Développement de terpolymère électrostrictif P (VDF-TrFE-CTFE) pour applications médicales

In the 21st century, cardiovascular diseases became a major cause of mortality, the first in the entire world, the second in France after cancers. Indeed, cardiovascular risk factors have been increasing significantly over the past decades and this phenomenon is ongoing today. These factors cause atherosclerosis and lead to coronary acute syndrome, heart attacks, cerebrovascular accident, renal insufficiency but also to peripheral arterial disease (PAOD) and arterial aneurysms. First line treatment of atherosclerosis, regardless of arterial territory concerned, is medical treatment. But, if despite best medical treatment, symptoms are important for patients, interventional treatment may be considered. For aneurysms and for PAOD, vascular surgery is possible. Vascular surgery can be divided into two categories: conventional open repair (COR) and endovascular techniques (ET). During the last ten years, ET became the first line treatment for most arterial injuries. ET has become the first line treatment because it allows a considerable reduction in surgical morbi-mortality and a great reduction in health costs.Au XXIe siècle, les maladies cardiovasculaires sont devenues une cause majeure de mortalité, la première au monde, la deuxième en France après les cancers. En effet, les facteurs de risque cardiovasculaires ont augmenté de façon significative au cours des dernières décennies et ce phénomène se poursuit aujourd'hui. Ces facteurs sont responsables du développement de l’athérosclérose et mènent à des syndromes coronariens aigus, des crises cardiaques, des accidents cérébrovasculaires, des insuffisances rénales mais également à des maladies artérielles périphériques et à des anévrysmes artériels. Le traitement de première ligne de l'athérosclérose, indépendamment du territoire artériel concerné, est le traitement médical. Mais, si malgré le meilleur traitement médical, les symptômes sont importants pour les patients, le traitement interventionnel peut être considéré. Pour les anévrismes et pour la maladie artérielle périphérique, la chirurgie vasculaire est possible. La chirurgie vasculaire peut être divisée en deux catégories : la chirurgie ouverte conventionnelle et les techniques endovasculaires. Au cours des dix dernières années, les techniques endovasculaires sont devenues le traitement de première ligne pour la plupart de ces lésions artérielles. Elles sont devenues le traitement de première ligne, car elles permettent une réduction considérable de la morbi-mortalité chirurgicale et une grande réduction des coûts de santé

Les résultats à court et long terme des pontages aortobifémoraux pour maladie occlusive sont-ils TASC dépendants ?

LYON1-BU Santé (693882101) / SudocSudocFranceF

Digital model of radiocephalic arteriovenous fistula for decision support and improvement of maturation

International audienceObjectives: The native arteriovenous fistula (AVF) is the recommended first intention vascular access in dialysis patients. This non-physiological surgical construction implies many anatomical and hemodynamic parameters. Radiocephalic AVFs are preferred due to a low rate of long-term complications. The early rates of thrombosis and failure of maturation of the distal AVFs remain high, between 20 and 50%. The aim of this work was to obtain a faithful digital model simulating the flow of a radiocephalic AVF to guide the surgeon in the choice and the technical realization of AFVs in order to improve maturation. Material and methods: We created a digital model simulating the flow using the Foam-extend 4.0 software with resolution by PISO algorithms (procedure of pressure to velocity calculation for the analysis of nonstable compressible fluid). We then analyzed the influence of five parameters on maturation: artery and vein diameters, distance between the two vessels, diameter and angle of the anastomosis. We evaluated the development of myointimal hyperplasia in the anastomotic and postanastomotic zones by studying the wall shear-stress and the oscillating shear-stress. We finally compared the results of our simulation with the data of five patients. Results: Our digital model allowed to predict the flow of an AVF according to the diameters and distances of the vessels and to advise against radio-cephalic AVF when the parameters are too unfavorable (too much loss of energy in the peri-anastomotic zone). Furthermore, the anastomotic angle was the parameter having the most influence on the maturation and the development of myointimal hyperplasia. The comparison between simulation and clinical data obtained with the 1month duplex showed a good correlation in terms of flow and development of stenoses in the five cases. Conclusion: Our digital model is reproducible and valid with a good correlation with the clinical cases. It could give recommendations to the surgeon on chances of maturation of an AVF according to the preoperative anatomical parameters and the best anastomotic angle to have a good maturation. This model should now be tested on a larger number of clinical cases

Effects on Mortality and Cardiovascular Events of Adherence to Guideline-Recommended Therapy 4 Years after Lower Extremity Arterial Revascularization

International audienc

How Admission to a Vascular Surgery Department Improves Medical Treatment in Patients with Lower Extremity Peripheral Arterial Disease

International audienc

A Computational Analysis of the Influence of Anastomosis Angle on Stenosis-Prone Locations during Radio-Cephalic Arteriovenous Fistula Maturation

International audienceIn dialysis treatment, the radio-cephalic arteriovenous fistula (RCAVF) is a commonly used fistula, yet its low maturation rate remains a challenge. To enhance surgical outcomes, the relationship between stenosis-prone locations and RCAVF anastomosis angle is studied during maturation by developing two sets of RCAVF models for early (nonmature) and mature RCAVFs at five anastomosis angles. The impact of hemodynamics and wall shear stress (WSS) is examined to determine optimal anastomotic angles. Results indicate that acute angles produce more physiological WSS distributions and fewer disturbed regions, with early stenosis-prone regions located near the anastomosis that shift to the bending venous segment during remodeling. A pilot study comparing clinical and numerical results is conducted for validation