Cardiovascular disease and peripheral vascular disease: socioenvironmental aspects and structural analysis of fatigue resistance of a new covered peripheral vascular stent prototype

Submitted by admin tede ([email protected]) on 2019-12-05T18:56:52Z No. of bitstreams: 1 Fabio Augusto Cypreste Oliveira.pdf: 26362413 bytes, checksum: 8dae21d721133eee8c2175ccd466a5ce (MD5)Made available in DSpace on 2019-12-05T18:56:52Z (GMT). No. of bitstreams: 1 Fabio Augusto Cypreste Oliveira.pdf: 26362413 bytes, checksum: 8dae21d721133eee8c2175ccd466a5ce (MD5) Previous issue date: 2019-10-02Peripheral vascular disease, an important component of cardiovascular diseases, represents a considerable cause of death and hospitalization due to chronic disease in Brazil and in the world, causing an overload on health systems and great financial impact. In the last decades, there has been a change in the surgical treatment of peripheral circulatory diseases, with a significant increase in minimally invasive endovascular procedures and in the use of peripheral stents. New intraluminal devices have been developed with structural improvements in order to increase their effectiveness and durability, with the laboratory tests of fatigue resistance being fundamental in this process. The objective of this study was to perform the structural analysis of fatigue resistance of a new model of covered peripheral vascular stent. The evaluation of the prototype was performed by using two methods: in vitro accelerated fatigue test (AFT) and computational analysis using the finite element method (FEM). A total of 6 prototypes analyzed macroscopically and microscopically before and after AFT, as well as computational analysis of the model using Solidworks® and Abaqus® software in its simulation. The prototypes submitted to the accelerated fatigue test were successful in fatigue resistance after a total of 400 million cycles of accelerated fatigue and the computational analysis of the proposed model, after validation, was able to confirm safety and identify the points of greatest stress / strain under simulated conditions of pulsatile arterial flow in stenosed peripheral artery. Based on this work, it is concluded that the studied model of covered peripheral vascular stent presents adequate structural resistance to the analyses performed, in accordance with international standardsA doença vascular periférica, importante componente das doenças cardiovasculares, representa uma considerável causa de óbito e internação por doença crônica no Brasil e no mundo, promovendo uma sobrecarga aos sistemas de saúde e grande impacto financeiro. Nas últimas décadas, houve uma mudança no perfil de tratamento cirúrgico das doenças circulatórias periféricas, com aumento significativo dos procedimentos terapêuticos endovasculares minimamente invasivos e uso dos stents periféricos. Novos dispositivos intraluminais vem sendo desenvolvidos com melhorias estruturais de modo a aumentar sua eficácia e durabilidade, sendo os testes laboratoriais de resistência à fadiga de importância fundamental nesta avaliação. O objetivo deste estudo foi realizar a análise estrutural de resistência a fadiga de um novo modelo de stent vascular periférico recoberto. A avaliação do protótipo foi realizada por meio de dois métodos: teste in vitro de fadiga acelerada (TFA) e análise computacional pelo método de elementos finitos (MEF). Foram analisados macroscopicamente e microscopicamente um total de 6 protótipos antes e após o TFA, além de análise computacional do modelo utilizando os softwares Solidworks® e Abaqus® em sua simulação. Os protótipos submetidos ao teste de fadiga acelerada obtiveram sucesso no quesito resistência à fadiga após um total de 400 milhões de ciclos de fadiga acelerada e a análise computacional do modelo proposto, após sua validação, ratificou sua segurança e identificou os pontos de maior tensão/deformação sob condições simuladas de fluxo arterial pulsátil em artéria periférica estenosada. Com base nesse trabalho, conclui-se que o modelo estudado de stent vascular periférico recoberto apresenta resistência estrutural adequada às análises realizadas, conforme as normas internacionai

Emergency embolization after resection of a laryngeal Schwannoma

Schwannoma is a rare cause of benign tumors of the larynx. The first-choice treatment is surgical resection. The objective of this paper is to report on a rare case of a young female patient who suffered severe intraoperative hemorrhaging during surgical resection of a laryngeal Schwannoma and needed emergency embolization

Emergency embolization after resection of a laryngeal Schwannoma

Schwannoma is a rare cause of benign tumors of the larynx. The first-choice treatment is surgical resection. The objective of this paper is to report on a rare case of a young female patient who suffered severe intraoperative hemorrhaging during surgical resection of a laryngeal Schwannoma and needed emergency embolization

Correction of carotid-jugular traumatic fistula using a bovine pericardial patch

Carotid-jugular fistulae are rare, but habitually cause morbidity and mortality. They are often linked with penetrating trauma, primarily caused by gunshots. This report describes the case of a patient who was the victim of a gunshot wound to the left cervical area, provoking a carotid-jugular arteriovenous fistula and occlusion of the common carotid artery. The fistula was corrected by ligature of the internal jugular vein and arteriorrhaphy of the left common carotid artery with a bovine pericardium patch