Search results for "Blood vessel prosthesis"
showing 10 items of 140 documents
In Vivo Functional Evaluation of Tissue-Engineered Vascular Grafts Fabricated Using Human Adipose-Derived Stem Cells from High Cardiovascular Risk Po…
2016
Many preclinical evaluations of autologous small-diameter tissue-engineered vascular grafts (TEVGs) utilize cells from healthy humans or animals. However, these models hold minimal relevance for clinical translation, as the main targeted demographic is patients at high cardiovascular risk such as individuals with diabetes mellitus or the elderly. Stem cells such as adipose-derived mesenchymal stem cells (AD-MSCs) represent a clinically ideal cell type for TEVGs, as these can be easily and plentifully harvested and offer regenerative potential. To understand whether AD-MSCs sourced from diabetic and elderly donors are as effective as those from young nondiabetics (i.e., healthy) in the conte…
Wet Chemistry and Peptide Immobilization on Polytetrafluoroethylene for Improved Cell-adhesion
2016
Endowing materials surface with cell-adhesive properties is a common strategy in biomaterial research and tissue engineering. This is particularly interesting for already approved polymers that have a long standing use in medicine because these materials are well characterized and legal issues associated with the introduction of newly synthesized polymers may be avoided. Polytetrafluoroethylene (PTFE) is one of the most frequently employed materials for the manufacturing of vascular grafts but the polymer lacks cell adhesion promoting features. Endothelialization, i.e., complete coverage of the grafts inner surface with a confluent layer of endothelial cells is regarded key to optimal perfo…
CT angiography for the assessment of EVAR complications : a pictorial review
2022
Aortic aneurysm; Blood vessel prosthesis implantation; Endovascular procedures Aneurisma aórtico; Implantación de prótesis de vasos sanguíneos; Procedimientos endovasculares Aneurisma aòrtic; Implantació de pròtesis de vasos sanguinis; Procediments endovasculars Endovascular aneurysm repair (EVAR) is a minimally invasive treatment proposed as an alternative to open repair in patients with abdominal aortic aneurysms. EVAR consists in a stent-graft placement within the aorta in order to exclude the aneurysm from arterial circulation and reduce the risk of rupture. Knowledge of the various types of devices is mandatory because some stents/grafts are more frequently associated with complication…
Periscopes, chimneys, sandwich and VORTEC to facilitate abdominal and thoracoabdominal aortic aneurysm repair
2012
The VORTEC (VIABAHN open revascularization technique) and the chimney graft technique are tools with which to maintain or restore blood flow to the aortic branches and can be used intentionally or as a bailout procedure in open surgery or endovascular procedures. VORTEC is a stent graft-based vascular connection technique that achieves end-to-end anastomosis configuration; it is especially useful when the traditional suture technique proves (can be) cumbersome. It is also a speedy tool with virtually no blood flow interruption and no anastomotic bleeding, and patency rates compare favorably with sutured anastomosis. The chimney/periscope, as well as the sandwich graft technique (CHIMPES), i…
Evaluation of the stromal vascular fraction of adipose tissue as the basis for a stem cell-based tissue-engineered vascular graft
2017
Abstract Objective One of the rate-limiting barriers within the field of vascular tissue engineering is the lengthy fabrication time associated with expanding appropriate cell types in culture. One particularly attractive cell type for this purpose is the adipose-derived mesenchymal stem cell (AD-MSC), which is abundant and easily harvested from liposuction procedures. Even this cell type has its drawbacks, however, including the required culture period for expansion, which could pose risks of cellular transformation or contamination. Eliminating culture entirely would be ideal to avoid these concerns. In this study, we used the raw population of cells obtained after digestion of human lipo…
Biomechanical implications of excessive endograft protrusion into the aortic arch after thoracic endovascular repair
2015
Endografts placed in the aorta for thoracic endovascular aortic repair (TEVAR) may determine malappositioning to the lesser curvature of the aortic wall, thus resulting in a devastating complication known as endograft collapse. This premature device failure commonly occurs in young individuals after TEVAR for traumatic aortic injuries as a result of applications outside the physical conditions for which the endograft was designed. In this study, an experimentally-calibrated fluid-structure interaction (FSI) model was developed to assess the hemodynamic and stress/strain distributions acting on the excessive protrusion extension (PE) of endografts deployed in four young patients underwent TE…
Questionable Value of Adjuvant Arteriovenous Fistula in Pedal Bypass at High Risk for Early Failure
2007
Results of an adjuvant arteriovenous fistula (AVF) in pedal bypass surgery in the presence of poor status of the recipient artery, severely impaired intraoperative runoff, or revision for early failure and flow restitution were analyzed in a retrospective study. From January 1998 to December 2006, 24 adjuvant AVFs were constructed in autologous vein or composite pedal bypasses with low intraoperative bypass flow, poor status of the pedal artery, or during successful early bypass revision to prevent graft failure. All infrainguinal bypass operations were registered in a computerized database and prospectively followed. Pedal bypasses with adjunctive AVF were reviewed for fistula function, gr…
Symptomatic Deep Femoral Artery Pseudoaneurysm Endovascular Exclusion. Case Report and Literature Review.
2017
Deep femoral artery pseudoaneurysms (DFAPs) are rare and generally occur after penetrating trauma or surgical procedures. A 36-year-old obese man presented with pain in correspondence of the anterior-lateral thigh after 6 months from gunshot wound. Duplex and computed tomography (CT) showed a bilobed right DFAP (maximal diameter 12.9 cm). The patient was managed urgently, under local anesthesia, by placement in the distal DFA of a Viabahn 8 Ã 100-mm stent graft (W L Gore & Associates, Inc). The postoperative course was uneventful, and the 24-month CT showed regular stent-graft patency and 20-mm DFAP shrinkage. The literature review reported 8 cases of DFAPs; of these 6 were managed by endo…
Descriptive and follow-up study of patients treated surgically for abdominal aortic aneurysm at tertiary hospitals in Spain.
2019
BACKGROUND The aim of this study was to assess potential variability in the clinical characteristics and treatment of patients undergoing elective surgery for abdominal aortic aneurysm (AAA) across five hospitals in Spain. METHODS Multicenter, retrospective cohort study of patients diagnosed with AAA and treated with open surgical repair (OSR) or endovascular aneurysm repair (EVAR). We evaluated clinical and demographic variables, including comorbidity (Charlson Comorbidity Index [CCI]); anatomic characteristics; surgical risk (ASA Score); aneurysm characteristics; and in-hospital and overall mortality. All patients were followed for three years. RESULTS A total of 186 patients were include…
Multiple periscope and chimney grafts to treat ruptured thoracoabdominal and pararenal aortic aneurysms
2011
Purpose: To report midterm outcomes after urgent endovascular repair of ruptured pararenal or thoracoabdominal aortic aneurysms using multiple periscope and chimney grafts to preserve renovisceral branch perfusion and facilitate aneurysm exclusion. Methods: Nine consecutive men (mean age 72614 years, range 40–88) presenting with ruptured thoracoabdominal (n56), pararenal (n52), or infrarenal (n51) aortic aneurysm underwent urgent endovascular repair with at least 1 periscope graft delivered via a transfemoral access; chimney grafts were installed from an axillary access. In all, 17 periscope and 7 chimney grafts were used to reperfuse 11 renal and 13 visceral arteries in the 9 patients. The…