Search results for "aorta"

Myocardial Protection by Retrograde Cardioplegic Perfusion in the Presence of Acute Coronary Artery Obstruction: An Experimental Study

1992

To investigate retrograde delivery of cardioplegic solutions as a means of enhancing myocardial protection in the presence of coronary artery occlusion, a two-part experimental model was devised. In part 1 (in vitro) the possibility of retroperfusing the entire myocardium during acute occlusion of the left anterior descending artery (LAD) was assessed. In part 2 (in vivo) acute LAD occlusion was performed in dogs, and during 2 hours of aortic cross-clamping crystalline cardioplegic solution was infused at 20-minute intervals. In group I the infusion was antegrade, via the aortic root, and in group II it was retrograde, via the coronary sinus. Thereafter the LAD snare was released and the do…

Complement C6 deficiency protects against diet-induced atherosclerosis in rabbits.

1998

Abstract —Low-density lipoprotein (LDL) can be transformed to an atherogenic moiety by nonoxidative, enzymatic degradation. Enzymatically degraded LDL induces macrophage foam cell formation, provokes release of cytokines, and also activates complement. To determine whether complement activation may contribute to atherogenesis, 6 pairs of homozygous C6-deficient rabbits and their non–C6-deficient heterozygous siblings were fed a cholesterol-rich diet for 14 weeks. Cholesterol levels and plasma lipoprotein profiles of the animals in the C6-competent and C6-deficient groups did not significantly differ, and the high density lipoprotein and LDL cholesterol ratios at the end of the experiment w…

Transposition of the great arteries and aortopulmonary window in the same patient: clinical report and follow-up.

2002

Trasnposition of great arteries (TGA) Has been reported in combination with several congenital defects. Only one case of TGA has been described in association with aortopulmonary window (APW).

CRP-induced levels of oxidative stress are higher in brain than aortic endothelial cells

2010

C-reactive protein (CRP) has been demonstrated to induce blood-brain barrier disruption (BBB) involving NAD(P)H-oxidase dependent oxidative stress. It is unclear why CRP affects the BBB and not other vascular beds following stroke. Therefore we examined CRP receptor and NAD(P)H-oxidase expression levels in bovine brain- (BEC) and aortic endothelial cells. Dichlorodihydrofluorescein measurements revealed significantly higher CRP-induced reactive oxygen species (ROS) levels in BEC. Protein expression of the CRP-receptors CD16, CD32 and of the NAD(P)H-oxidase subunit p22phox were also significantly higher in BEC. In conclusion BEC show a higher vulnerability to CRP due to increased levels of C…

Transperitoneal versus extraperitoneal laparoscopic aortic lymph nodal staging for locally advanced cervical cancer: A systematic review and meta-ana…

2021

Abstract Cervical cancer is the fourth most common neoplasm in women. In locally advanced cervical cancers, the international guidelines recommend nodal aortic assessment. Two techniques have been described to perform laparoscopic aortic lymphadenectomy: transperitoneal laparoscopic lymphadenectomy (TLL) and extraperitoneal laparoscopic lymphadenectomy (ELL). This meta-analysis aims to compare the surgical outcomes of TLL and ELL for staging purposes. The systematic review was carried out in agreement with the preferred reporting items for systematic reviews and meta-analyses statement (PRISMA). Two hundred and twenty studies were analyzed, and 19 studies were included in the review (7 for …

2018

Background The aim of our study was to evaluate the feasibility of exercise cardiac magnetic resonance (CMR) in patients with repaired tetralogy of Fallot (RTOF) and to assess right and left ventricular adaptation and aortic wall response to exercise in comparison with volunteers. Methods 11 RTOF and 11 volunteers underwent prospective CMR at rest and during exercise. A supine bicycle ergometer was employed to reach twice the resting heart rate during continuous exercise, blood pressure and heart rate were recorded. Bi-ventricular parameters and aortic stiffness were assessed using accelerated cine sequences and flow-encoding CMR. A t-test was used to compare values between groups. A Mann W…

NADPH Oxidase Accounts for Enhanced Superoxide Production and Impaired Endothelium-Dependent Smooth Muscle Relaxation in BKβ1 −/− Mice

2006

Objective— Nitric oxide (NO)-induced vasorelaxation involves activation of large conductance Ca 2+ -activated K + channels (BK). A regulatory BKβ1 subunit confers Ca 2+ , voltage, and NO/cGMP sensitivity to the BK channel. We investigated whether endothelial function and NO/cGMP signaling is affected by a deletion of the β1-subunit. Methods and Results— Vascular superoxide in BKβ1 −/− was measured using the fluorescent dye hydroethidine and lucigenin-enhanced chemiluminescence. Vascular NO formation was analyzed using electron paramagnetic resonance (EPR), expression of NADPH oxidase subunits, the endothelial NO synthase (eNOS), the soluble guanylyl cyclase (sGC), as well as the activity a…

PPARγ as an indicator of vascular function in an experimental model of metabolic syndrome in rabbits

2021

Abstract Background and aims Underlying mechanisms associated with vascular dysfunction in metabolic syndrome (MetS) remain unclear and can even vary from one vascular bed to another. Methods In this study, MetS was induced by a high-fat, high-sucrose diet, and after 28 weeks, aorta and renal arteries were removed and used for isometric recording of tension in organ baths, protein expression by Western blot, and histological analysis to assess the presence of atherosclerosis. Results MetS induced a mild hypertension, pre-diabetes, central obesity and dyslipidaemia. Our results indicated that MetS did not change the contractile response in either the aorta or renal artery. Conversely, vasodi…

Endovascular Treatment of Spontaneous and Isolated Infrarenal Acute Aortic Syndrome with Unibody Aortic Stent-Grafts

2020

Abstract Introduction Spontaneous acute aortic syndrome (IAAS) is rarely localized in the infrarenal aorta. The endovascular approach is preferred over conventional open surgery with fewer complications. However, dedicated endovascular devices for IAAS treatment are unavailable. The aim was to report a large single-center experience using unibody stent-grafts to address IAAS. Methods From April 2016 to March 2019, a retrospective analysis of patients presenting spontaneous and isolated IAAS was performed. Patients addressed with the unibody stent-graft (AFX endovascular AAA system; Endologix Inc., Irvine, CA) were included in the study. Indications to IAAS treatment were persistent symptoms…

From Clinical Imaging to Patient-Specific Computational Model: Rapid Adaptation of the Living Heart Human Model to a Case of Aortic Stenosis

2021

Aortic stenosis (AS) is the most common acquired heart valve disease in the developed world. Traditional methods of grading AS have relied on the measurement of aortic valve area and transvalvular pressure gradient. Recent research has highlighted the existence of AS variants that do not meet classic criteria for severe AS such as low-flow, low-gradient AS. With the development of sophisticated multi-scale computational models, investigation into the left ventricular (LV) biomechanics of AS offers new insights into the pathophysiology that may guide treatment decisions surrounding AS. Building upon our prior study entailing LV-aortic coupling where AS conditions were applied to the idealize…