In vivo evaluation of a new vena cava filter

• Published in: Jornal vascular brasileiro 2016-04, Vol.15 (2), p.99-105
• Main Authors: Galego, Gilberto do Nascimento, Silveira, Pierre Galvagni, Broering, Júlia Jochen, Eli, Eduardo da Silva, Corbellini, Marcelo Peixer, Oliveira Junior, Amir Antônio Martins de
• Format: Article
• Language: English
• Subjects: CARDIAC & CARDIOVASCULAR SYSTEMS; embolia pulmonar; filtro de veia cava; modelo in vivo; modelo ovino; Original; PERIPHERAL VASCULAR DISEASE; SURGERY
• ISSN: 1677-5449; 1677-7301; 1677-7301
• DOI: 10.1590/1677-5449.006915

Abstract 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. Resumo 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