rate due to the placement of the filter. Conclusion: In spite of its proven benefits, there is not existence in Cuba of publications that guarantee its use. Because of its importance and resolvent capacity, it is suggested that this technique should start to be usually used in secondary and tertiary level hospitals in Cuba(AU)

Deep Vein Thrombosis Due to Compression of Huge Hepatic Cyst Successfully Treated by Inferior Vena Cava Filter and Cyst Drainage / 대한소화기학회지

An 88-year-old woman complained of right quadrant abdominal pain and severe edema in both legs. She had a history of pulmonary embolism one month ago. Abdomen CT showed a huge hepatic cyst compressing the intrahepatic portion of the inferior vena cava (IVC). The venogram CT showed multifocal thrombosis in the iliocaval and both lower extremity veins. Percutaneous hepatic cyst drainage was carried out. Fluid analysis presented leukocytosis, which suggested an infected hepatic cyst. To prevent secondary pulmonary thromboembolism, an IVC filter was inserted before catheter drainage for the hepatic cyst. One week later, abdominal pain was relieved. Then, sclerotherapy for the remnant hepatic cyst was performed by ethanol. Follow-up CT showed an increased amount of thrombosis in the iliocaval and left calf vein, but the IVC filter prevented another thromboembolic event successfully. The patient started dabigatran, a new oral anticoagulant, and compression stockings were applied to both legs. After one month, no visible thrombosis in the pelvis or either extremity was detected in abdominal CT. This case suggests that a huge hepatic cyst, especially with infection, should be considered as a possible cause of deep vein thrombosis if no other risk factors for thromboembolism exist.

Clinical Outcomes of a Preoperative Inferior Vena Cava Filter in Acute Venous Thromboembolism Patients Undergoing Abdominal-Pelvic Cancer or Orthopedic Surgery

PURPOSE: Surgery is the most common risk factor for pulmonary embolism (PE) in patients with a recent venous thromboembolism (VTE). This study reviewed clinical outcomes of preoperative inferior vena cava filter (IVCF) use in patients with acute VTE during abdominal-pelvic cancer or lower extremity orthopedic surgeries. MATERIALS AND METHODS: We retrospectively analyzed 122 patients with a recent VTE who underwent IVCF replacement prior to abdominal-pelvic cancer or lower extremity orthopedic surgery conducted between January 2010 and December 2016. Demographics, clinical characteristics, postoperative IVCF status, risk factors for a captured thrombus, and clinical outcomes were collected for these subjects. RESULTS: Among the 122 study patients who were diagnosed with acute VTE in the prior 3 months and underwent preoperative IVCF replacement, 70 patients (57.4%) received abdominal-pelvic cancer surgery and 52 (42.6%) underwent lower extremity orthopedic surgery. There were no perioperative complications associated with IVCF in the study population and no cases of symptomatic PE postoperatively. A captured thrombus in the filter was identified postoperatively in 16 patients (13.1%). Logistic regression analysis indicated that postoperative anticoagulation within 48 hours significantly reduced the risk of a captured thrombus (odds ratio [OR], 0.28; 95% confidence interval [CI], 0.08–0.94; P=0.032). CONCLUSION: A captured thrombus in preoperative IVCF was identified postoperatively in 16 patients (13.1%). Postoperative anticoagulation within 48 hours reduces the risk of captured thrombus in these cases.

Inferior vena cava filters in pulmonary embolism: A historic controversy / Filtros de vena cava inferior en tromboembolia pulmonar: Una controversia histórica

Abstract: Objective: Rationale for non-routine use of inferior venous cava filters (IVCF) in pulmonary embolism (PE) patients. Methods: Thrombosis mechanisms involved with IVCF placement and removal, the blood-contacting medical device inducing clotting, and the inorganic polyphosphate in the contact activation pathway were analyzed. In addition, we analyzed clinical evidence from randomized trials, including patients with and without cancer. Furthermore, we estimated the absolute risk reduction (ARR), the relative risk reduction (RRR), and the number needed to treat (NNT) based on the results of each study using a frequency table. Finally, we analyzed the outcome of our PE patients that were submitted to thrombolysis with short and long term follow-up. Results: IVCF induces thrombosis by several mechanisms including placement and removal, rapid protein adsorption, and simultaneous surface-induced activation via the contact activation pathway. Also, inorganic polyphosphate has an important role as a procoagulant, reversing the effect of anticoagulants. Randomized control trials included 904 cancer and non-cancer PE patients. In terms of ARR, RRR, and NNT, there is no evidence for routine use of IVCF. In 290 patients with proved PE, extensive thrombotic burden and right ventricular dysfunction under thrombolysis and oral anticoagulation, we observed a favorable outcome in a short- and long-term follow-up; additionally, IVCF was only used in 5% of these patients. Conclusion: Considering the complex mechanisms of thrombosis related with IVCF, the evidence from randomized control trials and ARR, RRR, and NNT obtained from venous thromboembolism patients with and without cancer, non-routine use of IVCF is recommended.

Resumen: Objetivo: Racionalidad para no utilizar en forma rutinaria filtros de vena cava inferior (FVCI) en pacientes con tromboembolia pulmonar (TEP). Métodos: Analizamos mecanismos de trombosis relacionados con la colocación o retiro de estos dispositivos médicos, incluyendo la importancia del polifosfato inorgánico en la vía de activación de contacto. Analizamos evidencia clínica de estudios aleatorizados controlados en pacientes con y sin cáncer. Mediante tablas de frecuencia estimamos de cada estudio reducción del riesgo absoluto (RRA) y relativo (RRR) y el número necesario a tratar (NNT). Finalmente, examinamos la evolución de nuestros pacientes con TEP llevados a trombolisis con seguimientos a corto y largo plazo. Resultados: FVCI inducen trombosis por diferentes mecanismos: colocación y retiro, adsorción rápida de proteínas y activación de superficie inducida en la vía de activación de contacto. El polifosfato inorgánico es un procoagulante importante para la anticoagulación. Estudios aleatorizados controlados incluyeron 904 pacientes con TEP con y sin cáncer. En términos de RRA, RRR y NNT no existe evidencia para el uso rutinario. En 290 pacientes con TEP probada, importante carga de trombo y disfunción del ventrículo derecho llevados a trombolisis y anticoagulación observamos una evolución favorable en seguimientos a corto y largo plazo. En estos pacientes los FVCI se utilizaron solo en el 5%. Conclusión: Considerando los mecanismos complejos de trombosis relacionados con los FVCI, la evidencia obtenida de los estudios aleatorizados y controlados, así como la RRA, RRR y NNT en pacientes con tromboembolismo venoso con y sin cáncer, no recomendamos el uso rutinario de FVCI.

Should We Remove the Retrievable Cook Celect Inferior Vena Cava Filter? Eight Years of Experience at a Single Center

BACKGROUND: The inferior vena cava filter (IVCF) is very effective for preventing pulmonary embolism in patients who cannot undergo anticoagulation therapy. However, if a filter is placed in the body permanently, it may lead to other complications. METHODS: A retrospective study was performed of 159 patients who underwent retrievable Cook Celect IVCF implantation between January 2007 and April 2015 at a single center. Baseline characteristics, indications, and complications caused by the filter were investigated. RESULTS: The most common underlying disease of patients receiving the filter was cancer (24.3%). Venous thrombolysis or thrombectomy was the most common indication for IVCF insertion in this study (47.2%). The most common complication was inferior vena cava penetration, the risk of which increased the longer the filter remained in the body (p=0.032, Exp(B)=1.004). CONCLUSION: If the patient is able to retry anticoagulation therapy and the filter is no longer needed, the filter should be removed, even if a long time has elapsed since implantation. If the filter cannot be removed, it is recommended that follow-up computed tomography be performed regularly to monitor the progress of venous thromboembolisms as well as any filter-related complications.

Extravascular Migration of a Fractured Inferior Vena Cava Filter Strut

A 20-year-old man presented with a femur fracture and epidural hemorrhage (EDH) following a fall. One month after fracture surgery, swelling developed in both legs, and he was diagnosed as having a deep-vein thrombosis and pulmonary embolism. A retrievable inferior vena cava filter (IVCF) was inserted, because EDH is a contraindication to anticoagulants. Four months later, he complained of abdominal pain, and a computed tomography scan showed a fractured IVCF strut. After percutaneous removal failed 3 times, the IVCF was surgically removed by orthopedists using a portable image intensifier without cardiopulmonary bypass.

Pathological Significance of Tissue Trapped in Retrieved OptEase Vena Cava Filter at 18th Day after Installation in Patient with Deep Vein Thrombosis

The retrievable type of inferior vena cava filter has been widely used to prevent pulmonary thromboembolism in patients with deep vein thrombosis and contraindication of anticoagulation. Physicians make considerable efforts to remove the filter according to the manufacturer and US Food and Drug Administration safety advisory recommendation. However, forced filter retrieval might cause vascular injury within 3 weeks. Herein, we report pathologic and angiographic findings to suggest filter associated vascular injury during forced retrieval just within recommended period in a patient with deep vein thrombosis.

In vivo evaluation of a new vena cava filter / Avaliação in vivo de um novo filtro de veia cava

Background Pulmonary embolism is an important cause of cardiovascular death. Inferior vena cava filters have been shown to be effective for prevention of this condition. Objectives To determine the safety, performance and efficacy of a new inferior vena cava filter in an ovine model. Methods BKone1 filters are self-centering with over-the-wire deployment, have three filtering regions and are made from nickel-titanium alloy. Eight of these filters were implanted in 8 sheep. The sheep were divided into 4 groups of two animals (A and B) and the number of clots injected differed by group. Two clots were injected in group 2, four in group 3, eight in group 4 and zero clots in group 1. A animals underwent euthanasia soon after the procedure and B animals were observed for 30 days and then euthanized after a control cavography. All inferior vena cavas were processed for histological examination. Clots were prepared in a metal mold, sectioned and then radiopaque markers were inserted. Clot capture was analyzed by identifying the radiopaque marker on fluoroscopy. Results No clot migration was observed during follow-up. Control cavographies showed patent inferior vena cavas. Pathological examination indicated little inflammatory tissue response. All clots were captured in the condition with 2 clots, only one clot was missed in the group injected with 4 clots and in the condition of 8 clots, they were partly captured. Conclusions The filters were deployed safely. There was a reduction in efficacy as the number of blood clots increased.

Contexto Embolia pulmonar é uma importante causa de morte cardiovascular. Filtros de veia cava inferior têm se mostrado efetivos na sua prevenção. Objetivos Determinar a segurança, o desempenho e a eficácia de um novo filtro de veia cava inferior em estudo experimental utilizando modelos ovinos. Métodos Filtros BKone1 são autocentrantes, over-the-wire (OTW), compostos por três regiões de filtragem e construídos em liga de níquel-titânio. Oito filtros foram implantados em oito ovelhas. As ovelhas foram divididas em quatro grupos, de acordo com o número de êmbolos injetados, com dois animais em cada grupo (A e B). Foram injetados dois êmbolos no grupo 2, quatro no grupo 3, oito no grupo 4 e nenhum êmbolo no grupo 1. Os animais denominados A foram submetidos a eutanásia logo após o procedimento e os animais B foram observados por 30 dias, sendo submetidos a eutanásia após a realização de uma cavografia de controle. Após a eutanásia, todos os animais foram submetidos a explante do segmento de veia cava inferior contendo o filtro para análise anatomopatológica. Os êmbolos foram preparados em molde metálico e seccionados, adicionando-se marcadores radiopacos. A retenção dos êmbolos foi constatada através da identificação da marca radiopaca na seção de captura do filtro, via fluoroscopia. Resultados Não foi observada migração do filtro após o período de 30 dias. As cavografias de controle mostraram perviedade das veias cava inferior. Os resultados dos exames anatomopatológicos indicaram pouca resposta inflamatória dos tecidos. Os êmbolos foram capturados totalmente na condição com dois êmbolos, apenas um êmbolo não foi capturado no grupo com quatro êmbolos e na condição de oito êmbolos, eles foram parcialmente capturados. Conclusões Os filtros foram entregues com segurança. Há uma queda na eficácia de captura com o aumento da quantidade de êmbolos.

Uso de cânula venovenosa com duplo-lúmen para oxigenação por membrana extracorpórea em paciente com síndrome de angústia respiratória aguda com prévia inserção de filtro na veia cava inferior: relato de caso / Use of a dual lumen cannula for venovenous extra corporeal membrane oxygenation in a patient with acute respiratory distress syndrome and a previously inserted inferior vena cava filter: a case report

RESUMO A oxigenação por membrana extracorpórea é utilizada em casos de hipoxemia refratária em diversas condições clínicas. Pacientes vítimas de traumatismo torácico geralmente desenvolvem síndrome da angústia respiratória aguda. Em razão do elevado risco de sangramentos, as complicações trombóticas que se apresentam neste contexto são particularmente difíceis de tratar e, geralmente, demandam a inserção de um filtro na veia cava inferior, com a finalidade de prevenir a migração de êmbolos oriundos das veias distais para a circulação pulmonar. Neste artigo, apresentamos o caso de um paciente com traumatismo torácico, que apresentou grave síndrome de angústia respiratória aguda, com necessidade de utilizar oxigenação por membrana extracorpórea aplicada por meio da introdução de uma cânula com duplo-lúmen na veia jugular interna direita. Este procedimento foi realizado tendo em vista a prévia inserção de um filtro na veia cava inferior, por conta da ocorrência de trombose venosa profunda em ambas as panturrilhas.

ABSTRACT Extracorporeal membrane oxygenation is used in refractory hypoxemia in many clinical settings. Thoracic trauma patients usually develop acute respiratory distress syndrome. Due to high risk of bleeding, thrombotic complications present in this context are particularly difficult to manage and usually require insertion of an inferior vena cava filter to prevent embolism from the distal veins to the pulmonary circulation. Here, we present a case of a thoracic trauma patient with severe acute respiratory distress syndrome requiring venovenous extracorporeal membrane oxygenation via a right internal jugular double lumen cannula due to a previously inserted inferior vena cava filter caused by distal bilateral calf muscle vein deep vein thrombosis.

Delayed Presentation of Endovenous Heat-Induced Thrombosis Treated by Thrombolysis and Subsequent Open Thrombectomy

Although endovenous heat-induced thrombosis (EHIT) is frequently reported after endovenous laser ablation (EVLA), the incidence and timing of occurrence of EHIT are not fully understood. We present a case of EHIT successfully treated with a combination of surgical and endovascular treatments. A 57-year-old woman, two months post bilateral EVLA, presented with a swollen leg. Deep vein thrombosis was diagnosed by Doppler ultrasonography and computerized tomographic venography. We treated the patient with catheter-directed thrombolysis with urokinase after insertion of an inferior vena cava filter. After thrombolytic treatment, we performed surgical venous thrombectomy, due to the presence of a large thrombus in the femoral vein. During the operation, we found organized old thrombus at the great saphenous vein which connected to the deep femoral vein. From these findings, we confirmed the presence of EHIT despite a long time having passed after EVLA. The patient was placed on anticoagulation therapy with oral rivaroxaban for three months.