Search results for " Aorta"
showing 10 items of 185 documents
Ascending Aorta Resection and End-to-End Anastomosis: Redistribution of Wall Shear Stress Induced by a Bioprosthetic Heart Valve
2020
Although aortic resection and end-to-end anastomosis are applied to repair ascending aortic aneurysm, there is a lack of information on the late risk of post-operative complications, such as aortic dissection and aneurysmal re-dilatation. It is recognized that altered hemodynamic forces exerted on an aortic wall play an important role on dissection and aneurysm formation. We present a case in which the hemodynamic forces were investigated prior and after repair of an ascending aorta treated by resection with end-to-end anastomosis and a bioprosthetic heart valve. Post-operative wall shear stress was redistributed uniformly along the vessel circumference, and this may suggest a reduced risk …
A clampless and sutureless aortic anastomosis technique using an endograft connector for aortoiliac occlusive disease in which the aorta cannot be cl…
2012
Bypass surgery in aortoiliac or aortofemoral occlusive disease can be technically demanding and hazardous due to huge calcifications and/or patient co-morbidities. We report about mid-term results of a telescoping sutureless aortic anastomosis technique using endografts as connectors to address such challenging situations. This is a single-center experience (2004–2011) in seven patients (63 ± 6 years) requiring aortoiliac (three) or aortofemoral (four) bypass surgery. In six cases, an aortic stent graft was telescoped into the infrarenal aorta and partly deployed within the aorta and partly outside the aorta. In the first case, a bifurcated stent graft was deployed and the iliac legs were p…
Tips and tricks to make the ascending aorta accessible to EVAR
2012
The ascending aorta is gaining increasing interest for endovascular specialists, as it opens the door to a potentially better way to treat aortic arch pathologies. Landing safely a stentgraft into the ascending aorta allows downgrading significantly the invasiveness of conventional open repair of the ascending aorta and/or aortic arch. Unfortunately, accessibility to the ascending aorta, in order to perform EVAR, can be challenging as the transfemoral approach might be cumbersome, or because the ascending aorta might not be appropriate for stentgraft landing. This paper will present some technical tips and tricks to achieve successful stentgraft landing in zone 0.
Post-operative computed tomography imaging evaluation of ascending aorta surgery
2021
Ascending thoracic aorta disease is often a life-threatening condition. Aortic aneurysm and aortic dissection are the most frequent ascending aorta diseases requiring surgical intervention. Surgical repair techniques of the ascending aorta are various; they include reconstruction of the ascending aorta by using a graft with or without a prosthetic valve, reconstruction with a composite artificial graft or using a biological graft, and reconstruction of the ascending aorta with a composite graft preserving the native valve and arch repair. The radiologist plays a key role in the identification of post-operative complications; differentiation from normal postoperative findings is fundamental.…
Estudio de miRNAs en la formación de aneurismas de aorta abdominal en humanos
2021
Los microRNA (miRNAs/miRs) son pequeñas cadenas de ácido ribonucleico (ARN, del inglés RNA) que regulan diferentes procesos biológicos. El objetivo de este estudio consistió en identificar miRNAs alterados en plasma y tejido de pacientes con aneurismas de aorta abdominal (AAA) y explorar nuevas dianas potencialmente involucradas en su desarrollo. Cincuenta y siete sujetos fueron reclutados para el estudio en plasma (30 pacientes con AAA, 16 voluntarios sanos y 11 paciente con arterioesclerosis). Se testó el nivel de expresión de 179 miRNAs en un subgrupo de las muestras de plasma y, posteriormente, se validaron los miRNAs disregulados en la población completa. Los miRNA alterados también se…
Zator tętnicy środkowej siatkówki jako pierwsza manifestacja kliniczna w postaci powikłania zatorowo-zakrzepowego jednopłatkowej zastawki aortalnej—o…
2018
Jednopłatkowa zastawka aortalna (UAV) jest rzadką wrodzoną wadą zastawki aortalnej. Przegląd literatury sugeruje, że szacowana częstość jej występowania wynosi 0,02%. W artykule przedstawiono przypadek 40-letniego pacjenta z UAV z ciężką stenozą. Etiologia jednopłatkowej zastawki aortalnej jest najczęściej wrodzona, jednak w opisanym przypadku rozpatruje się ją na dwóch możliwych podłożach — jako wadę wrodzoną o podtypie slit-shaped unicomissural lub jako wadę nabytą o degeneracyjnej postaci zwężenia zastawki. Pierwszą manifestacją choroby u pacjenta było powikłanie zakrzepowo-zatorowe w postaci zatoru tętnicy środkowej siatkówki objawiające się nagłym zaniewidzeniem. Chorego skierowano na …
A Non-Local Mode-I Cohesive Model for Ascending Thoracic Aorta Dissections (ATAD)
2018
This paper presents a non-local interface mechanical model to describe aortic dissection. In this regard, the mode-I debonding problem based on a cohesive zone modeling is endowed with non-local terms to include long-range interactions that are present in multi-layered biological tissue. Such non-local effects are related to the collagen fibers that transmit forces between non-adjacent elements. Numerical simulations are provided with different values of the non-local parameters in order to show the effect of the non-locality during the debonding processes.
Extracellular matrix fiber microarchitecture is region-specific in bicuspid aortic valve-associated ascending aortopathy
2016
Abstract Objective Ascending thoracic aortic aneurysm (ATAA) in patients with bicuspid aortic valve (BAV) commonly dilate asymmetrically compared with patients with tricuspid aortic valve (TAV). This discrepancy in aneurysm geometry led us to hypothesize that microarchitectural differences underlie the observed asymmetric dilatation pattern. The purpose of this study was to characterize the microarchitectural distinctions of the extracellular matrix of the 2 phenotypes with a focus on the proportion of radially oriented elastin and collagen fibers in different circumferential aortic regions. Methods Aortic tissue rings were obtained just distal to the sinotubular junction from patients with…
Endovascular treatment of spontaneous isolated abdominal aortic dissection
2016
Isolated abdominal aortic dissection is a rare clinical disease representing only 1.3% of all dissections. There are a few case series reported in the literature. The causes of this pathology can be spontaneous, iatrogenic, or traumatic. Most patients are asymptomatic and symptoms are usually abdominal or back pain, while claudication and lower limb ischemia are rare. Surgical and endovascular treatment are two valid options with acceptable results. We herein describe nine cases of symptomatic spontaneous isolated abdominal aortic dissection, out of which four successfully were treated with an endovascular approach between July 2003 and July 2013. All patients were men, smokers, symptomati…
Functional Morphology of Human Arteries During Fetal and Postnatal Development
1980
The equilibrium between the distending force of the blood pressure and the arterial wall is determined essentially by a simple law of mechanics, the law of Laplace. According to this law, the total force or tension (T) in the vessel’s wall represents the product of the radius of the vessel (r) and the blood pressure (p), T = r.p. The law of Laplace may be used to estimate and compare the tension produced by blood pressure in vessels of different size and thereby determine the increase in functional load on arteries. Since tension increases not only with blood pressure but also with the radius of the vessel, the highest tension is presumably produced in the wall of the ascending aorta where …