Investigation of pulsatile flowfield in healthy thoracic aorta models.

PubMed

Wen, Chih-Yung; Yang, An-Shik; Tseng, Li-Yu; Chai, Jyh-Wen

2010-02-01

Cardiovascular disease is the primary cause of morbidity and mortality in the western world. Complex hemodynamics plays a critical role in the development of aortic dissection and atherosclerosis, as well as many other diseases. Since fundamental fluid mechanics are important for the understanding of the blood flow in the cardiovascular circulatory system of the human body aspects, a joint experimental and numerical study was conducted in this study to determine the distributions of wall shear stress and pressure and oscillatory WSS index, and to examine their correlation with the aortic disorders, especially dissection. Experimentally, the Phase-Contrast Magnetic Resonance Imaging (PC-MRI) method was used to acquire the true geometry of a normal human thoracic aorta, which was readily converted into a transparent thoracic aorta model by the rapid prototyping (RP) technique. The thoracic aorta model was then used in the in vitro experiments and computations. Simulations were performed using the computational fluid dynamic (CFD) code ACE+((R)) to determine flow characteristics of the three-dimensional, pulsatile, incompressible, and Newtonian fluid in the thoracic aorta model. The unsteady boundary conditions at the inlet and the outlet of the aortic flow were specified from the measured flowrate and pressure results during in vitro experiments. For the code validation, the predicted axial velocity reasonably agrees with the PC-MRI experimental data in the oblique sagittal plane of the thoracic aorta model. The thorough analyses of the thoracic aorta flow, WSSs, WSS index (OSI), and wall pressures are presented. The predicted locations of the maxima of WSS and the wall pressure can be then correlated with that of the thoracic aorta dissection, and thereby may lead to a useful biological significance. The numerical results also suggest that the effects of low WSS and high OSI tend to cause wall thickening occurred along the inferior wall of the aortic arch and the anterior wall of the brachiocephalic artery, similar implication reported in a number of previous studies.

P-selectin expressed by a human SELP transgene is atherogenic in apolipoprotein E-deficient mice

PubMed Central

Zhang, Nan; Liu, Zhenghui; Yao, Longbiao; Mehta-D’souza, Padmaja; McEver, Rodger P.

2016-01-01

Objective During inflammation, P-selectin expressed on activated endothelial cells and platelets mediates rolling adhesion of leukocytes. Atherosclerosis-prone mice crossed with P-selectin-deficient (Selp−/−) mice develop smaller lesions. Cytokines such as tumor necrosis factor-α increase Selp transcripts and augment atherosclerosis in mice. However, they decrease SELP transcripts in humans, challenging assumptions that human P-selectin is atherogenic. We used mice expressing a human SELP transgene to examine the atherogenic role of P-selectin. Approach and results We crossed apolipoprotein E-deficient (Apoe−/−) mice with Selp−/− mice and/or transgenic mice expressing the entire human SELP gene (TgSELP+/−). Aortas developed larger, macrophage-rich atheromas in Apoe−/−Selp−/−TgSELP+/− mice than in Apoe−/−Selp−/− mice after 8 or 16 weeks on a Western diet. Confocal microscopy of Apoe−/−Selp−/−TgSELP+/− aortas revealed staining for human P-selectin in endothelial cells overlying atheromas, but not in lesional macrophages. We also observed staining for human P-selectin in aortic endothelial cells of 3–4-week-old Apoe−/−Selp−/−TgSELP+/− weanlings before atheromas developed. Furthermore, human SELP transcripts were ~3-fold higher in aortas of Apoe−/−Selp+/−TgSELP+/− weanlings than in Selp+/−TgSELP+/− weanlings, whereas murine Selp and Sele transcripts were equivalent in weanlings of both genotypes. Human SELP transcripts in aortas of Apoe−/−Selp+/−TgSELP+/− mice remained nearly constant during 16 weeks on a Western diet, whereas murine Selp and Sele transcripts progressively increased. Bone marrow transplantation in Apoe−/−Selp−/− and Apoe−/−Selp−/−TgSELP+/− mice demonstrated that both platelets and endothelial cells must express human P-selectin to promote atherogenesis. Conclusions P-selectin expressed by human SELP is atherogenic in Apoe−/− mice, suggesting that P-selectin contributes to atherogenesis in humans. PMID:27102967

Calcification detection of abdominal aorta in CT images and 3D visualization in VR devices.

PubMed

Garcia-Berna, Jose A; Sanchez-Gomez, Juan M; Hermanns, Judith; Garcia-Mateos, Gines; Fernandez-Aleman, Jose L

2016-08-01

Automatic calcification detection in abdominal aorta consists of a set of computer vision techniques to quantify the amount of calcium that is found around this artery. Knowing that information, it is possible to perform statistical studies that relate vascular diseases with the presence of calcium in these structures. To facilitate the detection in CT images, a contrast is usually injected into the circulatory system of the patients to distinguish the aorta from other body tissues and organs. This contrast increases the absorption of X-rays by human blood, making it easier the measurement of calcifications. Based on this idea, a new system capable of detecting and tracking the aorta artery has been developed with an estimation of the calcium found surrounding the aorta. Besides, the system is complemented with a 3D visualization mode of the image set which is designed for the new generation of immersive VR devices.

Novel Models to Study Effect of High-Altitude Hypoxic Exposure and Placental Insufficency on Fetal Oxygen Metabolism and Congenital Heart Defects

DTIC Science & Technology

2016-10-01

normally present, such as the 4-chambered heart, the great vessels ( aorta , pulmonary arteries) and their anatomic relationships. A notable abnormality in...connections with the ventricles ( aorta to the left ventricle and pulmonary artery to the right ventricle). These are the most common sites of human...the septum. AO, Aorta ; PA, DoD Award # W81XWH-15-1-0238 Annual Report 21 Figure 5. MATcKO Hif-1α causes reduction in uterine Natural

Loss of Endothelial Barrier in Marfan Mice (mgR/mgR) Results in Severe Inflammation after Adenoviral Gene Therapy

PubMed Central

Weymann, Alexander; Arif, Rawa; Weber, Antje; Zaradzki, Marcin; Richter, Karsten; Ensminger, Stephan; Robinson, Peter Nicholas; Wagner, Andreas H.; Karck, Matthias; Kallenbach, Klaus

2016-01-01

Objectives Marfan syndrome is an autosomal dominant inherited disorder of connective tissue. The vascular complications of Marfan syndrome have the biggest impact on life expectancy. The aorta of Marfan patients reveals degradation of elastin layers caused by increased proteolytic activity of matrix metalloproteinases (MMPs). In this study we performed adenoviral gene transfer of human tissue inhibitor of matrix metalloproteinases-1 (hTIMP-1) in aortic grafts of fibrillin-1 deficient Marfan mice (mgR/mgR) in order to reduce elastolysis. Methods We performed heterotopic infrarenal transplantation of the thoracic aorta in female mice (n = 7 per group). Before implantation, mgR/mgR and wild-type aortas (WT, C57BL/6) were transduced ex vivo with an adenoviral vector coding for human TIMP-1 (Ad.hTIMP-1) or β-galactosidase (Ad.β-Gal). As control mgR/mgR and wild-type aortas received no gene therapy. Thirty days after surgery, overexpression of the transgene was assessed by immunohistochemistry (IHC) and collagen in situ zymography. Histologic staining was performed to investigate inflammation, the neointimal index (NI), and elastin breaks. Endothelial barrier function of native not virus-exposed aortas was evaluated by perfusion of fluorescent albumin and examinations of virus-exposed tissue were performed by transmission electron microscopy (TEM). Results IHC and ISZ revealed sufficient expression of the transgene. Severe cellular inflammation and intima hyperplasia were seen only in adenovirus treated mgR/mgR aortas (Ad.β-Gal, Ad.hTIMP-1 NI: 0.23; 0.43), but not in native and Ad.hTIMP-1 treated WT (NI: 0.01; 0.00). Compared to native mgR/mgR and Ad.hTIMP-1 treated WT aorta, the NI is highly significant greater in Ad.hTIMP-1 transduced mgR/mgR aorta (p = 0.001; p = 0.001). As expected, untreated Marfan grafts showed significant more elastolysis compared to WT (p = 0.001). However, elastolysis in Marfan aortas was not reduced by adenoviral overexpression of hTIMP-1 (compared to untreated Marfan aorta: Ad.hTIMP-1 p = 0.902; control Ad.β-Gal. p = 0.165). The virus-untreated and not transplanted mgR/mgR aorta revealed a significant increase of albumin diffusion through the endothelial barrier (p = 0.037). TEM analysis of adenovirus-exposed mgR/mgR aortas displayed disruption of the basement membrane and basolateral space. Conclusions Murine Marfan aortic grafts developed severe inflammation after adenoviral contact. We demonstrated that fibrillin-1 deficiency is associated with relevant dysfunction of the endothelial barrier that enables adenovirus to induce vessel-harming inflammation. Endothelial dysfunction may play a pivotal role in the development of the vascular phenotype of Marfan syndrome. PMID:26840980

Ex-vivo UV autofluorescence imaging and fluorescence spectroscopy of atherosclerotic pathology in human aorta

NASA Astrophysics Data System (ADS)

Lewis, William; Williams, Maura; Franco, Walfre

2017-02-01

The aim of our study was to identify fluorescence excitation-emission pairs correlated with atherosclerotic pathology in ex-vivo human aorta. Wide-field images of atherosclerotic human aorta were captured using UV and visible excitation and emission wavelength pairs of several known fluorophores to investigate correspondence with gross pathologic features. Fluorescence spectroscopy and histology were performed on 21 aortic samples. A matrix of Pearson correlation coefficients were determined for the relationship between relevant histologic features and the intensity of emission for 427 wavelength pairs. A multiple linear regression analysis indicated that elastin (370/460 nm) and tryptophan (290/340 nm) fluorescence predicted 58% of the variance in intima thickness (R-squared = 0.588, F(2,18) = 12.8, p=.0003), and 48% of the variance in media thickness (R-squared = 0.483, F(2,18) = 8.42, p=.002), suggesting that endogenous fluorescence intensity at these wavelengths can be utilized for improved pathologic characterization of atherosclerotic plaques.

Effect of exercise on hemodynamic conditions in the abdominal aorta.

PubMed

Taylor, C A; Hughes, T J; Zarins, C K

1999-06-01

The beneficial effect of exercise in the retardation of the progression of cardiovascular disease is hypothesized to be caused, at least in part, by the elimination of adverse hemodynamic conditions, including flow recirculation and low wall shear stress. In vitro and in vivo investigations have provided qualitative and limited quantitative information on flow patterns in the abdominal aorta and on the effect of exercise on the elimination of adverse hemodynamic conditions. We used computational fluid mechanics methods to examine the effects of simulated exercise on hemodynamic conditions in an idealized model of the human abdominal aorta. A three-dimensional computer model of a healthy human abdominal aorta was created to simulate pulsatile aortic blood flow under conditions of rest and graded exercise. Flow velocity patterns and wall shear stress were computed in the lesion-prone infrarenal aorta, and the effects of exercise were determined. A recirculation zone was observed to form along the posterior wall of the aorta immediately distal to the renal vessels under resting conditions. Low time-averaged wall shear stress was present in this location, along the posterior wall opposite the superior mesenteric artery and along the anterior wall between the superior and inferior mesenteric arteries. Shear stress temporal oscillations, as measured with an oscillatory shear index, were elevated in these regions. Under simulated light exercise conditions, a region of low wall shear stress and high oscillatory shear index remained along the posterior wall immediately distal to the renal arteries. Under simulated moderate exercise conditions, all the regions of low wall shear stress and high oscillatory shear index were eliminated. This numeric investigation provided detailed quantitative data on the effect of exercise on hemodynamic conditions in the abdominal aorta. Our results indicated that moderate levels of lower limb exercise are necessary to eliminate the flow reversal and regions of low wall shear stress in the abdominal aorta that exist under resting conditions. The lack of flow reversal and increased wall shear stress during exercise suggest a mechanism by which exercise may promote arterial health, namely with the elimination of adverse hemodynamic conditions.

Lipid Emulsion Attenuates Acetylcholine-Induced Relaxation in Isolated Rat Aorta

PubMed Central

Ok, Seong-Ho; Lee, Soo Hee; Yu, Jongsun; Park, Jungchul; Shin, Il-Woo; Lee, Youngju; Cho, Hyunhoo; Choi, Mun-Jeoung; Baik, Jiseok; Hong, Jeong-Min; Han, Jeong Yeol; Lee, Heon Keun; Chung, Young-Kyun; Sohn, Ju-Tae

2015-01-01

We investigated the effect of Lipofundin MCT/LCT and Intralipid on acetylcholine-induced nitric oxide- (NO-) mediated relaxation in rat aorta to determine which lipid emulsion (LE) is more potent in terms of inhibition of NO-induced relaxation. Dose-response curves of responses induced by acetylcholine, the calcium ionophore A23187, and sodium nitroprusside were generated using isolated rat aorta with or without LE. The effect of Lipofundin MCT/LCT on acetylcholine-induced endothelial nitric oxide synthase (eNOS) phosphorylation in human umbilical vein endothelial cells (HUVECs) was investigated using western blotting. Lipofundin MCT/LCT (0.1 and 0.2%) attenuated acetylcholine-induced relaxation in endothelium-intact aorta with or without tiron, whereas 0.2% Intralipid only inhibited relaxation. Lipofundin MCT/LCT inhibited relaxation induced by the calcium ionophore A23187 and sodium nitroprusside in endothelium-intact aorta, but Lipofundin MCT/LCT had no effect on sodium nitroprusside-induced relaxation in the endothelium-denuded aorta. Combined pretreatment with l-arginine plus Lipofundin MCT/LCT increased acetylcholine-induced maximal relaxation in endothelium-intact aorta compared with Lipofundin MCT/LCT alone. l-Arginine attenuated Lipofundin MCT/LCT-mediated inhibition of acetylcholine-induced eNOS phosphorylation in HUVECs. Taken together, Lipofundin MCT/LCT attenuated acetylcholine-induced NO-mediated relaxation via an inhibitory effect on the endothelium including eNOS, which is proximal to activation of guanylyl cyclase. PMID:26273653

Lipid Emulsion Attenuates Acetylcholine-Induced Relaxation in Isolated Rat Aorta.

PubMed

Ok, Seong-Ho; Lee, Soo Hee; Yu, Jongsun; Park, Jungchul; Shin, Il-Woo; Lee, Youngju; Cho, Hyunhoo; Choi, Mun-Jeoung; Baik, Jiseok; Hong, Jeong-Min; Han, Jeong Yeol; Lee, Heon Keun; Chung, Young-Kyun; Sohn, Ju-Tae

2015-01-01

We investigated the effect of Lipofundin MCT/LCT and Intralipid on acetylcholine-induced nitric oxide- (NO-) mediated relaxation in rat aorta to determine which lipid emulsion (LE) is more potent in terms of inhibition of NO-induced relaxation. Dose-response curves of responses induced by acetylcholine, the calcium ionophore A23187, and sodium nitroprusside were generated using isolated rat aorta with or without LE. The effect of Lipofundin MCT/LCT on acetylcholine-induced endothelial nitric oxide synthase (eNOS) phosphorylation in human umbilical vein endothelial cells (HUVECs) was investigated using western blotting. Lipofundin MCT/LCT (0.1 and 0.2%) attenuated acetylcholine-induced relaxation in endothelium-intact aorta with or without tiron, whereas 0.2% Intralipid only inhibited relaxation. Lipofundin MCT/LCT inhibited relaxation induced by the calcium ionophore A23187 and sodium nitroprusside in endothelium-intact aorta, but Lipofundin MCT/LCT had no effect on sodium nitroprusside-induced relaxation in the endothelium-denuded aorta. Combined pretreatment with l-arginine plus Lipofundin MCT/LCT increased acetylcholine-induced maximal relaxation in endothelium-intact aorta compared with Lipofundin MCT/LCT alone. L-Arginine attenuated Lipofundin MCT/LCT-mediated inhibition of acetylcholine-induced eNOS phosphorylation in HUVECs. Taken together, Lipofundin MCT/LCT attenuated acetylcholine-induced NO-mediated relaxation via an inhibitory effect on the endothelium including eNOS, which is proximal to activation of guanylyl cyclase.

High Spatial Resolution Multi-Organ Finite Element Modeling of Ventricular-Arterial Coupling

PubMed Central

Shavik, Sheikh Mohammad; Jiang, Zhenxiang; Baek, Seungik; Lee, Lik Chuan

2018-01-01

While it has long been recognized that bi-directional interaction between the heart and the vasculature plays a critical role in the proper functioning of the cardiovascular system, a comprehensive study of this interaction has largely been hampered by a lack of modeling framework capable of simultaneously accommodating high-resolution models of the heart and vasculature. Here, we address this issue and present a computational modeling framework that couples finite element (FE) models of the left ventricle (LV) and aorta to elucidate ventricular—arterial coupling in the systemic circulation. We show in a baseline simulation that the framework predictions of (1) LV pressure—volume loop, (2) aorta pressure—diameter relationship, (3) pressure—waveforms of the aorta, LV, and left atrium (LA) over the cardiac cycle are consistent with the physiological measurements found in healthy human. To develop insights of ventricular-arterial interactions, the framework was then used to simulate how alterations in the geometrical or, material parameter(s) of the aorta affect the LV and vice versa. We show that changing the geometry and microstructure of the aorta model in the framework led to changes in the functional behaviors of both LV and aorta that are consistent with experimental observations. On the other hand, changing contractility and passive stiffness of the LV model in the framework also produced changes in both the LV and aorta functional behaviors that are consistent with physiology principles. PMID:29551977

Spiral blood flow in aorta-renal bifurcation models.

PubMed

Javadzadegan, Ashkan; Simmons, Anne; Barber, Tracie

2016-01-01

The presence of a spiral arterial blood flow pattern in humans has been widely accepted. It is believed that this spiral component of the blood flow alters arterial haemodynamics in both positive and negative ways. The purpose of this study was to determine the effect of spiral flow on haemodynamic changes in aorta-renal bifurcations. In this regard, a computational fluid dynamics analysis of pulsatile blood flow was performed in two idealised models of aorta-renal bifurcations with and without flow diverter. The results show that the spirality effect causes a substantial variation in blood velocity distribution, while causing only slight changes in fluid shear stress patterns. The dominant observed effect of spiral flow is on turbulent kinetic energy and flow recirculation zones. As spiral flow intensity increases, the rate of turbulent kinetic energy production decreases, reducing the region of potential damage to red blood cells and endothelial cells. Furthermore, the recirculation zones which form on the cranial sides of the aorta and renal artery shrink in size in the presence of spirality effect; this may lower the rate of atherosclerosis development and progression in the aorta-renal bifurcation. These results indicate that the spiral nature of blood flow has atheroprotective effects in renal arteries and should be taken into consideration in analyses of the aorta and renal arteries.

A computational fluid–structure interaction model to predict the biomechanical properties of the artificial functionally graded aorta

PubMed Central

Khosravi, Arezoo; Bani, Milad Salimi; Bahreinizade, Hossein; Karimi, Alireza

2016-01-01

In the present study, three layers of the ascending aorta in respect to the time and space at various blood pressures have been simulated. Two well-known commercial finite element (FE) software have used to be able to provide a range of reliable numerical results while independent on the software type. The radial displacement compared with the time as well as the peripheral stress and von Mises stress of the aorta have calculated. The aorta model was validated using the differential quadrature method (DQM) solution and, then, in order to design functionally graded materials (FGMs) with different heterogeneous indexes for the artificial vessel, two different materials have been employed. Fluid–structure interaction (FSI) simulation has been carried out on the FGM and a natural vessel of the human body. The heterogeneous index defines the variation of the length in a function. The blood pressure was considered to be a function of both the time and location. Finally, the response characteristics of functionally graded biomaterials (FGBMs) models with different values of heterogeneous material parameters were determined and compared with the behaviour of a natural vessel. The results showed a very good agreement between the numerical findings of the FGM materials and that of the natural vessel. The findings of the present study may have implications not only to understand the performance of different FGMs in bearing the stress and deformation in comparison with the natural human vessels, but also to provide information for the biomaterials expert to be able to select a suitable material as an implant for the aorta. PMID:27836981

A machine learning approach as a surrogate of finite element analysis-based inverse method to estimate the zero-pressure geometry of human thoracic aorta.

PubMed

Liang, Liang; Liu, Minliang; Martin, Caitlin; Sun, Wei

2018-05-09

Advances in structural finite element analysis (FEA) and medical imaging have made it possible to investigate the in vivo biomechanics of human organs such as blood vessels, for which organ geometries at the zero-pressure level need to be recovered. Although FEA-based inverse methods are available for zero-pressure geometry estimation, these methods typically require iterative computation, which are time-consuming and may be not suitable for time-sensitive clinical applications. In this study, by using machine learning (ML) techniques, we developed an ML model to estimate the zero-pressure geometry of human thoracic aorta given 2 pressurized geometries of the same patient at 2 different blood pressure levels. For the ML model development, a FEA-based method was used to generate a dataset of aorta geometries of 3125 virtual patients. The ML model, which was trained and tested on the dataset, is capable of recovering zero-pressure geometries consistent with those generated by the FEA-based method. Thus, this study demonstrates the feasibility and great potential of using ML techniques as a fast surrogate of FEA-based inverse methods to recover zero-pressure geometries of human organs. Copyright © 2018 John Wiley & Sons, Ltd.

Monoamine oxidases are mediators of endothelial dysfunction in the mouse aorta.

PubMed

Sturza, Adrian; Leisegang, Matthias S; Babelova, Andrea; Schröder, Katrin; Benkhoff, Sebastian; Loot, Annemarieke E; Fleming, Ingrid; Schulz, Rainer; Muntean, Danina M; Brandes, Ralf P

2013-07-01

Monoamine oxidases (MAOs) generate H(2)O(2) as a by-product of their catalytic cycle. Whether MAOs are mediators of endothelial dysfunction is unknown and was determined here in the angiotensin II and lipopolysaccharide-models of vascular dysfunction in mice. Quantitative real-time polymerase chain reaction revealed that mouse aortas contain enzymes involved in catecholamine generation and MAO-A and MAO-B mRNA. MAO-A and -B proteins could be detected by Western blot not only in mouse aortas but also in human umbilical vein endothelial cells. Ex vivo incubation of mouse aorta with recombinant MAO-A increased H(2)O(2) formation and induced endothelial dysfunction that was attenuated by polyethylene glycol-catalase and MAO inhibitors. In vivo lipopolysaccharide (8 mg/kg IP overnight) or angiotensin II (1 mg/kg per day, 2 weeks, minipump) treatment induced vascular MAO-A and -B expressions and resulted in attenuated endothelium-dependent relaxation of the aorta in response to acetylcholine. MAO inhibitors reduced the lipopolysaccharide- and angiotensin II-induced aortic reactive oxygen species formation by 50% (ferrous oxidation xylenol orange assay) and partially normalized endothelium-dependent relaxation. MAO-A and MAO-B inhibitors had an additive effect; combined application completely restored endothelium-dependent relaxation. To determine how MAO-dependent H(2)O(2) formation induces endothelial dysfunction, cyclic GMP was measured. Histamine stimulation of human umbilical vein endothelial cells to activate endothelial NO synthase resulted in an increase in cyclic GMP, which was almost abrogated by MAO-A exposure. MAO inhibition prevented this effect, suggesting that MAO-induced H(2)O(2) formation is sufficient to attenuate endothelial NO release. Thus, MAO-A and MAO-B are both expressed in the mouse aorta, induced by in vivo lipopolysaccharide and angiotensin II treatment and contribute via the generation of H(2)O(2) to endothelial dysfunction in vascular disease models.

Differential Stiffening between the Abdominal and Thoracic Aorta: Effect of Salt Loading in Stroke-Prone Hypertensive Rats.

PubMed

Lindesay, George; Bézie, Yvonnick; Ragonnet, Christophe; Duchatelle, Véronique; Dharmasena, Chandima; Villeneuve, Nicole; Vayssettes-Courchay, Christine

2018-06-08

Central artery stiffening is recognized as a cardiovascular risk. The effects of hypertension and aging have been shown in human and animal models but the effect of salt is still controversial. We studied the effect of a high-salt diet on aortic stiffness in salt-sensitive spontaneously hypersensitive stroke-prone rats (SHRSP). Distensibility, distension, and β-stiffness were measured at thoracic and abdominal aortic sites in the same rats, using echotracking recording of the aortic diameter coupled with blood pressure (BP), in SHRSP-salt (5% salted diet, 5 weeks), SHRSP, and normotensive Wistar-Kyoto (WKY) rats. Hemodynamic parameters were measured at BP matched to that of WKY. Histological staining and immunohistochemistry were used for structural analysis. Hemodynamic isobaric parameters in SHRSP did not differ from WKY and only those from the abdominal aorta of SHRSP-salt presented decreased distensibility and increased stiffness compared with WKY and SHRSP. The abdominal and thoracic aortas presented similar thickening, increased fibrosis, and remodeling with no change in collagen content. SHRSP-salt presented a specific increased elastin disarray at the abdominal aorta level but a decrease in elastin content in the thoracic aorta. This study demonstrates the pro-stiffening effect of salt in addition to hypertension; it shows that only the abdominal aorta presents a specific pressure-independent stiffening, in which elastin disarray is likely a key mechanism. © 2018 S. Karger AG, Basel.

Intracorporeal Heat Distribution from Fully Implantable Energy Sources for Mechanical Circulatory Support: A Computational Proof-of-Concept Study

PubMed Central

Biasetti, Jacopo; Pustavoitau, Aliaksei; Spazzini, Pier Giorgio

2017-01-01

Mechanical circulatory support devices, such as total artificial hearts and left ventricular assist devices, rely on external energy sources for their continuous operation. Clinically approved power supplies rely on percutaneous cables connecting an external energy source to the implanted device with the associated risk of infections. One alternative, investigated in the 70s and 80s, employs a fully implanted nuclear power source. The heat generated by the nuclear decay can be converted into electricity to power circulatory support devices. Due to the low conversion efficiencies, substantial levels of waste heat are generated and must be dissipated to avoid tissue damage, heat stroke, and death. The present work computationally evaluates the ability of the blood flow in the descending aorta to remove the locally generated waste heat for subsequent full-body distribution and dissipation, with the specific aim of investigating methods for containment of local peak temperatures within physiologically acceptable limits. To this aim, coupled fluid–solid heat transfer computational models of the blood flow in the human aorta and different heat exchanger architectures are developed. Particle tracking is used to evaluate temperature histories of cells passing through the heat exchanger region. The use of the blood flow in the descending aorta as a heat sink proves to be a viable approach for the removal of waste heat loads. With the basic heat exchanger design, blood thermal boundary layer temperatures exceed 50°C, possibly damaging blood cells and proteins. Improved designs of the heat exchanger, with the addition of fins and heat guides, allow for drastically lower blood temperatures, possibly leading to a more biocompatible implant. The ability to maintain blood temperatures at biologically compatible levels will ultimately allow for the body-wise distribution, and subsequent dissipation, of heat loads with minimum effects on the human physiology. PMID:29094038

Intracorporeal Heat Distribution from Fully Implantable Energy Sources for Mechanical Circulatory Support: A Computational Proof-of-Concept Study.

PubMed

Biasetti, Jacopo; Pustavoitau, Aliaksei; Spazzini, Pier Giorgio

2017-01-01

Mechanical circulatory support devices, such as total artificial hearts and left ventricular assist devices, rely on external energy sources for their continuous operation. Clinically approved power supplies rely on percutaneous cables connecting an external energy source to the implanted device with the associated risk of infections. One alternative, investigated in the 70s and 80s, employs a fully implanted nuclear power source. The heat generated by the nuclear decay can be converted into electricity to power circulatory support devices. Due to the low conversion efficiencies, substantial levels of waste heat are generated and must be dissipated to avoid tissue damage, heat stroke, and death. The present work computationally evaluates the ability of the blood flow in the descending aorta to remove the locally generated waste heat for subsequent full-body distribution and dissipation, with the specific aim of investigating methods for containment of local peak temperatures within physiologically acceptable limits. To this aim, coupled fluid-solid heat transfer computational models of the blood flow in the human aorta and different heat exchanger architectures are developed. Particle tracking is used to evaluate temperature histories of cells passing through the heat exchanger region. The use of the blood flow in the descending aorta as a heat sink proves to be a viable approach for the removal of waste heat loads. With the basic heat exchanger design, blood thermal boundary layer temperatures exceed 50°C, possibly damaging blood cells and proteins. Improved designs of the heat exchanger, with the addition of fins and heat guides, allow for drastically lower blood temperatures, possibly leading to a more biocompatible implant. The ability to maintain blood temperatures at biologically compatible levels will ultimately allow for the body-wise distribution, and subsequent dissipation, of heat loads with minimum effects on the human physiology.

Dihydroquercetin Does Not Affect Age-Dependent Increase in Blood Pressure and Angiotensin-Converting Enzyme Activity in the Aorta of Hypertensive Rats.

PubMed

Slashcheva, G A; Rykov, V A; Lobanov, A V; Murashev, A N; Kim, Yu A; Arutyunyan, T V; Korystova, A F; Kublik, L N; Levitman, M Kh; Shaposhnikona, V V; Korystov, Yu N

2016-09-01

We analyzed changes in angiotensin-converting enzyme activity in the aorta of hypertensive SHR rats against the background of age-related BP increase (from week 7 to 14) and the effect of dihydroquercetin on BP rise and angiotensin-converting enzyme activity. Normotensive WKY rats of the same age were used as the control. BP and activity of angiotensin-converting enzyme in the aorta of SHR rats increased with age. Dihydroquercetin in doses of 100 and 300 μg/kg per day had no effect on the increase of these parameters; dihydroquercetin administered to 14-week-old WKY rats in a dose of 300 μg/kg reduced activity of the angiotensin-converting enzyme. Thus, the early (7-14 weeks) increase in BP and angiotensin-converting enzyme activity in the aorta of SHR rats was not modified by flavonoids (dihydroquercetin) in contrast to other rat strains and humans, which is indicative of specificity of hypertension mechanism in SHR rats.

Linear and Nonlinear Viscoelastic Modeling of Aorta and Carotid Pressure-Area Dynamics under in vivo and ex vivo Conditions

PubMed Central

Valdez-Jasso, Daniela; Bia, Daniel; Zócalo, Yanina; Armentano, Ricardo L.; Haider, Mansoor A.; Olufsen, Mette S.

2013-01-01

A better understanding of the biomechanical properties of the arterial wall provides important insight into arterial vascular biology under normal (healthy) and pathological conditions. This insight has potential to improve tracking of disease progression and to aid in vascular graft design and implementation. In this study, we use linear and nonlinear viscoelastic models to predict biomechanical properties of the thoracic descending aorta and the carotid artery under ex vivo and in vivo conditions in ovine and human arteries. Models analyzed include a four-parameter (linear) Kelvin viscoelastic model and two five-parameter nonlinear viscoelastic models (an arctangent and a sigmoid model) that relate changes in arterial blood pressure to the vessel cross-sectional area (via estimation of vessel strain). These models were developed using the framework of Quasilinear Viscoelasticity (QLV) theory and were validated using measurements from the thoracic descending aorta and the carotid artery obtained from human and ovine arteries. In vivo measurements were obtained from ten ovine aortas and ten human carotid arteries. Ex vivo measurements (from both locations) were made in eleven male Merino sheep. Biomechanical properties were obtained through constrained estimation of model parameters. To further investigate the parameter estimates we computed standard errors and confidence intervals and we used analysis of variance to compare results within and between groups. Overall, our results indicate that optimal model selection depends on the arterial type. Results showed that for the thoracic descending aorta (under both experimental conditions) the best predictions were obtained with the nonlinear sigmoid model, while under healthy physiological pressure loading the carotid arteries nonlinear stiffening with increasing pressure is negligible, and consequently, the linear (Kelvin) viscoelastic model better describes the pressure-area dynamics in this vessel. Results comparing biomechanical properties show that the Kelvin and sigmoid models were able to predict the zero-pressure vessel radius; that under ex vivo conditions vessels are more rigid, and comparatively, that the carotid artery is stiffer than the thoracic descending aorta; and that the viscoelastic gain and relaxation parameters do not differ significantly between vessels or experimental conditions. In conclusion, our study demonstrates that the proposed models can predict pressure-area dynamics and that model parameters can be extracted for further interpretation of biomechanical properties. PMID:21203846

Modeling the Biodynamical Response of the Human Thorax with Body Armor from a Bullet Impact

DTIC Science & Technology

2001-03-01

inferior vena cava to the right auricle. From the right auricle, the blood is passed into the right ventricle. The right ventricle pumps the blood...the rib and vertebrae is modeled with two beam elements. To create the subcoastal angle, vertical cartilaginous connections at the inferior edge of...brachiocephalic aorta, the aorta, pulmonary arteries and veins, internal jugular veins, brachial veins, and superior vena cava . These vessels are modeled

Peroxisome proliferator-activated receptor (PPAR)-gamma expression in human vascular smooth muscle cells: inhibition of growth, migration, and c-fos expression by the peroxisome proliferator-activated receptor (PPAR)-gamma activator troglitazone.

PubMed

Benson, S; Wu, J; Padmanabhan, S; Kurtz, T W; Pershadsingh, H A

2000-01-01

This study was conducted to determine whether cultured human coronary artery and aorta vascular smooth muscle (VSM) cells express the nuclear transcription factor peroxisome proliferator-activated receptor-gamma (PPARgamma); whether the thiazolidinedione troglitazone, a ligand for PPARgamma, would inhibit c-fos expression by these cells; and whether troglitazone would inhibit proliferation and migration induced in these cells by mitogenic growth factors. Using immunoblotting and reverse-transcriptase polymerase chain reaction (RT-PCR) techniques, we show that both human aorta and coronary artery VSM cell lines expressed PPARgamma protein and mRNA for both PPARgamma isoforms, PPARgamma1 and PPARgamma2. Immunocytochemical staining localized the PPARgamma protein primarily within the nucleus. Troglitazone inhibited basic fibroblast growth factor and platelet-derived growth factor-BB induced DNA synthesis in a dose-dependent manner and downregulated the growth-factor-induced expression of c-fos. Troglitazone also inhibited the migration of coronary artery VSM cells along a platelet-derived growth factor-BB concentration gradient. These findings demonstrate for the first time the expression and nuclear localization of PPARgamma in human coronary artery and aorta VSM cells. The data also suggest that the downregulation of c-fos expression, growth-factor-induced proliferation, and migration by VSM may, in part, be mediated by activation of the PPARgamma receptor.

Toll-like receptor-4 signaling pathway in aorta aging and diseases: "its double nature".

PubMed

Balistreri, Carmela Rita; Ruvolo, Giovanni; Lio, Domenico; Madonna, Rosalinda

2017-09-01

Recent advances in the field of innate immunity have revealed a complex role of innate immune signaling pathways in both tissue homeostasis and disease. Among them, the Toll-like receptor 4 (TLR-4) pathways has been linked to various pathophysiological conditions, such as cardiovascular diseases (CVDs). This has been interrogated by developing multiple laboratory tools that have shown in animal models and clinical conditions, the involvement of the TLR-4 signaling pathway in the pathophysiology of different CVDs, such as atherosclerosis, ischemic heart disease, heart failure, ischemia-reperfusion injury and aorta aneurysm. Among these, aorta aneurysm, a very complex pathological condition with uncertain etiology and fatal complications (i.e. dissection and rupture), has been associated with the occurrence of high risk cardiovascular conditions, including thrombosis and embolism. In this review, we discuss the possible role of TLR-4 signaling pathway in the development of aorta aneurysm, considering the emerging evidence from ongoing investigations. Our message is that emphasizing the role of TLR-4 signaling pathway in aorta aneurysm may serve as a starting point for future studies, leading to a better understanding of the pathophysiological basis and perhaps the effective treatment of this difficult human disease. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nicotinamide Phosphoribosyltransferase in Smooth Muscle Cells Maintains Genome Integrity, Resists Aortic Medial Degeneration, and Is Suppressed in Human Thoracic Aortic Aneurysm Disease.

PubMed

Watson, Alanna; Nong, Zengxuan; Yin, Hao; O'Neil, Caroline; Fox, Stephanie; Balint, Brittany; Guo, Linrui; Leo, Oberdan; Chu, Michael W A; Gros, Robert; Pickering, J Geoffrey

2017-06-09

The thoracic aortic wall can degenerate over time with catastrophic consequences. Vascular smooth muscle cells (SMCs) can resist and repair artery damage, but their capacities decline with age and stress. Recently, cellular production of nicotinamide adenine dinucleotide (NAD + ) via nicotinamide phosphoribosyltransferase (Nampt) has emerged as a mediator of cell vitality. However, a role for Nampt in aortic SMCs in vivo is unknown. To determine whether a Nampt-NAD + control system exists within the aortic media and is required for aortic health. Ascending aortas from patients with dilated aortopathy were immunostained for NAMPT, revealing an inverse relationship between SMC NAMPT content and aortic diameter. To determine whether a Nampt-NAD + control system in SMCs impacts aortic integrity, mice with Nampt -deficient SMCs were generated. SMC- Nampt knockout mice were viable but with mildly dilated aortas that had a 43% reduction in NAD + in the media. Infusion of angiotensin II led to aortic medial hemorrhage and dissection. SMCs were not apoptotic but displayed senescence associated-ß-galactosidase activity and upregulated p16, indicating premature senescence. Furthermore, there was evidence for oxidized DNA lesions, double-strand DNA strand breaks, and pronounced susceptibility to single-strand breakage. This was linked to suppressed poly(ADP-ribose) polymerase-1 activity and was reversible on resupplying NAD + with nicotinamide riboside. Remarkably, we discovered unrepaired DNA strand breaks in SMCs within the human ascending aorta, which were specifically enriched in SMCs with low NAMPT. NAMPT promoter analysis revealed CpG hypermethylation within the dilated human thoracic aorta and in SMCs cultured from these tissues, which inversely correlated with NAMPT expression. The aortic media depends on an intrinsic NAD + fueling system to protect against DNA damage and premature SMC senescence, with relevance to human thoracic aortopathy. © 2017 American Heart Association, Inc.

Expression of platelet-derived growth factor B is upregulated in patients with thoracic aortic dissection.

PubMed

Meng, Weixin; Liu, Shangdian; Li, Dandan; Liu, Zonghong; Yang, Hui; Sun, Bo; Liu, Hongyu

2018-04-20

Thoracic aortic dissection (TAD) is a serious condition requiring urgent treatment to avoid catastrophic consequences. The inflammatory response is involved in the occurrence and development of TAD, possibly potentiated by platelet-derived growth factors (PDGFs). This study aimed to determine whether expression of PDGF-B (a subunit of PDGF-BB) was increased in TAD patients and to explore the factors responsible for its upregulation and subsequent effects on TAD. Full-thickness ascending aorta wall specimens from TAD patients (n = 15) and control patients (n = 10) were examined for expression of PDGF-B and its receptor (PDGFRB) and in terms of morphology, inflammation, and fibrosis. Blood samples from TAD and control patients were collected to detect plasma levels of PDGF-BB and soluble elastins. Expression levels of PDGF-B, PDGFRB, and collagen I were significantly enhanced in ascending aorta wall specimens from TAD patients compared with controls. Furthermore, soluble elastic fragments and PDGF-BB were significantly increased in plasma from TAD patients compared with controls, and numerous irregular elastic fibers and macrophages were seen in the ascending aorta wall in TAD patients. An increase in elastic fragments in the aorta wall might be responsible for inducing the activation and migration of macrophages to injured sites, leading to elevated expression of PDGF-B, which in turn induces deposition of collagen, disrupts extracellular matrix homeostasis, and increases the stiffness of the aorta wall, resulting in compromised aorta compliance. Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Aorta and pulmonary artery segmentation using optimal surface graph cuts in non-contrast CT

NASA Astrophysics Data System (ADS)

Sedghi Gamechi, Zahra; Arias-Lorza, Andres M.; Pedersen, Jesper Holst; de Bruijne, Marleen

2018-03-01

Accurate measurements of the size and shape of the aorta and pulmonary arteries are important as risk factors for cardiovascular diseases, and for Chronicle Obstacle Pulmonary Disease (COPD).1 The aim of this paper is to propose an automated method for segmenting the aorta and pulmonary arteries in low-dose non-ECGgated non-contrast CT scans. Low contrast and the high noise level make the automatic segmentation in such images a challenging task. In the proposed method, first, a minimum cost path tracking algorithm traces the centerline between user-defined seed points. The cost function is based on a multi-directional medialness filter and a lumen intensity similarity metric. The vessel radius is also estimated from the medialness filter. The extracted centerlines are then smoothed and dilated non-uniformly according to the extracted local vessel radius and subsequently used as initialization for a graph-cut segmentation. The algorithm is evaluated on 225 low-dose non-ECG-gated non-contrast CT scans from a lung cancer screening trial. Quantitatively analyzing 25 scans with full manual annotations, we obtain a dice overlap of 0.94+/-0.01 for the aorta and 0.92+/-0.01 for pulmonary arteries. Qualitative validation by visual inspection on 200 scans shows successful segmentation in 93% of all cases for the aorta and 94% for pulmonary arteries.

Time-Resolved Three-Dimensional Contrast-Enhanced Magnetic Resonance Angiography in Patients with Chronic Expanding and Stable Aortic Dissections.

PubMed

Trojan, Michael; Rengier, Fabian; Kotelis, Drosos; Müller-Eschner, Matthias; Partovi, Sasan; Fink, Christian; Karmonik, Christof; Böckler, Dittmar; Kauczor, Hans-Ulrich; von Tengg-Kobligk, Hendrik

2017-01-01

To prospectively evaluate our hypothesis that three-dimensional time-resolved contrast-enhanced magnetic resonance angiography (TR-MRA) is able to detect hemodynamic alterations in patients with chronic expanding aortic dissection compared to stable aortic dissections. 20 patients with chronic or residual aortic dissection in the descending aorta and patent false lumen underwent TR-MRA of the aorta at 1.5 T and repeated follow-up imaging (mean follow-up 5.4 years). 7 patients showed chronic aortic expansion and 13 patients had stable aortic diameters. Regions of interest were placed in the nondissected ascending aorta and the false lumen of the descending aorta at the level of the diaphragm (FL-diaphragm level) resulting in respective time-intensity curves. For the FL-diaphragm level, time-to-peak intensity and full width at half maximum were significantly shorter in the expansion group compared to the stable group ( p = 0.027 and p = 0.003), and upward and downward slopes of time-intensity curves were significantly steeper ( p = 0.015 and p = 0.005). The delay of peak intensity in the FL-diaphragm level compared to the nondissected ascending aorta was significantly shorter in the expansion group compared to the stable group ( p = 0.01). 3D TR-MRA detects significant alterations of hemodynamics within the patent false lumen of chronic expanding aortic dissections compared to stable aortic dissections.

Human Thiel-Embalmed Cadaveric Aortic Model with Perfusion for Endovascular Intervention Training and Medical Device Evaluation.

PubMed

McLeod, Helen; Cox, Ben F; Robertson, James; Duncan, Robyn; Matthew, Shona; Bhat, Raj; Barclay, Avril; Anwar, J; Wilkinson, Tracey; Melzer, Andreas; Houston, J Graeme

2017-09-01

The purpose of this investigation was to evaluate human Thiel-embalmed cadavers with the addition of extracorporeal driven ante-grade pulsatile flow in the aorta as a model for simulation training in interventional techniques and endovascular device testing. Three human cadavers embalmed according to the method of Thiel were selected. Extracorporeal pulsatile ante-grade flow of 2.5 L per min was delivered directly into the aorta of the cadavers via a surgically placed connection. During perfusion, aortic pressure and temperature were recorded and optimized for physiologically similar parameters. Pre- and post-procedure CT imaging was conducted to plan and follow up thoracic and abdominal endovascular aortic repair as it would be in a clinical scenario. Thoracic endovascular aortic repair (TEVAR) and endovascular abdominal repair (EVAR) procedures were conducted in simulation of a clinical case, under fluoroscopic guidance with a multidisciplinary team present. The Thiel cadaveric aortic perfusion model provided pulsatile ante-grade flow, with pressure and temperature, sufficient to conduct a realistic simulation of TEVAR and EVAR procedures. Fluoroscopic imaging provided guidance during the intervention. Pre- and post-procedure CT imaging facilitated planning and follow-up evaluation of the procedure. The human Thiel-embalmed cadavers with the addition of extracorporeal flow within the aorta offer an anatomically appropriate, physiologically similar robust model to simulate aortic endovascular procedures, with potential applications in interventional radiology training and medical device testing as a pre-clinical model.

CXCR6 regulates the recruitment of pro-inflammatory IL-17A-producing T cells into atherosclerotic aortas

PubMed Central

Butcher, Matthew J.; Wu, Chih-I; Waseem, Tayab

2016-01-01

The adaptive immune response is involved in the development and progression of atherosclerosis and IL-17A+ cells play a role in this disease. Although elevated number of CD4+ IL-17A+ (Th17) and IL-17A+TCRγδ+ T cells are found within murine atherosclerotic aortas and human plaques, the mechanisms governing IL-17A+ T-cell migration to atherosclerotic lesions are unclear. The chemokine receptor CXCR6 is expressed on several T-cell subsets and plays a pro-atherogenic role in atherosclerosis. Here, we used CXCR6-deficient (Cxcr6 GFP/GFP) apolipoprotein E-deficient (Apoe −/−) mice to investigate the involvement of CXCR6 in the recruitment IL-17A+ T cells to atherosclerotic aortas. Flow cytometric analyses revealed reductions in Th17 and IL-17A+TCRγδ+ T cells within aged Cxcr6 GFP/GFP Apoe −/− aortas, in comparison with age-matched Cxcr6 GFP/+ Apoe −/− aortas. Although CXCR6-sufficient IL-17A+ T cells efficiently migrated toward CXCL16, the migration of CXCR6-deficient IL-17A+ T cells was abolished in transwell assays. Importantly, the recruitment of Cxcr6 GFP/GFP Apoe −/− IL-17A+ T cells into the aortas of Apoe −/− recipients was markedly reduced in short-term adoptive transfer experiments. Altogether these results demonstrate an important role of CXCR6 in the regulation of pathological Th17 and IL-17A+TCRγδ+ T-cell recruitment into atherosclerotic lesions. PMID:26614640

CXCR6 regulates the recruitment of pro-inflammatory IL-17A-producing T cells into atherosclerotic aortas.

PubMed

Butcher, Matthew J; Wu, Chih-I; Waseem, Tayab; Galkina, Elena V

2016-05-01

The adaptive immune response is involved in the development and progression of atherosclerosis and IL-17A(+) cells play a role in this disease. Although elevated number of CD4(+) IL-17A(+) (Th17) and IL-17A(+)TCRγδ(+) T cells are found within murine atherosclerotic aortas and human plaques, the mechanisms governing IL-17A(+) T-cell migration to atherosclerotic lesions are unclear. The chemokine receptor CXCR6 is expressed on several T-cell subsets and plays a pro-atherogenic role in atherosclerosis. Here, we used CXCR6-deficient (Cxcr6 (GFP/GFP) ) apolipoprotein E-deficient (Apoe (-/-) ) mice to investigate the involvement of CXCR6 in the recruitment IL-17A(+) T cells to atherosclerotic aortas. Flow cytometric analyses revealed reductions in Th17 and IL-17A(+)TCRγδ(+) T cells within aged Cxcr6 (GFP/GFP) Apoe (-/-) aortas, in comparison with age-matched Cxcr6 (GFP/+) Apoe (-/-) aortas. Although CXCR6-sufficient IL-17A(+) T cells efficiently migrated toward CXCL16, the migration of CXCR6-deficient IL-17A(+) T cells was abolished in transwell assays. Importantly, the recruitment of Cxcr6 (GFP/GFP) Apoe (-/-) IL-17A(+) T cells into the aortas of Apoe (-/-) recipients was markedly reduced in short-term adoptive transfer experiments. Altogether these results demonstrate an important role of CXCR6 in the regulation of pathological Th17 and IL-17A(+)TCRγδ(+) T-cell recruitment into atherosclerotic lesions. © The Japanese Society for Immunology. 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Spontaneous aortic dissecting hematoma in two dogs.

PubMed

Boulineau, Theresa Marie; Andrews-Jones, Lydia; Van Alstine, William

2005-09-01

This report describes 2 cases of spontaneous aortic dissecting hematoma in young Border Collie and Border Collie crossbred dogs. Histology was performed in one of the cases involving an unusual splitting of the elastin present within the wall of the aorta, consistent with elastin dysplasia as described in Marfan syndrome in humans. The first case involved a young purebred Border Collie that died suddenly and the second case involved a Border Collie crossbred dog that died after a 1-month history of seizures. Gross lesions included pericardial tamponade with dissection of the ascending aorta in the former case and thoracic cavity hemorrhage, mediastinal hematoma, and aortic dissection in the latter. Histologic lesions in the case of the Border Collie crossbred dog included a dissecting hematoma of the ascending aorta with elastin dysplasia and right axillary arterial intimal proliferation.

Robust extraction of the aorta and pulmonary artery from 3D MDCT image data

NASA Astrophysics Data System (ADS)

Taeprasartsit, Pinyo; Higgins, William E.

2010-03-01

Accurate definition of the aorta and pulmonary artery from three-dimensional (3D) multi-detector CT (MDCT) images is important for pulmonary applications. This work presents robust methods for defining the aorta and pulmonary artery in the central chest. The methods work on both contrast enhanced and no-contrast 3D MDCT image data. The automatic methods use a common approach employing model fitting and selection and adaptive refinement. During the occasional event that more precise vascular extraction is desired or the method fails, we also have an alternate semi-automatic fail-safe method. The semi-automatic method extracts the vasculature by extending the medial axes into a user-guided direction. A ground-truth study over a series of 40 human 3D MDCT images demonstrates the efficacy, accuracy, robustness, and efficiency of the methods.

Expression of human olfactory receptor 10J5 in heart aorta, coronary artery, and endothelial cells and its functional role in angiogenesis.

PubMed

Kim, Sung-Hee; Yoon, Yeo Cho; Lee, Ae Sin; Kang, NaNa; Koo, JaeHyung; Rhyu, Mee-Ra; Park, Jae-Ho

2015-05-01

ORs are ectopically expressed in non-chemosensory tissues including muscle, kidney, and keratinocytes; however, their physiological roles are largely unknown. We found that human olfactory receptor 10J5 (OR10J5) is expressed in the human aorta, coronary artery, and umbilical vein endothelial cells (HUVEC). Lyral induces Ca(2+) and phosphorylation of AKT in HUVEC. A knockdown study showed the inhibition of the lyral-induced Ca(2+) and the phosphorylation AKT and implied that these processes are mediated by OR10J5. In addition, lyral enhanced migration of HUVEC, which were also inhibited by RNAi in a migration assay. In addition, matrigel plug assay showed that lyral enhanced angiogenesis in vivo. Together these data demonstrate the physiological role of OR10J5 in angiogenesis and represent roles of ORs in HUVEC cells. Copyright © 2015 Elsevier Inc. All rights reserved.

Endothelial function and vascular oxidative stress in long-lived GH/IGF-deficient Ames dwarf mice

PubMed Central

Csiszar, Anna; Labinskyy, Nazar; Perez, Viviana; Recchia, Fabio A.; Podlutsky, Andrej; Mukhopadhyay, Partha; Losonczy, Gyorgy; Pacher, Pal; Austad, Steven N.; Bartke, Andrzej; Ungvari, Zoltan

2008-01-01

Hypopituitary Ames dwarf mice have low circulating growth hormone (GH)/IGF-I levels, and they have extended longevity and exhibit many symptoms of delayed aging. To elucidate the vascular consequences of Ames dwarfism we compared endothelial O2•− and H2O2 production, mitochondrial reactive oxygen species (ROS) generation, expression of antioxidant enzymes, and nitric oxide (NO) production in aortas of Ames dwarf and wild-type control mice. In Ames dwarf aortas endothelial O2•− and H2O2 production and ROS generation by mitochondria were enhanced compared with those in vessels of wild-type mice. In Ames dwarf aortas there was a less abundant expression of Mn-SOD, Cu,Zn-SOD, glutathione peroxidase (GPx)-1, and endothelial nitric oxide synthase (eNOS). NO production and acetylcholine-induced relaxation were also decreased in aortas of Ames dwarf mice. In cultured wild-type mouse aortas and in human coronary arterial endothelial cells treatment with GH and IGF significantly reduced cellular O2•− and H2O2 production and ROS generation by mitochondria and upregulated expression of Mn-SOD, Cu,Zn-SOD, GPx-1, and eNOS. Thus GH and IGF-I promote antioxidant phenotypic changes in the endothelial cells, whereas Ames dwarfism leads to vascular oxidative stress. PMID:18757483

Echocardiographic measurements of the aorta in normal children and young adults.

PubMed

Kaldararova, M; Balazova, E; Tittel, P; Stankovicova, I; Brucknerova, I; Masura, J

2007-01-01

To be able to determine aortic valve and ascending aorta pathology, especially aortic root dilatation, it is important to establish normal aortic dimensions. The aim of the study was to measure the dimensions of the aorta in normal healthy children and young adults in Slovakia. 702 healthy subjects, from newborns to 20 years of age, were examined at our institution. The study was carried out prospectively, by a single observer, using digitized two-dimensional (2D), Doppler and M-mode echocardiography. The aorta was measured at 3 sites: 1. aortic valve annulus, 2. sinuses of Valsalva, 3. sinotubular junction. Patients were divided into 28 groups according to their body surface area (BSA)--from 0.15 to 2.0 m2. All data were statistically evaluated (mean value, 5th and 95th percentile for all BSA groups) and regression equations were calculated for each parameter. All 3 measured aortic parameters correlated closely. Measures of correlation (R-squared) for aortic parameters with the square root of BSA were high: 0.89 for aortic valve annulus, 0.86 for sinuses of Valsalva and 0.86 for sinotubular junction (Tab. 3, Fig. 7, Ref 13). Full Text (Free, PDF) www.bmj.sk

Aortic calcified particles modulate valvular endothelial and interstitial cells.

PubMed

van Engeland, Nicole C A; Bertazzo, Sergio; Sarathchandra, Padmini; McCormack, Ann; Bouten, Carlijn V C; Yacoub, Magdi H; Chester, Adrian H; Latif, Najma

Normal and calcified human valve cusps, coronary arteries, and aortae harbor spherical calcium phosphate microparticles of identical composition and crystallinity, and their role remains unknown. The objective was to examine the direct effects of isolated calcified particles on human valvular cells. Calcified particles were isolated from healthy and diseased aortae, characterized, quantitated, and applied to valvular endothelial cells (VECs) and interstitial cells (VICs). Cell differentiation, viability, and proliferation were analyzed. Particles were heterogeneous, differing in size and shape, and were crystallized as calcium phosphate. Diseased donors had significantly more calcified particles compared to healthy donors (P<.05), but there were no differences between the composition of the particles from healthy and diseased donors. VECs treated with calcified particles showed a significant decrease in CD31 and VE-cadherin and an increase in von Willebrand factor expression, P<.05. There were significantly increased α-SMA and osteopontin in treated VICs (P<.05), significantly decreased VEC and VIC viability (P<.05), and significantly increased number of terminal deoxynucleotidyl transferase dUTP nick end labeling-positive VECs (P<.05) indicating apoptosis when treated with the calcified particles. Isolated calcified particles from human aortae are not innocent bystanders but induce a phenotypical and pathological change of VECs and VICs characteristic of activated and pathological cells. Therapy tailored to reduce these calcified particles should be investigated. Copyright © 2017 Elsevier Inc. All rights reserved.

What is needed to make low-density lipoprotein transport in human aorta computational models suitable to explore links to atherosclerosis? Impact of initial and inflow boundary conditions.

PubMed

De Nisco, Giuseppe; Zhang, Peng; Calò, Karol; Liu, Xiao; Ponzini, Raffaele; Bignardi, Cristina; Rizzo, Giovanna; Deng, Xiaoyan; Gallo, Diego; Morbiducci, Umberto

2018-02-08

Personalized computational hemodynamics (CH) is a promising tool to clarify/predict the link between low density lipoproteins (LDL) transport in aorta, disturbed shear and atherogenesis. However, CH uses simplifying assumptions that represent sources of uncertainty. In particular, modelling blood-side to wall LDL transfer is challenged by the cumbersomeness of protocols needed to obtain reliable LDL concentration profile estimations. This paucity of data is limiting the establishment of rigorous CH protocols able to balance the trade-offs among the variety of in vivo data to be acquired, and the accuracy required by biological/clinical applications. In this study, we analyze the impact of LDL concentration initialization (initial conditions, ICs) and inflow boundary conditions (BCs) on CH models of LDL blood-to-wall transfer in aorta. Technically, in an image-based model of human aorta, two different inflow BCs are generated imposing subject-specific inflow 3D PC-MRI measured or idealized (flat) velocity profiles. For each simulated BC, four different ICs for LDL concentration are applied, imposing as IC the LDL distribution resulting from steady-state simulations with average conditions, or constant LDL concentration values. Based on CH results, we conclude that: (1) the imposition of realistic 3D velocity profiles as inflow BC reduces the uncertainty affecting the representation of LDL transfer; (2) different LDL concentration ICs lead to markedly different patterns of LDL transfer. Given that it is not possible to verify in vivo the proper LDL concentration initialization to be applied, we suggest to carefully set and unambiguously declare the imposed BCs and LDL concentration IC when modelling LDL transfer in aorta, in order to obtain reproducible and ultimately comparable results among different laboratories. Copyright © 2017 Elsevier Ltd. All rights reserved.

Redox stress in Marfan syndrome: Dissecting the role of the NADPH oxidase NOX4 in aortic aneurysm.

PubMed

Jiménez-Altayó, Francesc; Meirelles, Thayna; Crosas-Molist, Eva; Sorolla, M Alba; Del Blanco, Darya Gorbenko; López-Luque, Judit; Mas-Stachurska, Aleksandra; Siegert, Ana-Maria; Bonorino, Fabio; Barberà, Laura; García, Carolina; Condom, Enric; Sitges, Marta; Rodríguez-Pascual, Fernando; Laurindo, Francisco; Schröder, Katrin; Ros, Joaquim; Fabregat, Isabel; Egea, Gustavo

2018-04-01

Marfan syndrome (MFS) is characterized by the formation of ascending aortic aneurysms resulting from altered assembly of extracellular matrix fibrillin-containing microfibrils and dysfunction of TGF-β signaling. Here we identify the molecular targets of redox stress in aortic aneurysms from MFS patients, and investigate the role of NOX4, whose expression is strongly induced by TGF-β, in aneurysm formation and progression in a murine model of MFS. Working models included aortae and cultured vascular smooth muscle cells (VSMC) from MFS patients, and a NOX4-deficient Marfan mouse model (Fbn1 C1039G/+ -Nox4 -/- ). Increased tyrosine nitration and reactive oxygen species levels were found in the tunica media of human aortic aneurysms and in cultured VSMC. Proteomic analysis identified nitrated and carbonylated proteins, which included smooth muscle α-actin (αSMA) and annexin A2. NOX4 immunostaining increased in the tunica media of human Marfan aorta and was transcriptionally overexpressed in VSMC. Fbn1 C1039G/+ -Nox4 -/- mice aortas showed a reduction of fragmented elastic fibers, which was accompanied by an amelioration in the Marfan-associated enlargement of the aortic root. Increase in the contractile phenotype marker calponin in the tunica media of MFS mice aortas was abrogated in Fbn1 C1039G/+ -Nox4 -/- mice. Endothelial dysfunction evaluated by myography in the Marfan ascending aorta was prevented by the absence of Nox4 or catalase-induced H 2 O 2 decomposition. We conclude that redox stress occurs in MFS, whose targets are actin-based cytoskeleton members and regulators of extracellular matrix homeostasis. Likewise, NOX4 have an impact in the progression of the aortic dilation in MFS and in the structural organization of the aortic tunica media, the VSMC phenotypic modulation, and endothelial function. Copyright © 2018 Elsevier Inc. All rights reserved.

EXPRESSION OF NeuGc ON PIG CORNEAS AND ITS POTENTIAL SIGNIFICANCE IN PIG CORNEAL XENOTRANSPLANTATION

PubMed Central

Lee, Whayoung; Miyagawa, Yuko; Long, Cassandra; Ekser, Burcin; Walters, Eric; Ramsoondar, Jagdeece; Ayares, David; Tector, A. Joseph; Cooper, David K. C.; Hara, Hidetaka

2016-01-01

Purpose Pigs expressing neither galactose-α1,3-galactose (Gal) nor N-glycolylneuraminic acid (NeuGc) take xenotransplantation one step closer to the clinic. Our aims were (i) to document the lack of NeuGc expression on corneas and aortas, and cultured endothelial cells (aortic [AECs]; corneal [CECs]) of GTKO/NeuGcKO pigs, and (ii) to investigate whether the absence of NeuGc reduced human antibody binding to the tissues and cells. Methods Wild-type (WT), GTKO, and GTKO/NeuGcKO pig were used for the study. Human tissues and cultured cells were negative controls. Immunofluorescence staining was performed using anti-Gal and anti-NeuGc antibodies, and to determine human IgM and IgG binding to tissues. Flow cytometric analysis was used to determine Gal and NeuGc expression on cultured CECs and AECs and to measure human IgM/IgG binding to these cells. Results Both Gal and NeuGc were detected on WT pig corneas and aortas. Although GTKO pigs expressed NeuGc, neither human nor GTKO/NeuGcKO pigs expressed Gal or NeuGc. Human IgM/IgG binding to corneas and aortas from GTKO and GTKO/NeuGcKO pigs was reduced compared to binding to WT pigs. Human antibody binding to GTKO/NeuGcKO AECs was significantly less than to GTKO AECs, but there was no significant difference in binding between GTKO and GTKO/NeuGcKO CECs. Conclusions The absence of NeuGc on GTKO aortic tissue and AECs is associated with reduced human antibody binding, and possibly will provide better outcome in clinical xenotransplantation using vascularized organs. For clinical corneal xenotransplantation, the absence of NeuGc expression on GTKO/NeuGcKO pig corneas may not prove an advantage over GTKO corneas. PMID:26418433

Time-Resolved Three-Dimensional Contrast-Enhanced Magnetic Resonance Angiography in Patients with Chronic Expanding and Stable Aortic Dissections

PubMed Central

Trojan, Michael; Kotelis, Drosos; Müller-Eschner, Matthias; Partovi, Sasan; Fink, Christian; Karmonik, Christof; Böckler, Dittmar; Kauczor, Hans-Ulrich; von Tengg-Kobligk, Hendrik

2017-01-01

Objective To prospectively evaluate our hypothesis that three-dimensional time-resolved contrast-enhanced magnetic resonance angiography (TR-MRA) is able to detect hemodynamic alterations in patients with chronic expanding aortic dissection compared to stable aortic dissections. Materials and Methods 20 patients with chronic or residual aortic dissection in the descending aorta and patent false lumen underwent TR-MRA of the aorta at 1.5 T and repeated follow-up imaging (mean follow-up 5.4 years). 7 patients showed chronic aortic expansion and 13 patients had stable aortic diameters. Regions of interest were placed in the nondissected ascending aorta and the false lumen of the descending aorta at the level of the diaphragm (FL-diaphragm level) resulting in respective time-intensity curves. Results For the FL-diaphragm level, time-to-peak intensity and full width at half maximum were significantly shorter in the expansion group compared to the stable group (p = 0.027 and p = 0.003), and upward and downward slopes of time-intensity curves were significantly steeper (p = 0.015 and p = 0.005). The delay of peak intensity in the FL-diaphragm level compared to the nondissected ascending aorta was significantly shorter in the expansion group compared to the stable group (p = 0.01). Conclusions 3D TR-MRA detects significant alterations of hemodynamics within the patent false lumen of chronic expanding aortic dissections compared to stable aortic dissections. PMID:29317855

Activation of PPARδ prevents endothelial dysfunction induced by overexpression of amyloid-β precursor protein

PubMed Central

d'Uscio, Livius V.; Das, Pritam; Santhanam, Anantha V.R.; He, Tongrong; Younkin, Steven G.; Katusic, Zvonimir S.

2012-01-01

Aims Existing evidence suggests that amyloid-β precursor protein (APP) causes endothelial dysfunction and contributes to pathogenesis of atherosclerosis. In the present study, experiments were designed to: (1) determine the mechanisms underlying endothelial dysfunction and (2) define the effects of peroxisome proliferator-activated receptor delta (PPARδ) ligand on endothelial function in transgenic Tg2576 mice overexpressing mutated human APP. Methods and results Confocal microscopy and western blot analyses of wild-type mice aortas provided evidence that APP protein is mainly present in endothelial cells. Overexpression of APP significantly impaired endothelium-dependent relaxations to acetylcholine and phosphorylation of endothelial nitric oxide synthase at Ser1177 in aortas. HPLC analysis revealed that tetrahydrobiopterin (BH4) levels were reduced in Tg2576 mice aortas. This was caused by increased oxidation of BH4 and reduced expression and activity of GTP-cyclohydrolase I. Furthermore, gp91phox protein expression and superoxide anion production were increased in aortas of Tg2576 mice. This augmented superoxide formation was completely prevented by the NADPH oxidase inhibitor VAS2870. Expression of copper-/zinc-superoxide dismutase (Cu/ZnSOD) and extracellular SOD was downregulated. Treatment with PPARδ ligand GW501516 (2 mg/kg/day) for 14 days significantly increased BH4 bioavailability and improved endothelium-dependent relaxations in Tg2576 mice aortas. GW501516 also normalized protein expression of gp91phox and SODs, thereby reducing production of superoxide anion in the aortas. Conclusion Our results suggest that in APP transgenic mice loss of nitric oxide and increased oxidative stress are the major causes of endothelial dysfunction. The vascular protective effects of GW501516 in Tg2576 mice appear to be critically dependent on prevention of superoxide anion production. PMID:22886847

Activation of PPARδ prevents endothelial dysfunction induced by overexpression of amyloid-β precursor protein.

PubMed

d'Uscio, Livius V; Das, Pritam; Santhanam, Anantha V R; He, Tongrong; Younkin, Steven G; Katusic, Zvonimir S

2012-12-01

Existing evidence suggests that amyloid-β precursor protein (APP) causes endothelial dysfunction and contributes to pathogenesis of atherosclerosis. In the present study, experiments were designed to: (1) determine the mechanisms underlying endothelial dysfunction and (2) define the effects of peroxisome proliferator-activated receptor delta (PPARδ) ligand on endothelial function in transgenic Tg2576 mice overexpressing mutated human APP. Confocal microscopy and western blot analyses of wild-type mice aortas provided evidence that APP protein is mainly present in endothelial cells. Overexpression of APP significantly impaired endothelium-dependent relaxations to acetylcholine and phosphorylation of endothelial nitric oxide synthase at Ser(1177) in aortas. HPLC analysis revealed that tetrahydrobiopterin (BH(4)) levels were reduced in Tg2576 mice aortas. This was caused by increased oxidation of BH(4) and reduced expression and activity of GTP-cyclohydrolase I. Furthermore, gp91phox protein expression and superoxide anion production were increased in aortas of Tg2576 mice. This augmented superoxide formation was completely prevented by the NADPH oxidase inhibitor VAS2870. Expression of copper-/zinc-superoxide dismutase (Cu/ZnSOD) and extracellular SOD was downregulated. Treatment with PPARδ ligand GW501516 (2 mg/kg/day) for 14 days significantly increased BH(4) bioavailability and improved endothelium-dependent relaxations in Tg2576 mice aortas. GW501516 also normalized protein expression of gp91(phox) and SODs, thereby reducing production of superoxide anion in the aortas. Our results suggest that in APP transgenic mice loss of nitric oxide and increased oxidative stress are the major causes of endothelial dysfunction. The vascular protective effects of GW501516 in Tg2576 mice appear to be critically dependent on prevention of superoxide anion production.

Hybrid Aorta Constructs via In Situ Crosslinking of Poly(glycerol-sebacate) Elastomer Within a Decellularized Matrix.

PubMed

Guler, Selcan; Hosseinian, Pezhman; Aydin, Halil Murat

2017-01-01

Decellularization of tissues and organs has high potential to obtain unique conformation and composition as native tissue structure but may result in weakened tissue mechanical strength. In this study, poly(glycerol-sebacate) (PGS) elastomers were combined with decellularized aorta fragments to investigate the changes in mechanical properties. PGS prepolymer was synthesized via microwave irradiation and then in situ crosslinked within the decellularized aorta extracellular matrix (ECM). Tensile strength (σ) values were found comparable as 0.44 ± 0.10 MPa and 0.57 ± 0.18 MPa for native and hybrid aorta samples, respectively, while elongation at break (ɛ) values were 261% ± 17%, 7.5% ± 0.57%, and 22.18% ± 2.48% for wet control (native), decellularized dried aortae, and hybrid matrices, showing elastic contribution. Young's modulus data indicate that there was a threefold decrease in stiffness compared to decellularized samples once PGS is introduced into the ECM structure. Scanning electron microscopy (SEM) analysis of hybrid grafts revealed that the construct preserves porosity in medial layer of the vessel. Biocompatibility analyses showed no cytotoxic effects on human abdominal aorta smooth muscle cells. Cell studies showed 98% activity in hybrid graft extracts. As a control, collagen coating of the hybrid grafts was performed in the recellularization stage. SEM analysis of recellularized hybrid grafts revealed that cells were attached to the surface of the hybrid graft and proliferated during the 14 days of culture in both groups. This study shows that introducing an elastomer into the native ECM structure following decellularization process can be a useful approach for the preparation of mechanically enhanced composites for soft tissues.

Endothelial AT₁ and AT₂ pathways in aortic responses to angiotensin II after stress and ethanol consumption in rats.

PubMed

Baptista, Rafaela de Fátima Ferreira; Chies, Agnaldo Bruno; Taipeiro, Elane de Fátima; Cordellini, Sandra

2014-12-01

Stress and ethanol are important cardiovascular risk factors. Their vascular and blood pressure (BP) effects were evaluated alone and in combination. Adult male Wistar rats (8-10 per group) were separated into control, ethanol (ethanol 20% in drinking water for 6 weeks), stress (restraint 1 h/d 5 d/week for 6 weeks), and ethanol/stress (in combination) groups. Systolic BP was evaluated weekly. Concentration-response curves for contractile responses to angiotensin II in the absence and the presence of losartan (AT1-blocker), PD123-319 (AT2-blocker), L-NAME (nitric oxide synthase inhibitor), or indomethacin (cyclooxygenase inhibitor) were obtained in isolated intact and endothelium-denuded aortas. Effective concentration 50% (EC50) and maximum response (MR) were compared among groups using MANOVA/Tukey tests. Stress and stress plus ethanol increased BP. Ethanol and stress, alone and in combination, did not alter angiotensin responses of intact aortas. PD123-319 decreased MR to angiotensin II in intact aortas from the ethanol and ethanol/stress groups relative to control in the presence of PD123-319. Losartan increased MR to angiotensin II in intact aortas from the stress and ethanol/stress groups relative to control in the presence of losartan. None of the protocols altered angiotensin responses of denuded aortas. Neither indomethacin nor L-NAME altered angiotensin responses of intact aortas from the experimental groups. Thus ethanol and ethanol plus stress may alter endothelial signaling via AT1-receptors, without changing systemic BP. Stress and stress plus ethanol may alter endothelial signaling via AT2-receptors, and thereby increase BP. Knowledge of such vascular changes induced by stress and/or ethanol may contribute to understanding adverse cardiovascular effects of stress and ethanol consumption in humans.

Remodeling of Aorta Extracellular Matrix as a Result of Transient High Oxygen Exposure in Newborn Rats: Implication for Arterial Rigidity and Hypertension Risk

PubMed Central

Castro, Michele M.; Cloutier, Anik; Bertagnolli, Mariane; Sartelet, Hervé; Germain, Nathalie; Comte, Blandine; Schulz, Richard; DeBlois, Denis; Nuyt, Anne Monique

2014-01-01

Neonatal high-oxygen exposure leads to elevated blood pressure, microvascular rarefaction, vascular dysfunction and arterial (aorta) rigidity in adult rats. Whether structural changes are present in the matrix of aorta wall is unknown. Considering that elastin synthesis peaks in late fetal life in humans, and early postnatal life in rodents, we postulated that transient neonatal high-oxygen exposure can trigger premature vascular remodelling. Sprague Dawley rat pups were exposed from days 3 to 10 after birth to 80% oxygen (vs. room air control) and were studied at 4 weeks. Blood pressure and vasomotor response of the aorta to angiotensin II and to the acetylcholine analogue carbachol were not different between groups. Vascular superoxide anion production was similar between groups. There was no difference between groups in aortic cross sectional area, smooth muscle cell number or media/lumen ratio. In oxygen-exposed rats, aorta elastin/collagen content ratio was significantly decreased, the expression of elastinolytic cathepsin S was increased whereas collagenolytic cathepsin K was decreased. By immunofluorescence we observed an increase in MMP-2 and TIMP-1 staining in aortas of oxygen-exposed rats whereas TIMP-2 staining was reduced, indicating a shift in the balance towards degradation of the extra-cellular matrix and increased deposition of collagen. There was no significant difference in MMP-2 activity between groups as determined by gelatin zymography. Overall, these findings indicate that transient neonatal high oxygen exposure leads to vascular wall alterations (decreased elastin/collagen ratio and a shift in the balance towards increased deposition of collagen) which are associated with increased rigidity. Importantly, these changes are present prior to the elevation of blood pressure and vascular dysfunction in this model, and may therefore be contributory. PMID:24743169

Effects of osteoprotegerin/TNFRSF11B in two models of abdominal aortic aneurysms.

PubMed

Vorkapic, Emina; Kunath, Anne; Wågsäter, Dick

2018-04-27

Osteoprotegerin (OPG), additionally termed tumor necrosis factor receptor superfamily member 11B, is produced by vascular smooth muscle cells (VSMCs) and endothelial cells in the vasculature, and its release may be modulated by pro‑inflammatory cytokines, including interleukin‑1β and tumor necrosis factor‑α. The present study investigated the effects of treatment with low‑dose human recombinant OPG on abdominal aortic aneurysm (AAA) development in mice. Mice were treated with 1 µg human recombinant OPG four times (or vehicle) for 2 weeks prior to inducing AAA. A total of two different models for inducing AAA were used to investigate the hypothesis as to whether OPG is involved in key events of AAA development, using osmotic mini‑pumps with angiotensin II in apolipoprotein‑E (ApoE‑/‑) mice for 28 days or using periaortic application of CaCl2 on the aorta in C57Bl/6J mice for 14 days. OPG was continuously administered during the experimental period. Histological staining using Masson's trichrome, Verhoeff's van‑Gieson and picro‑sirius red, in addition to reverse transcription‑quantitative polymerase chain reaction analysis of various markers, were used to analyze phenotypic alterations. Treatment with OPG had no inhibitory effect on AAA development in the angiotensin II model in ApoE‑/‑ mice, which developed suprarenal aneurysms, although it increased vessel wall thickness of the aorta and total collagen in C57Bl/6J mice using the CaCl2 model that induced infrarenal dilation of the aorta. Treatment with OPG did not inhibit aneurysm development and key events, including inflammation, extracellular matrix or VSMC remodeling, in aortas from OPG‑treated mice with periaortic treatment with CaCl2. The results indicated that mice treated with low levels of human recombinant OPG may have a more stable aneurysmal phenotype due to compensatory production of collagen and increased vessel wall thickness of the aorta, potentially protecting the aneurysm from rupture. Further studies investigating rupture models of AAA in addition to using higher levels of OPG are require to verify this speculation. Furthermore, treatment with low levels of OPG in patients with AAA may represent a novel therapeutic strategy for the treatment of AAA as well as attenuate the adverse effects associated with the administration of normal and high dosages of OPG.

Elastin aging and lipid oxidation products in human aorta.

PubMed

Zarkovic, Kamelija; Larroque-Cardoso, Pauline; Pucelle, Mélanie; Salvayre, Robert; Waeg, Georg; Nègre-Salvayre, Anne; Zarkovic, Neven

2015-01-01

Vascular aging is associated with structural and functional modifications of the arteries, and by an increase in arterial wall thickening in the intima and the media, mainly resulting from structural modifications of the extracellular matrix (ECM) components. Among the factors known to accumulate with aging, advanced lipid peroxidation end products (ALEs) are a hallmark of oxidative stress-associated diseases such as atherosclerosis. Aldehydes generated from the peroxidation of polyunsaturated fatty acids (PUFA), (4-hydroxynonenal, malondialdehyde, acrolein), form adducts on cellular proteins, leading to a progressive protein dysfunction with consequences in the pathophysiology of vascular aging. The contribution of these aldehydes to ECM modification is not known. This study was carried out to investigate whether aldehyde-adducts are detected in the intima and media in human aorta, whether their level is increased in vascular aging, and whether elastin fibers are a target of aldehyde-adduct formation. Immunohistological and confocal immunofluorescence studies indicate that 4-HNE-histidine-adducts accumulate in an age-related manner in the intima, media and adventitia layers of human aortas, and are mainly expressed in smooth muscle cells. In contrast, even if the structure of elastin fiber is strongly altered in the aged vessels, our results show that elastin is not or very poorly modified by 4-HNE. These data indicate a complex role for lipid peroxidation and in particular for 4-HNE in elastin homeostasis, in the vascular wall remodeling during aging and atherosclerosis development. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Elastin aging and lipid oxidation products in human aorta

PubMed Central

Zarkovic, Kamelija; Larroque-Cardoso, Pauline; Pucelle, Mélanie; Salvayre, Robert; Waeg, Georg; Nègre-Salvayre, Anne; Zarkovic, Neven

2014-01-01

Vascular aging is associated with structural and functional modifications of the arteries, and by an increase in arterial wall thickening in the intima and the media, mainly resulting from structural modifications of the extracellular matrix (ECM) components. Among the factors known to accumulate with aging, advanced lipid peroxidation end products (ALEs) are a hallmark of oxidative stress-associated diseases such as atherosclerosis. Aldehydes generated from the peroxidation of polyunsaturated fatty acids (PUFA), (4-hydroxynonenal, malondialdehyde, acrolein), form adducts on cellular proteins, leading to a progressive protein dysfunction with consequences in the pathophysiology of vascular aging. The contribution of these aldehydes to ECM modification is not known. This study was carried out to investigate whether aldehyde-adducts are detected in the intima and media in human aorta, whether their level is increased in vascular aging, and whether elastin fibers are a target of aldehyde-adduct formation. Immunohistological and confocal immunofluorescence studies indicate that 4-HNE-histidine-adducts accumulate in an age-related manner in the intima, media and adventitia layers of human aortas, and are mainly expressed in smooth muscle cells. In contrast, even if the structure of elastin fiber is strongly altered in the aged vessels, our results show that elastin is not or very poorly modified by 4-HNE. These data indicate a complex role for lipid peroxidation and in particular for 4-HNE in elastin homeostasis, in the vascular wall remodeling during aging and atherosclerosis development. PMID:25553420

Infection of endothelial cells by common human viruses.

PubMed

Friedman, H M

1989-01-01

Common human viruses were evaluated for their ability to replicate in the endothelial cells of human umbilical vein and bovine thoracic aorta in vitro. Infection occurred with most viruses. The susceptibilities of endothelial cells derived from bovine aorta, pulmonary artery, and vena cava were compared. Among the viruses studied, no differences were noted in the ability to grow in endothelial cells from these three large vessels. One virus, herpes simplex virus type 1, was evaluated for its ability to produce persistent infection of endothelial cells. Infection developed and persisted for up to 3 months. After the first week, productive infection was found in less than 1% of cells. Nevertheless, the infection markedly affected the growth and morphology of the endothelial monolayer. Infection with any of several different viruses was noted to alter endothelial cell functions, including adherence of granulocytes, production of colony-stimulating factor, and synthesis of matrix protein. In addition, herpes simplex virus type 1 induced receptors for the Fc portion of IgG and for complement component C3b. These findings indicate that common human viruses can profoundly affect the biology of the endothelium.

Towards high-resolution 4D flow MRI in the human aorta using kt-GRAPPA and B1+ shimming at 7T.

PubMed

Schmitter, Sebastian; Schnell, Susanne; Uğurbil, Kâmil; Markl, Michael; Van de Moortele, Pierre-François

2016-08-01

To evaluate the feasibility of aortic 4D flow magnetic resonance imaging (MRI) at 7T with improved spatial resolution using kt-GRAPPA acceleration while restricting acquisition time and to address radiofrequency (RF) excitation heterogeneities with B1+ shimming. 4D flow MRI data were obtained in the aorta of eight subjects using a 16-channel transmit/receive coil array at 7T. Flow quantification and acquisition time were compared for a kt-GRAPPA accelerated (R = 5) and a standard GRAPPA (R = 2) accelerated protocol. The impact of different dynamic B1+ shimming strategies on flow quantification was investigated. Two kt-GRAPPA accelerated protocols with 1.2 × 1.2 × 1.2 mm(3) and 1.8 × 1.8 × 2.4 mm(3) spatial resolution were compared. Using kt-GRAPPA, we achieved a 4.3-fold reduction in net acquisition time resulting in scan times of about 10 minutes. No significant effect on flow quantification was observed compared to standard GRAPPA with R = 2. Optimizing the B1+ fields for the aorta impacted significantly (P <  0.05) the flow quantification while specific B1+ settings were required for respiration navigators. The high-resolution protocol yielded similar flow quantification, but allowed the depiction of branching vessels. 7T in combination with B1+ shimming allows for high-resolution 4D flow MRI acquisitions in the human aorta, while kt-GRAPPA limits total scan times without affecting flow quantification. J. Magn. Reson. Imaging 2016;44:486-499. © 2016 Wiley Periodicals, Inc.

The peri-esophageal connective tissue layers and related compartments: visualization by histology and magnetic resonance imaging.

PubMed

Weijs, T J; Goense, L; van Rossum, P S N; Meijer, G J; van Lier, A L H M W; Wessels, F J; Braat, M N G; Lips, I M; Ruurda, J P; Cuesta, M A; van Hillegersberg, R; Bleys, R L A W

2017-02-01

An organized layer of connective tissue coursing from aorta to esophagus was recently discovered in the mediastinum. The relations with other peri-esophageal fascias have not been described and it is unclear whether this layer can be visualized by non-invasive imaging. This study aimed to provide a comprehensive description of the peri-esophageal fascias and determine whether the connective tissue layer between aorta and esophagus can be visualized by magnetic resonance imaging (MRI). First, T2-weighted MRI scanning of the thoracic region of a human cadaver was performed, followed by histological examination of transverse sections of the peri-esophageal tissue between the thyroid gland and the diaphragm. Secondly, pretreatment motion-triggered MRI scans were prospectively obtained from 34 patients with esophageal cancer and independently assessed by two radiologists for the presence and location of the connective tissue layer coursing from aorta to esophagus. A layer of connective tissue coursing from the anterior aspect of the descending aorta to the left lateral aspect of the esophagus, with a thin extension coursing to the right pleural reflection, was visualized ex vivo in the cadaver on MR images, macroscopic tissue sections, and after histologic staining, as well as on in vivo MR images. The layer connecting esophagus and aorta was named 'aorto-esophageal ligament' and the layer connecting aorta to the right pleural reflection 'aorto-pleural ligament'. These connective tissue layers divides the posterior mediastinum in an anterior compartment containing the esophagus, (carinal) lymph nodes and vagus nerve, and a posterior compartment, containing the azygos vein, thoracic duct and occasionally lymph nodes. The anterior compartment was named 'peri-esophageal compartment' and the posterior compartment 'para-aortic compartment'. The connective tissue layers superior to the aortic arch and at the diaphragm corresponded with the currently available anatomic descriptions. This study confirms the existence of the previously described connective tissue layer coursing from aorta to esophagus, challenging the long-standing paradigm that no such structure exists. A comprehensive, detailed description of the peri-esophageal fascias is provided and, furthermore, it is shown that the connective tissue layer coursing from aorta to esophagus can be visualized in vivo by MRI. © 2016 Anatomical Society.

Deficient Circumferential Growth Is the Primary Determinant of Aortic Obstruction Attributable to Partial Elastin Deficiency.

PubMed

Jiao, Yang; Li, Guangxin; Korneva, Arina; Caulk, Alexander W; Qin, Lingfeng; Bersi, Matthew R; Li, Qingle; Li, Wei; Mecham, Robert P; Humphrey, Jay D; Tellides, George

2017-05-01

Williams syndrome is characterized by obstructive aortopathy attributable to heterozygous loss of ELN , the gene encoding elastin. Lesions are thought to result primarily from excessive smooth muscle cell (SMC) proliferation and consequent medial expansion, although an initially smaller caliber and increased stiffness of the aorta may contribute to luminal narrowing. The relative contributions of such abnormalities to the obstructive phenotype had not been defined. We quantified determinants of luminal stenosis in thoracic aortas of Eln -/- mice incompletely rescued by human ELN . Moderate obstruction was largely because of deficient circumferential growth, most prominently of ascending segments, despite increased axial growth. Medial thickening was evident in these smaller diameter elastin-deficient aortas, with medial area similar to that of larger diameter control aortas. There was no difference in cross-sectional SMC number between mutant and wild-type genotypes at multiple stages of postnatal development. Decreased elastin content was associated with medial fibrosis and reduced aortic distensibility because of increased structural stiffness but preserved material stiffness. Elastin-deficient SMCs exhibited greater contractile-to-proliferative phenotypic modulation in vitro than in vivo. We confirmed increased medial collagen without evidence of increased medial area or SMC number in a small ascending aorta with thickened media of a Williams syndrome subject. Deficient circumferential growth is the predominant mechanism for moderate obstructive aortic disease resulting from partial elastin deficiency. Our findings suggest that diverse aortic manifestations in Williams syndrome result from graded elastin content, and SMC hyperplasia causing medial expansion requires additional elastin loss superimposed on ELN haploinsufficiency. © 2017 American Heart Association, Inc.

Fourier transform infrared spectroscopy to quantify collagen and elastin in an in vitro model of extracellular matrix degradation in aorta.

PubMed

Cheheltani, Rabee; McGoverin, Cushla M; Rao, Jayashree; Vorp, David A; Kiani, Mohammad F; Pleshko, Nancy

2014-06-21

Extracellular matrix (ECM) is a key component and regulator of many biological tissues including aorta. Several aortic pathologies are associated with significant changes in the composition of the matrix, especially in the content, quality and type of aortic structural proteins, collagen and elastin. The purpose of this study was to develop an infrared spectroscopic methodology that is comparable to biochemical assays to quantify collagen and elastin in aorta. Enzymatically degraded porcine aorta samples were used as a model of ECM degradation in abdominal aortic aneurysm (AAA). After enzymatic treatment, Fourier transform infrared (FTIR) spectra of the aortic tissue were acquired by an infrared fiber optic probe (IFOP) and FTIR imaging spectroscopy (FT-IRIS). Collagen and elastin content were quantified biochemically and partial least squares (PLS) models were developed to predict collagen and elastin content in aorta based on FTIR spectra. PLS models developed from FT-IRIS spectra were able to predict elastin and collagen content of the samples with strong correlations (RMSE of validation = 8.4% and 11.1% of the range respectively), and IFOP spectra were successfully used to predict elastin content (RMSE = 11.3% of the range). The PLS regression coefficients from the FT-IRIS models were used to map collagen and elastin in tissue sections of degraded porcine aortic tissue as well as a human AAA biopsy tissue, creating a similar map of each component compared to histology. These results support further application of FTIR spectroscopic techniques for evaluation of AAA tissues.

Fourier Transform Infrared Spectroscopy to Quantify Collagen and Elastin in an In Vitro Model of Extracellular Matrix Degradation in Aorta

PubMed Central

Cheheltani, Rabee; McGoverin, Cushla M.; Rao, Jayashree; Vorp, David A.; Kiani, Mohammad F.; Pleshko, N.

2014-01-01

Extracellular matrix (ECM) is a key component and regulator of many biological tissues including aorta. Several aortic pathologies are associated with significant changes in the composition of the matrix, especially in the content, quality and type of aortic structural proteins, collagen and elastin. The purpose of this study was to develop an infrared spectroscopic methodology that is comparable to biochemical assays to quantify collagen and elastin in aorta. Enzymatically degraded porcine aorta samples were used as a model of ECM degradation in abdominal aortic aneurysm (AAA). After enzymatic treatment, Fourier transform infrared (FTIR) spectra of the aortic tissue were acquired by an infrared fiber optic probe (IFOP) and FTIR imaging spectroscopy (FT-IRIS). Collagen and elastin content were quantified biochemically and partial least squares (PLS) models were developed to predict collagen and elastin content in aorta based on FTIR spectra. PLS models developed from FT-IRIS spectra were able to predict elastin and collagen content of the samples with strong correlations (RMSE of validation = 8.4% and 11.1% of the range respectively), and IFOP spectra were successfully used to predict elastin content (RMSE = 11.3% of the range). The PLS regression coefficients from the FT-IRIS models were used to map collagen and elastin in tissue sections of degraded porcine aortic tissue as well as a human AAA biopsy tissue, creating a similar map of each component compared to histology. These results support further application of FTIR spectroscopic techniques for evaluation of AAA tissues. PMID:24761431

Nestin upregulation characterizes vascular remodeling secondary to hypertension in the rat.

PubMed

Tardif, Kim; Hertig, Vanessa; Duquette, Natacha; Villeneuve, Louis; El-Hamamsy, Ismail; Tanguay, Jean-François; Calderone, Angelino

2015-05-15

Proliferation and hypertrophy of vascular smooth muscle cells represent hallmark features of vessel remodeling secondary to hypertension. The intermediate filament protein nestin was recently identified in vascular smooth muscle cells and in other cell types directly participated in proliferation. The present study tested the hypothesis that vessel remodeling secondary to hypertension was characterized by nestin upregulation in vascular smooth muscle cells. Two weeks after suprarenal abdominal aorta constriction of adult male Sprague-Dawley rats, elevated mean arterial pressure increased the media area and thickness of the carotid artery and aorta and concomitantly upregulated nestin protein levels. In the normal adult rat carotid artery, nestin immunoreactivity was observed in a subpopulation of vascular smooth muscle cells, and the density significantly increased following suprarenal abdominal aorta constriction. Filamentous nestin was detected in cultured rat carotid artery- and aorta-derived vascular smooth muscle cells and an analogous paradigm observed in human aorta-derived vascular smooth muscle cells. ANG II and EGF treatment of vascular smooth muscle cells stimulated DNA and protein synthesis and increased nestin protein levels. Lentiviral short-hairpin RNA-mediated nestin depletion of carotid artery-derived vascular smooth muscle cells inhibited peptide growth factor-stimulated DNA synthesis, whereas protein synthesis remained intact. These data have demonstrated that vessel remodeling secondary to hypertension was characterized in part by nestin upregulation in vascular smooth muscle cells. The selective role of nestin in peptide growth factor-stimulated DNA synthesis has revealed that the proliferative and hypertrophic responses of vascular smooth muscle cells were mediated by divergent signaling events. Copyright © 2015 the American Physiological Society.

Coarctation of the Aorta (For Teens)

MedlinePlus

... for Educators Search English Español Coarctation of the Aorta KidsHealth / For Teens / Coarctation of the Aorta What's ... español Estrechamiento aórtico What Is Coarctation of the Aorta? The aorta (pronounced: ay-OR-tuh) is the ...

The effects of tapering and artery wall stiffness on treatments for Coarctation of the Aorta.

PubMed

Pathirana, Dilan; Johnston, Barbara; Johnston, Peter

2017-11-01

Coarctation of the Aorta is a congenital narrowing of the aorta. Two commonly used treatments are resection and end-to-end anastomosis, and stent placements. We simulate blood flow through one-dimensional models of aortas. Different artery stiffnesses, due to treatments, are included in our model, and used to compare blood flow properties in the treated aortas. We expand our previously published model to include the natural tapering of aortas. We look at change in aorta wall radius, blood pressure and blood flow velocity, and find that, of the two treatments, the resection and end-to-end anastomosis treatment more closely matches healthy aortas.

[The influence of angiotensin-converting enzyme inhibitors on collagen content of the aorta wall in experimental hypercholesterolemia].

PubMed

Wojakowski, W; Gmiński, J; Stajszczyk, M; Goss, M; Siemianowicz, K; Machalski, M

1999-01-01

In atherosclerosis numerous qualitative and quantitative changes in connective tissue metabolism parameters in serum and aorta occur. In atherosclerosis there is an enhanced activity of local renin-angiotensin systems. It leads to overexpression of ANG II, both in serum and arterial wall. ANG II stimulates SMC to over-synthesize the collagens type I and III. Hyper-cholesterolemia is a form of metabolic injury which can both induce phenotypic change of SMC and activate RA system in arterial wall. ACEI lower the accumulation of collagens type I and III, and enhance elastin content in arterial wall in experimental hypertension. The aim of this study was to assess the influence of captopril, enalapril and quinapril on connective tissue metabolism of the aorta in experimental hyper-cholesterolemia. 64 male New Zealand rabbits were used. Animals were fed with standard fodder, special diet (1% cholesterol content) or special diet + tested ACEI. Two doses of ACE inhibitors were used: 1st--equivalent to doses applied to human subjects (in mg/kg of body weight), 2nd--dose 10 times higher. The animals were divided into 8 equal groups: K--standard fodder, B--special diet, C1, C2--special diet + captopril in doses 2.5 and 25 mg/kg/24 hours, respectively, E1, E2--special diet + enalapril in doses 0.75 and 7.5 mg/kg/24 hours, respectively, Q1 i Q2--special diet + quinapril in doses 0.75 and 7.5 mg/kg per day, respectively. The experiment lasted for 6 months. After 24 weeks the animals were sacrificed and aortae were excised for collagens assay. The statistical analysis was performed using ANOVA, followed by LSD test; p < 0.05 was considered statistically significant. The aorta collagens content of cholesterol-fed rabbits significantly increased. The tested ACEI (captopril, enalapril in both doses and quinapril in lower dose) had a preventive effect against the increase of aorta collagen content.

Confocal microscopy for automatic measurement of the density and distance between elastin fibers of histologic preparations of normotensive and hypertensive patients

NASA Astrophysics Data System (ADS)

Vieira, G.; Ferro, D. P.; Adam, R. L.; de Thomaz, A. A.; Cesar, C. L.; Metze, K.

2010-02-01

Elastic fibers are essential components of the human aorta, and there is an association between elastin fibers remodeling and several diseases. Hypertension is one such example of a disease leading to elastin fibers remodeling. These fibers can be easily seen in eosin-hematoxilin (HE) stained histologic sections when observed by UV-excited fluorescence microscopy or by a much more precise Laser Scanning Confocal Microscope (LSCM). In order to study the effect of the hypertension on the elastin fibers pattern we developed an automatic system (software and hardware) to count the number of elastin fibers and to measure the distance between them in a LSCM and used it compare the statistical distribution of the distance between these fibers in normotensive and hypertensive patients. The full image of the whole sample (2 or 3mm long) was composed by several 220×220μm frames with 512×512 pixels. The software counters fiber and distance between fibers. We compared the elastic fiber texture in routinely HE-stained histologic slides of the aorta ascendens in 24 normotensive and 30 hypertensive adult patients of both sexes and of similar age from our autopsy files. Our results show that the average number of fibers is the same for both cases but the distance between the fibers are larger for hypertensive patients than for normotensive ones.

Quantification of regional differences in aortic stiffness in the aging human

PubMed Central

Roccabianca, S.; Figueroa, C.A.; Tellides, G.; Humphrey, J.D.

2013-01-01

There has been a growing awareness over the past decade that stiffening of the aorta, and its attendant effects on hemodynamics, is both an indicator and initiator of diverse cardiovascular, neurovascular, and renovascular diseases. Although different clinical metrics of arterial stiffness have been proposed and found useful in particular situations, there remains a need to understand better the complex interactions between evolving aortic stiffness and the hemodynamics. Computational fluid–solid-interaction (FSI) models are amongst the most promising means to understand such interactions for one can parametrically examine effects of regional variations in material properties and arterial geometry on local and systemic blood pressure and flow. Such models will not only increase our understanding, they will also serve as important steps towards the development of fluid–solid-growth (FSG) models that can further examine interactions between the evolving wall mechanics and hemodynamics that lead to arterial adaptations or disease progression over long periods. In this paper, we present a consistent quantification and comparison of regional nonlinear biaxial mechanical properties of the human aorta based on 19 data sets available in the literature and we calculate associated values of linearized stiffness over the cardiac cycle that are useful for initial large-scale FSI and FSG simulations. It is shown, however, that there is considerable variability amongst the available data and consequently that there is a pressing need for more standardized biaxial testing of the human aorta to collect data as a function of both location and age, particularly for young healthy individuals who serve as essential controls. PMID:23499251

Development of a new bioactivatable fluorescent probe for quantification of apolipoprotein A-I proteolytic degradation in vitro and in vivo.

PubMed

Maafi, Foued; Li, Baoqiang; Gebhard, Catherine; Brodeur, Mathieu R; Nachar, Walid; Villeneuve, Louis; Lesage, Frédéric; Rhainds, David; Rhéaume, Eric; Tardif, Jean-Claude

2017-03-01

The potential benefits of high-density lipoproteins (HDL) against atherosclerosis are attributed to its major protein component, apolipoprotein A-I (apoA-I). Most of the apoA-I in the vascular wall appears to be in its lipid-poor form. The latter, however, is subjected to degradation by proteases localized in atherosclerotic plaques, which, in turn, has been shown to negatively impact its atheroprotective functions. Here, we report the development and in vivo use of a bioactivatable near-infrared full-length apoA-I-Cy5.5 fluorescent probe for the assessment of apoA-I-degrading proteolytic activities. Fluorescence quenching was obtained by saturation of Cy5.5 fluorophore molecules on apoA-I protein. ApoA-I cleavage led to near-infrared fluorescence enhancement. In vitro proteolysis of the apoA-I probe by a variety of proteases including serine, cysteine, and metalloproteases resulted in an up to 11-fold increase in fluorescence (n = 5, p ≤ 0.05). We detected activation of the probe in atherosclerotic mice aorta sections using in situ zymography and showed that broad-spectrum protease inhibitors protected the probe from degradation, resulting in decreased fluorescence (-54%, n = 6 per group, p ≤ 0.0001). In vivo, the injected probe showed stronger fluorescence emission in the aorta of human apoB transgenic Ldlr - /- atherosclerotic mice (ATX) as compared to wild-type mice. In vivo observations were confirmed by ex vivo aorta imaging quantification where a 10-fold increase in fluorescent signal in ATX mice (p ≤ 0.05 vs. control mice) was observed. The use of this probe in different applications may help to assess new molecular mechanisms of atherosclerosis and may improve current HDL-based therapies by enhancing apoA-I functionality. Copyright © 2017 Elsevier B.V. All rights reserved.

Site-specific association between distal aortic pulse wave velocity and peripheral arterial stenosis severity: a prospective cardiovascular magnetic resonance study.

PubMed

van den Bosch, Harrie C M; Westenberg, Jos J M; Setz-Pels, Wikke; Wondergem, John; Wolterbeek, Ron; Duijm, Lucien E M; Teijink, Joep A W; de Roos, Albert

2015-01-20

Vascular disease expression in one location may not be representative for disease severity in other vascular territories, however, strong correlation between disease expression and severity within the same vascular segment may be expected. Therefore, we hypothesized that aortic stiffening is more strongly associated with disease expression in a vascular territory directly linked to that aortic segment rather than in a more remote segment. We prospectively compared the association between aortic wall stiffness, expressed by pulse wave velocity (PWV), sampled in the distal aorta, with the severity of peripheral arterial occlusive disease (PAOD) as compared to atherosclerotic markers sampled in remote vascular territories such as PWV in the proximal aorta and the normalized wall index (NWI), representing the vessel wall thickness, of the left common carotid artery. Forty-two patients (23 men; mean age 64±10 years) underwent velocity-encoded cardiovascular magnetic resonance (CMR) in the proximal and distal aorta, whole-body contrast-enhanced MR angiography (CE-MRA) and carotid vessel wall imaging with black-blood CMR in the work-up for PAOD. Strength of associations between aortic stiffness, carotid NWI and peripheral vascular stenosis grade were assessed and evaluated with multiple linear regression. Stenosis severity correlated well with PWV in the distal aorta (Pearson rP=0.64, p<0.001, Spearman rS=0.65, p<0.001) but to a lesser extent with PWV in the proximal aorta (rP=0.48, p=0.002, rS=0.22, p=0.18). Carotid NWI was not associated with peripheral stenosis severity (rP=0.17, p=0.28, rS=0.14, p=0.37) nor with PWV in the proximal aorta (rP=0.22, p=0.17) nor in the distal aorta (rP=0.21, p=0.18). Correlation between stenosis severity and distal aortic PWV remained statistically significant after correction for age and gender. Distal aortic wall stiffness is more directly related to peripheral arterial stenosis severity than markers from more remote vascular territories such as proximal aortic wall stiffness or carotid arterial wall thickness. Site-specific evaluation of vascular disease may be required for full vascular risk estimation.

The risks of aorta impingement from pedicle screw may increase due to aorta movement during posterior instrumentation in Lenke 5C curve: a computed tomography study.

PubMed

Chen, Ling; Xu, Leilei; Qiu, Yong; Qiao, Jun; Wang, Fei; Liu, Zhen; Shi, Benglong; Qian, Bang-ping; Zhu, Zezhang

2015-07-01

To investigate the aorta movement following correction surgery for patients with thoracolumbar/lumbar scoliosis and to determine the subsequent risk of the aorta impingement for pedicle screw (PS) misplacement. Thirty-six AIS patients with a main thoracolumbar or lumbar curve were included in this study. According to the direction of the main curve, the patients were divided into Group R and Group L, with Group R comprising 16 patients with a right-sided curve and Group L comprising 20 patients with a left-sided curve. All patients underwent CT scans of the lower thoracic and lumbar spine before and after surgery. To identify the relative positions of the aorta to vertebral body, several parameters were measured from the CT images of the middle transverse planes of vertebrae from T11 to L4, including aorta-vertebra angle (α), vertebral rotation angle (β), left safety distance (LSD) and right safety distance (RSD). The risk of the aorta impingement from T11 to L4 was calculated. An intragroup comparison regarding the position of the aorta relative to the vertebral body before and after correction surgery was performed accordingly. After surgery, the aorta moved toward the vertebral body among all levels in both groups. Compared with that in Group L, the aorta in Group R was significantly closer to the entry point at all levels, especially at T11. Before surgery, the aorta in Group R was at a high risk of impingement from left PS placement regardless of the diameters of the simulated screws. While in Group L, the risk of aorta impingement was mainly caused by the right placement of 45 mm PS. After surgery, both groups had an increased risk of aorta impingement from PS insertion, especially at T11. The risk of aorta impingement from PS placement was significantly higher in Group R than in Group L. The risk of aorta impingement increased as the aorta shifted leftward after correction surgery, especially in right-sided Lenke 5C curve. Thus, preoperative risk evaluation could be insufficient for clinical practice due to aorta movement following correction surgery. Surgeons should be aware of the potential risk of aorta impingement, especially when placing PS in patients with right-sided curves.

Segmental and age differences in the elastin network, collagen, and smooth muscle phenotype in the tunica media of the porcine aorta.

PubMed

Tonar, Zbyněk; Kubíková, Tereza; Prior, Claudia; Demjén, Erna; Liška, Václav; Králíčková, Milena; Witter, Kirsti

2015-09-01

The porcine aorta is often used in studies on morphology, pathology, transplantation surgery, vascular and endovascular surgery, and biomechanics of the large arteries. Using quantitative histology and stereology, we estimated the area fraction of elastin, collagen, alpha-smooth muscle actin, vimentin, and desmin within the tunica media in 123 tissue samples collected from five segments (thoracic ascending aorta; aortic arch; thoracic descending aorta; suprarenal abdominal aorta; and infrarenal abdominal aorta) of porcine aortae from growing domestic pigs (n=25), ranging in age from 0 to 230 days. The descending thoracic aorta had the greatest elastin fraction, which decreased proximally toward the aortic arch as well as distally toward the abdominal aorta. Abdominal aortic segments had the highest fraction of actin, desmin, and vimentin positivity and all of these vascular smooth muscle markers were lower in the thoracic aortic segments. No quantitative differences were found when comparing the suprarenal abdominal segments with the infrarenal abdominal segments. The area fraction of actin within the media was comparable in all age groups and it was proportional to the postnatal growth. Thicker aortic segments had more elastin and collagen with fewer contractile cells. The collagen fraction decreased from ascending aorta and aortic arch toward the descending aorta. By revealing the variability of the quantitative composition of the porcine aorta, the results are suitable for planning experiments with the porcine aorta as a model, i.e. power test analyses and estimating the number of samples necessary to achieving a desirable level of precision. The complete primary morphometric data, in the form of continuous variables, are made publicly available for biomechanical modeling of site-dependent distensibility and compliance of the porcine aorta. Copyright © 2015 Elsevier GmbH. All rights reserved.

Prenatal Sonographic Predictors of Neonatal Coarctation of the Aorta.

PubMed

Anuwutnavin, Sanitra; Satou, Gary; Chang, Ruey-Kang; DeVore, Greggory R; Abuel, Ashley; Sklansky, Mark

2016-11-01

To identify practical prenatal sonographic markers for the postnatal diagnosis of coarctation of the aorta. We reviewed the fetal echocardiograms and postnatal outcomes of fetal cases of suspected coarctation of the aorta seen at a single institution between 2010 and 2014. True- and false-positive cases were compared. Logistic regression analysis was used to determine echocardiographic predictors of coarctation of the aorta. Optimal cutoffs for these markers and a multivariable threshold scoring system were derived to discriminate fetuses with coarctation of the aorta from those without coarctation of the aorta. Among 35 patients with prenatal suspicion of coarctation of the aorta, the diagnosis was confirmed postnatally in 9 neonates (25.7% true-positive rate). Significant predictors identified from multivariate analysis were as follows: Z score for the ascending aorta diameter of -2 or less (P = < .001), Z score for the mitral valve annulus of -2 or less (P= .033), Zscore for the transverse aortic arch diameter of -2 or less (P= .028), and abnormal aortic valve morphologic features (P= .026). Among all variables studied, the ascending aortic Z score had the highest sensitivity (78%) and specificity (92%) for detection of coarctation of the aorta. A multivariable threshold scoring system identified fetuses with coarctation of the aorta with still greater sensitivity (89%) and only mildly decreased specificity (88%). The finding of a diminutive ascending aorta represents a powerful and practical prenatal predictor of neonatal coarctation of the aorta. A multivariable scoring system, including dimensions of the ascending and transverse aortas, mitral valve annulus, and morphologic features of the aortic valve, provides excellent sensitivity and specificity. The use of these practical sonographic markers may improve prenatal detection of coarctation of the aorta. © 2016 by the American Institute of Ultrasound in Medicine.

The possible contribution of a general glycosphingolipid transporter, GM2 activator protein, to atherosclerosis.

PubMed

Yanai, Hidekatsu; Yoshida, Hiroshi; Tomono, Yoshiharu; Tada, Norio; Chiba, Hitoshi

2006-12-01

We previously found that oxidized low-density lipoprotein (LDL) elevated the expression of mRNA of GalNAcbeta1-4[NeuNAcalpha2-3]Galbeta1-4Glc-Cer (GM2) ganglioside activator protein, in human monocyte-derived macrophages. Recently, GM2 activator protein has become known as a general glycosphingolipid transporter as well as a specific cofactor for the hydrolysis of GM2 ganglioside by lysosomal beta-hexosaminidase A. Accumulation of glycosphingolipids has been observed in the serum or aorta of atherosclerotic model animals and humans. The proliferation of aortic smooth muscle cells, elevation of LDL uptake by macrophages, interfering LDL clearance by the liver, and enhancement of platelet adhesion to collagen have been proposed as the underlying mechanisms of glycosphingolipid-mediated atherogenesis. The GM2 activator protein can bind, solubilize and transport a broad spectrum of lipid molecules, indicating that GM2 activator protein may function as a general intra- and inter-cellular lipid transport protein. Collectively, elevated levels of GM2 activator protein in the aorta may be another feature of human atherosclerosis.

Quantitative angiographic anatomy of the renal arteries and adjacent aorta in the swine for preclinical studies of intravascular catheterization devices.

PubMed

Sakaoka, Atsushi; Koshimizu, Masafumi; Nakamura, Shintaro; Matsumura, Kiyoshi

2018-05-10

Swine are the most common animal model in preclinical studies of cardiovascular devices. Because of the recent trend for development of new devices for percutaneous catheterization, especially for the renal arteries (RAs), we examined the quantitative anatomical dimensions of the RAs and adjacent aorta in swine. Angiographic images were analyzed in 66 female Yorkshire/Landrace crossbred swine. The diameter of both the right and left main RA was 5.4 ± 0.6 mm. The length of the right main RA was significantly longer than that of the left (29.8 ± 7.5 mm vs. 20.6 ± 5.4 mm, respectively; P<0.001). The diameter of both the right and left branch RA with diameters ≥3 mm (the target vessel diameter of recently developed devices) was 3.8 ± 0.5 mm. The right branch RA was significantly longer than that of the left (18.9 ± 7.8 mm vs. 16.4 ± 7.4 mm, respectively; P<0.05). The branching angle of the right RA from the aorta was significantly smaller than that of the left (91 ± 12° vs. 103 ± 15°, respectively; P<0.001). The diameters of the suprarenal and infrarenal aorta were 10.6 ± 1.1 mm and 9.7 ± 0.9 mm, respectively. In conclusion, because of their similar dimensions to human, swine are an appropriate animal model for assessing the safety of, and determining optimal design of, catheter devices for RAs in simulated clinical use. However, there were species differences in the branching angle and adjacent aorta diameter, suggesting that swine models alone are inadequate to assess the delivery performance of catheter devices for RAs.

Quantitative angiographic anatomy of the renal arteries and adjacent aorta in the swine for preclinical studies of intravascular catheterization devices

PubMed Central

Sakaoka, Atsushi; Koshimizu, Masafumi; Nakamura, Shintaro; Matsumura, Kiyoshi

2018-01-01

Swine are the most common animal model in preclinical studies of cardiovascular devices. Because of the recent trend for development of new devices for percutaneous catheterization, especially for the renal arteries (RAs), we examined the quantitative anatomical dimensions of the RAs and adjacent aorta in swine. Angiographic images were analyzed in 66 female Yorkshire/Landrace crossbred swine. The diameter of both the right and left main RA was 5.4 ± 0.6 mm. The length of the right main RA was significantly longer than that of the left (29.8 ± 7.5 mm vs. 20.6 ± 5.4 mm, respectively; P<0.001). The diameter of both the right and left branch RA with diameters ≥3 mm (the target vessel diameter of recently developed devices) was 3.8 ± 0.5 mm. The right branch RA was significantly longer than that of the left (18.9 ± 7.8 mm vs. 16.4 ± 7.4 mm, respectively; P<0.05). The branching angle of the right RA from the aorta was significantly smaller than that of the left (91 ± 12° vs. 103 ± 15°, respectively; P<0.001). The diameters of the suprarenal and infrarenal aorta were 10.6 ± 1.1 mm and 9.7 ± 0.9 mm, respectively. In conclusion, because of their similar dimensions to human, swine are an appropriate animal model for assessing the safety of, and determining optimal design of, catheter devices for RAs in simulated clinical use. However, there were species differences in the branching angle and adjacent aorta diameter, suggesting that swine models alone are inadequate to assess the delivery performance of catheter devices for RAs. PMID:29353822

Beta2-adrenergic activity modulates vascular tone regulation in lecithin:cholesterol acyltransferase knockout mice.

PubMed

Manzini, S; Pinna, C; Busnelli, M; Cinquanta, P; Rigamonti, E; Ganzetti, G S; Dellera, F; Sala, A; Calabresi, L; Franceschini, G; Parolini, C; Chiesa, G

2015-11-01

Lecithin:cholesterol acyltransferase (LCAT) deficiency is associated with hypoalphalipoproteinemia, generally a predisposing factor for premature coronary heart disease. The evidence of accelerated atherosclerosis in LCAT-deficient subjects is however controversial. In this study, the effect of LCAT deficiency on vascular tone and endothelial function was investigated in LCAT knockout mice, which reproduce the human lipoprotein phenotype. Aortas from wild-type (Lcat(wt)) and LCAT knockout (Lcat(KO)) mice exposed to noradrenaline showed reduced contractility in Lcat(KO) mice (P<0.005), whereas acetylcholine exposure showed a lower NO-dependent relaxation in Lcat(KO) mice (P<0.05). Quantitative PCR and Western blotting analyses suggested an adequate eNOS expression in Lcat(KO) mouse aortas. Real-time PCR analysis indicated increased expression of β2-adrenergic receptors vs wild-type mice. Aorta stimulation with noradrenaline in the presence of propranolol, to abolish the β-mediated relaxation, showed the same contractile response in the two mouse lines. Furthermore, propranolol pretreatment of mouse aortas exposed to L-NAME prevented the difference in responses between Lcat(wt) and Lcat(KO) mice. The results indicate that LCAT deficiency leads to increased β2-adrenergic relaxation and to a consequently decreased NO-mediated vasodilation that can be reversed to guarantee a correct vascular tone. The present study suggests that LCAT deficiency is not associated with an impaired vascular reactivity. Copyright © 2015. Published by Elsevier Inc.

Beta2-adrenergic activity modulates vascular tone regulation in lecithin:cholesterol acyltransferase knockout mice

PubMed Central

Manzini, S.; Pinna, C.; Busnelli, M.; Cinquanta, P.; Rigamonti, E.; Ganzetti, G.S.; Dellera, F.; Sala, A.; Calabresi, L.; Franceschini, G.; Parolini, C.; Chiesa, G.

2015-01-01

Lecithin:cholesterol acyltransferase (LCAT) deficiency is associated with hypoalphalipoproteinemia, generally a predisposing factor for premature coronary heart disease. The evidence of accelerated atherosclerosis in LCAT-deficient subjects is however controversial. In this study, the effect of LCAT deficiency on vascular tone and endothelial function was investigated in LCAT knockout mice, which reproduce the human lipoprotein phenotype. Aortas from wild-type (Lcatwt) and LCAT knockout (LcatKO) mice exposed to noradrenaline showed reduced contractility in LcatKO mice (P < 0.005), whereas acetylcholine exposure showed a lower NO-dependent relaxation in LcatKO mice (P < 0.05). Quantitative PCR and Western blotting analyses suggested an adequate eNOS expression in LcatKO mouse aortas. Real-time PCR analysis indicated increased expression of β2-adrenergic receptors vs wild-type mice. Aorta stimulation with noradrenaline in the presence of propranolol, to abolish the β-mediated relaxation, showed the same contractile response in the two mouse lines. Furthermore, propranolol pretreatment of mouse aortas exposed to L-NAME prevented the difference in responses between Lcatwt and LcatKO mice. The results indicate that LCAT deficiency leads to increased β2-adrenergic relaxation and to a consequently decreased NO-mediated vasodilation that can be reversed to guarantee a correct vascular tone. The present study suggests that LCAT deficiency is not associated with an impaired vascular reactivity. PMID:26254103

Connecting the coronaries: How the coronary plexus develops and is functionalized

PubMed Central

Dyer, Laura; Pi, Xinchun; Patterson, Cam

2015-01-01

The establishment of the coronary circulation is one of the final critical steps during heart development. Despite decades of research, our understanding of how the coronary vasculature develops and connects to the aorta remains limited. This review serves two specific purposes: it addresses recent advances in understanding the origin of the coronary endothelium, and it then focuses on the last crucial step of coronary vasculature development, the connection of the coronary plexus to the aorta. The chick and quail animal models have yielded most of the information for how these connections form, starting with a fine network of vessels that penetrate the aorta and coalesce to form two distinct ostia. Studies in mouse and rat confirm that at least some of these steps are conserved in mammals, but gaps still exist in our understanding of mammalian coronary ostia formation. The signaling cues necessary to guide the coronary plexus to the aorta are also incompletely understood. Hypoxia-inducible transcription factor-1 and its downstream targets are among the few identified genes that promote the formation of the coronary stems. Together, this review summarizes our current knowledge of coronary vascular formation and highlights the significant gaps that remain. In addition, it highlights some of the coronary artery anomalies known to affect human health, demonstrating that even seemingly subtle defects arising from incorrect coronary plexus formation can result in significant health crises. PMID:25173872

Increased shedding of microvesicles from intimal smooth muscle cells in athero-prone areas of the human aorta: implications for understanding of the predisease stage.

PubMed

Bobryshev, Yuri V; Killingsworth, Murray C; Orekhov, Alexander N

2013-01-01

This study evaluated whether a change in the content of matrix microvesicles might occur at the preatherosclerotic stage. Applying quantitative electron microscopic and immunohistochemical analyses, two areas of grossly normal segments of the thoracic aorta were compared: atherosclerosis-prone (AP) areas, situated at the dorsal aspect of the aorta along the rows of intercostal branch origins, and atherosclerosis-resistant (AR) areas, situated at the corresponding sites of the ventral aspect of the aorta. The electron microscopic analysis showed that there were 1.4 times more microvesicles in AP areas than AR areas (p = 0.019). It was found that matrix microvesicles originated as a result of blebbing and shedding of surface membranes of smooth muscle cells. A quantitative analysis of the expression of ADP-ribosylation factor 6 (ARF6), which is known to be involved in membrane trafficking and microvesicle formation, showed that ARF6 expression was 1.3 times higher in AP areas than that in AR areas (p = 0.006). There was a positive correlation between the content of matrix microparticles and the expression of ARF6 by intimal smooth muscle cells (r = 0.61; p < 0.0001). The present study supports the concept that alterations of the arterial intima occur at the predisease stage. Copyright © 2012 S. Karger AG, Basel.

Finite element analysis of helical flows in human aortic arch: A novel index

PubMed Central

Lee, Cheng-Hung; Liu, Kuo-Sheng; Jhong, Guan-Heng; Liu, Shih-Jung; Hsu, Ming-Yi; Wang, Chao-Jan; Hung, Kuo-Chun

2014-01-01

This study investigates the helical secondary flows in the aortic arch using finite element analysis. The relationship between helical flow and the configuration of the aorta in patients of whose three-dimensional images constructed from computed tomography scans was examined. A finite element model of the pressurized root, arch, and supra-aortic vessels was developed to simulate the pattern of helical secondary flows. Calculations indicate that most of the helical secondary flow was formed in the ascending aorta. Angle α between the zero reference point and the aortic ostium (correlation coefficient (r) = −0.851, P = 0.001), the dispersion index of the cross section of the ascending (r = 0.683, P = 0.021) and descending aorta (r = 0.732, P = 0.010), all correlated closely with the presence of helical flow (P < 0.05). Stepwise multiple linear regression analysis confirmed angel α to be independently associated with the helical flow pattern in therein (standardized coefficients = −0.721, P = 0.023). The presence of helical fluid motion based on the atherosclerotic risks of patients, including those associated with diabetes, hypertension, hyperlipidemia, or renal insufficiency, was also evaluated. Numerical simulation of the flow patterns in aortas incorporating the atherosclerotic risks may better explain the mechanism of formation of helical flows and provide insight into causative factors that underlie them. PMID:24803960

Computational fluid dynamics (CFD) study on the fetal aortic coarctation

NASA Astrophysics Data System (ADS)

Zhou, Yue; Zhang, Yutao; Wang, Jingying

2018-03-01

Blood flows in normal and coarctate fetal aortas are simulated by the CFD technique using T-rex grids. The three-dimensional (3-D) digital model of the fetal arota is reconstructed by the computer-aided design (CAD) software based on two-dimensional (2-D) ultrasono tomographic images. Simulation results displays the development and enhancement of the secondary flow structure in the coarctate fetal arota. As the diameter narrow ratio rises greater than 45%, the pressure and wall shear stress (WSS) of the aorta arch increase exponentially, which is consistent with the conventional clinical concept. The present study also demonstrates that CFD is a very promising assistant technique to investigate human cardiovascular diseases.

Facts about Coarctation of the Aorta

MedlinePlus

... Media Policy Makers Facts about Coarctation of the Aorta Recommend on Facebook Tweet Share Compartir Click here ... narrower than usual. What is Coarctation of the Aorta? Coarctation of the aorta is a birth defect ...

Biomechanical analysis of wrapping of the moderately dilated ascending aorta.

PubMed

Plonek, Tomasz; Rylski, Bartosz; Dumanski, Andrzej; Siedlaczek, Przemyslaw; Kustrzycki, Wojciech

2015-08-01

External wrapping is a surgical method performed to prevent the dilatation of the aorta and to decrease the risk of its dissection and rupture. However, it is also believed to cause degeneration of the aortic wall. A biomechanical analysis was thus performed to assess the stress of the aortic wall subjected to external wrapping. A stress analysis using the finite elements method was carried out on three models: a non-dilated aorta, a moderately dilated aorta and a wrapped aorta. The models were subjected to a pulsatile flow (120/80 mmHg) and a systolic aortic annulus motion of 11 mm. The finite elements analysis showed that the stress exerted on the outer surface of the ascending aorta in the wrapping model (0.05-0.8 MPa) was similar to that observed in the normal aorta (0.03-0.7 MPa) and was lower than in the model of a moderately dilated aorta (0.06-1.4 MPa). The stress on the inner surface of the ascending aorta ranged from 0.2 MPa to 0.4 MPa in the model of the normal aorta, from 0.3 to 1.3 MPa in the model of the dilated aorta and from 0.05 MPa to 0.4 MPa in the wrapping model. The results of this study suggest that the aortic wall is subjected to similar stress following a wrapping procedure to the one present in the normal aorta.

Expression of lectin-like oxidized LDL receptor-1 in smooth muscle cells after vascular injury

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eto, Hideyuki; Miyata, Masaaki; Kume, Noriaki

Lectin-like oxidized LDL receptor-1 (LOX-1) is an oxidized LDL receptor, and its role in restenosis after angioplasty remains unknown. We used a balloon-injury model of rabbit aorta, and reverse transcription-polymerase chain reaction revealed that LOX-1 mRNA expression was modest in the non-injured aorta, reached a peak level 2 days after injury, and remained elevated until 24 weeks after injury. Immunohistochemistry and in situ hybridization showed that LOX-1 was not detected in the media of non-injured aorta but expressed in both medial and neointimal smooth muscle cells (SMC) at 2 and 24 weeks after injury. Low concentrations of ox-LDL (10 {mu}g/mL)more » stimulated the cultured SMC proliferation, which was inhibited by antisense oligonucleotides of LOX-1 mRNA. Double immunofluorescense staining showed the colocalization of LOX-1 and proliferating cell nuclear antigen in human restenotic lesion. These results suggest that LOX-1 mediates ox-LDL-induced SMC proliferation and plays a role in neointimal formation after vascular injury.« less

Expression of lectin-like oxidized LDL receptor-1 in smooth muscle cells after vascular injury.

PubMed

Eto, Hideyuki; Miyata, Masaaki; Kume, Noriaki; Minami, Manabu; Itabe, Hiroyuki; Orihara, Koji; Hamasaki, Shuichi; Biro, Sadatoshi; Otsuji, Yutaka; Kita, Toru; Tei, Chuwa

2006-03-10

Lectin-like oxidized LDL receptor-1 (LOX-1) is an oxidized LDL receptor, and its role in restenosis after angioplasty remains unknown. We used a balloon-injury model of rabbit aorta, and reverse transcription-polymerase chain reaction revealed that LOX-1 mRNA expression was modest in the non-injured aorta, reached a peak level 2 days after injury, and remained elevated until 24 weeks after injury. Immunohistochemistry and in situ hybridization showed that LOX-1 was not detected in the media of non-injured aorta but expressed in both medial and neointimal smooth muscle cells (SMC) at 2 and 24 weeks after injury. Low concentrations of ox-LDL (10 microg/mL) stimulated the cultured SMC proliferation, which was inhibited by antisense oligonucleotides of LOX-1 mRNA. Double immunofluorescence staining showed the colocalization of LOX-1 and proliferating cell nuclear antigen in human restenotic lesion. These results suggest that LOX-1 mediates ox-LDL-induced SMC proliferation and plays a role in neointimal formation after vascular injury.

Mechanical Characterization and Material Modeling of Diabetic Aortas in a Rabbit Model.

PubMed

Tong, Jianhua; Yang, F; Li, X; Xu, X; Wang, G X

2018-03-01

Diabetes has been recognized as a major risk factor to cause macrovascular diseases and plays a key role in aortic wall remodeling. However, the effects of diabetes on elastic properties of aortas remain largely unknown and quantitative mechanical data are lacking. Thirty adult rabbits (1.6-2.2 kg) were collected and the type 1 diabetic rabbit model was induced by injection of alloxan. A total of 15 control and 15 diabetic rabbit (abdominal) aortas were harvested. Uniaxial and biaxial tensile tests were performed to measure ultimate tensile strength and to characterize biaxial mechanical behaviors of the aortas. A material model was fitted to the biaxial experimental data to obtain constitutive parameters. Histological and mass fraction analyses were performed to investigate the underlying microstructure and dry weight percentages of elastin and collagen in the control and the diabetic aortas. No statistically significant difference was found in ultimate tensile strength between the control and the diabetic aortas. Regarding biaxial mechanical responses, the diabetic aortas exhibited significantly lower extensibility and significantly higher tissue stiffness than the control aortas. Notably, tissue stiffening occurred in both circumferential and axial directions for the diabetic aortas; however, mechanical anisotropy does not change significantly. The material model was able to fit biaxial experimental data very well. Histology showed that a number of isolated foam cells were embedded in the diabetic aortas and hyperplasia of collagen was identified. The dry weight percentages of collagen within the diabetic aortas increased significantly as compared to the control aortas, whereas no significant change was found for that of elastin. Our data suggest that the diabetes impairs elastic properties and alters microstructure of the aortas and consequently, these changes may further contribute to complex aortic wall remodeling.

Bone Morphogenic Protein 4-Smad-Induced Upregulation of Platelet-Derived Growth Factor AA Impairs Endothelial Function.

PubMed

Hu, Weining; Zhang, Yang; Wang, Li; Lau, Chi Wai; Xu, Jian; Luo, Jiang-Yun; Gou, Lingshan; Yao, Xiaoqiang; Chen, Zhen-Yu; Ma, Ronald Ching Wan; Tian, Xiao Yu; Huang, Yu

2016-03-01

Bone morphogenic protein 4 (BMP4) is an important mediator of endothelial dysfunction in cardio-metabolic diseases, whereas platelet-derived growth factors (PDGFs) are major angiogenic and proinflammatory mediator, although the functional link between these 2 factors is unknown. The present study investigated whether PDGF mediates BMP4-induced endothelial dysfunction in diabetes mellitus. We generated Ad-Bmp4 to overexpress Bmp4 and Ad-Pdgfa-shRNA to knockdown Pdgfa in mice through tail intravenous injection. SMAD4-shRNA lentivirus, SMAD1-shRNA, and SMAD5 shRNA adenovirus were used for knockdown in human and mouse endothelial cells. We found that PDGF-AA impaired endothelium-dependent vasodilation in aortas and mesenteric resistance arteries. BMP4 upregulated PDGF-AA in human and mouse endothelial cells, which was abolished by BMP4 antagonist noggin or knockdown of SMAD1/5 or SMAD4. BMP4-impared relaxation in mouse aorta was also ameliorated by PDGF-AA neutralizing antibody. Tail injection of Ad-Pdgfa-shRNA ameliorates endothelial dysfunction induced by Bmp4 overexpression (Ad-Bmp4) in vivo. Serum PDGF-AA was elevated in both diabetic patients and diabetic db/db mice compared with nondiabetic controls. Pdgfa-shRNA or Bmp4-shRNA adenovirus reduced serum PDGF-AA concentration in db/db mice. PDGF-AA neutralizing antibody or tail injection with Pdgfa-shRNA adenovirus improved endothelial function in aortas and mesenteric resistance arteries from db/db mice. The effect of PDGF-AA on endothelial function in mouse aorta was also inhibited by Ad-Pdgfra-shRNA to inhibit PDGFRα. The present study provides novel evidences to show that PDGF-AA impairs endothelium-dependent vasodilation and PDGF-AA mediates BMP4-induced adverse effect on endothelial cell function through SMAD1/5- and SMAD4-dependent mechanisms. Inhibition of PGDF-AA ameliorates vascular dysfunction in diabetic mice. © 2016 American Heart Association, Inc.

Cadaveric aorta implantation for aortic graft infection.

PubMed

Ali, Asad; Bahia, Sandeep S S; Ali, Tahir

2016-01-01

This case report describes a 73-year-old gentleman who underwent explantation of an infected prosthetic aorto-iliac graft and replacement with a cryopreserved thoracic and aorto-iliac allograft. The patient has been followed up a for more than a year after surgery and remains well. After elective tube graft repair of his abdominal aortic aneurysm (AAA) in 2003, he presented to our unit in 2012 in cardiac arrest as a result of a rupture of the distal graft suture line due to infection. After resuscitation he underwent aorto-bifemoral grafting using a cuff of the original aortic graft proximally. Distally the new graft was anastomosed to his common femoral arteries, with gentamicin beads left in situ. Post discharge the patient was kept under close surveillance with serial investigations including nuclear scanning, however it became apparent that his new graft was infected and that he would require aortic graft replacement, an operation with a mortality of at least 50%. The patient underwent the operation and findings confirmed a synthetic graft infection. This tube graft was explanted and a cryopreserved aorta was used to the refashion the abdominal aorta and its bifurcation. The operation required a return to theatre day one post operatively for a bleeding side branch, which was repaired. The patient went on to make a full recovery stepping down from the intensive therapy unit day 6 post operatively and went on to be discharged 32 days after his cryopreserved aorta implantation. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Increased plasma asymmetric dimethylarginine level is associated with ascending aorta dilatation: a case-control study.

PubMed

Satılmışoğlu, Muhammet Hulusi; Örnek Diker, Vesile; Taşbulak, Ömer; Diker, Mustafa; Birand, Ali; Kaya, Mehmet; İyigün, Taner; Eksik, Abdurrahman

2017-01-01

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase. We aimed to determine plasma ADMA levels in patients with ascending aorta dilatation in comparison to those without aorta dilatation, and to evaluate the diagnostic, predictive, and prognostic value of serum ADMA level for aorta dilatation. This was a cross-sectional case-control study. A total of 104 consecutive patients (female/male, 35/69; mean age, 62.75 ± 13.11 years) diagnosed with ascending aorta dilatation (≥ 4.5 cm) on echocardiography (case group), and 52 age-and gender-matched patients (female/male, 17/35; mean age, 63.44 ± 7.56 years) with normal aorta dimensions (≤ 3.8 cm) (control group) were included. Routine biochemical and haematological analysis in addition to measurement of serum ADMA level were performed. The mean diameter of ascending aorta measured on echocardiography was 4.95 ± 0.57 cm and 3.34 ± 0.36 cm in patients with aorta dilatation and those without aorta dilatation, respectively (p < 0.001). Serum ADMA level was significantly higher in patients with aorta dilatation than in the control group (1.70 ± 1.12 μmol/L vs. 0.79 ± 0.76 μmol/L, respectively, p < 0.001). There was significant positive correlation between ADMA level and aortic diameter in Spearman correlation analysis (r = 0.317, p < 0.001). In linear regression analysis, ADMA was found to be a significant independent predictor of aorta diameter (Beta = 0.26, p < 0.001). Receiver-operator characteristic curve analysis also revealed that serum ADMA cut-off level over 0.29 μmol/L predicts aorta dilatation (≥ 4.5 cm) with 94% sensitivity and 92% specificity and with high ac-curacy (area under curve: 0.786; 95% confidence interval: 0.709-0.863, p < 0.001). Serum ADMA level is diagnostic for ascending aorta dilatation with high sensitivity and specificity, and should be considered for use in clinical diagnosis of aorta dilatation.

Activation of human T cells in hypertension: Studies of Humanized Mice and Hypertensive Humans

PubMed Central

Itani, Hana A.; McMaster, William G.; Saleh, Mohamed A.; Nazarewicz, Rafal R.; Mikolajczyk, Tomasz P.; Kaszuba, Anna; Konior, Anna; Prejbisz, Aleksander; Januszewicz, Andrzej; Norlander, Allison E.; Chen, Wei; Bonami, Rachel H.; Marshall, Andrew F.; Poffenberger, Greg; Weyand, Cornelia M.; Madhur, Meena S.; Moore, Daniel J.; Harrison, David G.; Guzik, Tomasz J.

2016-01-01

Emerging evidence supports an important role for T cells in the genesis of hypertension. Because this work has predominantly been performed in experimental animals, we sought to determine whether human T cells are activated in hypertension. We employed a humanized mouse model in which the murine immune system is replaced by the human immune system. Angiotensin II increased systolic pressure to 162 mm Hg vs. 116 mm Hg for sham treated animals. Flow cytometry of thoracic lymph nodes, thoracic aorta and kidney revealed increased infiltration of human leukocytes (CD45+) and T lymphocytes (CD3+ and CD4+) in response to angiotensin II infusion. Interestingly, there was also an increase in the memory T cells (CD3+/CD45RO+) in the aortas and lymph nodes. Prevention of hypertension using hydralazine and hydrochlorothiazide prevented the accumulation of T cells in these tissues. Studies of isolated human T cells and monocytes indicated that angiotensin II had no direct effect on cytokine production by T cells or the ability of dendritic cells to drive T cell proliferation. We also observed an increase in circulating IL-17A producing CD4+ T cells and both CD4+ and CD8+ T cells that produce IFN-γ in hypertensive compared to normotensive humans. Thus, human T cells become activated and invade critical end-organ tissues in response to hypertension in a humanized mouse model. This response likely reflects the hypertensive milieu encountered in vivo and is not a direct effect of the hormone angiotensin II. PMID:27217403

Activation of Human T Cells in Hypertension: Studies of Humanized Mice and Hypertensive Humans.

PubMed

Itani, Hana A; McMaster, William G; Saleh, Mohamed A; Nazarewicz, Rafal R; Mikolajczyk, Tomasz P; Kaszuba, Anna M; Konior, Anna; Prejbisz, Aleksander; Januszewicz, Andrzej; Norlander, Allison E; Chen, Wei; Bonami, Rachel H; Marshall, Andrew F; Poffenberger, Greg; Weyand, Cornelia M; Madhur, Meena S; Moore, Daniel J; Harrison, David G; Guzik, Tomasz J

2016-07-01

Emerging evidence supports an important role for T cells in the genesis of hypertension. Because this work has predominantly been performed in experimental animals, we sought to determine whether human T cells are activated in hypertension. We used a humanized mouse model in which the murine immune system is replaced by the human immune system. Angiotensin II increased systolic pressure to 162 versus 116 mm Hg for sham-treated animals. Flow cytometry of thoracic lymph nodes, thoracic aorta, and kidney revealed increased infiltration of human leukocytes (CD45(+)) and T lymphocytes (CD3(+) and CD4(+)) in response to angiotensin II infusion. Interestingly, there was also an increase in the memory T cells (CD3(+)/CD45RO(+)) in the aortas and lymph nodes. Prevention of hypertension using hydralazine and hydrochlorothiazide prevented the accumulation of T cells in these tissues. Studies of isolated human T cells and monocytes indicated that angiotensin II had no direct effect on cytokine production by T cells or the ability of dendritic cells to drive T-cell proliferation. We also observed an increase in circulating interleukin-17A producing CD4(+) T cells and both CD4(+) and CD8(+) T cells that produce interferon-γ in hypertensive compared with normotensive humans. Thus, human T cells become activated and invade critical end-organ tissues in response to hypertension in a humanized mouse model. This response likely reflects the hypertensive milieu encountered in vivo and is not a direct effect of the hormone angiotensin II. © 2016 American Heart Association, Inc.

Elastic properties of the young aorta: ex vivo perfusion experiments in a porcine model.

PubMed

Krüger, Tobias; Grigoraviciute, Akvile; Veseli, Kujtim; Schibilsky, David; Wendel, Hans P; Schneider, Wilke; Schlensak, Christian

2015-08-01

To investigate the regional and directional compliance/distensibility of the healthy aorta. Complete fresh porcine aortas (n = 11) were perfused ex vivo under defined haemodynamic parameters using a custom-made pulse duplicator. Both circumferential and longitudinal compliance were measured optically. The pulse duplicator was able to perfuse the entire aorta with arbitrary haemodynamic parameters, generating a physiological pulse curve. Aortic compliance is pressure dependent, as we observed a linear relationship between pressure and distension in the range of 5-200 mmHg; however, above 200 mmHg, the porcine aorta behaved in an inelastic manner. Circumferential compliance was highest in the ascending aorta (24%/100 mmHg) but significantly (P < 0.05) decreased in both the arch (18%/100 mmHg) and the descending aorta (15%/100 mmHg). Longitudinal compliance was highest in the ascending aorta and clearly exceeded circumferential compliance. Compliance was significantly (P < 0.05) higher in the outer curvatures of the ascending aorta and the aortic arch compared with the compliance of the inner curvature at these locations (30%/100 vs 23%/100 mmHg in the ascending aorta and 20%/100 vs 9%/100 mmHg in the arch, respectively). Longitudinal compliance of the ascending aorta, particularly the outer curvature, is predominantly responsible for the 'Windkessel effect'. Pathological changes such as elongation and pronounced angulation of the ascending aorta increase stress on the outer curvature and may be important factors in the development of aortic dissection. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Over length quantification of the multiaxial mechanical properties of the ascending, descending and abdominal aorta using Digital Image Correlation.

PubMed

Peña, Juan A; Corral, Victoria; Martínez, Miguel A; Peña, Estefanía

2018-01-01

In this paper, we hypothesize that the biaxial mechanical properties of the aorta may be dependent on arterial location. To demonstrate any possible position-related difference, our study analyzed and compared the biaxial mechanical properties of the ascending thoracic aorta, descending thoracic aorta and infrarenal abdominal aorta stemming from the same porcine subjects, and reported values of constitutive parameters for well-known strain energy functions, showing how these mechanical properties are affected by location along the aorta. When comparing ascending thoracic aorta, descending thoracic aorta and infrarenal abdominal aorta, abdominal tissues were found to be stiffer and highly anisotropic. We found that the aorta changed from a more isotropic to a more anisotropic tissue and became progressively less compliant and stiffer with the distance to the heart. We observed substantial differences in the anisotropy parameter between aortic samples where abdominal samples were more anisotropic and nonlinear than the thoracic samples. The phenomenological model was not able to capture the passive biaxial properties of each specific porcine aorta over a wide range of biaxial deformations, showing the best prediction root mean square error ε=0.2621 for ascending thoracic samples and, especially, the worst for the infrarenal abdominal samples ε=0.3780. The micro-structured model with Bingham orientation density function was able to better predict biaxial deformations (ε=0.1372 for ascending thoracic aorta samples). The root mean square error of the micro-structural model and the micro-structured model with von Mises orientation density function were similar for all positions. Copyright © 2017 Elsevier Ltd. All rights reserved.

CANCER BIOMARKERS IN HUMAN ATHEROSCLEROTIC LESIONS: DETECTION OF DNA ADDUCTS

EPA Science Inventory

Since somatic mutations are suspected to contribute to the pathogenesis not only of cancer but also of atherosclerotic plaques, we measured DNA adducts in the smooth muscle layer of atherosclerotic lesions in abnormal aorta specimens taken at surgery from seven patients. NA adduc...

Non-invasive imaging of flow and vascular function in disease of the aorta

PubMed Central

Whitlock, Matthew C.; Hundley, W. Gregory

2015-01-01

With advancements in technology and a better understanding of human cardiovascular physiology, research as well as clinical care can go beyond dimensional anatomy offered by traditional imaging and investigate aortic functional properties and the impact disease has on this function. Linking the knowledge of the histopathological changes with the alterations in aortic function observed on noninvasive imaging results in a better understanding of disease pathophysiology. Translating this to clinical medicine, these noninvasive imaging assessments of aortic function are proving to be able to diagnosis disease, better predict risk, and assess response to therapies. This review is designed to summarize the various hemodynamic measures that can characterize the aorta, the various non-invasive techniques, and applications for various disease states. PMID:26381770

A streaming birefringence study of the flow at the junction of the aorta and the renal arteries

NASA Astrophysics Data System (ADS)

Rankin, G. W.; Sabbah, H. N.; Stein, P. D.

1989-11-01

Streaming birefringence with an organic dye (Milling Yellow) was used to investigate the flow near the junction of the renal arteries and the descending aorta in a model of human vessels. The dye concentration was adjusted to give fluid rheological properties, typical of blood. Steady and pulsatile flow were investigated at branch-to-trunk flow ratios of 0.050 0.350. The flow ratio range over which flow separation and simple secondary flows were identified during systole near the renal ostia are reported. Streaming birefringence has the advantage of allowing visualization of the entire flow field. Also, the fluid rather than suspended particles are observed. An important disadvantage, however, is that three-dimensional flows make interpretation difficult.

High prevalence of intracranial aneurysms in patients with aortic dissection or aneurysm: feasibility of extended aorta CT angiography with involvement of intracranial arteries.

PubMed

Lee, Dahye; Ahn, Sung Jun; Cho, Eun-Suk; Kim, Yong Bae; Song, Suk-Won; Jung, Woo Sang; Suh, Sang Hyun

2017-10-01

Previous studies have suggested a higher prevalence of intracranial aneurysms (IAs) in patients with aortic aneurysms (AAs). To carry out a preliminary study to evaluate the prevalence of IAs in these patients and the diagnostic feasibility of extended aorta CT angiography (CTA), including intracranial arteries as well as the aorta. We retrospectively reviewed all patients with a clinical diagnosis of AA or aortic dissection (AD) who had undergone aorta CTA as well as MR angiography, CTA, and/or DSA of the brain between 2009 and 2014. Since 2012, the extended aorta CTA protocol has been applied in these patients. Characteristics of IAs were classified with baseline clinical data. For quantitative and qualitative assessment by two independent raters, brain images obtained by extended aorta CTA and brain CTA were compared. The radiation dose of the two aorta protocols was compared. The prevalence of IA was 22.2% (35/158). All IAs were detected by extended aorta CTA, except one small aneurysm (<3 mm). The mean vascular attenuation value between brain images showed no difference (p=0.83), but the contrast-to-noise ratio was significantly lower in extended aorta CTA (p<0.001). In qualitative assessment, the interobserver agreement was substantial (k=0.79). For the radiation dose, the dose-length product of the extended aorta CTA increased with increment of the scan range (p=0.048). With a high prevalence of IAs in patients with ADs or AAs, extended aorta CTA could be used to evaluate aorta disease and IA in a single session. However, further prospective studies are needed to prove efficacy and safety of the extended aorta CTA protocol in patients with AAs or ADs. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Properties of calcium-containing microparticles formed in the process of biomineralization of the human aortic wall

NASA Astrophysics Data System (ADS)

Zlatoustova, O. Yu; Vasilev, S. V.; Rudy, A. S.

2016-08-01

The results of the study of human aortic walls, subjected to different stages of mineralization are presented. By means of scanning electron microscopy and X-ray microanalysis the morphology, elemental composition and characteristics of the mineral component localization were investigated. The key differences in the initial, intermediate and final stages of pathological mineralization of the aorta wall were identified. The data obtained may be useful in describing the mechanism of biomineral deposits formation in human body.

A patient-specific aortic valve model based on moving resistive immersed implicit surfaces.

PubMed

Fedele, Marco; Faggiano, Elena; Dedè, Luca; Quarteroni, Alfio

2017-10-01

In this paper, we propose a full computational framework to simulate the hemodynamics in the aorta including the valve. Closed and open valve surfaces, as well as the lumen aorta, are reconstructed directly from medical images using new ad hoc algorithms, allowing a patient-specific simulation. The fluid dynamics problem that accounts from the movement of the valve is solved by a new 3D-0D fluid-structure interaction model in which the valve surface is implicitly represented through level set functions, yielding, in the Navier-Stokes equations, a resistive penalization term enforcing the blood to adhere to the valve leaflets. The dynamics of the valve between its closed and open position is modeled using a reduced geometric 0D model. At the discrete level, a finite element formulation is used and the SUPG stabilization is extended to include the resistive term in the Navier-Stokes equations. Then, after time discretization, the 3D fluid and 0D valve models are coupled through a staggered approach. This computational framework, applied to a patient-specific geometry and data, allows to simulate the movement of the valve, the sharp pressure jump occurring across the leaflets, and the blood flow pattern inside the aorta.

Comparing Blast Effects on Human Torso Finite Element Model against Existing Lethality Curves

DTIC Science & Technology

2010-07-15

vertebrae, intervertebral discs, ribs, cartilage, sternum, scapula, and clavicle . The internal organs include the heart and aorta, lungs and trachea...Thoracic Vertebrae  Intervertebral Disc  Scapula  Clavicle Heritage Style Viewgraphs6 HTFEM Development Internal Organs Ten-noded tetrahedral

Raman spectroscopy imaging reveals interplay between atherosclerosis and medial calcification in the human aorta

PubMed Central

You, Amanda Y. F.; Bergholt, Mads S.; St-Pierre, Jean-Philippe; Kit-Anan, Worrapong; Pence, Isaac J.; Chester, Adrian H.; Yacoub, Magdi H.; Bertazzo, Sergio; Stevens, Molly M.

2017-01-01

Medial calcification in the human aorta accumulates during aging and is known to be aggravated in several diseases. Atherosclerosis, another major cause of cardiovascular calcification, shares some common aggravators. However, the mechanisms of cardiovascular calcification remain poorly understood. To elucidate the relationship between medial aortic calcification and atherosclerosis, we characterized the cross-sectional distributions of the predominant minerals in aortic tissue, apatite and whitlockite, and the associated extracellular matrix. We also compared the cellular changes between atherosclerotic and nonatherosclerotic human aortic tissues. This was achieved through the development of Raman spectroscopy imaging methods that adapted algorithms to distinguish between the major biomolecules present within these tissues. We present a relationship between apatite, cholesterol, and triglyceride in atherosclerosis, with the relative amount of all molecules concurrently increased in the atherosclerotic plaque. Further, the increase in apatite was disproportionately large in relation to whitlockite in the aortic media directly underlying a plaque, indicating that apatite is more pathologically significant in atherosclerosis-aggravated medial calcification. We also discovered a reduction of β-carotene in the whole aortic intima, including a plaque in atherosclerotic aortic tissues compared to nonatherosclerotic tissues. This unprecedented biomolecular characterization of the aortic tissue furthers our understanding of pathological and physiological cardiovascular calcification events in humans. PMID:29226241

Regional and directional compliance of the healthy aorta: an ex vivo study in a porcine model.

PubMed

Krüger, Tobias; Veseli, Kujtim; Lausberg, Henning; Vöhringer, Luise; Schneider, Wilke; Schlensak, Christian

2016-07-01

To gain differential knowledge about the physiological compliance and wall strength of the different regions of the aorta, including the ascending aorta, arch and descending aorta in both the circumferential and longitudinal directions, and to generate a hypothesis on the pathophysiological mechanisms that lead to Type A aortic dissection. Fresh tissue specimens from 22 ex vivo porcine aortas were analysed on a tensile tester. Regional and directional compliance, failure stress and failure strain were recorded. Aortic compliance appeared as a linear function of the natural logarithm (ln) of wall stress. Compliance significantly decreased along the length of the aorta. In the ascending aorta, longitudinal compliance significantly (P = 0.003) exceeded circumferential compliance, and the outer curvature was more compliant than the inner curvature (P = 0.03). In the descending aorta, this relationship is reversed: the circumferential compliance exceeded the longitudinal compliance, and the outer aspect was more compliant (P = 0.003). The median circumferential failure stress of all aortic segments was in the range of 2000-2750 kPa, whereas the longitudinal failure stress in the ascending aorta and the arch had values of 750-1000 kPa, which were significantly lower (P < 0.05). Surprisingly, the longitudinal failure stress of the inner aspect of the descending aorta was extraordinarily high (2000 kPa). Failure strain, similar to compliance, was highest in the ascending aorta and decreased along the aorta. The aorta appears to be a complex organ with distinct regional and directional differences in compliance and wall strength that is designed to effectively absorb the kinetic energy of cardiac systole and to cushion the momentum of systolic impact. Under normotensive conditions and a preconditioned physiological morphology, the aortic wall works in the steep part of the logarithmic strain-stress function; under hypertensive conditions and pathological morphology, the wall reacts in an non-compliant manner. The high longitudinal compliance and low failure stress of the ascending aorta and subsequent pathological changes may be the main determinants of the recurrent patho-anatomy of Type A aortic dissection. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Regional and directional compliance of the healthy aorta: an ex vivo study in a porcine model†

PubMed Central

Krüger, Tobias; Veseli, Kujtim; Lausberg, Henning; Vöhringer, Luise; Schneider, Wilke; Schlensak, Christian

2016-01-01

OBJECTIVES To gain differential knowledge about the physiological compliance and wall strength of the different regions of the aorta, including the ascending aorta, arch and descending aorta in both the circumferential and longitudinal directions, and to generate a hypothesis on the pathophysiological mechanisms that lead to Type A aortic dissection. METHODS Fresh tissue specimens from 22 ex vivo porcine aortas were analysed on a tensile tester. Regional and directional compliance, failure stress and failure strain were recorded. RESULTS Aortic compliance appeared as a linear function of the natural logarithm (ln) of wall stress. Compliance significantly decreased along the length of the aorta. In the ascending aorta, longitudinal compliance significantly (P = 0.003) exceeded circumferential compliance, and the outer curvature was more compliant than the inner curvature (P = 0.03). In the descending aorta, this relationship is reversed: the circumferential compliance exceeded the longitudinal compliance, and the outer aspect was more compliant (P = 0.003). The median circumferential failure stress of all aortic segments was in the range of 2000–2750 kPa, whereas the longitudinal failure stress in the ascending aorta and the arch had values of 750–1000 kPa, which were significantly lower (P < 0.05). Surprisingly, the longitudinal failure stress of the inner aspect of the descending aorta was extraordinarily high (2000 kPa). Failure strain, similar to compliance, was highest in the ascending aorta and decreased along the aorta. CONCLUSION The aorta appears to be a complex organ with distinct regional and directional differences in compliance and wall strength that is designed to effectively absorb the kinetic energy of cardiac systole and to cushion the momentum of systolic impact. Under normotensive conditions and a preconditioned physiological morphology, the aortic wall works in the steep part of the logarithmic strain–stress function; under hypertensive conditions and pathological morphology, the wall reacts in an non-compliant manner. The high longitudinal compliance and low failure stress of the ascending aorta and subsequent pathological changes may be the main determinants of the recurrent patho-anatomy of Type A aortic dissection. PMID:26993474

Techniques of imaging of the aorta and its first order branches by endoscopic ultrasound (with videos)

PubMed Central

Sharma, Malay; Rai, Praveer; Mehta, Varun; Rameshbabu, C. S.

2015-01-01

Endoscopic ultrasonography (EUS) is a useful modality for imaging of the blood vessels of the mediastinum and abdomen. The aorta acts as an important home base during EUS imaging. The aorta and its branches are accessible by standard angiographic methods, but endosonography also provides a unique opportunity to evaluate the aorta and its branches. This article describes the techniques of imaging of different part of the aorta by EUS. PMID:26020043

Lipoprotein-associated phospholipase A(2), platelet-activating factor acetylhydrolase, is expressed by macrophages in human and rabbit atherosclerotic lesions.

PubMed

Häkkinen, T; Luoma, J S; Hiltunen, M O; Macphee, C H; Milliner, K J; Patel, L; Rice, S Q; Tew, D G; Karkola, K; Ylä-Herttuala, S

1999-12-01

We studied the expression of lipoprotein-associated phospholipase A(2) (Lp-PLA(2)), an enzyme capable of hydrolyzing platelet-activating factor (PAF), PAF-like phospholipids, and polar-modified phosphatidylcholines, in human and rabbit atherosclerotic lesions. Oxidative modification of low-density lipoprotein, which plays an important role in atherogenesis, generates biologically active PAF-like modified phospholipid derivatives with polar fatty acid chains. PAF is known to have a potent proinflammatory activity and is inactivated by its hydrolysis. On the other hand, lysophosphatidylcholine and oxidized fatty acids released from oxidized low-density lipoprotein as a result of Lp-PLA(2) activity are thought to be involved in the progression of atherosclerosis. Using combined in situ hybridization and immunocytochemistry, we detected Lp-PLA(2) mRNA and protein in macrophages in both human and rabbit atherosclerotic lesions. Reverse transcriptase-polymerase chain reaction analysis indicated an increased expression of Lp-PLA(2) mRNA in human atherosclerotic lesions. In addition, approximately 6-fold higher Lp-PLA(2) activity was detected in atherosclerotic aortas of Watanabe heritable hyperlipidemic rabbits compared with normal aortas from control rabbits. It is concluded that (1) macrophages in both human and rabbit atherosclerotic lesions express Lp-PLA(2), which could cleave any oxidatively modified phosphatidylcholine present in the lesion area, and (2) modulation of Lp-PLA(2) activity could lead to antiatherogenic effects in the vessel wall.

Structural and functional characterization of the contractile aorta and associated hemocytes of the mosquito Anopheles gambiae.

PubMed

Sigle, Leah T; Hillyer, Julián F

2018-06-22

The primary pump of the circulatory system of insects is a dorsal vessel that traverses the length of the insect. The anterior portion, located in the head, neck and thorax, is the aorta, and the posterior portion, located in the abdomen, is the heart. Here, we characterize the structure and function of the aorta and conical chamber of the mosquito, Anopheles gambiae The aorta begins in the head with an excurrent opening located above the dorsal pharyngeal plate and ends at the thoraco-abdominal junction where it joins the conical chamber of the heart. The aorta lacks ostia, and based on the diameter of the vessel as well as the density and helical orientation of muscle, consists of three regions: the anterior aorta, the bulbous chamber, and the posterior aorta. The aorta contracts in the anterograde direction, but these contractions are independent of heart contractions and do not play a major role in hemolymph propulsion. Intravital imaging of the venous channels, the first abdominal segment and the neck revealed that hemolymph only travels through the aorta in the anterograde direction, and does so only during periods of anterograde heart flow. Furthermore, hemolymph only enters the thoraco-abdominal ostia of the conical chamber when the heart contracts in the retrograde direction, propelling this hemolymph to the posterior of the body. Finally, very few hemocytes associate with the aorta, and unlike what is seen in the periostial regions of the heart, infection does not induce the aggregation of hemocytes on the aorta. © 2018. Published by The Company of Biologists Ltd.

Apico-brachiocephalic artery bypass for aortic stenosis with porcelain aorta.

PubMed

Shimizu, Shuji; Nakai, Mikizo; Itoh, Atsushi; Yoshizumi, Ko; Ochi, Yoshiki; Okada, Masahiro; Sano, Shunji

2010-02-01

Apicoaortic bypass for left ventricular outflow tract obstruction has been performed with acceptable mid-term mortality. However, sometimes it is difficult to anastomose the distal end of the conduit to the calcified descending aorta in patients with a porcelain aorta. We report an aortic non-touch modification of the apicoaortic bypass in an 80-year-old woman with valvular aortic stenosis and a porcelain aorta extending from the ascending to abdominal aorta. We performed apico-brachiocephalic artery bypass under circulatory arrest with deep hypothermia. This procedure may become a useful surgical option for patients with a severe porcelain aorta. 2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Axial nonuniformity of geometric and mechanical properties of mouse aorta is increased during postnatal growth.

PubMed

Huang, Yi; Guo, Xiaomei; Kassab, Ghassan S

2006-02-01

The hemodynamic conditions of aorta are relatively uniform prenatally and become more heterogeneous postnatally. Our objective was to quantify the heterogeneity of geometry and mechanical properties during growth and development. To accomplish this objective, we obtained a systematic set of data on the geometry and mechanical properties along the length of mouse aorta during postnatal development. C57BL/6 mice of ages 1-33 days were studied. The ascending aorta was cannulated in situ and preconditioned with several cyclic changes in pressure. We investigated the axial variations of geometry (diameter and length) and mechanical properties (stress-stain relation, elastic modulus and compliance) of the mouse aorta from the aortic valve to the common iliac. Our results show that the arterial blood pressure of mice increased from approximately 30 to 80 mmHg during the first 2 wk of life. The stretch ratio, diameter, wall (intima-media) thickness, and total lumen volume of mouse aorta increased with age. The aorta was transformed from a cylindrical tube at birth to a tapered structure during growth. Furthermore, we found the mechanical properties were fairly uniform along the length of the aorta at birth and become more nonuniform with age. We conclude that the rapid change of blood pressure and blood flow after birth alter the geometric and mechanical properties differentially along the length of the aorta. Hence, the axial nonuniformity of the aorta increases as the organ becomes more specialized during growth and development.

Contribution of elastin and collagen to the inflation response of the pig thoracic aorta: assessing elastin's role in mechanical homeostasis.

PubMed

Lillie, M A; Armstrong, T E; Gérard, S G; Shadwick, R E; Gosline, J M

2012-08-09

This study was undertaken to understand elastin's role in the mechanical homeostasis of the arterial wall. The mechanical properties of elastin vary along the aorta, and we hypothesized this maintained a uniform mechanical environment for the elastin, despite regional variation in loading. Elastin's physiological loading was determined by comparing the inflation response of intact and autoclave purified elastin aortas from the proximal and distal thoracic aorta. Elastin's stretch and stress depend on collagen recruitment. Collagen recruitment started in the proximal aorta at systolic pressures (13.3 to 14.6 kPa) and in the distal at sub-diastolic pressures (9.3 to 10.6 kPa). In the proximal aorta collagen did not contribute significantly to the stress or stiffness, indicating that elastin determined the vessel properties. In the distal aorta, the circumferential incremental modulus was 70% higher than in the proximal aorta, half of which (37%) was due to a stiffening of the elastin. Compared to the elastin tissue in the proximal aorta, the distal elastin suffered higher physiological circumferential stretch (29%, P=0.03), circumferential stress (39%, P=0.02), and circumferential stiffness (37%, P=0.006). Elastin's physiological axial stresses were also higher (67%, P=0.003). These findings do not support the hypothesis that the loading on elastin is constant along the aorta as we expected from homeostasis. Copyright © 2012 Elsevier Ltd. All rights reserved.

Attenuation of the anti-contractile effect of cooling in the rat aorta by perivascular adipose tissue.

PubMed

Rafique, Y; AlBader, M; Oriowo, M

2017-09-01

In addition to providing mechanical support for blood vessels, the perivascular adipose tissue (PVAT) secretes a number of vasoactive substances and exerts an anticontractile effect. The main objective of this study was to find out whether the anticontractile effect of cooling in the rat aorta is affected by PVAT. Our hypothesis was that PVAT would enhance the anticontractile effect of cooling in the rat aorta. Aorta segments, with or without PVAT, were used in this investigation. Cumulative concentration-response curves were established for phenylephrine at 37°C or 24°C. Phenylephrine (10 -9 M - 10 -5 M) induced concentration-dependent contractions of aorta segments with or without PVAT at 37°C. The maximum response, but not pD 2 value, was reduced in aorta segments with PVAT. Cooling the tissues to 24 °C resulted in a significant reduction in the maximum response in aorta segments without PVAT with no change in pD 2 values. However, the anticontractile effect of cooling was attenuated in the presence of PVAT with no significant (p > 0.05) change in either the maximum response or pD 2 value. L-NAME potentiated PE-induced contractions and this was greater in aorta segments without PVAT at both temperatures. The expression of eNOS protein and basal tissue level of nitric oxide (NO) were greater in aorta segments with PVAT at both temperatures. However, PE significantly increased tissue levels of NO only in aorta segments without PVAT. We concluded that PVAT-induced loss of anticontractile effect of cooling against PE-induced contractions could be due to impaired generation of NO in aorta segments with PVAT. © 2017 John Wiley & Sons Ltd.

Age-Related Vascular Changes Affect Turbulence in Aortic Blood Flow

PubMed Central

Ha, Hojin; Ziegler, Magnus; Welander, Martin; Bjarnegård, Niclas; Carlhäll, Carl-Johan; Lindenberger, Marcus; Länne, Toste; Ebbers, Tino; Dyverfeldt, Petter

2018-01-01

Turbulent blood flow is implicated in the pathogenesis of several aortic diseases but the extent and degree of turbulent blood flow in the normal aorta is unknown. We aimed to quantify the extent and degree of turbulece in the normal aorta and to assess whether age impacts the degree of turbulence. 22 young normal males (23.7 ± 3.0 y.o.) and 20 old normal males (70.9 ± 3.5 y.o.) were examined using four dimensional flow magnetic resonance imaging (4D Flow MRI) to quantify the turbulent kinetic energy (TKE), a measure of the intensity of turbulence, in the aorta. All healthy subjects developed turbulent flow in the aorta, with total TKE of 3–19 mJ. The overall degree of turbulence in the entire aorta was similar between the groups, although the old subjects had about 73% more total TKE in the ascending aorta compared to the young subjects (young = 3.7 ± 1.8 mJ, old = 6.4 ± 2.4 mJ, p < 0.001). This increase in ascending aorta TKE in old subjects was associated with age-related dilation of the ascending aorta which increases the volume available for turbulence development. Conversely, age-related dilation of the descending and abdominal aorta decreased the average flow velocity and suppressed the development of turbulence. In conclusion, turbulent blood flow develops in the aorta of normal subjects and is impacted by age-related geometric changes. Non-invasive assessment enables the determination of normal levels of turbulent flow in the aorta which is a prerequisite for understanding the role of turbulence in the pathophysiology of cardiovascular disease. PMID:29422871

Aortic angiography

MedlinePlus

Angiography - aorta; Aortography; Abdominal aorta angiogram; Aortic arteriogram; Aneurysm - aortic arteriogram ... this needle. The catheter is moved into the aorta. The doctor can see live images of the ...

Search for Rare Copy-Number Variants in Congenital Heart Defects Identifies Novel Candidate Genes and a Potential Role for FOXC1 in Patients With Coarctation of the Aorta.

PubMed

Sanchez-Castro, Marta; Eldjouzi, Hadja; Charpentier, Eric; Busson, Pierre-François; Hauet, Quentin; Lindenbaum, Pierre; Delasalle-Guyomarch, Béatrice; Baudry, Adrien; Pichon, Olivier; Pascal, Cécile; Lefort, Bruno; Bajolle, Fanny; Pezard, Philippe; Schott, Jean-Jacques; Dina, Christian; Redon, Richard; Gournay, Véronique; Bonnet, Damien; Le Caignec, Cédric

2016-02-01

Congenital heart defects are the most frequent malformations among newborns and a frequent cause of morbidity and mortality. Although genetic variation contributes to congenital heart defects, their precise molecular bases remain unknown in the majority of patients. We analyzed, by high-resolution array comparative genomic hybridization, 316 children with sporadic, nonsyndromic congenital heart defects, including 76 coarctation of the aorta, 159 transposition of the great arteries, and 81 tetralogy of Fallot, as well as their unaffected parents. We identified by array comparative genomic hybridization, and validated by quantitative real-time polymerase chain reaction, 71 rare de novo (n=8) or inherited (n=63) copy-number variants (CNVs; 50 duplications and 21 deletions) in patients. We identified 113 candidate genes for congenital heart defects within these CNVs, including BTRC, CHRNB3, CSRP2BP, ERBB2, ERMARD, GLIS3, PLN, PTPRJ, RLN3, and TCTE3. No de novo CNVs were identified in patients with transposition of the great arteries in contrast to coarctation of the aorta and tetralogy of Fallot (P=0.002; Fisher exact test). A search for transcription factor binding sites showed that 93% of the rare CNVs identified in patients with coarctation of the aorta contained at least 1 gene with FOXC1-binding sites. This significant enrichment (P<0.0001; permutation test) was not observed for the CNVs identified in patients with transposition of the great arteries and tetralogy of Fallot. We hypothesize that these CNVs may alter the expression of genes regulated by FOXC1. Foxc1 belongs to the forkhead transcription factors family, which plays a critical role in cardiovascular development in mice. These data suggest that deregulation of FOXC1 or its downstream genes play a major role in the pathogenesis of coarctation of the aorta in humans. © 2015 American Heart Association, Inc.

Mechanical factors direct mouse aortic remodelling during early maturation

PubMed Central

Le, Victoria P.; Cheng, Jeffrey K.; Kim, Jungsil; Staiculescu, Marius C.; Ficker, Shawn W.; Sheth, Saahil C.; Bhayani, Siddharth A.; Mecham, Robert P.; Yanagisawa, Hiromi; Wagenseil, Jessica E.

2015-01-01

Numerous diseases have been linked to genetic mutations that lead to reduced amounts or disorganization of arterial elastic fibres. Previous work has shown that mice with reduced amounts of elastin (Eln+/−) are able to live a normal lifespan through cardiovascular adaptations, including changes in haemodynamic stresses, arterial geometry and arterial wall mechanics. It is not known if the timeline and presence of these adaptations are consistent in other mouse models of elastic fibre disease, such as those caused by the absence of fibulin-5 expression (Fbln5−/−). Adult Fbln5−/− mice have disorganized elastic fibres, decreased arterial compliance and high blood pressure. We examined mechanical behaviour of the aorta in Fbln5−/− mice through early maturation when the elastic fibres are being assembled. We found that the physiologic circumferential stretch, stress and modulus of Fbln5−/− aorta are maintained near wild-type levels. Constitutive modelling suggests that elastin contributions to the total stress are decreased, whereas collagen contributions are increased. Understanding how collagen fibre structure and mechanics compensate for defective elastic fibres to meet the mechanical requirements of the maturing aorta may help to better understand arterial remodelling in human elastinopathies. PMID:25652465

Surgical access via right thoracotomy facilitates tricuspid valve surgery in sheep

PubMed Central

Bothe, Wolfgang; Diab, Mahmoud; Ostermann, Romanus; Schwarzer, Michael; Woelfel, Luisa; Bischoff, Sabine; Schubert, Harald

2017-01-01

In quadrupeds, the three-dimensional orientation of the heart with respect to the thorax is fundamentally different from that in humans. In this study, we assessed the best surgical approach to the tricuspid valve in sheep. Firstly, different surgical access sites to the tricuspid valve were tested in sheep cadavers, the anatomy was analyzed, and the optimal surgical approach to the tricuspid valve was determined. Secondly - along with cardiopulmonary bypass and cardioplegic arrest -the chosen approach was tested in six adult sheep in vivo. Anatomical analyses revealed that a left thoracotomy provided optimal access to the aorta and left heart. However, visualization of the right heart was significantly impaired. In contrast, a right thoracotomy provided good access to the right heart, but the ascending aorta was difficult to approach. Therefore, in the in vivo studies, arterial cannulation was performed through a carotid (n = 4) or femoral (n = 2) artery. In conclusion, a right-sided thoracotomy allows good visualization of all components of the tricuspid valve complex in sheep, but not of the ascending aorta. Consequently, peripheral vessels are preferred for arterial cannulation. This work may stimulate the investigation of pathomechanisms and/or novel treatment options for tricuspid valve pathologies. PMID:27456775

High blood pressure - infants

MedlinePlus

... birth (congenital). Common examples include: Coarctation of the aorta (narrowing of the large blood vessel of the heart called the aorta) Patent ductus arteriosus (blood vessel between the aorta ...

Molecular organization of the cholesteryl ester droplets in the fatty streaks of human aorta.

PubMed Central

Engelman, D M; Hillman, G M

1976-01-01

X-ray diffraction patterns from human arterial specimens containing atherosclerotic fatty streak lesions exhibited a single sharp reflection, corresponding to a structural spacing of about 35 A. Specimens without lesions did not. When specimens with fatty streaks were heated, an order-to-disorder phase transition was revealed by the disappearance of the sharp reflection. The transition was thermally reversible and its temperature varied from aorta to aorta over a range from 28 degrees to 42 degrees C. Since cholesteryl ester droplets are a major component of fatty streaks, comparison studies were made of the diffraction behavior from pure cholesteryl esters. We found that the diffraction patterns of the fatty streak material could be accounted for by the organization of the cholesteryl esters into a liquid-crystalline smectic phase that melts from the smectic to a less ordered phase upon heating. When combined with the conclusions of others from polarized light microscopy, our study shows that a droplet in the smectic phase has well-defined concentric layers of lipid molecules. In each layer, the long axes of the molecules have a net radial orientation with respect to the droplet, but the side-to-side organization is disordered. We suggest that the accessibility of portions of the lipids for specific binding to enzymes or transport proteins may be restricted when they are in the smectic state, and that exchange of lipids with surrounding membranes or other potential binding sites may likewise be inhibited. The restriction in the smectic phase should be greater than in the less ordered phases that exist at higher temperatures. Images PMID:965500

Identification of Reference Genes for Quantitative Real Time PCR Assays in Aortic Tissue of Syrian Hamsters with Bicuspid Aortic Valve

PubMed Central

Rueda-Martínez, Carmen; Fernández, M. Carmen; Soto-Navarrete, María Teresa; Jiménez-Navarro, Manuel; Durán, Ana Carmen; Fernández, Borja

2016-01-01

Bicuspid aortic valve (BAV) is the most frequent congenital cardiac malformation in humans, and appears frequently associated with dilatation of the ascending aorta. This association is likely the result of a common aetiology. Currently, a Syrian hamster strain with a relatively high (∼40%) incidence of BAV constitutes the only spontaneous animal model of BAV disease. The characterization of molecular alterations in the aorta of hamsters with BAV may serve to identify pathophysiological mechanisms and molecular markers of disease in humans. In this report, we evaluate the expression of ten candidate reference genes in aortic tissue of hamsters in order to identify housekeeping genes for normalization using quantitative real time PCR (RT-qPCR) assays. A total of 51 adult (180–240 days old) and 56 old (300–440 days old) animals were used. They belonged to a control strain of hamsters with normal, tricuspid aortic valve (TAV; n = 30), or to the affected strain of hamsters with TAV (n = 45) or BAV (n = 32). The expression stability of the candidate reference genes was determined by RT-qPCR using three statistical algorithms, GeNorm, NormFinder and Bestkeeper. The expression analyses showed that the most stable reference genes for the three algorithms employed were Cdkn1β, G3pdh and Polr2a. We propose the use of Cdkn1β, or both Cdkn1β and G3pdh as reference genes for mRNA expression analyses in Syrian hamster aorta. PMID:27711171

Identification of Reference Genes for Quantitative Real Time PCR Assays in Aortic Tissue of Syrian Hamsters with Bicuspid Aortic Valve.

PubMed

Rueda-Martínez, Carmen; Fernández, M Carmen; Soto-Navarrete, María Teresa; Jiménez-Navarro, Manuel; Durán, Ana Carmen; Fernández, Borja

2016-01-01

Bicuspid aortic valve (BAV) is the most frequent congenital cardiac malformation in humans, and appears frequently associated with dilatation of the ascending aorta. This association is likely the result of a common aetiology. Currently, a Syrian hamster strain with a relatively high (∼40%) incidence of BAV constitutes the only spontaneous animal model of BAV disease. The characterization of molecular alterations in the aorta of hamsters with BAV may serve to identify pathophysiological mechanisms and molecular markers of disease in humans. In this report, we evaluate the expression of ten candidate reference genes in aortic tissue of hamsters in order to identify housekeeping genes for normalization using quantitative real time PCR (RT-qPCR) assays. A total of 51 adult (180-240 days old) and 56 old (300-440 days old) animals were used. They belonged to a control strain of hamsters with normal, tricuspid aortic valve (TAV; n = 30), or to the affected strain of hamsters with TAV (n = 45) or BAV (n = 32). The expression stability of the candidate reference genes was determined by RT-qPCR using three statistical algorithms, GeNorm, NormFinder and Bestkeeper. The expression analyses showed that the most stable reference genes for the three algorithms employed were Cdkn1β, G3pdh and Polr2a. We propose the use of Cdkn1β, or both Cdkn1β and G3pdh as reference genes for mRNA expression analyses in Syrian hamster aorta.

Iterative Otsu's method for OCT improved delineation in the aorta wall

NASA Astrophysics Data System (ADS)

Alonso, Daniel; Real, Eusebio; Val-Bernal, José F.; Revuelta, José M.; Pontón, Alejandro; Calvo Díez, Marta; Mayorga, Marta; López-Higuera, José M.; Conde, Olga M.

2015-07-01

Degradation of human ascending thoracic aorta has been visualized with Optical Coherence Tomography (OCT). OCT images of the vessel wall exhibit structural degradation in the media layer of the artery, being this disorder the final trigger of the pathology. The degeneration in the vessel wall appears as low-reflectivity areas due to different optical properties of acidic polysaccharides and mucopolysaccharides in contrast with typical ordered structure of smooth muscle cells, elastin and collagen fibers. An OCT dimension indicator of wall degradation can be generated upon the spatial quantification of the extension of degraded areas in a similar way as conventional histopathology. This proposed OCT marker can offer in the future a real-time clinical perception of the vessel status to help cardiovascular surgeons in vessel repair interventions. However, the delineation of degraded areas on the B-scan image from OCT is sometimes difficult due to presence of speckle noise, variable signal to noise ratio (SNR) conditions on the measurement process, etc. Degraded areas can be delimited by basic thresholding techniques taking advantage of disorders evidences in B-scan images, but this delineation is not optimum in the aorta samples and requires complex additional processing stages. This work proposes an optimized delineation of degraded areas within the aorta wall, robust to noisy environments, based on the iterative application of Otsu's thresholding method. Results improve the delineation of wall anomalies compared with the simple application of the algorithm. Achievements could be also transferred to other clinical scenarios: carotid arteries, aorto-iliac or ilio-femoral sections, intracranial, etc.

An experimental cadaveric study for a better understanding of blunt traumatic aortic rupture.

PubMed

Baqué, Patrick; Serre, Thierry; Cheynel, Nicolas; Arnoux, Pierre-Jean; Thollon, Lionel; Behr, Michel; Masson, Catherine; Delotte, Jérôme; Berdah, Stéphane-Victor; Brunet, Christian

2006-09-01

Blunt traumatic aortic rupture (BTAR) is a common catastrophic injury leading to death. Considerable uncertainty remains regarding the pathogenic cause. This study examines the comportment of the heart and the aorta during a frontal deceleration. Accelerometers were placed in the right ventricle of the heart, the aorta, the sternum, and the spine of six trunks removed from human cadavers. Different vertical decelerations were applied to cadavers and the relative motion of these organs was studied (19 tests). The deceleration recorded in the isthmus of the aorta was always higher that the one recorded in the heart (p < 0.05). The difference of deceleration was 17% and increased with the speed's fall (extremes 5-25%). There was no significant difference of deceleration between the bony structures of the thorax. These results experimentally demonstrate for the first time that the fundamental mechanism of BTAR is sudden stretching of the isthmus of the aorta. Four mechanisms are suspected to explain the location of the rupture: two hemodynamic mechanism (sudden increase of intravascular pressure and the water-hammer effect), and two physical mechanisms (sudden stretching of the isthmus and the osseous pinch). A greater understanding of the mechanism of this injury could improve vehicle safety leading to a reduction in its incidence and severity. Future work in this area should include the creation of an inclusive, dynamic model of computer-based modeling systems. This study provides for the first time physical demonstration and quantification of the stretching of the isthmus, leading to a computerized model of BTAR.

High-pitch dual-source CT angiography without ECG-gating for imaging the whole aorta: intraindividual comparison with standard pitch single-source technique without ECG-gating

PubMed Central

Manna, Carmelinda; Silva, Mario; Cobelli, Rocco; Poggesi, Sara; Rossi, Cristina; Sverzellati, Nicola

2017-01-01

PURPOSE We aimed to perform intraindividual comparison of computed tomography (CT) parameters, image quality, and radiation exposure between standard CT angiography (CTA) and high-pitch dual source (DS)-CTA, in subjects undergoing serial CTA of thoracoabdominal aorta. METHODS Eighteen subjects with thoracoabdominal CTA by standard technique and high-pitch DS-CTA technique within 6 months of each other were retrieved for intraindividual comparison of image quality in thoracic and abdominal aorta. Quantitative analysis was performed by comparison of mean aortic attenuation, noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). Qualitative analysis was performed by visual assessment of motion artifacts and diagnostic confidence. Radiation exposure was quantified by effective dose. Image quality was apportioned to radiation exposure by means of figure of merit. RESULTS Mean aortic attenuation and noise were higher in high-pitch DS-CTA of thoracoabdominal aorta, whereas SNR and CNR were similar in thoracic aorta and significantly lower in high-pitch DS-CTA of abdominal aorta (P = 0.024 and P = 0.016). High-pitch DS-CTA was significantly better in the first segment of thoracic aorta. Effective dose was reduced by 72% in high-pitch DS-CTA. CONCLUSION High-pitch DS-CTA without electrocardiography-gating is an effective technique for imaging aorta with very low radiation exposure and with significant reduction of motion artifacts in ascending aorta; however, the overall quality of high-pitch DS-CTA in abdominal aorta is lower than standard CTA. PMID:28703104

In vitro evaluation of the effect of aortic compliance on pediatric intra-aortic balloon pumping.

PubMed

Minich, L L; Tani, L Y; Hawkins, J A; Bartkowiak, R R; Royall, M L; Pantalos, G M

2001-04-01

OBJECTIVES: To evaluate the effect of aortic compliance on pediatric intra-aortic balloon pumping (IABP). DESIGN: In vitro study using a mechanical model of the pediatric left heart circulation. SETTING: Cardiovascular fluid dynamics research laboratory. SUBJECT: Pulsatile flow system simulating the pediatric left heart circulation and two different aortas with compliances comparable to those of the pediatric aorta (0.12 and 0.07 mL/mm Hg). INTERVENTIONS: Measurements were made at a baseline peak aortic flow of 4 L/min, at simulated shock (1.7 L/min), and with 1:1 IABP (rates, 130 and 150 bpm; balloon volumes, 2.5 and 5.0 mL). MEASUREMENTS AND MAIN RESULTS: Peak flow rates were measured in the ascending aorta, coronary arterial system, and brachiocephalic arterial systems. Aortic pressure was measured in the ascending aorta. For both aortas (0.12 and 0.07 mL/mm Hg), IABP resulted in diastolic augmentation (38 +/- 8 and 43 +/- 16 mm Hg) and afterload reduction (4 +/- 2 and 6 +/- 3 mm Hg). For both aortas, compared to shock, IABP resulted in significant increases in coronary arterial and brachiocephalic arterial flow and aortic pressure for both aortas. Aortic flow significantly increased only in the less-compliant aorta. CONCLUSIONS: In a laboratory model of pediatric left heart circulation, IABP results in diastolic augmentation, afterload reduction, and improved hemodynamics, even in aortas of greater compliance.

Heartbeat

MedlinePlus

... The last of the great vessels is the aorta, the body's largest artery, which transports oxygen-rich ... through the aortic semilunar valves and into the aorta. From here, the aorta and its branches carry ...

Glossary

MedlinePlus

... Donors Corporate Sponsors Donor Privacy Policy Glossary Abdominal aorta Portion of the aorta within the abdominal cavity, ... Any substance, which inhibits clotting of the blood. Aorta Largest artery in the body originating at the ...

Rat aorta as a pharmacological tool for in vitro and in vivo studies.

PubMed

Rameshrad, Maryam; Babaei, Hossein; Azarmi, Yadollah; Fouladi, Daniel Fadaei

2016-01-15

Rat aorta assay provides a low cost and rapid platform, especially for preclinical in vivo models. The signaling pathways of the analog on the vessels could be evaluated separately on the endothelium or smooth muscle cells by rings of the rat aorta in vitro. The rat aorta is used for angiogenesis modeling to integrate the benefits of the both in vivo and in vitro models. These explain the importance and usage of rat aorta in researches. Furthermore, about 4503 articles have been published with the key word "rat aorta" in title or abstract from 1955 until the end of 2013 in Medline. In this review, these articles were organized into two main categories: in vivo and in vitro studies. The in vitro section focused on the rat aorta model, as a tool for evaluate the mechanism of vasodilation, vasoconstriction and angiogenesis. In the in vivo section, the most important usage of this tissue was evaluated. Also, the vasotonic signaling pathways in the vessel are explained briefly and some rat aorta applications in vitro and in vivo have been discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

Coarctation of the Aorta

MedlinePlus

... aorta may include: Narrowing of the aortic valve (aortic stenosis) High blood pressure Stroke Enlargement in a section of the wall of the aorta (aneurysm) Aortic rupture or tear (dissection) Premature coronary ...

Treatment of symptomatic coral reef aorta with an uncovered stent graft.

PubMed

Bosanquet, D C; Wood, A; Williams, I M

2015-10-01

Coral reef aorta is a rare condition characterised by extreme calcific growths affecting the juxta and suprarenal aorta. It can cause symptoms due to visceral ischaemia, lower limb hypoperfusion, and distal embolisation. We present a case of a 61-year-old man with unresponsive hypertension, who was found to have an occluded right renal artery, and an extensive coral reef aorta with a marked pressure gradient across the lesion. Renal hypoperfusion secondary to aortic coral reef aorta was thought to be the cause for his hypertension. Endovascular placement of a balloon expandable uncovered stent resolved his hypertension within one month, with no adverse effects noted at subsequent follow-up. Endovascular treatment of coral reef aorta is technically possible and avoids a major vascular procedure. © The Author(s) 2014.

Performance of Junctional Tourniquets in Normal Human Volunteers

DTIC Science & Technology

2014-12-01

cross-hatch marks, and the left side was the zero point that anchored the line. The subject made a cross mark on the line, which went from the left...the ankle . The AAJT, which aims to compress the distal aorta and adjacent blood vessels when used over the umbilicus where there appears to be no

[Anesthesia for total and descending aorta replacement and aortic valve replacement for post-repair aneurysm of coarctation of aorta and aortic stenosis].

PubMed

Furuichi, Yuko; Shimizu, Jun; Sakamoto, Atsuhiro

2012-04-01

We experienced anesthesia for total arch and descending aorta replacement and aortic valve replacement for post-repair aneurysm of coarctation of aorta and aortic stenosis. Because there was possibility that post coarctectomy syndrome would occur after repair of coarctation of aorta, administration of depressor that acts on renin-angiotensin-aldosterone and careful observation were needed postoperatively. In consideration of the development of collateral vessels, preoperative imaging evaluation was added and operative method in cardiopulmonary bypass was adjusted. Careful preoperative evaluation is very important in cardiac anesthesia.

Isolated Anomalous Origin of Left Pulmonary Artery From the Descending Aorta: An Embryologic Ambiguity.

PubMed

Gnanappa, Ganesh Kumar; Laohachai, Karina; Orr, Yishay; Ayer, Julian

2016-11-01

Anomalous origin of a branch pulmonary artery from the aorta is a rare malformation, accounting for 0.12% of all congenital heart defects. Anomalous origin of the left pulmonary artery from the aorta (ALPA) constitutes a small proportion of these cases. ALPA has been reported to arise from the ascending aorta with various embryologic postulates. We report a case of isolated ALPA arising from the descending aorta in association with a patent ductus arteriosus, to emphasize its embryologic ambiguity. Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Thrombus formation in the interrupted segment of the aorta.

PubMed

Karavelioğlu, Yusuf; Kalçık, Macit; Yetim, Mucahit; Doğan, Tolga; Gölbaşı, Zehra

2017-06-01

Interrupted aorta is a very rare heart defect in which there is a gap between the ascending and the descending thoracic aorta. It is usually associated with other cardiac anomalies, including ventricular septal defect, ductus arteriosus, and truncus arteriosus. Severe cases present with serious complications such as hypertension, heart failure, or intracranial hemorrhage. Neurological complications are very rare form of presentation and commonly associated with intracranial aneurysms. We have reported a case of interrupted aorta who presented with transient ischemic attack due to thrombus formation in the interrupted segment of the aorta. © 2017, Wiley Periodicals, Inc.

Penetrating injury of ascending aorta with arrow in situ.

PubMed

Lakhotia, Siddharth; Prakash, Shashi; Singh, Dinesh Kumar; Kumar, Ashok; Panigrahi, Debasish

2012-04-01

Penetrating injuries of the aorta are rare and highly lethal; very few patients are able to reach the hospital alive. We report a case of penetrating injury into the ascending aorta with the arrow still in situ, shot by a bow in a tribal region of India. The wound of entry into the aorta was sealed by the arrow itself. The patient came to us walking and supporting the arrow with his left hand. He was operated on, and the arrow was successfully removed from the aorta. Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Vasomotor function in rat arteries after ex vivo and intragastric exposure to food-grade titanium dioxide and vegetable carbon particles.

PubMed

Jensen, Ditte Marie; Christophersen, Daniel Vest; Sheykhzade, Majid; Skovsted, Gry Freja; Lykkesfeldt, Jens; Münter, Rasmus; Roursgaard, Martin; Loft, Steffen; Møller, Peter

2018-02-26

Humans are continuously exposed to particles in the gastrointestinal tract. Exposure may occur directly through ingestion of particles via food or indirectly by removal of inhaled material from the airways by the mucociliary clearance system. We examined the effects of food-grade particle exposure on vasomotor function and systemic oxidative stress in an ex vivo study and intragastrically exposed rats. In an ex vivo study, aorta rings from naïve Sprague-Dawley rats were exposed for 30 min to food-grade TiO 2 (E171), benchmark TiO 2 (Aeroxide P25), food-grade vegetable carbon (E153) or benchmark carbon black (Printex 90). Subsequently, the vasomotor function was assessed in wire myographs. In an in vivo study, lean Zucker rats were exposed intragastrically once a week for 10 weeks to vehicle, E171 or E153. Doses were comparable to human daily intake. Vasomotor function in the coronary arteries and aorta was assessed using wire myographs. Tetrahydrobiopterin, ascorbate, malondialdehyde and asymmetric dimethylarginine were measured in blood as markers of oxidative stress and vascular function. Direct exposure of E171 to aorta rings ex vivo increased the acetylcholine-induced vasorelaxation and 5-hydroxytryptamine-induced vasocontraction. E153 only increased acetylcholine-induced vasorelaxation, and Printex 90 increased the 5-hydroxytryptamine-induced vasocontraction, whereas Aeroxide P25 did not affect the vasomotor function. In vivo exposure showed similar results as ex vivo exposure; increased acetylcholine-induced vasorelaxation in coronary artery segments of E153 and E171 exposed rats, whereas E171 exposure altered 5-hydroxytryptamine-induced vasocontraction in distal coronary artery segments. Plasma levels of markers of oxidative stress and vascular function showed no differences between groups. Gastrointestinal tract exposure to E171 and E153 was associated with modest albeit statistically significant alterations in the vasocontraction and vasorelaxation responses. Direct particle exposure to aorta rings elicited a similar type of response. The vasomotor responses were not related to biomarkers of systemic oxidative stress.

Increased activity of vascular adenosine deaminase in atherosclerosis and therapeutic potential of its inhibition.

PubMed

Kutryb-Zajac, Barbara; Mateuszuk, Lukasz; Zukowska, Paulina; Jasztal, Agnieszka; Zabielska, Magdalena A; Toczek, Marta; Jablonska, Patrycja; Zakrzewska, Agnieszka; Sitek, Barbara; Rogowski, Jan; Lango, Romuald; Slominska, Ewa M; Chlopicki, Stefan; Smolenski, Ryszard T

2016-11-01

Extracellular nucleotides and adenosine that are formed or degraded by membrane-bound ecto-enzymes could affect atherosclerosis by regulating the inflammation and thrombosis. This study aimed to evaluate a relation between ecto-enzymes that convert extracellular adenosine triphosphate to adenine dinucleotide phosphate, adenosine monophosphate, adenosine, and inosine on the surface of the vessel wall with the severity or progression of experimental and clinical atherosclerosis. Furthermore, we tested whether the inhibition of adenosine deaminase will block the development of experimental atherosclerosis. Vascular activities of ecto-nucleoside triphosphate diphosphohydrolase 1, ecto-5'-nucleotidase, and ecto-adenosine deaminase (eADA) were measured in aortas of apolipoprotein E-/- low density lipoprotein receptor (ApoE-/-LDLR-/-) and wild-type mice as well as in human aortas. Plaques were analysed in the entire aorta, aortic root, and brachiocephalic artery by Oil-Red O and Orcein Martius Scarlet Blue staining and vascular accumulation of macrophages. The cellular location of ecto-enzymes was analysed by immunofluorescence. The effect of eADA inhibition on atherosclerosis progression was studied by a 2-month deoxycoformycin treatment of ApoE-/-LDLR-/- mice. The vascular eADA activity prominently increased in ApoE-/-LDLR-/- mice when compared with wild type already at the age of 1 month and progressed along atherosclerosis development, reaching a 10-fold difference at 10 months. The activity of eADA correlated with atherosclerotic changes in human aortas. High abundance of eADA in atherosclerotic vessels originated from activated endothelial cells and macrophages. There were no changes in ecto-nucleoside triphosphate diphosphohydrolase 1 activity, whereas ecto-5'-nucleotidase was moderately decreased in ApoE-/-LDLR-/- mice. Deoxycoformycin treatment attenuated plaque development in aortic root and brachiocephalic artery of ApoE-/-LDLR-/- mice, suppressed vascular inflammation and improved endothelial function. This study highlights the importance of extracellular nucleotides and adenosine metabolism in the atherosclerotic vessel in both experimental and clinical setting. The increased eADA activity marks an early stage of atherosclerosis, contributes to its progression and could represent a novel target for therapy. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For Permissions, please email: journals.permissions@oup.com.

Protective effect of soybeans as protein source in the diet against cadmium-aorta redox and morphological alteration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pérez Díaz, Matías F.F.; Acosta, Mariano; Mohamed, Fabián H.

We investigated the effects of cadmium exposition on thoracic aorta redox status and morphology, and the putative protective effect of soybeans in the diet. Male Wistar rats were separated into 6 groups: 3 fed with a diet containing casein and 3 containing soybeans, as protein source. Within each protein group, one was given tap water (control) and the other two tap water containing 15 and 100 ppm of Cd{sup 2+}, respectively, for two months. In rats fed with casein diet, 15 ppm of Cd induced an increase of thiobarbituric acid-reactive substances (TBARS), and of the catalase (CAT) and glutathione peroxidasemore » (GPx) activities, which were even higher with 100 ppm of Cd{sup 2+}, in aorta. Also, 100 ppm Cd{sup 2+} exposure increased superoxide dismutase (CuZnSOD) activity; CAT, GPX, SOD, Nrf2 and metallothioneine II mRNA expressions and CAT, GPx and NOX-2 protein levels, compared with control. Aorta endothelial and cytoplasmic alterations were observed. However, with the soybeans diet, 15 and 100 ppm of Cd{sup 2+} did not modify TBARS levels; CAT, GPX and Nrf2 mRNA expressions; CAT, GPx and NOX-2 protein; and the aorta morphology, compared with control. The soybean diet attenuates the redox changes and protects against morphological alterations induced, in a dose-dependent way, by Cd in aorta. - Highlights: • Under casein diet, 100 ppm Cd{sup 2+} in drinking water induces oxidative stress in aorta. • Under casein diet, 100 ppm Cd{sup 2+} increases Nrf2, MT II and NOX2 expressions in aorta. • Under casein diet, 100 ppm Cd{sup 2+} induces morphological changes in rat aorta. • The soybean diet attenuates the redox changes induced by Cd in rat aorta. • The soybean diet attenuates morphological alterations induced by Cd in rat aorta.« less

Automated quantitative 3D analysis of aorta size, morphology, and mural calcification distributions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurugol, Sila, E-mail: sila.kurugol@childrens.harvard.edu; Come, Carolyn E.; Diaz, Alejandro A.

Purpose: The purpose of this work is to develop a fully automated pipeline to compute aorta morphology and calcification measures in large cohorts of CT scans that can be used to investigate the potential of these measures as imaging biomarkers of cardiovascular disease. Methods: The first step of the automated pipeline is aorta segmentation. The algorithm the authors propose first detects an initial aorta boundary by exploiting cross-sectional circularity of aorta in axial slices and aortic arch in reformatted oblique slices. This boundary is then refined by a 3D level-set segmentation that evolves the boundary to the location of nearbymore » edges. The authors then detect the aortic calcifications with thresholding and filter out the false positive regions due to nearby high intensity structures based on their anatomical location. The authors extract the centerline and oblique cross sections of the segmented aortas and compute the aorta morphology and calcification measures of the first 2500 subjects from COPDGene study. These measures include volume and number of calcified plaques and measures of vessel morphology such as average cross-sectional area, tortuosity, and arch width. Results: The authors computed the agreement between the algorithm and expert segmentations on 45 CT scans and obtained a closest point mean error of 0.62 ± 0.09 mm and a Dice coefficient of 0.92 ± 0.01. The calcification detection algorithm resulted in an improved true positive detection rate of 0.96 compared to previous work. The measurements of aorta size agreed with the measurements reported in previous work. The initial results showed associations of aorta morphology with calcification and with aging. These results may indicate aorta stiffening and unwrapping with calcification and aging. Conclusions: The authors have developed an objective tool to assess aorta morphology and aortic calcium plaques on CT scans that may be used to provide information about the presence of cardiovascular disease and its clinical impact in smokers.« less

Automated quantitative 3D analysis of aorta size, morphology, and mural calcification distributions.

PubMed

Kurugol, Sila; Come, Carolyn E; Diaz, Alejandro A; Ross, James C; Kinney, Greg L; Black-Shinn, Jennifer L; Hokanson, John E; Budoff, Matthew J; Washko, George R; San Jose Estepar, Raul

2015-09-01

The purpose of this work is to develop a fully automated pipeline to compute aorta morphology and calcification measures in large cohorts of CT scans that can be used to investigate the potential of these measures as imaging biomarkers of cardiovascular disease. The first step of the automated pipeline is aorta segmentation. The algorithm the authors propose first detects an initial aorta boundary by exploiting cross-sectional circularity of aorta in axial slices and aortic arch in reformatted oblique slices. This boundary is then refined by a 3D level-set segmentation that evolves the boundary to the location of nearby edges. The authors then detect the aortic calcifications with thresholding and filter out the false positive regions due to nearby high intensity structures based on their anatomical location. The authors extract the centerline and oblique cross sections of the segmented aortas and compute the aorta morphology and calcification measures of the first 2500 subjects from COPDGene study. These measures include volume and number of calcified plaques and measures of vessel morphology such as average cross-sectional area, tortuosity, and arch width. The authors computed the agreement between the algorithm and expert segmentations on 45 CT scans and obtained a closest point mean error of 0.62 ± 0.09 mm and a Dice coefficient of 0.92 ± 0.01. The calcification detection algorithm resulted in an improved true positive detection rate of 0.96 compared to previous work. The measurements of aorta size agreed with the measurements reported in previous work. The initial results showed associations of aorta morphology with calcification and with aging. These results may indicate aorta stiffening and unwrapping with calcification and aging. The authors have developed an objective tool to assess aorta morphology and aortic calcium plaques on CT scans that may be used to provide information about the presence of cardiovascular disease and its clinical impact in smokers.

Automated quantitative 3D analysis of aorta size, morphology, and mural calcification distributions

PubMed Central

Kurugol, Sila; Come, Carolyn E.; Diaz, Alejandro A.; Ross, James C.; Kinney, Greg L.; Black-Shinn, Jennifer L.; Hokanson, John E.; Budoff, Matthew J.; Washko, George R.; San Jose Estepar, Raul

2015-01-01

Purpose: The purpose of this work is to develop a fully automated pipeline to compute aorta morphology and calcification measures in large cohorts of CT scans that can be used to investigate the potential of these measures as imaging biomarkers of cardiovascular disease. Methods: The first step of the automated pipeline is aorta segmentation. The algorithm the authors propose first detects an initial aorta boundary by exploiting cross-sectional circularity of aorta in axial slices and aortic arch in reformatted oblique slices. This boundary is then refined by a 3D level-set segmentation that evolves the boundary to the location of nearby edges. The authors then detect the aortic calcifications with thresholding and filter out the false positive regions due to nearby high intensity structures based on their anatomical location. The authors extract the centerline and oblique cross sections of the segmented aortas and compute the aorta morphology and calcification measures of the first 2500 subjects from COPDGene study. These measures include volume and number of calcified plaques and measures of vessel morphology such as average cross-sectional area, tortuosity, and arch width. Results: The authors computed the agreement between the algorithm and expert segmentations on 45 CT scans and obtained a closest point mean error of 0.62 ± 0.09 mm and a Dice coefficient of 0.92 ± 0.01. The calcification detection algorithm resulted in an improved true positive detection rate of 0.96 compared to previous work. The measurements of aorta size agreed with the measurements reported in previous work. The initial results showed associations of aorta morphology with calcification and with aging. These results may indicate aorta stiffening and unwrapping with calcification and aging. Conclusions: The authors have developed an objective tool to assess aorta morphology and aortic calcium plaques on CT scans that may be used to provide information about the presence of cardiovascular disease and its clinical impact in smokers. PMID:26328995

Aortic elongation and the risk for dissection: the Tübingen Aortic Pathoanatomy (TAIPAN) project†.

PubMed

Krüger, Tobias; Oikonomou, Alexandre; Schibilsky, David; Lescan, Mario; Bregel, Katharina; Vöhringer, Luise; Schneider, Wilke; Lausberg, Henning; Blumenstock, Gunnar; Bamberg, Fabian; Schlensak, Christian

2017-06-01

We measured aortic dimensions, particularly length parameters, using 3D imaging with the aim of refining the risk-morphology for Stanford type A aortic dissection (TAD). Computer tomography angiography studies were analysed using the curved multiplanar reformats. At defined landmarks, the diameters and lengths of aortic segments were recorded. Three groups were compared retrospectively: patients actually suffering from a TAD (TAD-group; n  = 150), patients before suffering a TAD (preTAD-group n  = 15) and a healthy control group ( n  = 215). Receiver operating characteristic curves (ROCs) were analysed (control versus preTAD) to study the diagnostic value of the individual variables. Median diameters of preTAD (43 mm) and TAD (50 mm) aortas were significantly ( P  < 0.001) larger than those of the control group (35 mm). Ninety-three percent of preTAD and 68% of TAD aortas were less than 55 mm in the mid-ascending aorta. The ascending aorta and the aortic arch were significantly longer in both preTAD and TAD aortas compared to control aortas ( P  < 0.001); in the control aortas the central line distance from the aortic valve to the brachiocephalic trunk was 93 mm. In preTAD aortas, it was 111 mm, and it was 117 mm in TAD aortas ( P  < 0.001). In ROC analysis, the area under the curve was 0.912 for the ascending diameter and 0.787 for the ascending and arch lengths. TAD-prediction based on the aortic diameter is ineffective. Besides circumferential dilatation, ascending aorta elongation precedes TAD and appears to be a useful additional parameter for prognostication. We propose a diagnostic score involving ascending aorta diameter and length. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Bicuspid aortic valve

MedlinePlus

... regulates blood flow from the heart into the aorta. The aorta is the major blood vessel that brings oxygen- ... blood to flow from the heart to the aorta. It prevents the blood from flowing back from ...

Cerebral and Renal Oxygen Saturation Are Not Compromised in the Presence of Retrograde Blood Flow in either the Ascending or Descending Aorta in Term or Near-Term Infants with Left-Sided Obstructive Lesions.

PubMed

van der Laan, Michelle E; Mebius, Mirthe J; Roofthooft, Marcus T R; Bos, Arend F; Berger, Rolf M F; Kooi, Elisabeth M W

2017-01-01

In infants with left-sided obstructive lesions (LSOL), the presence of retrograde blood flow in either the ascending or descending aorta may lead to diminished cerebral and renal blood flow, respectively. Our aim was to compare cerebral and renal tissue oxygen saturation (rSO2) between infants with LSOL with antegrade and retrograde blood flow in the ascending aorta and with and without diastolic backflow in the descending aorta. Based on 2 echocardiograms, the study group was categorized according to the direction of blood flow in the ascending and descending aorta. We measured cerebral and renal rSO2 using near-infrared spectroscopy and calculated fractional tissue oxygen extraction (FTOE). Nineteen infants with LSOL, admitted to the NICU between 0 and 28 days after birth, were included. Infants with antegrade blood flow (n = 12) and infants with retrograde blood flow in the ascending aorta (n = 7) had similar cerebral rSO2 and FTOE during both echocardiograms. Only during the first echocardiogram, infants with retrograde blood flow in the ascending aorta had lower renal FTOE (0.14 vs. 0.32, p = 0.04) and tended to have higher renal rSO2 (80 vs. 65%, p = 0.09). The presence of diastolic backflow in the descending aorta was not associated with cerebral or renal rSO2 and FTOE during the first (n = 8) as well as the second echocardiogram (n = 10). Retrograde blood flow in the ascending aorta was not associated with cerebral oxygenation, while diastolic backflow in the descending aorta was not associated with renal oxygenation in infants with LSOL. © 2017 S. Karger AG, Basel.

Neuropilin 1 expression in human aortas, coronaries and the main bypass grafts.

PubMed

Alattar, Mohamed; Jiang, Chunyang; Luan, Zhou; Pan, Tiecheng; Liu, Ligang; Li, Jun

2014-12-01

Development of intimal hyperplasia (IH) is the main pathology underlying graft failure following coronary artery bypass graft surgeries for ischaemic heart diseases, especially for great saphenous vein grafts which have a lower patency rate than internal mammary arteries. Neuropilin 1 (NRP1), which is a co-receptor for vascular endothelial growth factor found in vascular endothelial and smooth muscle cells, affects the development of IH. We examined the difference in NRP1 expression and distribution in human coronaries, aortas, mammary arteries and saphenous veins to detect a possible relation to their susceptibility to IH. Ninety-five human vascular segments obtained from 40 patients were used for the comparison of NRP1 expression between different groups of blood vessels by western blot and real-time PCR. Additionally, staining scores were generated by computerized analysis of the microscopic images obtained after immunofluorescence and immunohistochemical staining to compare NRP1 expression patterns in endothelium, smooth muscles and adventitia in each vessel type. NRP1 expression in the aorta (2.03 ± 1.44) was more than twice as high as mammary artery expression (0.85 ± 0.75; n = 16, P = 0.0004); NRP1 of the latter (0.99 ± 0.91) was more than 30% greater than that of the corresponding saphenous vein (0.73 ± 0.69; n = 20, P = 0.0085). In adventitia, NRP1 receptor staining of the saphenous vein was higher (22.96 ± 8.73) than in the mammary artery (15.83 ± 7.13; n = 7, P = 0.049). Variations in NRP1 protein levels were accompanied by parallel variations in its mRNA levels (n = 15, P = 0.34). Autologous saphenous vein grafts, unlike internal mammary artery grafts, have lower NRP1 expression and abundant adventitial distribution of NRP1 within their walls; this may correlate with higher susceptibility to IH development. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Using In Vivo and Tissue and Cell Explant Approaches to Study the Morphogenesis and Pathogenesis of the Embryonic and Perinatal Aorta.

PubMed

Misra, Ashish; Feng, Zhonghui; Zhang, Jiasheng; Lou, Zhi-Yin; Greif, Daniel M

2017-09-12

The aorta is the largest artery in the body. The aortic wall is composed of an inner layer of endothelial cells, a middle layer of alternating elastic lamellae and smooth muscle cells (SMCs), and an outer layer of fibroblasts and extracellular matrix. In contrast to the widespread study of pathological models (e.g., atherosclerosis) in the adult aorta, much less is known about the embryonic and perinatal aorta. Here, we focus on SMCs and provide protocols for the analysis of the morphogenesis and pathogenesis of embryonic and perinatal aortic SMCs in normal development and disease. Specifically, the four protocols included are: i) in vivo embryonic fate mapping and clonal analysis; ii) explant embryonic aorta culture; iii) SMC isolation from the perinatal aorta; and iv) subcutaneous osmotic mini-pump placement in pregnant (or non-pregnant) mice. Thus, these approaches facilitate the investigation of the origin(s), fate, and clonal architecture of SMCs in the aorta in vivo. They allow for modulating embryonic aorta morphogenesis in utero by continuous exposure to pharmacological agents. In addition, isolated aortic tissue explants or aortic SMCs can be used to gain insights into the role of specific gene targets during fundamental processes such as muscularization, proliferation, and migration. These hypothesis-generating experiments on isolated SMCs and the explanted aorta can then be assessed in the in vivo context through pharmacological and genetic approaches.

A Circular Surgical Stapler Designed to Anastomose Aorta and Dacron Tube Graft

PubMed Central

2013-01-01

Background: A circular aortic stapler has been developed to anastomose the open end of the aorta to a size-matched Dacron tube graft in one quick motion and without having to pull sutures through the aortic wall. Methods: A prototype was developed, and its design and function were tested in bench experiments and compared with hand-sewn anastomosis. The basic design of the stapler is a central rod (anvil) surrounded by 10 stapling limbs, which can be closed over the anvil in a full circle, with staples extruded by turning a knob at the back. To test its function, a Dacron tube graft was inserted in the middle of a length of bovine aorta. One side was anastomosed with the stapler and the other hand-sewn in each of 10 experiments. Bovine blood was infused under increasing pressure. Results: It took considerably less time to complete the stapled anastomosis than the hand-sewn side (3 minutes, 46 seconds versus 15 minutes, 42 seconds). Initial leak occurred at low pressures on the hand-sewn side (mean pressure 40 mm Hg) compared with the stapled side (mean pressure 70 mm Hg). In 7 of 10 experiments, the leak became too brisk on the hand-sewn side to sustain pressure, compared with 3 of 10 with stapled anastomoses. The stapling device performed well in all cases except when the bovine aorta was too thick for the staples (two cases) or when there was a missed branch at the anastomotic site (one case). Conclusions: These experiments validate the concept and the design of this aortic stapler. There are some limitations in the current design, which will need to be modified before its use in live animals or clinically. PMID:26798678

A Circular Surgical Stapler Designed to Anastomose Aorta and Dacron Tube Graft: Validation of the Concept and Comparison to Hand-Sewn Anastomosis in Bench Experiments.

PubMed

Raza, Syed T

2013-06-01

A circular aortic stapler has been developed to anastomose the open end of the aorta to a size-matched Dacron tube graft in one quick motion and without having to pull sutures through the aortic wall. A prototype was developed, and its design and function were tested in bench experiments and compared with hand-sewn anastomosis. The basic design of the stapler is a central rod (anvil) surrounded by 10 stapling limbs, which can be closed over the anvil in a full circle, with staples extruded by turning a knob at the back. To test its function, a Dacron tube graft was inserted in the middle of a length of bovine aorta. One side was anastomosed with the stapler and the other hand-sewn in each of 10 experiments. Bovine blood was infused under increasing pressure. It took considerably less time to complete the stapled anastomosis than the hand-sewn side (3 minutes, 46 seconds versus 15 minutes, 42 seconds). Initial leak occurred at low pressures on the hand-sewn side (mean pressure 40 mm Hg) compared with the stapled side (mean pressure 70 mm Hg). In 7 of 10 experiments, the leak became too brisk on the hand-sewn side to sustain pressure, compared with 3 of 10 with stapled anastomoses. The stapling device performed well in all cases except when the bovine aorta was too thick for the staples (two cases) or when there was a missed branch at the anastomotic site (one case). These experiments validate the concept and the design of this aortic stapler. There are some limitations in the current design, which will need to be modified before its use in live animals or clinically.

Heterogeneity in the Segmental Development of the Aortic Tree: Impact on Management of Genetically Triggered Aortic Aneurysms

PubMed Central

Sherif, Hisham M.F.

2014-01-01

An extensive search of the medical literature examining the development of the thoracic aortic tree reveals that the thoracic aorta does not develop as one unit or in one stage: the oldest part of the thoracic aorta is the descending aorta with the aortic arch being the second oldest, developing under influence from the neural crest cell. Following in chronological order are the proximal ascending aorta and aortic root, which develop from a conotruncal origin. Different areas of the thoracic aorta develop under the influence of different gene sets. These parts develop from different cell lineages: the aortic root (the conotruncus), developing from the mesoderm; the ascending aorta and aortic arch, developing from the neural crest cells; and the descending aorta from the mesoderm. Findings illustrate that the thoracic aorta is not a single entity, in developmental terms. It develops from three or four distinct areas, at different stages of embryonic life, and under different sets of genes and signaling pathways. Genetically triggered thoracic aortic aneurysms are not a monolithic group but rather share a multi-genetic origin. Identification of therapeutic targets should be based on the predilection of certain genes to cause aneurysmal disease in specific aortic segments. PMID:26798739

Hypolipidemic and anti-inflammatory effects of aorta and heart tissues of cattle and pigs in the atherosclerosis rat model.

PubMed

Chernukha, Irina M; Fedulova, Liliya V; Kotenkova, Elena A; Takeda, Shiro; Sakata, Ryoichi

2018-05-01

The aim of this study was to investigate the effects of aorta and heart tissues obtained from cattle and pigs on atherosclerosis disorders. Atherosclerosis model rats were provided with the respective diets consisting of aorta and heart tissues. Administration of each tissue suppressed body weight gain as compared to that of the control. In particular, the aorta tissues of pigs and cattle demonstrated significant suppressions in body weight gain in the model rats. The aorta tissues of pigs and cattle showed a significant increase and decrease in the serum high-density lipoproteins and atherogenic index, respectively, which was correlated with the increase in apolipoprotein A1. Hematological analysis revealed that aorta tissues of pigs and cattle clearly reduced the ratio of granulocytes/lymphocytes in the atherosclerosis rats. Serum vascular cellular adhesion molecule-1 levels in the atherosclerosis rats, which were administered these aorta tissues, were also significantly reduced. Additionally, there was an increase in von Willebrand factor in the rat serum. Based on the results obtained, the aorta tissues of pigs and cattle, in particular, demonstrated positive effects in the atherosclerosis rats due to the alteration of lipid metabolism and reduction in inflammation related to atherosclerosis. © 2018 Japanese Society of Animal Science.

Assessment of Hemodynamic Conditions in the Aorta Following Root Replacement with Composite Valve-Conduit Graft.

PubMed

Cheng, Zhuo; Kidher, Emaddin; Jarral, Omar A; O'Regan, Declan P; Wood, Nigel B; Athanasiou, Thanos; Xu, Xiao Yun

2016-05-01

This paper presents the analysis of detailed hemodynamics in the aortas of four patients following replacement with a composite bio-prosthetic valve-conduit. Magnetic resonance image-based computational models were set up for each patient with boundary conditions comprising subject-specific three-dimensional inflow velocity profiles at the aortic root and central pressure waveform at the model outlet. Two normal subjects were also included for comparison. The purpose of the study was to investigate the effects of the valve-conduit on flow in the proximal and distal aorta. The results suggested that following the composite valve-conduit implantation, the vortical flow structure and hemodynamic parameters in the aorta were altered, with slightly reduced helical flow index, elevated wall shear stress and higher non-uniformity in wall shear compared to normal aortas. Inter-individual analysis revealed different hemodynamic conditions among the patients depending on the conduit configuration in the ascending aorta, which is a key factor in determining post-operative aortic flow. Introducing a natural curvature in the conduit to create a smooth transition between the conduit and native aorta may help prevent the occurrence of retrograde and recirculating flow in the aortic arch, which is particularly important when a large portion or the entire ascending aorta needs to be replaced.

[Graft Pseudoaneurysm after Ascending to Abdominal Aorta Bypass for Atypical Coarctation Due to Aortitis Syndrome;Report of a Case].

PubMed

Yada, Masashi; Yamanaka, Kazuo; Miwa, Senri; Hirose, Keiichi; Sakaguchi, Hisashi; Yoshida, Yukiyo; Onga, Youhei; Tara, Yuichi

2017-05-01

We present a case of a 44-year-old woman, with pseudoaneurysm formation at the middle of the prosthetic graft, 60 mm in diameter. She had been diagnosed with atypical coarctation due to aortitis 27 years before, and had undergone a bypass operation with 14 mm-diameter Cooley double velour graft from the ascending aorta to the abdominal aorta. This time, endovascular aortic repair was performed to prevent rupture of the pseudoaneurysm. Though a knitted Dacron graft has a risk of psuedaneurysm formation long patency could be obtained when used in ascending aorta-abdominal aorta bypass.

Severe Obstructive Calcification of the Descending Aorta: A Case Report of "Coral Reef Aorta".

PubMed

Ishigaki, Takahiro; Matsuda, Hitoshi; Henmi, Soichiro; Yoshida, Masato; Mukohara, Nobuhiko

2017-06-25

An 82-year-old man suffering from lower back pain and dyspnea presented to our institute in a state of shock. Computed tomography showed subtotal occlusion of the descending aorta with massive atherosclerotic calcification. As the proximal portion of the superior mesenteric artery was obstructed, emergency bypass from the right axillary artery to the bilateral external iliac arteries was performed, but the patient died 2 days later. Autopsy revealed that reddish-brown and verrucous masses obstructed the descending aorta, and high-grade thickening of the intima and extensive deposits of calcium in the lumina and medial layer were detected in the descending aorta histologically.

Genetics Home Reference: familial thoracic aortic aneurysm and dissection

MedlinePlus

... and dissection ( familial TAAD ) involves problems with the aorta , which is the large blood vessel that distributes ... Familial TAAD affects the upper part of the aorta, near the heart. This part of the aorta ...

Primitive macrophages control HSPC mobilization and definitive haematopoiesis.

PubMed

Travnickova, Jana; Tran Chau, Vanessa; Julien, Emmanuelle; Mateos-Langerak, Julio; Gonzalez, Catherine; Lelièvre, Etienne; Lutfalla, Georges; Tavian, Manuela; Kissa, Karima

2015-02-17

In vertebrates, haematopoietic stem/progenitor cells (HSPCs) first emerge in the aorta-gonad-mesonephros (AGM) before colonizing transitory and subsequently definitive haematopoietic organs allowing haematopoiesis throughout adult life. Here we identify an unexpected primitive macrophage population accumulated in the dorsal mesenteric mesoderm surrounding the dorsal aorta of the human embryo and study its function in the transparent zebrafish embryo. Our study reveals dynamic interactions occurring between the HSPCs and primitive macrophages in the AGM. Specific chemical and inducible genetic depletion of macrophages or inhibition of matrix metalloproteinases (Mmps) leads to an accumulation of HSPCs in the AGM and a decrease in the colonization of haematopoietic organs. Finally, in vivo zymography demonstrates the function of primitive macrophages in extracellular matrix degradation, which allows HSPC migration through the AGM stroma, their intravasation, leading to the colonization of haematopoietic organs and the establishment of definitive haematopoiesis.

What Is a Stent?

MedlinePlus

... the artery and keep it open. For the Aorta in the Abdomen or Chest The aorta is a major artery that carries oxygen-rich ... the abdomen. Over time, some areas of the aorta's walls can weaken. These weak areas can cause ...

A rare case of acyanotic congenital heart disease, large patent ductus arteriosus with pre-ductal coarctation of descending thoracic aorta with patent ductus arteriosus closure and extra anatomical bypass grafting.

PubMed

Wani, Zara; Tiwari, Deepak; Gehlot, Rajeev; Kumar, Deepak; Chhabra, Sushil; Sharma, Meenaxi

2017-01-01

We report a case of 18-year-old female patient with large patent ductus arteriosus (PDA)-preductal coarctation of descending thoracic aorta. She underwent large PDA closure with a prosthetic graft from ascending aorta to descending thoracic aorta by mid-sternotomy on cardiopulmonary bypass machine under total hypothermic circulatory arrest.

[Application of a tape-like bandage for the ascending aorta in its poststenotic dilation and correction of the aortal valve stenosis].

PubMed

Popov, V V; Bol'shak, A A

2014-06-01

The aortal valve prosthesis in combination with a tape-like bandage of ascending aorta application was performed in 106 patients, suffering a failure with predominance of the aortal valve stenosis in conjunction with the ascending aorta poststenotic dilation, in a 2005 - 2014 yrs period in the clinic. The hospital lethality have constituted 0.9%. In accordance to echocardiography, the ascending aorta diameter preoperatively have constituted (48.7 +/- 1.4) mm at average, before discharge from the hospital--(40.1 +/- 1.2) mm, in late follow-up period--(41.3 +/- 1.2) mm. It is expedient to recommend the original method of a tape-like bandage of ascending aorta from the base of noncoronary sinus in the aortal sinuses dilation (45 mm and more) in combination with the aortal valve prosthesis in poststenotic dilation of ascending aorta.

Metoprolol Reduces Proinflammatory Cytokines and Atherosclerosis in ApoE−/− Mice

PubMed Central

Ulleryd, Marcus A.; Bernberg, Evelina; Yang, Li Jin; Bergström, Göran M. L.; Johansson, Maria E.

2014-01-01

A few studies in animals and humans suggest that metoprolol (β1-selective adrenoceptor antagonist) may have a direct antiatherosclerotic effect. However, the mechanism behind this protective effect has not been established. The aim of the present study was to evaluate the effect of metoprolol on development of atherosclerosis in ApoE−/− mice and investigate its effect on the release of proinflammatory cytokines. Male ApoE−/− mice were treated with metoprolol (2.5 mg/kg/h) or saline for 11 weeks via osmotic minipumps. Atherosclerosis was assessed in thoracic aorta and aortic root. Total cholesterol levels and Th1/Th2 cytokines were analyzed in serum and macrophage content in lesions by immunohistochemistry. Metoprolol significantly reduced atherosclerotic plaque area in thoracic aorta (P < 0.05 versus Control). Further, metoprolol reduced serum TNFα and the chemokine CXCL1 (P < 0.01 versus Control for both) as well as decreasing the macrophage content in the plaques (P < 0.01 versus Control). Total cholesterol levels were not affected. In this study we found that a moderate dose of metoprolol significantly reduced atherosclerotic plaque area in thoracic aorta of ApoE−/− mice. Metoprolol also decreased serum levels of proinflammatory cytokines TNFα and CXCL1 and macrophage content in the plaques, showing that metoprolol has an anti-inflammatory effect. PMID:25105129

Impaired Collagen Biosynthesis and Cross‐linking in Aorta of Patients With Bicuspid Aortic Valve

PubMed Central

Wågsäter, Dick; Paloschi, Valentina; Hanemaaijer, Roeland; Hultenby, Kjell; Bank, Ruud A.; Franco‐Cereceda, Anders; Lindeman, Jan H. N.; Eriksson, Per

2013-01-01

Background Patients with bicuspid aortic valve (BAV) have an increased risk of developing ascending aortic aneurysm. In the present study, collagen homeostasis in nondilated and dilated aorta segments from patients with BAV was studied, with normal and dilated aortas from tricuspid aortic valve (TAV) patients as reference. Methods and Results Ascending aortas from 56 patients were used for biochemical and morphological analyses of collagen. mRNA expression was analyzed in 109 patients. Collagen turnover rates were similar in nondilated and dilated aortas of BAV patients, showing that aneurysmal formation in BAV is, in contrast to TAV, not associated with an increased collagen turnover. However, BAV in general was associated with an increased aortic collagen turnover compared with nondilated aortas of TAV patients. Importantly, the ratio of hydroxylysyl pyridinoline (HP) to lysyl pyridinoline (LP), 2 distinct forms of collagen cross‐linking, was lower in dilated aortas from patients with BAV, which suggests that BAV is associated with a defect in the posttranslational collagen modification. This suggests a deficiency at the level of lysyl hydroxylase (PLOD1), which was confirmed by mRNA and protein analyses that showed reduced PLOD1 expression but normal lysyl oxidase expression in dilated aortas from patients with BAV. This suggests that impaired collagen cross‐linking in BAV patients may be attributed to changes in the expression and/or activity of PLOD1. Conclusions Our results demonstrate an impaired biosynthesis and posttranslational modification of collagen in aortas of patients with BAV, which may explain the increased aortic aneurysm formation in BAV patients. PMID:23525417

Aortic valve surgery - open

MedlinePlus

... and into a large blood vessel called the aorta. The aortic valve separates the heart and aorta. The aortic valve opens so blood can flow ... to be able to see your heart and aorta. You may need to be connected to a ...

Sulforaphane reduces advanced glycation end products (AGEs)-induced inflammation in endothelial cells and rat aorta.

PubMed

Matsui, T; Nakamura, N; Ojima, A; Nishino, Y; Yamagishi, S-I

2016-09-01

Advanced glycation end products (AGEs)-receptor RAGE interaction evokes oxidative stress and inflammatory reactions, thereby being involved in endothelial cell (EC) damage in diabetes. Sulforaphane is generated from glucoraphanin, a naturally occurring isothiocyanate found in widely consumed cruciferous vegetables, by myrosinase. Sulforaphane has been reported to protect against oxidative stress-mediated cell and tissue injury. However, effects of sulforaphane on AGEs-induced vascular damage remain unclear. In this study, we investigated whether and how sulforaphane could inhibit inflammation in AGEs-exposed human umbilical vein ECs (HUVECs) and AGEs-injected rat aorta. Sulforaphane treatment for 4 or 24 h dose-dependently inhibited the AGEs-induced increase in RAGE, monocyte chemoattractant protein-1 (MCP-1), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecular-1 (VCAM-1) gene expression in HUVECs. AGEs significantly stimulated MCP-1 production by, and THP-1 cell adhesion to, HUVECs, both of which were prevented by 1.6 μM sulforaphane. Sulforaphane significantly suppressed oxidative stress generation and NADPH oxidase activation evoked by AGEs in HUVECs. Furthermore, aortic RAGE, ICAM-1 and VCAM-1 expression in AGEs-injected rats were increased, which were suppressed by simultaneous infusion of sulforaphane. The present study demonstrated for the first time that sulforaphane could inhibit inflammation in AGEs-exposed HUVECs and AGEs-infused rat aorta partly by suppressing RAGE expression through its anti-oxidative properties. Inhibition of the AGEs-RAGE axis by sulforaphane might be a novel therapeutic target for vascular injury in diabetes. Copyright © 2016 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

Irisin protects against endothelial injury and ameliorates atherosclerosis in apolipoprotein E-Null diabetic mice.

PubMed

Lu, Junyan; Xiang, Guangda; Liu, Min; Mei, Wen; Xiang, Lin; Dong, Jing

2015-12-01

The circulating irisin increases energy expenditure and improves insulin resistance in mice and humans. The improvement of insulin resistance ameliorates atherosclerosis. Therefore, we hypothesized that irisin alleviates atherosclerosis in diabetes. Endothelial function was measured by acetylcholine-induced endothelium-dependent vasodilation using aortic rings in apolipoprotein E-Null (apoE(-/-)) streptozotocin-induced diabetic mice. Atherosclerotic lesion was evaluated by plaque area and inflammatory response in aortas. In addition, the endothelium-protective effects of irisin were also further investigated in primary human umbilical vein endothelial cells (HUVECs) in vitro. The in vivo experiments showed that irisin treatment significantly improved endothelial dysfunction, decreased endothelial apoptosis, and predominantly decreased atherosclerotic plaque area of both en face and cross sections when compared with normal saline-treated diabetic mice. Moreover, the infiltrating macrophages and T lymphocytes within plaque and the mRNA expression levels of inflammatory cytokines in aortas were also significantly reduced by irisin treatment in mice. The in vitro experiments revealed that irisin inhibited high glucose-induced apoptosis, oxidative stress and increased antioxidant enzymes expression in HUVECs, and pretreatment with LY294002, l-NAME, AMPK-siRNA or eNOS-siRNA, attenuated the protection of irisin on HUVECs apoptosis induced by high glucose. In addition, the in vivo and in vitro experiments showed that irisin increased the phosphorylation of AMPK, Akt and eNOS in aortas and cultured HUVECs. The present study indicates that systemic administration of irisin may be protected against endothelial injury and ameliorated atherosclerosis in apoE(-/-) diabetic mice. The endothelium-protective action of irisin was through activation of AMPK-PI3K-Akt-eNOS signaling pathway. Irisin could be therapeutic for atherosclerotic vascular diseases in diabetes. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Postnatal Deletion of the Type II Transforming Growth Factor-β Receptor in Smooth Muscle Cells Causes Severe Aortopathy in Mice.

PubMed

Hu, Jie Hong; Wei, Hao; Jaffe, Mia; Airhart, Nathan; Du, Liang; Angelov, Stoyan N; Yan, James; Allen, Julie K; Kang, Inkyung; Wight, Thomas N; Fox, Kate; Smith, Alexandra; Enstrom, Rachel; Dichek, David A

2015-12-01

Prenatal deletion of the type II transforming growth factor-β (TGF-β) receptor (TBRII) prevents normal vascular morphogenesis and smooth muscle cell (SMC) differentiation, causing embryonic death. The role of TBRII in adult SMC is less well studied. Clarification of this role has important clinical implications because TBRII deletion should ablate TGF-β signaling, and blockade of TGF-β signaling is envisioned as a treatment for human aortopathies. We hypothesized that postnatal loss of SMC TBRII would cause aortopathy. We generated mice with either of 2 tamoxifen-inducible SMC-specific Cre (SMC-CreER(T2)) alleles and homozygous floxed Tgfbr2 alleles. Mice were injected with tamoxifen, and their aortas examined 4 and 14 weeks later. Both SMC-CreER(T2) alleles efficiently and specifically rearranged a floxed reporter gene and efficiently rearranged a floxed Tgfbr2 allele, resulting in loss of aortic medial TBRII protein. Loss of SMC TBRII caused severe aortopathy, including hemorrhage, ulceration, dissection, dilation, accumulation of macrophage markers, elastolysis, abnormal proteoglycan accumulation, and aberrant SMC gene expression. All areas of the aorta were affected, with the most severe pathology in the ascending aorta. Cre-mediated loss of SMC TBRII in vitro ablated both canonical and noncanonical TGF-β signaling and reproduced some of the gene expression abnormalities detected in vivo. SMC TBRII plays a critical role in maintaining postnatal aortic homeostasis. Loss of SMC TBRII disrupts TGF-β signaling, acutely alters SMC gene expression, and rapidly results in severe and durable aortopathy. These results suggest that pharmacological blockade of TGF-β signaling in humans could cause aortic disease rather than prevent it. © 2015 American Heart Association, Inc.

Anti-atherosclerotic effects of pravastatin in brachiocephalic artery in comparison with en face aorta and aortic roots in ApoE/LDLR-/- mice.

PubMed

Kostogrys, Renata B; Franczyk-Zarow, Magdalena; Gasior-Glogowska, Marlena; Kus, Edyta; Jasztal, Agnieszka; Wrobel, Tomasz P; Baranska, Malgorzata; Czyzynska-Cichon, Izabela; Drahun, Anna; Manterys, Angelika; Chlopicki, Stefan

2017-02-01

Cholesterol-dependent and independent mechanisms were proposed to explain anti-atherosclerotic action of statins in humans. However, their effects in murine models of atherosclerosis have not been consistently demonstrated. Here, we studied the effects of pravastatin on atherosclerosis in ApoE/LDLR -/- mice fed a control and atherogenic diet. ApoE/LDLR -/- mice were fed a control (CHOW) or an atherogenic (Low Carbohydrate High Protein, LCHP) diet. Two doses of pravastatin (40mg/kg and 100mg/kg) were used. The anti-atherosclerotic effects of pravastatin in en face aorta, cross-sections of aortic roots and brachiocephalic artery (BCA) were analysed. The lipid profile was determined. Fourier Transform Infrared Spectroscopy followed by Fuzzy C-Means (FCM) clustering was used for the quantitative assessment of plaque composition. Treatment with pravastatin (100mg/kg) decreased total and LDL cholesterol only in the LCHP group, but displayed a pronounced anti-atherosclerotic effect in BCA and abdominal aorta. The anti-atherosclerotic effect of pravastatin (100mg/kg) in BCA was associated with significant alterations of the chemical plaque composition, including a fall in cholesterol and cholesterol esters contents independently on total cholesterol and LDL concentration in plasma. Pravastatin at high (100mg/kg), but not low dose displayed a pronounced anti-atherosclerotic effect in ApoE/LDLR -/- mice fed a CHOW or LCHP diet that was remarkable in BCA, visible in en face aorta, whereas it was not observed in aortic roots, suggesting that previous inconsistencies might have been due to the various sites of atherosclerotic plaque analysis. Copyright © 2016. Published by Elsevier Urban & Partner Sp. z o.o.

Modelling atherosclerosis by proteomics: Molecular changes in the ascending aortas of cholesterol-fed rabbits.

PubMed

Xu, Jingshu; Jüllig, Mia; Middleditch, Martin J; Cooper, Garth J S

2015-09-01

The cholesterol-fed rabbit is commonly used as a model to study the vascular effects of hypercholesterolemia and resulting atherosclerotic lesions. Here we undertook a proteomic case-control investigation of ascending aortas from male New Zealand White rabbits after 10 weeks on a high-cholesterol (2% w/w) diet (HCD, n = 5) or control diet (n = 5), in order to determine the changes in response to the HCD. Histology confirmed intimal thickening in the HCD group consistent with atherosclerosis, and LC-MS/MS analysis of individually-obtained ascending aortic extracts labelled with isobaric (iTRAQ) tags enabled the identification and quantitation of 453 unique proteins above the 1% false discovery rate threshold. Of 67 proteins showing significant differences in relative abundance (p < 0.05), 62 were elevated and five decreased in ascending aortas from HCD-fed rabbits compared to controls. Six proteins were selected for validation using Multiple Reaction Monitoring, which confirmed the iTRAQ results. Many of the observed protein changes are consistent with known molecular perturbations in the ascending aorta that occur in response to hypercholesterolemia, e.g. elevation of tissue levels of apolipoproteins, extracellular matrix adhesion proteins, glycolytic enzymes, heat shock proteins and proteins involved in immune defense. We also made a number of novel observations, including a 15-fold elevation of glycoprotein (trans-membrane) nmb-like (Gpnmb) in response to HCD. Gpnmb has previously been linked to angiogenesis but not to atherosclerosis. This and additional novel observations merit further investigation as these perturbations may play important and as yet undiscovered roles in the pathogenesis of atherosclerosis in rabbits as well as humans. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

In-vivo characterization of a 3D hybrid scaffold based on PCL/decellularized aorta for tracheal tissue engineering.

PubMed

Ghorbani, Fariba; Moradi, Lida; Shadmehr, Mohammad Behgam; Bonakdar, Shahin; Droodinia, Atosa; Safshekan, Farzaneh

2017-12-01

As common treatments for long tracheal stenosis are associated with several limitations, tracheal tissue engineering is considered as an alternative treatment. This study aimed at preparing a hybrid scaffold, based on biologic and synthetic materials for tracheal tissue engineering. Three electrospun polycaprolactone (PCL) scaffolds, namely E1 (pure PCL), E2 (collagen-coated PCL) and E3 (PCL blended with collagen) were prepared. Allogeneic aorta was harvested and decellularized. A biodegradable PCL stent was fabricated and inserted into the aorta to prevent its collapse. Scaffold characterization results revealed that the 2-h swelling ratio of E2 was significantly higher than those of E1 and E3. In the first 3months, E2 and E3 exhibited almost equal degradabilities (significantly higher than that of E1). Moreover, tensile strengths of all samples were comparable with those of human trachea. Using rabbit's adipose-derived mesenchymal stem cells (AMSCs) and primary chondrocytes, E3 exhibited the highest levels of GAG release within 21days as well as collagen II and aggrecan expression. Fot the next step, AMSC-chondrocyte co-culture seeded scaffold was sutured to the acellular aorta, implanted into rabbits' muscle, and finally harvested after 4weeks of follow up. Harvested structures were totally viable due to the angiogenesis created by the muscle. H&E and alcian blue staining results revealed the presence of chondrocytes in the structure and GAG in the produced extracellular matrix. Since tracheal replacement using biologic and synthetic scaffolds usually results in tracheal collapse or granulation formation, a hybrid construct may provide the required rigidity and biocompatibility for the substitute. Copyright © 2017. Published by Elsevier B.V.

Dacron graft as replacement to dissected aorta: A three-dimensional fluid-structure-interaction analysis.

PubMed

Jayendiran, R; Nour, B M; Ruimi, A

2018-02-01

Aortic dissection (AD) is a serious medical condition characterized by a tear in the intima, the inner layer of the aortic walls. In such occurrence, blood is being diverted to the media (middle) layer and may result in patient death if not quickly attended. In the case where the diseased portion of the aorta needs to be replaced, one common surgical technique is to use a graft made of Dacron, a synthetic fabric. We investigate the response of a composite human aortic segment-Dacron graft structure subjected to blood flow using the three-dimensional fluid-structure-interaction (FSI) capability in Abaqus. We obtain stress and strain profiles in each of the three layers of the aortic walls as well as in the Dacron graft. Results are compared when elastic and hyperelastic models are used and when isotropy vs. anisotropy is assumed. The more complex case (hyperelastic-anisotropy) is represented by the Holzapfel-Gasser-Ogden (HGO) model which also accounts for the orientation of the fibers present in the tissues. The fluid flow is taken as Newtonian, incompressible, pulsatile and turbulent. The simulation show that for all the cases, the von Mises stress distribution at aorta-Dacron interface is well below the ultimate strength of the aorta. No significant change in radial displacement at the interface of the two materials due to blood flow is observed. Computation cost is also addressed and results show that the hyperelastic-anisotropic model takes about three times longer to run than the elastic isotropic case. Trade-off between accuracy and computational cost has to be weighted. Copyright © 2017 Elsevier Ltd. All rights reserved.

Endovascular Treatment of Distal Aortic Arch Aneurysm Associated with Coarctation of Aorta in a Jehovah's Witness

PubMed Central

Mannacio, Vito A.; Di Tommaso, Ettorino; Pinna, Giovanni B.; Fontana, Immacolata; Iannelli, Gabriele

2017-01-01

Late aneurysm formation in the proximal aorta or distal aortic arch is a recognized sequela of untreated stenosis of the aortic isthmus and is associated with substantial risk of aortic rupture. We describe the case of a 44-year-old man with untreated coarctation of the aorta who presented with a prestenotic dissecting thoracic aortic aneurysm. He declined surgery because he was a Jehovah's Witness. Instead, we performed emergency endovascular aortic repair in which 2 stent-grafts were placed in the descending aorta. Our experience suggests that this procedure is a useful and safe alternative to open surgery in patients who have aneurysms associated with coarctation of the aorta. PMID:29276439

Monte Carlo simulation of aorta autofluorescence

NASA Astrophysics Data System (ADS)

Kuznetsova, A. A.; Pushkareva, A. E.

2016-08-01

Results of numerical simulation of autofluorescence of the aorta by the method of Monte Carlo are reported. Two states of the aorta, normal and with atherosclerotic lesions, are studied. A model of the studied tissue is developed on the basis of information about optical, morphological, and physico-chemical properties. It is shown that the data obtained by numerical Monte Carlo simulation are in good agreement with experimental results indicating adequacy of the developed model of the aorta autofluorescence.

Variations in local elastic modulus along the length of the aorta as observed by use of a scanning haptic microscope (SHM).

PubMed

Moriwaki, Takeshi; Oie, Tomonori; Takamizawa, Keiichi; Murayama, Yoshinobu; Fukuda, Toru; Omata, Sadao; Kanda, Keiichi; Nakayama, Yasuhide

2011-12-01

Variations in microscopic elastic structures along the entire length of canine aorta were evaluated by use of a scanning haptic microscope (SHM). The total aorta from the aortic arch to the abdominal aorta was divided into 6 approximately equal segments. After embedding the aorta in agar, it was cut into horizontal circumferential segments to obtain disk-like agar portions containing ring-like samples of aorta with flat surfaces (thickness, approximately 1 mm). The elastic modulus and topography of the samples under no-load conditions were simultaneously measured along the entire thickness of the wall by SHM by using a probe with a diameter of 5 μm and a spatial resolution of 2 μm at a rate of 0.3 s/point. The elastic modulus of the wall was the highest on the side of the luminal surface and decreased gradually toward the adventitial side. This tendency was similar to that of the change in the elastin fiber content. During the evaluation of the mid-portion of each tunica media segment, the highest elastic modulus (40.8 ± 3.5 kPa) was identified at the thoracic section of the aorta that had the highest density of elastic fibers. Under no-load conditions, portions of the aorta with high elastin density have a high elastic modulus.

Pressure waves in the aorta during isolated abdominal belt loading: the magnitude, phasing, and attenuation.

PubMed

Arregui-Dalmases, C; Del Pozo, E; Stacey, S; Kindig, M; Lessley, D; Lopez-Valdes, F; Forman, J; Kent, R

2011-07-01

While rupture of the aorta is a leading cause of sudden death following motor vehicle crashes, the specific mechanism that causes this injury is not currently well understood. Aortic ruptures occurring in the field are likely due to a complex combination of contributing factors such as acceleration, compression of the chest, and increased pressure within the aorta. The objective of the current study was to investigate one of these factors in more detail than has been done previously; specifically, to investigate the in situ intra-aortic pressure generated during isolated belt loading to the abdomen. Ten juvenile swine were subjected to dynamic belt loads applied to the abdomen. Intraaortic pressure was measured at multiple locations to assess the magnitude and propagation of the resulting blood pressure wave. The greatest average peak pressure (113.6 +/- 43.5 kPa) was measured in the abdominal aorta. Pressures measured in the thoracic aorta and aortic arch were 70 per cent and 50 per cent, respectively, that measured in the abdominal aorta. No macroscopic aortic trauma was observed. To the authors' knowledge the present study is the first one to document the presence, propagation, and attenuation of a transient pressure wave in the aorta generated by abdominal belt loading. The superiorly moving wave is sufficient to generate hydrostatic and intimal shear stress in the aorta, possibly contributing to the hypothesized mechanisms of traumatic aortic rupture.

Turner Syndrome in Girls Presenting with Coarctation of the Aorta.

PubMed

Eckhauser, Aaron; South, Sarah T; Meyers, Lindsay; Bleyl, Steven B; Botto, Lorenzo D

2015-11-01

To evaluate the frequency of Turner syndrome in a population-based, statewide cohort of girls with coarctation of the aorta. The Utah Birth Defects Network was used to ascertain a cohort of girls between 1997 and 2011 with coarctation of the aorta. Livebirths with isolated coarctation of the aorta or transverse arch hypoplasia were included and patients with complex congenital heart disease not usually seen in Turner syndrome were excluded. Of 244 girls with coarctation of the aorta, 77 patients were excluded, leaving a cohort of 167 girls; 86 patients (51%) had chromosomal studies and 21 (12.6%) were diagnosed with Turner syndrome. All patients were diagnosed within the first 4 months of life and 5 (24%) were diagnosed prenatally. Fifteen patients (71%) had Turner syndrome-related findings in addition to coarctation of the aorta. Girls with mosaicism were less likely to have Turner syndrome-associated findings (3/6 mosaic girls compared with 12/17 girls with non-mosaic 45,X). Twelve girls (57%) diagnosed with Turner syndrome also had a bicommissural aortic valve. At least 12.6% of girls born with coarctation of the aorta have karyotype-confirmed Turner syndrome. Such a high frequency, combined with the clinical benefits of an early diagnosis, supports genetic screening for Turner syndrome in girls presenting with coarctation of the aorta. Copyright © 2015 Elsevier Inc. All rights reserved.

Assessment of the accuracy of AortaScan for detection of abdominal aortic aneurysm (AAA).

PubMed

Abbas, A; Smith, A; Cecelja, M; Waltham, M

2012-02-01

AortaScan AMI 9700 is a portable 3D ultrasound device that automatically measures the maximum diameter of the abdominal aorta without the need for a trained sonographer. It is designed to rapidly diagnose or exclude an AAA and may have particular use in screening programs. Our objective was to determine its accuracy to detect AAA. Subjects from our AAA screening and surveillance programs were examined. The aorta was scanned using the AortaScan and computed tomography (CT). Ninety-one subjects underwent imaging (44 AAA on conventional ultrasound surveillance and 47 controls). The largest measurement obtained by AortaScan was compared against the CT-aortic measurement. The mean aortic diameter was 2.8 cm. The CT scan confirmed the diagnosis of AAA in 43 subjects. There was one false positive measurement on conventional ultrasound. AortaScan missed the diagnosis of AAA in eight subjects. There were thirteen false positive measurements. The sensitivity, specificity, positive and negative predictive values were 81%, 72%, 72% and 81% respectively. A device to detect AAA without the need for a trained operator would have potential in a community-based screening programme. The AortaScan, however, lacks adequate sensitivity and significant technical improvement is necessary before it could be considered a replacement for trained screening personnel. Copyright © 2011 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

The Effect of Chlorpyrifos on Isolated Thoracic Aorta in Rats

PubMed Central

Yıldırım, Ebru; Baydan, Emine; Kanbur, Murat; Kul, Oğuz; Çınar, Miyase; Ekici, Hüsamettin; Atmaca, Nurgül

2013-01-01

This study investigated the effect of chlorpyrifos on thoracic aorta and on the level of NO in plasma and aorta. The effect of chlorpyrifos on thoracic aorta in organ bath was determined in 10 rats. Another 45 rats were assigned to 3 groups with 15 rats each: control group 1 received distilled water, control group 2 was given corn oil, and the last group was given 13.5 mg/kg chlorpyrifos dissolved in corn oil every other day for 8 weeks orally. Chlorpyrifos (10−10 M–10−5 M) showed no effect on isolated thoracic aorta. Plasma AChE activity was decreased, while LDH, ALT, GGT, and AST activities were increased in chlorpyrifos group compared to control groups. Plasma NO level was increased in chlorpyrifos group compared to control groups. iNOS expression was present in all groups in the cytoplasm of the endothelia and in the smooth muscle cells of aorta. According to semiquantitative histomorphological analysis, iNOS immunopositive reactions were seen in the decreasing order in chlorpyrifos, control 2, and control 1 groups. eNOS immunopositive reactions were observed in the endothelial cell cytoplasm, rarely in the subintimal layer, and the smooth muscle cells of aorta. There were no differences among the groups in terms of eNOS immunostaining. In conclusion, chlorpyrifos induced NO production in aorta following an increase in NOS expression. PMID:23878805

The role of nitric oxide synthase in reduced vasocontractile responsiveness induced by prolonged α1-adrenergic receptor stimulation in rat thoracic aorta

PubMed Central

Gürdal, Hakan; Can, Alp; Uğur, Mehmet

2005-01-01

Prolonged exposure (6–12 h) of rat aorta to alpha1-adrenergic receptor (α1AR) agonist phenylephrine (Phe) leads to a decrease in α1AR-mediated vasoconstriction. This reduced responsiveness to α1AR stimulation was strongly dependent on the intactness of the endothelium. We examined the effect of Phe on nitric oxide synthase (NOS) activity by measuring the conversion of [3H]L-arginine to [3H]L-citrulline in rat aorta or in endothelial cells isolated from rat aorta. Phe stimulation increased NOS activity in control aortas. This response was antagonized by prazosin. However, Phe increased neither the activity of NOS nor intracellular Ca2+ in the isolated endothelial cells from the control aortas, whereas acetylcholine (Ach) was able to stimulate both responses in these cells. This result suggests that Phe stimulates α1AR on vascular smooth muscle cells and has an indirect influence on endothelial cells to increase NOS activity. In Phe-exposed aortic rings, basal NOS activity was found to have increased compared to vehicle-exposed control rings. Stimulation with Phe or Ach caused a small increase over basal NOS activity in these preparations. Prolonged exposure to Phe also caused an enhancement of Ach-mediated vasorelaxation in rat aorta. Immunoblot and reverse transcription–polymerase chain reaction experiments showed that prolonged exposure of rat aorta to Phe resulted in an increased expression of eNOS, but not iNOS. This increase was antagonized by nonselective antagonist prazosin. Immunohistochemical staining experiments also showed that expression of eNOS increased in endothelial cells after Phe exposure of the aortas. These results, all together, showed that prolonged exposure of rat aorta to α1AR agonist Phe enhanced the expression of eNOS and basal NOS activity, which probably causes a decreased vasocontractile response to Phe or to other agonists such as 5HT (5-hydroxytryptamine) in rat aorta. This phenomenon can be considered more as a functional antagonism of vasocontractile response to agonists mediated by endothelium than a specific desensitization of α1AR-mediated signalling in vascular smooth muscle cells. PMID:15753950

77 FR 48985 - Notice of Meeting of the ICD-9-CM Coordination and Maintenance Committee

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-15

... Topics: ICD-10 Implementation Announcements Expansion of Thoracic Aorta Body Part Under Heart and Great... from thoracic aorta to abdominal aorta) ICD-10 MS-DRGs ICD-10 HAC Translations ICD-10 MCE Translations...

Effect of atherothrombotic aorta on outcomes of total aortic arch replacement.

PubMed

Okada, Kenji; Omura, Atsushi; Kano, Hiroya; Inoue, Takeshi; Oka, Takanori; Minami, Hitoshi; Okita, Yutaka

2013-04-01

The effect of an atherothrombotic aorta on the short- and long-term outcomes of total aortic arch replacement, including postoperative neurologic deficits, remains unknown. We evaluated this relationship and also elucidated the synergistic effect of multiple other risk factors, in addition to an atherothrombotic aorta, on the neurologic outcome. A group of 179 consecutive patients undergoing total aortic arch replacement were studied. An atherothrombotic aorta was present in 34 patients (19%), more than moderate leukoaraiosis in 71 (39.7%), and significant extracranial carotid artery stenosis in 27 (15.1%). In-hospital deaths occurred in 2 patients, 1 (2.9%) of 34 patients with and 1 (0.7%) of 145 patients without an atherothrombotic aorta (P = .26). Permanent neurologic deficits occurred in 4 (2.2%) and transient neurologic deficits in 17 (9.5%) patients. Multivariate analysis demonstrated that the risk factors for transient neurologic deficits were an atherothrombotic aorta (odds ratio, 4.4), extracranial carotid artery stenosis (odds ratio, 5.5), moderate/severe leukoaraiosis (odds ratio, 3.6), and cardiopulmonary bypass time (odds ratio, 1.02). To calculate the probability of transient neurologic deficits, the following equation was derived: probability of transient neurologic deficits = {1 + exp [7.276 - 1.489 (atherothrombotic aorta) - 1.285 (leukoaraiosis) - 1.701 (extracranial carotid artery stenosis) - 0.017 (cardiopulmonary bypass time)]}(-1). An exponential increase occurred in the probability of transient neurologic deficits with presence of an atherothrombotic aorta and other risk factors in relation to the cardiopulmonary bypass time. Survival at 3 years after surgery was significantly reduced in patients with vs without an atherothrombotic aorta (75.0% ± 8.8% vs 89.2% ± 3.1%, P = .01). Patients with an atherothrombotic aorta and associated preoperative comorbidities might be predisposed to adverse short- and long-term outcomes, including transient neurologic deficits. Copyright © 2013 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Diagnostic performance of focused cardiac ultrasound performed by emergency physicians for the assessment of ascending aorta dilation and aneurysm.

PubMed

Nazerian, Peiman; Vanni, Simone; Morello, Fulvio; Castelli, Matteo; Ottaviani, Maddalena; Casula, Claudia; Petrioli, Alessandra; Bartolucci, Maurizio; Grifoni, Stefano

2015-05-01

The diagnostic performance of transthoracic focused cardiac ultrasound (FoCUS) performed by emergency physicians (EP) to estimate ascending aorta dimensions in the acute setting has not been prospectively studied. The diagnostic accuracy and the interobserver variability of EP-performed FoCUS were investigated to estimate thoracic aortic dilation and aneurysm compared with the results of computed tomography angiography (CTA). This was a prospective single-center cohort study of a convenience sample of patients who underwent CTA in the emergency department for suspected aortic pathology. FoCUS was performed before CTA, and the maximum ascending aorta diameter evaluated in parasternal long-axis view. Aorta diameter < 40 mm by visual estimation or by diameter measurement was considered normal. Measurements were recorded in all patients with aorta diameter ≥ 40 mm. Diagnostic accuracy of FoCUS for detection of aortic dilation (diameter ≥ 40 mm) and aneurysm (diameter ≥ 45 mm) were calculated considering the CTA result as reference standard. In a subgroup of patients, a second EP-sonographer performed FoCUS to evaluate interobserver agreement for the diagnosis of ascending aorta dilation. A total of 140 patients were enrolled in the study. Ascending aorta dilation and aneurysm were detected with FoCUS in 50 (35.7%) and in 27 (17.8%) patients, respectively. Sensitivity and specificity of FoCUS were 78.6% (95% confidence interval [CI] = 65.6% to 88.4%) and 92.9% (95% CI = 85.1% to 97.3%), respectively, for ascending aorta dilation and 64.7% (95% CI = 46.5% to 80.2%) and 95.3% (95% CI = 89.3% to 98.4%), respectively, for ascending aorta aneurysm. Interobserver agreement of FoCUS was k = 0.82. FoCUS performed by EP is specific for ascending aorta dilation and aneurysm when compared to CTA and appears a reproducible technique. © 2015 by the Society for Academic Emergency Medicine.

Fluid Dynamics of Coarctation of the Aorta and Effect of Bicuspid Aortic Valve

PubMed Central

Keshavarz-Motamed, Zahra; Garcia, Julio; Kadem, Lyes

2013-01-01

Up to 80% of patients with coarctation of the aorta (COA) have a bicuspid aortic valve (BAV). Patients with COA and BAV have elevated risks of aortic complications despite successful surgical repair. The development of such complications involves the interplay between the mechanical forces applied on the artery and the biological processes occurring at the cellular level. The focus of this study is on hemodynamic modifications induced in the aorta in the presence of a COA and a BAV. For this purpose, numerical investigations and magnetic resonance imaging measurements were conducted with different configurations: (1) normal: normal aorta and normal aortic valve; (2) isolated COA: aorta with COA (75% reduction by area) and normal aortic valve; (3) complex COA: aorta with the same severity of COA (75% reduction by area) and BAV. The results show that the coexistence of COA and BAV significantly alters blood flow in the aorta with a significant increase in the maximal velocity, secondary flow, pressure loss, time-averaged wall shear stress and oscillatory shear index downstream of the COA. These findings can contribute to a better understanding of why patients with complex COA have adverse outcome even following a successful surgery. PMID:24015239

[Coarctation of the descending aorta. A rare form of connatal aortic stenosis].

PubMed

Stammwitz, E; Schöttler, M; Brix, F; Poser, H L; Langkau, G; Yükseltan, I

1983-07-01

A clinical diagnosis of a coarctation of the aorta was made in a 17-year-old female hypertensive patient. Angiography revealed an atypical stenosis of the descending aorta which was surgically corrected. The causes of aortic stenoses are discussed.

Clinical Study of Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) for Severe Pelvic Fracture and Intra Abdominal Hemorrhagic Shock using Continuous Vital Signs

DTIC Science & Technology

2016-03-01

AWARD NUMBER: W81XWH-15-1-0025 TITLE: Clinical Study of Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) for Severe Pelvic...Intra-Abdominal Hemorrhagic Shock 5b. GRANT NUMBER W81XWH-15-1-0025 Clinical Study of Resuscitative Endovascular Balloon Occlusion of the Aorta ...sites. Resuscitative balloon occlusion of the aorta (REBOA) has been clinically demonstrated to stop bleeding below the diaphragm. It has the potential

Case report: Open replacement of incomplete semi-circular traumatic ruptures of the ascending and descending aorta.

PubMed

Mytsyk, Miroslawa; Grapow, Martin T R; Shahinian, Jasmin; Maurer, Markus; Gurke, Lorenz; Eckstein, Friedrich S

2016-07-16

An incomplete traumatic rupture of the ascending aorta is a rare but life-threatening condition. Hence, the assessment of the extent of the injury prior to therapy is crucial. We report a case of a 50-year-old male with traumatic aortic rupture who underwent emergency surgery after the evaluation of computed tomography scan (CT-scan). The surgical treatment involved replacement of the ascending aorta and stent implantation in descending aorta due to its covered rupture.

Effects of aortic root motion on wall stress in the Marfan aorta before and after personalised aortic root support (PEARS) surgery.

PubMed

Singh, S D; Xu, X Y; Pepper, J R; Izgi, C; Treasure, T; Mohiaddin, R H

2016-07-05

Aortic root motion was previously identified as a risk factor for aortic dissection due to increased longitudinal stresses in the ascending aorta. The aim of this study was to investigate the effects of aortic root motion on wall stress and strain in the ascending aorta and evaluate changes before and after implantation of personalised external aortic root support (PEARS). Finite element (FE) models of the aortic root and thoracic aorta were developed using patient-specific geometries reconstructed from pre- and post-PEARS cardiovascular magnetic resonance (CMR) images in three Marfan patients. The wall and PEARS materials were assumed to be isotropic, incompressible and linearly elastic. A static load on the inner wall corresponding to the patients' pulse pressure was applied. Cardiovascular MR cine images were used to quantify aortic root motion, which was imposed at the aortic root boundary of the FE model, with zero-displacement constraints at the distal ends of the aortic branches and descending aorta. Measurements of the systolic downward motion of the aortic root revealed a significant reduction in the axial displacement in all three patients post-PEARS compared with its pre-PEARS counterparts. Higher longitudinal stresses were observed in the ascending aorta when compared with models without the root motion. Implantation of PEARS reduced the longitudinal stresses in the ascending aorta by up to 52%. In contrast, the circumferential stresses at the interface between the supported and unsupported aorta were increase by up to 82%. However, all peak stresses were less than half the known yield stress for the dilated thoracic aorta. Copyright © 2016 Elsevier Ltd. All rights reserved.

A penetrating atherosclerotic ulcer rupture in the ascending aorta with hemopericardium: a case report.

PubMed

Liu, Yuan-Hao; Ke, Hung-Yen; Lin, Yi-Chang; Tsai, Chien-Sung

2016-07-11

Acute aortic syndrome, including classic aortic dissection, intramural aortic hematoma, and penetrating atherosclerotic ulcer (PAU), is a term used to describe a group of conditions with similar clinical symptoms, but with different pathophysiological mechanisms. PAU is a lesion that penetrates the internal elastic lamina through the media. It is usually located in the descending aorta and rarely observed in the ascending aorta. A 76-year-old man with a history of essential hypertension was brought to the emergency department (ED) because of a sudden-onset chest pain at rest. He had not been taking his medication as ordered. His vital signs in the ED were a blood pressure of 82/60 mmHg, heart rate of 158 beats per min, respiratory rate of 22 breaths per min, and a body temperature of 37.2 °C. An electrocardiogram did not show an ST segment elevation, and cardiac enzymes were within normal limits. No widening mediastinum was found on chest radiography, but a large pericardial effusion with an impending cardiac tamponade was revealed on echocardiography. The diagnosis of PAU rupture in the ascending aorta with hemopericardium was made with chest computed tomography. An emergent sternotomy and ascending aorta reconstruction were performed. A ruptured ulcerative plaque through the intima to the adventitia without flap dissection in the ascending aorta was confirmed. The patient was discharged 18 days after the operation. Although PAU in the ascending aorta is uncommon, it is commonly lethal when it ruptures. With the current advances in endovascular techniques and devices, endovascular repair of PAU in the ascending aorta is currently recommended only for high-risk patients unsuitable for open repair. However, we anticipate that endovascular repair may become feasible in patients with PAU in the ascending aorta in the future.

Automatic identification of origins of left and right coronary arteries in CT angiography for coronary arterial tree tracking and plaque detection

NASA Astrophysics Data System (ADS)

Zhou, Chuan; Chan, Heang-Ping; Chightai, Aamer; Wei, Jun; Hadjiiski, Lubomir M.; Agarwal, Prachi; Kuriakose, Jean W.; Kazerooni, Ella A.

2013-03-01

Automatic tracking and segmentation of the coronary arterial tree is the basic step for computer-aided analysis of coronary disease. The goal of this study is to develop an automated method to identify the origins of the left coronary artery (LCA) and right coronary artery (RCA) as the seed points for the tracking of the coronary arterial trees. The heart region and the contrast-filled structures in the heart region are first extracted using morphological operations and EM estimation. To identify the ascending aorta, we developed a new multiscale aorta search method (MAS) method in which the aorta is identified based on a-priori knowledge of its circular shape. Because the shape of the ascending aorta in the cCTA axial view is roughly a circle but its size can vary over a wide range for different patients, multiscale circularshape priors are used to search for the best matching circular object in each CT slice, guided by the Hausdorff distance (HD) as the matching indicator. The location of the aorta is identified by finding the minimum HD in the heart region over the set of multiscale circular priors. An adaptive region growing method is then used to extend the above initially identified aorta down to the aortic valves. The origins at the aortic sinus are finally identified by a morphological gray level top-hat operation applied to the region-grown aorta with morphological structuring element designed for coronary arteries. For the 40 test cases, the aorta was correctly identified in 38 cases (95%). The aorta can be grown to the aortic root in 36 cases, and 36 LCA origins and 34 RCA origins can be identified within 10 mm of the locations marked by radiologists.

Analysis of the influences of short-term levosimendan exposure on oxidant/antioxidant status and trace-element levels in the physiological status of the thoracic aorta of rats.

PubMed

Aydin, Cemalettin; Ay, Yasin; Basel, Halil; Kavak, Servet; Inan, Bekir; Bektaş, Hava; Gümrükçüoğlu, Hasan Ali; Ekim, Hasan; Demir, Halit

2012-12-01

The objective of this study was to evaluate the effect of levosimendan (chemical formula C₁₄H₁₂N₆O) exposure on oxidant/antioxidant status and trace-element levels in the thoracic aorta of rats. Eighteen male Wistar albino rats were randomly divided into two groups of eight animals each. Group 1 was not exposed to levosimendan and served as a control. Levosimendan (12 μg/kg) diluted in 10 ml 0.5 % dextrose was administered intraperitoneally to group 2. Animals of both groups were killed after 3 days, and their thoracic aortae were harvested for determination of changes in tissue oxidant/antioxidant status and trace-element levels. The animals in both groups were killed 72 h after levosimendan exposure, and thoracic aortae were harvested for determination of the lipid peroxidation product MDA and antioxidant GSH levels and the activities of antioxidant enzymes such as SOD, GSH-Px and CAT. It was found that MDA, GSH and CAT enzyme levels increased in thoracic aortae of rats after levosimendan administration. SOD and CA enzyme activities and the level of antioxidant GSH decreased in thoracic aortae of rats after levosimendan treatment. Pb, Cd and Fe levels of thoracic aortae were significantly higher (P < 0.001) and Mg, Mn, Zn and Cu were significantly lower (P < 0.001) in the levosimendan group compared to the control group. These results suggest that short-term levosimendan treatment caused an increase in free radical production and a decrease in antioxidant enzyme activity in thoracic aortae of levosimendan-treated rats. It also causes a decrease or increase in many mineral levels of the thoracic aorta, which is an undesirable condition for normal pharmacological function.

p38 mitogen-activated protein kinase is involved in arginase-II-mediated eNOS-Uncoupling in Obesity

PubMed Central

2014-01-01

Background Endothelial nitric oxide synthase (eNOS)-uncoupling links obesity-associated insulin resistance and type-II diabetes to the increased incidence of cardiovascular disease. Studies have indicated that increased arginase is involved in eNOS-uncoupling through competing with the substrate L-arginine. Given that arginase-II (Arg-II) exerts some of its biological functions through crosstalk with signal transduction pathways, and that p38 mitogen-activated protein kinase (p38mapk) is involved in eNOS-uncoupling, we investigated here whether p38mapk is involved in Arg-II-mediated eNOS-uncoupling in a high fat diet (HFD)-induced obesity mouse model. Methods Obesity was induced in wild type (WT) and Arg-II-deficient (Arg-II-/-) mice on C57BL/6 J background by high-fat diet (HFD, 55% fat) for 14 weeks starting from age of 7 weeks. The entire aortas were isolated and subjected to 1) immunoblotting analysis of the protein level of eNOS, Arg-II and p38mapk activation; 2) arginase activity assay; 3) endothelium-dependent and independent vasomotor responses; 4) en face staining of superoxide anion and NO production with Dihydroethidium and 4,5-Diaminofluorescein Diacetate, respectively, to assess eNOS-uncoupling. To evaluate the role of p38mapk, isolated aortas were treated with p38mapk inhibitor SB203580 (10 μmol/L, 1 h) prior to the analysis. In addition, the role of p38mapk in Arg-II-induced eNOS-uncoupling was investigated in cultured human endothelial cells overexpressing Arg-II in the absence or presence of shRNA against p38mapk. Results HFD enhanced Arg-II expression/activity and p38mapk activity, which was associated with eNOS-uncoupling as revealed by decreased NO and enhanced L-NAME-inhibitable superoxide in aortas of WT obese mice. In accordance, WT obese mice revealed decreased endothelium-dependent relaxations to acetylcholine despite of higher eNOS protein level, whereas Arg-II-/- obese mice were protected from HFD-induced eNOS-uncoupling and endothelial dysfunction, which was associated with reduced p38mapk activation in aortas of the Arg-II-/- obese mice. Moreover, overexpression of Arg-II in human endothelial cells caused eNOS-uncoupling and augmented p38mapk activation. The Arg-II-induced eNOS-uncoupling was prevented by silencing p38mapk. Furthermore, pharmacological inhibition of p38mapk recouples eNOS in isolated aortas from WT obese mice. Conclusions Taking together, we demonstrate here for the first time that Arg-II causes eNOS-uncoupling through activation of p38 mapk in HFD-induced obesity. PMID:25034973

Effect of coarctation of the aorta and bicuspid aortic valve on flow dynamics and turbulence in the aorta using particle image velocimetry

NASA Astrophysics Data System (ADS)

Keshavarz-Motamed, Zahra; Garcia, Julio; Gaillard, Emmanuel; Maftoon, Nima; Di Labbio, Giuseppe; Cloutier, Guy; Kadem, Lyes

2014-03-01

Blood flow in the aorta has been of particular interest from both fluid dynamics and physiology perspectives. Coarctation of the aorta (COA) is a congenital heart disease corresponding to a severe narrowing in the aortic arch. Up to 85 % of patients with COA have a pathological aortic valve, leading to a narrowing at the valve level. The aim of the present work was to advance the state of understanding of flow through a COA to investigate how narrowing in the aorta (COA) affects the characteristics of the velocity field and, in particular, turbulence development. For this purpose, particle image velocimetry measurements were conducted at physiological flow and pressure conditions, with three different aorta configurations: (1) normal case: normal aorta + normal aortic valve; (2) isolated COA: COA (with 75 % reduction in aortic cross-sectional area) + normal aortic valve and (3) complex COA: COA (with 75 % reduction in aortic cross-sectional area) + pathological aortic valve. Viscous shear stress (VSS), representing the physical shear stress, Reynolds shear stress (RSS), representing the turbulent shear stress, and turbulent kinetic energy (TKE), representing the intensity of fluctuations in the fluid flow environment, were calculated for all cases. Results show that, compared with a healthy aorta, the instantaneous velocity streamlines and vortices were deeply changed in the presence of the COA. The normal aorta did not display any regions of elevated VSS, RSS and TKE at any moment of the cardiac cycle. The magnitudes of these parameters were elevated for both isolated COA and complex COA, with their maximum values mainly being located inside the eccentric jet downstream of the COA. However, the presence of a pathologic aortic valve, in complex COA, amplifies VSS (e.g., average absolute peak value in the entire aorta for a total flow of 5 L/min: complex COA: = 36 N/m2; isolated COA = 19 N/m2), RSS (e.g., average peak value in the entire aorta for a total flow of 5 L/min: complex COA: = 84.6 N/m2; isolated COA = 44 N/m2) and TKE (e.g., average peak value in the entire aorta for a total flow of 5 L/min: complex COA: = 215 N/m2; isolated COA = 100 N/m2). This demonstrates that the pathological aortic valve strongly interacts with the COA. Findings of this study indicate that the presence of both a COA and a pathological aortic valve significantly alters hemodynamics in the aorta and thus might contribute to the progression of the disease in this region. This study can partially explain the complications associated in patients with COA, in the presence of a pathological aortic valve and the consequent adverse outcome post-surgery.

Thermographic study of laser on arteries.

PubMed

Mnitentag, J; Marques, E F; Ribeiro, M P; Braga, G A; Navarro, M R; Veratti, A B; Armelin, E; Macruz, R; Jatene, A D

1987-01-01

We analyzed the different effects of CO2, Nd-YAG, and argon lasers on aorta by using a Thermovision infrared system that registered the laser interaction with mongrel dog aorta. The images (thermograms) obtained were processed by a computer, which associated each area of the same temperature with a determined color. These thermograms were compared to histological analysis of the respective samples and the following results were obtained: (1) After the application of each laser there is very little propagation of heat in tissue. (2) The CO2 laser makes tissue reach 100 degrees C in less than 0.05 seconds. (3) The heat dissipation time was higher with the Nd-YAG laser due to higher scattering on tissue. Based on this research we conclude that the CO2 laser was best absorbed, the Nd-YAG laser penetrated human tissue with the best results, and the argon laser had the most significant backscattering.

MRI Artifacts of a Metallic Stent Derived From a Human Aorta Specimen

DOE Office of Scientific and Technical Information (OSTI.GOV)

Soto, M. E.; Flores, P.; Marrufo, O.

Magnetic resonance imaging has proved to be a useful technique to get images of the whole body. However, the presence of ferromagnetic material can cause susceptibility artifacts, which result from microscopic gradients that occur near the boundaries between areas displaying different magnetic susceptibility. These gradients cause dephasing of spins and frequency shifts in the surrounding tissues. Intravoxel dephasing and spatial mis-registration can degrade image quality. An aorta with a metallic stent was preserved in formaldehyde at 10% inside acrylic cylinders and used to obtain MR images. We tested pulsed spin echo and gradient echo sequences to improve image quality. Allmore » experiments were performed on a 7T/21 cm Varian system (Varian, Inc, Palo Alto, CA) equipped with Direct Drive technology and a 16-rung birdcage coil transceiver. The presence of metallic stents produces a lack of signal that might give falsely reassuring appearances within the vessel lumen.« less

A wave dynamics criterion for optimization of mammalian cardiovascular system.

PubMed

Pahlevan, Niema M; Gharib, Morteza

2014-05-07

The cardiovascular system in mammals follows various optimization criteria covering the heart, the vascular network, and the coupling of the two. Through a simple dimensional analysis we arrived at a non-dimensional number (wave condition number) that can predict the optimum wave state in which the left ventricular (LV) pulsatile power (LV workload) is minimized in a mammalian cardiovascular system. This number is also universal among all mammals independent of animal size maintaining a value of around 0.1. By utilizing a unique in vitro model of human aorta, we tested our hypothesis against a wide range of aortic compliance (pulse wave velocity). We concluded that the optimum value of the wave condition number remains to be around 0.1 for a wide range of aorta compliance that we could simulate in our in-vitro system. Copyright © 2014 Elsevier Ltd. All rights reserved.

Role of aldehyde dehydrogenase in hypoxic vasodilator effects of nitrite in rats and humans

PubMed Central

Arif, Sayqa; Borgognone, Alessandra; Lin, Erica Lai-Sze; O'Sullivan, Aine G; Sharma, Vishal; Drury, Nigel E; Menon, Ashvini; Nightingale, Peter; Mascaro, Jorge; Bonser, Robert S; Horowitz, John D; Feelisch, Martin; Frenneaux, Michael P; Madhani, Melanie

2015-01-01

Background and Purpose Hypoxic conditions favour the reduction of nitrite to nitric oxide (NO) to elicit vasodilatation, but the mechanism(s) responsible for bioconversion remains ill defined. In the present study, we assess the role of aldehyde dehydrogenase 2 (ALDH2) in nitrite bioactivation under normoxia and hypoxia in the rat and human vasculature. Experimental Approach The role of ALDH2 in vascular responses to nitrite was studied using rat thoracic aorta and gluteal subcutaneous fat resistance vessels from patients with heart failure (HF; 16 patients) in vitro and by measurement of changes in forearm blood flow (FBF) during intra-arterial nitrite infusion (21 patients) in vivo. Specifically, we investigated the effects of (i) ALDH2 inhibition by cyanamide or propionaldehyde and the (ii) tolerance-independent inactivation of ALDH2 by glyceryl trinitrate (GTN) on the vasodilator activity of nitrite. In each setting, nitrite effects were measured via evaluation of the concentration–response relationship under normoxic and hypoxic conditions in the absence or presence of ALDH2 inhibitors. Key Results Both in rat aorta and human resistance vessels, dilatation to nitrite was diminished following ALDH2 inhibition, in particular under hypoxia. In humans there was a non-significant trend towards attenuation of nitrite-mediated increases in FBF. Conclusions and Implications In human and rat vascular tissue in vitro, hypoxic nitrite-mediated vasodilatation involves ALDH2. In patients with HF in vivo, the role of this enzyme in nitrite bioactivation is at the most, modest, suggesting the involvement of other more important mechanisms. PMID:25754766

Outflow tract septation and the aortic arch system in reptiles: lessons for understanding the mammalian heart.

PubMed

Poelmann, Robert E; Gittenberger-de Groot, Adriana C; Biermans, Marcel W M; Dolfing, Anne I; Jagessar, Armand; van Hattum, Sam; Hoogenboom, Amanda; Wisse, Lambertus J; Vicente-Steijn, Rebecca; de Bakker, Merijn A G; Vonk, Freek J; Hirasawa, Tatsuya; Kuratani, Shigeru; Richardson, Michael K

2017-01-01

Cardiac outflow tract patterning and cell contribution are studied using an evo-devo approach to reveal insight into the development of aorto-pulmonary septation. We studied embryonic stages of reptile hearts (lizard, turtle and crocodile) and compared these to avian and mammalian development. Immunohistochemistry allowed us to indicate where the essential cell components in the outflow tract and aortic sac were deployed, more specifically endocardial, neural crest and second heart field cells. The neural crest-derived aorto-pulmonary septum separates the pulmonary trunk from both aortae in reptiles, presenting with a left visceral and a right systemic aorta arising from the unseptated ventricle. Second heart field-derived cells function as flow dividers between both aortae and between the two pulmonary arteries. In birds, the left visceral aorta disappears early in development, while the right systemic aorta persists. This leads to a fusion of the aorto-pulmonary septum and the aortic flow divider (second heart field population) forming an avian aorto-pulmonary septal complex. In mammals, there is also a second heart field-derived aortic flow divider, albeit at a more distal site, while the aorto-pulmonary septum separates the aortic trunk from the pulmonary trunk. As in birds there is fusion with second heart field-derived cells albeit from the pulmonary flow divider as the right 6th pharyngeal arch artery disappears, resulting in a mammalian aorto-pulmonary septal complex. In crocodiles, birds and mammals, the main septal and parietal endocardial cushions receive neural crest cells that are functional in fusion and myocardialization of the outflow tract septum. Longer-lasting septation in crocodiles demonstrates a heterochrony in development. In other reptiles with no indication of incursion of neural crest cells, there is either no myocardialized outflow tract septum (lizard) or it is vestigial (turtle). Crocodiles are unique in bearing a central shunt, the foramen of Panizza, between the roots of both aortae. Finally, the soft-shell turtle investigated here exhibits a spongy histology of the developing carotid arteries supposedly related to regulation of blood flow during pharyngeal excretion in this species. This is the first time that is shown that an interplay of second heart field-derived flow dividers with a neural crest-derived cell population is a variable but common, denominator across all species studied for vascular patterning and outflow tract septation. The observed differences in normal development of reptiles may have impact on the understanding of development of human congenital outflow tract malformations.

An Abdominal Aorta Wall Extraction for Liver Cirrhosis Classification Using Ultrasonic Images

NASA Astrophysics Data System (ADS)

Hayashi, Takaya; Fujita, Yusuke; Mitani, Yoshihiro; Hamamoto, Yoshihiko; Segawa, Makoto; Terai, Shuji; Sakaida, Isao

2011-06-01

We propose a method to extract an abdominal aorta wall from an M-mode image. Furthermore, we propose the use of a Gaussian filter in order to improve image quality. The experimental results show that the Gaussian filter is effective in the abdominal aorta wall extraction.

Co-existence of severe coarctation of the aorta and aortic valve stenosis in a 65-year-old woman: a case report.

PubMed

Onohara, Daisuke; Sato, Aiko; Tasaki, Yuichi; Yamada, Takafumi

2014-01-01

Coarctation of the aorta is usually diagnosed and corrected early in life. Survival to more than 60 years of age of a patient with unrepaired coarctation of the aorta is extremely unusual, and the optimal management strategies for such patients are controversial. We describe the case of a woman who was first diagnosed as having coarctation of the aorta and aortic valve stenosis at the age of 65 years and underwent successful aortic valve replacement.

Pathologic aneurysmal dilation of the ascending aorta and dilation of the main pulmonary artery in patients with Kabuki syndrome: valve-sparing aortic root replacement.

PubMed

Dyamenahalli, Umesh; Abraham, Boban; Fontenot, Eudice; Prasad, Vinay; Imamura, Michiaki

2007-01-01

We report the aneurysmal dilation of the ascending aorta and the main pulmonary artery in 2 children with Kabuki syndrome. In 1 patient, there was progressive aneurysmal dilation of the ascending aorta necessitating aortoplasty. Histologic examination of the resected aorta revealed disrupted and fragmented elastic fibers in the medial layer, along with mucinous degeneration of the aortic wall. This is the first recognition and report of these findings as part of the Kabuki syndrome.

Measuring, Reversing, and Modeling the Mechanical Changes Due to the Absence of Fibulin-4 in Mouse Arteries

PubMed Central

Le, Victoria P.; Yamashiro, Yoshito; Yanagisawa, Hiromi; Wagenseil, Jessica E.

2014-01-01

Mice with a smooth muscle cell (SMC) specific deletion of fibulin-4 (SMKO) show decreased expression of SMC contractile genes, decreased circumferential compliance, and develop aneurysms in the ascending aorta. Neonatal administration of drugs that inhibit the angiotensin II pathway encourage expression of contractile genes and prevent aneurysm development, but do not increase compliance in SMKO aorta. We hypothesized that multidimensional mechanical changes in the aorta and/or other elastic arteries may contribute to aneurysm pathophysiology. We found that the SMKO ascending aorta and carotid artery showed mechanical changes in the axial direction. These changes were not reversed by angiotensin II inhibitors, hence reversing the axial changes is not required for aneurysm prevention. Mechanical changes in the circumferential direction were specific to the ascending aorta, therefore mechanical changes in the carotid do not contribute to aortic aneurysm development. We also hypothesized that a published model of postnatal aortic growth and remodeling could be used to investigate mechanisms behind the changes in SMKO aorta and aneurysm development over time. Dimensions and mechanical behavior of adult SMKO aorta were reproduced by the model after modifying the initial component material constants and the aortic dilation with each postnatal time step. The model links biological observations to specific mechanical responses in aneurysm development and treatment. PMID:24526456

Measuring, reversing, and modeling the mechanical changes due to the absence of Fibulin-4 in mouse arteries.

PubMed

Le, Victoria P; Yamashiro, Yoshito; Yanagisawa, Hiromi; Wagenseil, Jessica E

2014-10-01

Mice with a smooth muscle cell (SMC)-specific deletion of Fibulin-4 (SMKO) show decreased expression of SMC contractile genes, decreased circumferential compliance, and develop aneurysms in the ascending aorta. Neonatal administration of drugs that inhibit the angiotensin II pathway encourages the expression of contractile genes and prevents aneurysm development, but does not increase compliance in SMKO aorta. We hypothesized that multidimensional mechanical changes in the aorta and/or other elastic arteries may contribute to aneurysm pathophysiology. We found that the SMKO ascending aorta and carotid artery showed mechanical changes in the axial direction. These changes were not reversed by angiotensin II inhibitors, hence reversing the axial changes is not required for aneurysm prevention. Mechanical changes in the circumferential direction were specific to the ascending aorta; therefore, mechanical changes in the carotid do not contribute to aortic aneurysm development. We also hypothesized that a published model of postnatal aortic growth and remodeling could be used to investigate mechanisms behind the changes in SMKO aorta and aneurysm development over time. Dimensions and mechanical behavior of adult SMKO aorta were reproduced by the model after modifying the initial component material constants and the aortic dilation with each postnatal time step. The model links biological observations to specific mechanical responses in aneurysm development and treatment.

Ascending aortic elongation and the risk of dissection.

PubMed

Krüger, Tobias; Forkavets, Oksana; Veseli, Kujtim; Lausberg, Henning; Vöhringer, Luise; Schneider, Wilke; Bamberg, Fabian; Schlensak, Christian

2016-08-01

Unlike aneurysm formation, the role of ascending aortic elongation in the pathogenesis of Type A aortic dissection (TAD) is largely unclear. We investigated the morphology of healthy, dissected and predissection aortas with a focus on ascending aortic length. We retrospectively compared clinical and computer tomography angiography (CTA) data from TAD patients (n = 130), patients who developed a TAD in the further clinical course (preTAD, n = 16) and healthy control patients who received a CTA for non-aortic emergencies (n = 165). The length of the ascending aorta was defined as the distance between the sinotubular junction (STJ) and the brachiocephalic trunk (BCT) at the central line, the outer and inner curvature as well as the direct distance in the frontal and sagittal planes. Additionally, the aortic diameters were analysed. In the healthy controls, we found a positive correlation of age with the aortic diameter (r = 0.57) and aortic length (r = 0.42). The correlation of the respective parameters with the body size was negligible (r < 0.2). The median ascending aortic diameter at the height of the pulmonary artery in TAD (50 mm) was significantly (P < 0.001) larger compared with the respective diameter of the healthy aortas (34 mm). The diameter of the preTAD aortas (40 mm) was also significantly larger compared with the healthy controls. These proportions were similar in all the aortic diameters. The midline length of the healthy ascending aortas was 71 mm. In the preTAD and TAD aortas, the same values were 81 mm and 92 mm, respectively (both P < 0.001). We evaluated the linear distance between the STJ and the BCT in the frontal plane as an easy-to-measure parameter of aortic length. In the TAD aortas (108 mm) and preTAD aortas (97 mm), this distance was significantly longer compared with the healthy aortas (84 mm). Aortic diameter might not be an optimal parameter to predict dissection. Most aortas dissect at diameters below 55 mm. Both the TAD and preTAD aortas were elongated compared with the healthy controls. Thus, aortic elongation may play a role in the pathogenesis of and may be a risk factor for TAD. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Resolving Low-Density Lipoprotein (LDL) on the Human Aortic Surface Using Large Eddy Simulation

NASA Astrophysics Data System (ADS)

Lantz, Jonas; Karlsson, Matts

2011-11-01

The prediction and understanding of the genesis of vascular diseases is one of the grand challenges in biofluid engineering. The progression of atherosclerosis is correlated to the build- up of LDL on the arterial surface, which is affected by the blood flow. A multi-physics simulation of LDL mass transport in the blood and through the arterial wall of a subject specific human aorta was performed, employing a LES turbulence model to resolve the turbulent flow. Geometry and velocity measurements from magnetic resonance imaging (MRI) were incorporated to assure physiological relevance of the simulation. Due to the turbulent nature of the flow, consecutive cardiac cycles are not identical, neither in vivo nor in the simulations. A phase average based on a large number of cardiac cycles is therefore computed, which is the proper way to get reliable statistical results from a LES simulation. In total, 50 cardiac cycles were simulated, yielding over 2.5 Billion data points to be post-processed. An inverse relation between LDL and WSS was found; LDL accumulated on locations where WSS was low and vice-versa. Large temporal differences were present, with the concentration level decreasing during systolic acceleration and increasing during the deceleration phase. This method makes it possible to resolve the localization of LDL accumulation in the normal human aorta with its complex transitional flow.

Nicotinamide Riboside Preserves Cardiac Function in a Mouse Model of Dilated Cardiomyopathy.

PubMed

Diguet, Nicolas; Trammell, Samuel A J; Tannous, Cynthia; Deloux, Robin; Piquereau, Jérôme; Mougenot, Nathalie; Gouge, Anne; Gressette, Mélanie; Manoury, Boris; Blanc, Jocelyne; Breton, Marie; Decaux, Jean-François; Lavery, Gareth G; Baczkó, István; Zoll, Joffrey; Garnier, Anne; Li, Zhenlin; Brenner, Charles; Mericskay, Mathias

2018-05-22

Myocardial metabolic impairment is a major feature in chronic heart failure. As the major coenzyme in fuel oxidation and oxidative phosphorylation and a substrate for enzymes signaling energy stress and oxidative stress response, nicotinamide adenine dinucleotide (NAD + ) is emerging as a metabolic target in a number of diseases including heart failure. Little is known on the mechanisms regulating homeostasis of NAD + in the failing heart. To explore possible alterations of NAD + homeostasis in the failing heart, we quantified the expression of NAD + biosynthetic enzymes in the human failing heart and in the heart of a mouse model of dilated cardiomyopathy (DCM) triggered by Serum Response Factor transcription factor depletion in the heart (SRF HKO ) or of cardiac hypertrophy triggered by transverse aorta constriction. We studied the impact of NAD + precursor supplementation on cardiac function in both mouse models. We observed a 30% loss in levels of NAD + in the murine failing heart of both DCM and transverse aorta constriction mice that was accompanied by a decrease in expression of the nicotinamide phosphoribosyltransferase enzyme that recycles the nicotinamide precursor, whereas the nicotinamide riboside kinase 2 (NMRK2) that phosphorylates the nicotinamide riboside precursor is increased, to a higher level in the DCM (40-fold) than in transverse aorta constriction (4-fold). This shift was also observed in human failing heart biopsies in comparison with nonfailing controls. We show that the Nmrk2 gene is an AMP-activated protein kinase and peroxisome proliferator-activated receptor α responsive gene that is activated by energy stress and NAD + depletion in isolated rat cardiomyocytes. Nicotinamide riboside efficiently rescues NAD + synthesis in response to FK866-mediated inhibition of nicotinamide phosphoribosyltransferase and stimulates glycolysis in cardiomyocytes. Accordingly, we show that nicotinamide riboside supplementation in food attenuates the development of heart failure in mice, more robustly in DCM, and partially after transverse aorta constriction, by stabilizing myocardial NAD + levels in the failing heart. Nicotinamide riboside treatment also robustly increases the myocardial levels of 3 metabolites, nicotinic acid adenine dinucleotide, methylnicotinamide, and N1-methyl-4-pyridone-5-carboxamide, that can be used as validation biomarkers for the treatment. The data show that nicotinamide riboside, the most energy-efficient among NAD precursors, could be useful for treatment of heart failure, notably in the context of DCM, a disease with few therapeutic options. © 2017 American Heart Association, Inc.

Mechanics of blood supply to the heart: wave reflection effects in a right coronary artery.

PubMed Central

Zamir, M

1998-01-01

Mechanics of blood flow in the coronary circulation have in the past been based largely on models in which the detailed architecture of the coronary network is not included because of lack of data: properties of individual vessels do not appear individually in the model but are represented collectively by the elements of a single electric circuit. Recent data from the human heart make it possible, for the first time, to examine the dynamics of flow in the coronary network based on detailed, measured vascular architecture. In particular, admittance values along the full course of the right coronary artery are computed based on actual lengths and diameters of the many thousands of branches which make up the distribution system of this vessel. The results indicate that effects of wave reflections on this flow are far more significant than those generally suspected to occur in coronary blood flow and that they are actually the reverse of the well known wave reflection effects in the aorta. PMID:9523440

A theory for water and macromolecular transport in the pulmonary artery wall with a detailed comparison to the aorta

PubMed Central

Zeng, Zhongqing; Jan, Kung-Ming

2012-01-01

The pulmonary artery (PA) wall, which has much higher hydraulic conductivity and albumin void space and approximately one-sixth the normal transmural pressure of systemic arteries (e.g, aorta, carotid arteries), is rarely atherosclerotic, except under pulmonary hypertension. This study constructs a detailed, two-dimensional, wall-structure-based filtration and macromolecular transport model for the PA to investigate differences in prelesion transport processes between the disease-susceptible aorta and the relatively resistant PA. The PA and aorta models are similar in wall structure, but very different in parameter values, many of which have been measured (and therefore modified) since the original aorta model of Huang et al. (23). Both PA and aortic model simulations fit experimental data on transwall LDL concentration profiles and on the growth of isolated endothelial (horseradish peroxidase) tracer spots with circulation time very well. They reveal that lipid entering the aorta attains a much higher intima than media concentration but distributes better between these regions in the PA than aorta and that tracer in both regions contributes to observed tracer spots. Solutions show why both the overall transmural water flow and spot growth rates are similar in these vessels despite very different material transport parameters. Since early lipid accumulation occurs in the subendothelial intima and since (matrix binding) reaction kinetics depend on reactant concentrations, the lower intima lipid concentrations in the PA vs. aorta likely lead to slower accumulation of bound lipid in the PA. These findings may be relevant to understanding the different atherosusceptibilities of these vessels. PMID:22198178

Cardiovascular Involvement in Children with Osteogenesis Imperfecta

PubMed Central

Karamifar, Hamdollah; Ilkhanipoor, Homa; Ajami, Gholamhossein; Karamizadeh, Zohreh; Amirhakimi, Gholamhossein; Shakiba, Ali-Mohammad

2013-01-01

Objective Osteogenesis imperfecta is a hereditary disease resulting from mutation in type I procollagen genes. One of the extra skeletal manifestations of this disease is cardiac involvement. The prevalence of cardiac involvement is still unknown in the children with osteogenesis imperfecta. The present study aimed to investigate the prevalence of cardiovascular abnormalities in these patients. Methods 24 children with osteogenesis imperfecta and 24 normal children who were matched with the patients regarding sex and age were studied. In both groups, standard echocardiography was performed, and heart valves were investigated. Dimensions of left ventricle, aorta annulus, sinotubular junction, ascending and descending aorta were measured and compared between the two groups. Findings The results revealed no significant difference between the two groups regarding age, sex, ejection fraction, shortening fraction, mean of aorta annulus, sinotubular junction, ascending and descending aorta, but after correction based on the body surface area, dimensions of aorta annulus, sinotubular junction, ascending and descending aorta in the patients were significantly higher than those in the control group (P<0.05). Two (8.3%) patients had aortic insufficiency and five (20%) patients had tricuspid regurgitation, three of whom had gradient >25 mmHg and one patient had pulmonary insufficiency with indirect evidence of pulmonary hypertension. According to Z scores of aorta annulus, sinotubular junction and ascending aorta, 5, 3, and 1 out of 24 patients had Z scores >2 respectively. Conclusion The prevalence of valvular heart diseases and aortic root dilation was higher in children with osteogenesis imperfecta. In conclusion, cardiovascular investigation is recommended in these children. PMID:24800009

77 FR 61768 - Neurological Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-11

... vasculature via partial occlusion of the descending aorta, including in patients with acute ischemic stroke... device is placed in the descending aorta. On March 30, 2005, a Humanitarian Device Exemption application... selectively stopping or controlling flow in the peripheral vasculature, which includes the descending aorta...

Exploring inside a shaggy aorta using non-obstructive angioscopy.

PubMed

Komatsu, Sei; Takahashi, Satoru; Toyama, Yasuyuki; Kodama, Kazuhisa

2017-05-22

A shaggy aorta is reportedly related to atheromatous embolisation, which causes serious ischaemic damage to various organs. However, its characteristics are poorly understood. Non-obstructive angioscopy (NOA) has been developed to safely detect aortic plaques and injuries. A 70-year-old woman who was found to have a shaggy aorta on CT angiography underwent NOA for precise evaluation of vulnerable aortic plaques and injuries inside the aorta. Vulnerable aortic plaques included puff-like ruptures, chandelier-like ruptures and erosions seen throughout the aorta. Aortic injuries included flaps, slits, subintimal bleeding, dissection and multilayered partitions. The patient had no embolic symptoms or an elevated eosinophil count, estimated glomerular filtration rate or C reactive protein level, compared with the baseline. Various changes in spontaneous vulnerable plaques and injuries inside the aorta that were not apparent on CT were safely revealed on NOA. Thus, NOA may reveal findings indicative of spontaneous and postoperative atheromatous embolisation. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Flow Dynamics of Contrast Dispersion in the Aorta

NASA Astrophysics Data System (ADS)

Eslami, Parastou; Seo, Jung-Hee; Chen, Marcus; Mittal, Rajat

2016-11-01

The time profile of the contrast concentration or arterial input function (AIF) has many fundamental clinical implications and is of importance for many imaging modalities and diagnosis such as MR perfusion, CT perfusion and CT angiography (CTA). Contrast dispersion in CTA has been utilized to develop a novel method- Transluminal Attenuation Flow Encoding (TAFE)- to estimate coronary blood flow (CBF). However, in clinical practice, AIF is only available in the descending aorta and is used as a surrogate of the AIF at the coronary ostium. In this work we use patient specific computational models of the complete aorta to investigate the fluid dynamics of contrast dispersion in the aorta. The simulation employs a realistic kinematic model of the aortic valve and the dispersion patterns are correlated with the complex dynamics of the pulsatile flow in the curved aorta. The simulations allow us to determine the implications of using the descending aorta AIF as a surrogate for the AIF at the coronary ostium. PE is supported by the NIH Individual Partnership Program. -/abstract- Category: 4.7.1: Biological fluid dynamics: Physiological - Cardiovasc This work was done at Johns Hopkins University.

Ascending Aorta to Hepatic and Mesenteric Artery Bypassing, in Patients with Chronic Mesenteric Ischemia and Extensive Aortic Disease-A Case Report and Review of the Literature.

PubMed

Barr, James; Kokotsakis, John; Tsipas, Pantelis; Papapavlou, Prodromos; Velissarios, Konstantinos; Kratimenos, Theodoros; Athanasiou, Thanos

2017-02-01

Chronic mesenteric ischemia (CMI) is a rare disorder caused by severe stenosis of the mesenteric arterial supply that results in postprandial pain and weight loss. Treatment options are surgical or endovascular. Surgical bypass can be performed in an antegrade fashion from the supraceliac abdominal aorta (AA) or the distal descending thoracic aorta or in a retrograde fashion from the infrarenal aorta or the common iliac artery. However, in some patients with disease of the descending thoracic aorta or the AA, another site for the proximal anastomosis needs to be found. In this article, we report the case of a 69-year-old man with a thoracoabdominal aortic aneurysm and CMI in whom we performed bypass grafts to the hepatic and superior mesenteric arteries using the ascending aorta as the site for the proximal anastomoses via a median sternolaparotomy. In addition, we performed a literature review of all similar cases and provide an analysis of this technique and an assessment of the success rates. Copyright © 2016 Elsevier Inc. All rights reserved.

Recirculation zone length in renal artery is affected by flow spirality and renal-to-aorta flow ratio.

PubMed

Javadzadegan, Ashkan; Fulker, David; Barber, Tracie

2017-07-01

Haemodynamic perturbations such as flow recirculation zones play a key role in progression and development of renal artery stenosis, which typically originate at the aorta-renal bifurcation. The spiral nature of aortic blood flow, division of aortic blood flow in renal artery as well as the exercise conditions have been shown to alter the haemodynamics in both positive and negative ways. This study focuses on the combinative effects of spiral component of blood flow, renal-to-aorta flow ratio and the exercise conditions on the size and distribution of recirculation zones in renal branches using computational fluid dynamics technique. Our findings show that the recirculation length was longest when the renal-to-aorta flow ratio was smallest. Spiral flow and exercise conditions were found to be effective in reducing the recirculation length in particular in small renal-to-aorta flow ratios. These results support the hypothesis that in renal arteries with small flow ratios where a stenosis is already developed an artificially induced spiral flow within the aorta may decelerate the progression of stenosis and thereby help preserve kidney function.

Serum lipid profile and inflammatory markers in the aorta of cholesterol-fed rats supplemented with extra virgin olive oil, sunflower oils and oil-products.

PubMed

Katsarou, Ageliki I; Kaliora, Andriana C; Papalois, Apostolos; Chiou, Antonia; Kalogeropoulos, Nick; Agrogiannis, George; Andrikopoulos, Nikolaos K

2015-01-01

Extra virgin olive oil (EVOO) major and minor component anti-inflammatory effect on aorta was evaluated; Wistar rats were fed (9 weeks) on either a high-cholesterol diet (HCD) or a HCD supplemented with oils, i.e. EVOO, sunflower oil (SO), high-oleic sunflower oil (HOSO), or oil-products modified to their phenolic content, i.e. phenolics deprived-EVOO [EVOO(-)], SO enriched with the EVOO phenolics [SO(+)], HOSO enriched with the EVOO phenolics [HOSO(+)]. HCD induced dyslipidemia and resulted in higher aorta adhesion molecules levels at euthanasia. Groups receiving EVOO, EVOO(-), HOSO, HOSO(+) presented higher serum TC and LDL-c levels compared to cholesterol-fed rats; attenuation of aorta E-selectin levels was also observed. In EVOO/EVOO(-) groups, aorta vascular endothelial adhesion molecule-1 (VCAM-1) was lower compared to HCD animals. SO/SO(+) diets had no effect on endothelial dysfunction amelioration. Overall, our results suggest that major and/or minor EVOO constituents improve aorta E-selectin and VCAM-1, while serum lipids do not benefit.

A Numerical Modeling of A Vascular Implantable Cardiac Endovascular Assistant (AVICENA)

NASA Astrophysics Data System (ADS)

Rahmani, Shahrokh; Tehrani, Pedram; Karimi, Alireza; Alizadeh, Mansour; Navidbakhsh, Mahdi

2015-10-01

Cardiovascular diseases have been recently shown to have a pivotal role in human death and endangers lives of many people around the world. One of the most common cardiovascular diseases is poor performance of left ventricle. In this case, the ventricle cannot pump the blood into the aorta and circulatory system with a suitable power which is required for normal circulatory system. AVICENA is a new cardiac assist device which is implanted into the aorta to help the ventricle to pump the blood into circulatory system with more power and to make a better perfusion of the coronary arteries as well. To reach a desire value of rotational speed of the pump, a control circuit is designed for counterpulsation of AVICENA based on the outcomes from previous studies. This control circuit uses a PID controller. The present study aims to simulate the blood flow through the balloon part of AVICENA in a heart cycle with focusing on the calculation of its pump rotational speed by controlling the electrical current of the pump. Results revealed that the desired rotational speed of the pump can be achieved according to the previous aorta pressure cycle by electrical current control which is higher during balloon inflation in comparison with balloon deflation. These findings may have implications not only for understanding the performance of AVICENA but also to help cardiac mechanics experts to improve the shortcoming of this newborn device.

Anomalous Posterior Intercostal Arterial Trunk Arising From the Abdominal Aorta

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jie, Bing, E-mail: jbshh@163.com; Yu, Dong, E-mail: yudong-mail@126.com; Jiang, Sen, E-mail: jasfly77@vip.163.com

A common trunk of the ipsilateral posterior intercostal artery (PIA) arising from the thoracic aorta is usually an anatomical variation. However, a common trunk of bilateral posterior intercostal arterial trunk (PIAT) arising from the abdominal aorta is rare. It is important to recognize this anatomical variation of PIA when performing interventional radiological procedures. We present a rare case of an anomalous PIAT that originated from the abdominal aorta in a patient with hemoptysis caused by tuberculosis sequelae. Bilateral 4th to 11th PIAs arose from a common trunk and the trunk arising from the posterior aspect of the abdominal aorta atmore » the level of T12/L1 intervertebral space. The pathological right 4th and 5th PIAs and bronchial arteries were embolized. Hemoptysis has been controlled for 3 months.« less

Complete occlusion after blunt injury to the abdominal aorta.

PubMed

Meghoo, Colin A L; Gonzalez, Ernest A; Tyroch, Alan H; Wohltmann, Christopher D

2003-10-01

Injury to the abdominal aorta after blunt trauma is uncommon. When this injury results in complete vessel occlusion, the presentation is dramatic. Timely intervention is essential. After a case report, we examined all reported cases of complete occlusion after blunt injury to the abdominal aorta and reviewed the cause, presentation, and management of this injury. Complete vessel occlusion arises from intimal injury. The most frequent mechanism is compression from a seat belt or steering wheel during a motor vehicle crash. Patients present with absent femoral and distal pulses in association with lower extremity neuropathy. Intervention commonly involves bypass grafting of the abdominal aorta. Complete occlusion after blunt trauma to the abdominal aorta is rare. Neurologic deficits most commonly arise from peripheral nerve ischemia. Reperfusion within 6 hours confers a greater chance of limb salvage and neurologic recovery.

Aorta-Iliac Bypass in Thoracoabdominal Aortic Aneurysm Repair in Young Chinese Patients.

PubMed

Duan, Yu-Yin; Ge, Yi-Peng; Zheng, Jun; Pan, Xu-Dong; Dong, Xiu-Hua; Ma, Wei-Guo; Cheng, Li-Jian; Zhu, Jun-Ming; Liu, Yong-Min; Sun, Li-Zhong

2016-04-01

Many surgical methods of thoracoabdominal aortic aneurysm repair (TAAAR) have been introduced over the past several decades, with varying degrees of success. We developed an aorta-iliac bypass technique to treat thoracoabdominal aortic aneurysm (TAAA) in young Chinese patients. The aim of this study is to evaluate the results of this technique intraoperatively and postoperatively. From June 2014 to March 2015, 28 patients underwent TAAAR using aorta-iliac bypass technique. A four-branched tetrafurcate graft was used. Two branches of the graft are sutured to bilateral common iliac arteries in an end-to-side fashion. The trunk of the graft was sutured to the proximal descending aorta in an end-to-end fashion. Then aorta-iliac bypass was established, and the lower extremities, viscera organ and spinal cord (SC) obtained perfusion from proximal descending aorta via the bypass graft. The thoracic and abdominal aorta were clamped in a staged fashion. The patent segmental arteries (SAs), and visceral arteries (coeliac trunk, superior mesenteric arteries, and renal arteries) were reattached sequentially. Evoked potential (EP) monitoring was adopted to assess the SC ischaemia throughout the procedure. The postoperative outcomes and follow-up results of this technique were evaluated. There was no in-hospital mortality. Complications included acute kidney dysfunction and pulmonary haemorrhage in one case (3.6%) each. The SAs were reattached in all cases. The EP wave disappeared after proximal descending aorta was clamped, and gradually recovered after the patent SAs reattached. The median follow-up after operation was eight months (range, 1-10 months). There was no delayed neurologic deficit or late death. Thoracoabdominal aortic aneurysm repair using aorta-iliac bypass may be a simple and safe choice for young Chinese patients with thoracoabdominal aortic aneurysms. Copyright © 2015 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Loss of pulse pressure amplification between the ascending and descending aorta in patients after an aortic arch repair.

PubMed

Murakami, Tomoaki; Shiraishi, Masahiro; Nawa, Tomohiro; Takeda, Atsuhito

2017-03-01

One of the most important problems in patients with an aortic coarctation after an aortic arch repair is future cardiovascular disease. We previously reported the enhancement of the aortic pressure wave reflection in patients and hypothesized that the enhancement was caused by a new pressure wave reflection generated from the repaired site. To prove the hypothesis, we analyzed the pressure waveform in the ascending and descending aorta and examined their pulse pressure (PP) amplification. Fifteen patients after an aortic arch repair without a recoarctation were enrolled. The ascending and descending aorta pressure waveforms were recorded by a pressure sensor mounted catheter. The pressures were compared with those of age-matched controls. The patient's age was 7.3 ± 2.7 years, and they underwent the aortic arch repair at 30.1 ± 29.0 days. The ascending aorta SBP (106.1 ± 12.7 mmHg) was higher than in the control patients (97.9 ± 14.3) (P = 0.015). The PP at the ascending aorta in the patients (41.3 ± 7.8) was wider than that in the controls (36.4 ± 5.0) (P = 0.010). There was no difference concerning the PP at the descending aorta between the patients (41.0 ± 7.7) and controls (40.5 ± 6.5). The difference in the PP between the descending and ascending aorta (PP at the descending aorta - PP at the ascending aorta) in the patients was -0.3 ± 1.7 and 5.1 ± 2.9 in the controls (P < 0.0001). The ascending aortic PP was augmented in the patients after the aortic arch repair. It could be one of the causes of future cardiovascular disease.

Transcriptional and phenotypic changes in aorta and aortic valve with aging and MnSOD deficiency in mice

PubMed Central

Roos, Carolyn M.; Hagler, Michael; Zhang, Bin; Oehler, Elise A.; Arghami, Arman

2013-01-01

The purpose of this study was to characterize changes in antioxidant and age-related gene expression in aorta and aortic valve with aging, and test the hypothesis that increased mitochondrial oxidative stress accelerates age-related endothelial and aortic valve dysfunction. Wild-type (MnSOD+/+) and manganese SOD heterozygous haploinsufficient (MnSOD+/−) mice were studied at 3 and 18 mo of age. In aorta from wild-type mice, antioxidant expression was preserved, although there were age-associated increases in Nox2 expression. Haploinsufficiency of MnSOD did not alter antioxidant expression in aorta, but increased expression of Nox2. When compared with that of aorta, age-associated reductions in antioxidant expression were larger in aortic valves from wild-type and MnSOD haploinsufficient mice, although Nox2 expression was unchanged. Similarly, sirtuin expression was relatively well-preserved in aorta from both genotypes, whereas expression of SIRT1, SIRT2, SIRT3, SIRT4, and SIRT6 were significantly reduced in the aortic valve. Expression of p16ink4a, a marker of cellular senescence, was profoundly increased in both aorta and aortic valve from MnSOD+/+ and MnSOD+/− mice. Functionally, we observed comparable age-associated reductions in endothelial function in aorta from both MnSOD+/+ and MnSOD+/− mice. Interestingly, inhibition of NAD(P)H oxidase with apocynin or gp91ds-tat improved endothelial function in MnSOD+/+ mice but significantly impaired endothelial function in MnSOD+/− mice at both ages. Aortic valve function was not impaired by aging or MnSOD haploinsufficiency. Changes in antioxidant and sirtuin gene expression with aging differ dramatically between aorta and aortic valve. Furthermore, although MnSOD does not result in overt cardiovascular dysfunction with aging, compensatory transcriptional responses to MnSOD deficiency appear to be tissue specific. PMID:23997094

Aortic elongation in aortic aneurysm and dissection: the Tübingen Aortic Pathoanatomy (TAIPAN) project.

PubMed

Krüger, Tobias; Sandoval Boburg, Rodrigo; Lescan, Mario; Oikonomou, Alexandre; Schneider, Wilke; Vöhringer, Luise; Lausberg, Henning; Bamberg, Fabian; Blumenstock, Gunnar; Schlensak, Christian

2018-01-24

To study the lengths and diameters of aortic segments in healthy and diseased aortas and to assess the role of aortic elongation in Type A aortic dissection (TAD) prediction. Ectasia and aneurysm were defined by ascending aorta diameters of 45-54 mm and ≥55 mm, respectively. Computed tomography angiography studies of 256 healthy, 102 ectasia, 38 aneurysm, 17 pre-TAD and 166 TAD aortas were analysed using curved multiplanar reformats. The study groups were structurally equal. The diameter of the ascending aorta was 35 mm in the control group and was larger (P < 0.001) in the pre-TAD (43 mm) and TAD (56 mm) groups. The length of the ascending aorta from the aortic annulus to the brachiocephalic trunk was 92 mm in the control group, 113 mm in the ectasia group, 120 mm in the aneurysm group and 111 mm and 118 mm in the pre-TAD and TAD groups (all P < 0.001 compared with the control group). An ascending aorta length of 120 mm was exceeded in 2% of the control group, 31% of the ectasia group, 50% of the aneurysm group, 24% of the pre-TAD group and 48% of the TAD group. The correlation between the diameter and the length of the ascending aorta was r = 0.752; therefore, both parameters must be examined separately. A score considering both parameters identified 23.5% of pre-TAD patients, significantly more than the diameter alone, and 31.4% of ectasia aortas were elongated. Patients with ectatic (45-54 mm diameter) and elongated (≥120 mm) ascending aortas represent a high-risk subpopulation for TAD. © The Author(s) 2018. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Sudden aortic death-proposal for a comprehensive diagnostic approach in forensic and in clinical pathology practice.

PubMed

de Boer, Hans H; Dedouit, Fabrice; Chappex, Nina; van der Wal, Allard C; Michaud, Katarzyna

2017-11-01

Aortic rupture or dissection as immediate cause of sudden death is encountered in forensic and clinical autopsy practice. Despite a common denominator of 'sudden aortic death' (SAD), we expect that in both settings the diagnostic workup, being either primarily legal or primarily disease related, differs substantially, which may affect the eventual diagnoses. We retrospectively reviewed case records of deceased persons who fitted a diagnosis of SAD in the continuous autopsy cohorts in a forensic (Suisse) and a clinical setting (The Netherlands). Clinical characteristics, data from post-mortem imaging, tissue blocks for histological analysis and results of ancillary studies were reviewed for its presence and outcome. SAD was found in 7.7% in the forensic versus 2.2% in the clinical autopsies. In the forensic setting, autopsy was always combined with post-mortem imaging, showing variable outcome on detection of aortic disruption and/or pericardial bleeding. Histology of aorta was performed in 12/35 cases, mostly in the natural deaths. In the clinical setting, histology of the aorta was available in all cases, but post-mortem imaging in none. In both settings, underlying aortic disease was mostly cystic medial degeneration, atherosclerosis or a combination of both, with occasional rare unexpected diagnosis. Also in both, a genetic cause of aortic dissection was revealed in a minority (three cases). Sudden aortic death (SAD) is more commonly encountered in a forensic than in a clinical setting. Major differences in the approach of SAD between these settings coincide with similarities in causes of death and underlying diseases. To ensure a correct diagnosis, we recommend that the investigation of SAD includes a study of the medical history, a full autopsy with histology of major organs including aorta, and storage of material for toxicological and genetic testing. Post-mortem radiological examination, useful for documentation and screening purposes, is feasible as non-invasive alternative when autopsy is not possible, but cannot substitute a full autopsy.

Ascending aorta dilatation in patients with bicuspid aortic valve stenosis: a prospective CMR study.

PubMed

Rossi, Alexia; van der Linde, Denise; Yap, Sing Chien; Lapinskas, Thomas; Kirschbaum, Sharon; Springeling, Tirza; Witsenburg, Maarten; Cuypers, Judith; Moelker, Adriaan; Krestin, Gabriel P; van Dijk, Arie; Johnson, Mark; van Geuns, Robert-Jan; Roos-Hesselink, Jolien W

2013-03-01

The aim of this study was to evaluate the natural progression of aortic dilatation and its association with aortic valve stenosis (AoS) in patients with bicuspid aortic valve (BAV). Prospective study of aorta dilatation in patients with BAV and AoS using cardiac magnetic resonance (CMR). Aortic root, ascending aorta, aortic peak velocity, left ventricular systolic and diastolic function and mass were assessed at baseline and at 3-year follow-up. Of the 33 enrolled patients, 5 needed surgery, while 28 patients (17 male; mean age: 31 ± 8 years) completed the study. Aortic diameters significantly increased at the aortic annulus, sinus of Valsalva and tubular ascending aorta levels (P < 0.050). The number of patients with dilated tubular ascending aortas increased from 32 % to 43 %. No significant increase in sino-tubular junction diameter was observed. Aortic peak velocity, ejection fraction and myocardial mass significantly increased while the early/late filling ratio significantly decreased at follow-up (P < 0.050). The progression rate of the ascending aorta diameter correlated weakly with the aortic peak velocity at baseline (R (2) = 0.16, P = 0.040). BAV patients with AoS showed a progressive increase of aortic diameters with maximal expression at the level of the tubular ascending aorta. The progression of aortic dilatation correlated weakly with the severity of AoS.

Feasibility of low contrast media volume in CT angiography of the aorta.

PubMed

Seehofnerová, Anna; Kok, Madeleine; Mihl, Casper; Douwes, Dave; Sailer, Anni; Nijssen, Estelle; de Haan, Michiel J W; Wildberger, Joachim E; Das, Marco

2015-01-01

Using smaller volumes of contrast media (CM) in CT angiography (CTA) is desirable in terms of cost reduction and prevention of contrast-induced nephropathy (CIN). The purpose was to evaluate the feasibility of low CM volume in CTA of the aorta. 77 patients referred for CTA of the aorta were scanned using a standard MDCT protocol at 100 kV. A bolus of 50 ml CM (Iopromide 300 mg Iodine/ml) at a flow rate of 6 ml/s was applied (Iodine delivery rate IDR = 1.8 g/s; Iodine load 15 g) followed by a saline bolus of 40 ml at the same flow rate. Scan delay was determined by the test bolus method. Subjective image quality was assessed and contrast enhancement was measured at 10 anatomical levels of the aorta. Diagnostic quality images were obtained for all patients, reaching a mean overall contrast enhancement of 324 ± 28 HU. Mean attenuation was 350 ± 60 HU at the thoracic aorta and 315 ± 83 HU at the abdominal aorta. A straightforward low volume CM protocol proved to be technically feasible and led to CTA examinations reaching diagnostic image quality of the aorta at 100 kV. Based on these findings, the use of a relatively small CM bolus can be incorporated into routine clinical imaging.

Catching a floating thrombus; a case report on the treatment of a large thrombus in the ascending aorta.

PubMed

de Maat, Gijs Eduard; Vigano, Giorgio; Mariani, Massimo Alessandro; Natour, Ehsan

2017-05-19

The ascending aorta is an uncommon site for non-infective thrombus. In non-aneurysmal and non-atherosclerotic vessels this condition becomes extremely rare, while it represents a source of potential cerebral and peripheral embolic events. Currently, there is no consensus in the guidelines on how to treat a free floating thrombus in ascending aorta, therefore we present our decision making process and therapeutic strategy. A healthy 48-year-old man was hospital admitted with acute abdominal pain. CT-scan showed a right renal embolism in presence of a defect in the distal ascending aorta suggestive for thrombus. After heart team discussion the patient was scheduled for surgery and successfully underwent an emergent thrombus removal. Also, owing to multiple aortic wall insertions, the ascending aorta was replaced. The patient's recovery was uneventful and histological examination showed no signs of connective tissue disorders of aortic wall while confirmed the thrombotic nature of the mass. We present a patient with a floating thrombus in the ascending aorta who underwent an ascending aorta replacement. While angio-CT scan led to a prompt diagnosis, intraoperative epi-aortic echocardiography allowed to define precise location of thrombus, minimizing operative risk. This case demonstrates that multi-disciplinary heart team discussion is essential to define a successful strategy, that surgical treatment is feasible with specific tools such as epi-aortic echocardiography.

Automatic segmentation of thoracic aorta segments in low-dose chest CT

NASA Astrophysics Data System (ADS)

Noothout, Julia M. H.; de Vos, Bob D.; Wolterink, Jelmer M.; Išgum, Ivana

2018-03-01

Morphological analysis and identification of pathologies in the aorta are important for cardiovascular diagnosis and risk assessment in patients. Manual annotation is time-consuming and cumbersome in CT scans acquired without contrast enhancement and with low radiation dose. Hence, we propose an automatic method to segment the ascending aorta, the aortic arch and the thoracic descending aorta in low-dose chest CT without contrast enhancement. Segmentation was performed using a dilated convolutional neural network (CNN), with a receptive field of 131 × 131 voxels, that classified voxels in axial, coronal and sagittal image slices. To obtain a final segmentation, the obtained probabilities of the three planes were averaged per class, and voxels were subsequently assigned to the class with the highest class probability. Two-fold cross-validation experiments were performed where ten scans were used to train the network and another ten to evaluate the performance. Dice coefficients of 0.83 +/- 0.07, 0.86 +/- 0.06 and 0.88 +/- 0.05, and Average Symmetrical Surface Distances (ASSDs) of 2.44 +/- 1.28, 1.56 +/- 0.68 and 1.87 +/- 1.30 mm were obtained for the ascending aorta, the aortic arch and the descending aorta, respectively. The results indicate that the proposed method could be used in large-scale studies analyzing the anatomical location of pathology and morphology of the thoracic aorta.

Impact of Age-Dependent Adventitia Inflammation on Structural Alteration of Abdominal Aorta in Hyperlipidemic Mice

PubMed Central

Sakamoto, Sumiharu; Tsuruda, Toshihiro; Hatakeyama, Kinta; Imamura, Takuroh; Asada, Yujiro; Kitamura, Kazuo

2014-01-01

Background The adventitia is suggested to contribute to vascular remodeling; however, the site-selective inflammatory responses in association with the development of atherosclerosis remain to be elucidated. Methods and Results Wild-type or apolipoprotein E knockout male C57BL/6J background mice were fed standard chow for 16, 32, and 52 weeks, and the morphology of the aortic arch, descending aorta, and abdominal aorta was compared. Atheromatous plaque formation progressed with age, particularly in the aortic arch and abdominal aorta but not in the descending aorta. In addition, we found that the numbers of macrophages, T-lymphocytes, and microvessels, assessed by anti-F4/80, CD3, and CD31 antibodies, were higher in the adventitia of the abdominal aorta at 52 weeks. These numbers were positively correlated with plaque formation, but negatively correlated with elastin content, resulting in the enlargement of the total vessel area. In aortic tissues, interleukin-6 levels increased in the atheromatous plaque with age, whereas the level of regulated on activation, normal T cell expressed and secreted (RANTES) increased with age, and compared with other sites, it was particularly distributed in inflammatory cells in the adventitia of the abdominal aorta. Conclusion This study suggests that adventitial inflammation contributes to the age-dependent structural alterations, and that the activation/inactivation of cytokines/chemokines is involved in the process. PMID:25153991

Superior Mesenteric Artery Syndrome Improved by Enteral Nutritional Therapy according to the Controlling Nutritional Status Score.

PubMed

Takehara, Kazuhiro; Sakamoto, Kazuhiro; Takahashi, Rina; Kawai, Masaya; Kawano, Shingo; Munakata, Shinya; Sugimoto, Kiichi; Takahashi, Makoto; Kojima, Yutaka; Fukunaga, Tetsu; Kajiyama, Yoshiaki; Kawasaki, Seiji

2017-01-01

Superior mesenteric artery syndrome (SMAS) is a relatively rare disease that involves bowel obstruction symptoms, such as vomiting and gastric distension, owing to the compression of the third portion of the duodenum from the front by the superior mesenteric artery (SMA) and from the rear by the abdominal aorta and the spine. SMAS is diagnosed on the basis of an upper gastrointestinal examination series indicating the obstruction of the third portion of the duodenum or a computed tomography scan indicating the narrowing of the branch angle between the aorta and the SMA (i.e., the aorta-SMA angle). Here, we report the case of a 78-year-old woman diagnosed with SMAS after a laparoscopic right hemicolectomy for cecal cancer, whose condition was improved by enteral nutritional therapy. We used her controlling nutritional status (CONUT) score as a nutrition assessment and noted the changes in the aorta-SMA angle over the course of the disease. This patient appeared to develop SMAS, on the basis of a worsened CONUT score and a decreased aorta-SMA angle, owing to the inflammation resulting from the intraoperative dissection of the tissues around the SMA and prolonged postoperative fasting. After the initiation of enteral nutritional therapy, the patient exhibited body weight gain and an improved aorta-SMA angle and CONUT score. Hence, assessment of the aorta-SMA angle and CONUT score is an important preoperative consideration.

Magnolol attenuates VCAM-1 expression in vitro in TNF-α-treated human aortic endothelial cells and in vivo in the aorta of cholesterol-fed rabbits

PubMed Central

Chen, Yung-Hsiang; Lin, Shing-Jong; Chen, Jaw-Wen; Ku, Hung-Hai; Chen, Yuh-Lien

2002-01-01

In a previous study, we showed that magnolol, a potent antioxidant derived from a Chinese herb, attenuates monocyte chemotactic protein-1 (MCP-1) expression and intimal hyperplasia in the balloon-injured aorta of cholesterol-fed rabbits. Expression of cell adhesion molecules by the arterial endothelium and the attachment of leukocytes to the endothelium may play a major role in atherosclerosis. In the present study, the effects of magnolol on the expression of endothelial-leukocyte adhesion molecules and the activation of nuclear factor kappa B (NF-κB) in tumour necrosis factor-α (TNF-α)-treated human aortic endothelial cells (HAECs) were investigated.Pretreatment of HAECs with magnolol (5 μM) significantly suppressed the TNF-α-induced expression of vascular cell adhesion molecule-1 (VCAM-1) (64.8±1.9%), but had no effect on the expression of intercellular cell adhesion molecule-1 and endothelial cell selectin.Magnolol (5 and 10 μM) significantly reduced the binding of the human monocytic cell line, U937, to TNF-α-stimulated HAECs (58.4 and 56.4% inhibition, respectively). Gel shift assays using the 32P-labelled NF-κB consensus sequence as probe showed that magnolol pretreatment reduced the density of the shifted bands seen after TNF-α-induced activation. Immunoblot analysis and immunofluorescence staining of nuclear extracts demonstrated a 58% reduction in the amount of NF-κB p65 in the nuclei in magnolol-treated HAECs. Magnolol also attenuated intracellular H2O2 generation in both control and TNF-α treated HAECs.Furthermore, in vivo, magnolol attenuates the intimal thickening and TNF-α and VCAM-1 protein expression seen in the thoracic aortas of cholesterol-fed rabbits.Taken together, these data demonstrate that magnolol inhibits TNF-α-induced nuclear translocation of NF-κB p65 and thereby suppresses expression of VCAM-1, resulting in reduced adhesion of leukocytes. These results suggest that magnolol has anti-inflammatory properties and may play important roles in the prevention of atherosclerosis and inflammatory responses in vivo. PMID:11786478

Differential vasoconstrictor activity of human urotensin-II in vascular tissue isolated from the rat, mouse, dog, pig, marmoset and cynomolgus monkey

PubMed Central

Douglas, Stephen A; Sulpizio, Anthony C; Piercy, Valerie; Sarau, Henry M; Ames, Robert S; Aiyar, Nambi V; Ohlstein, Eliot H; Willette, Robert N

2000-01-01

Urotensin-II (U-II) and its G-protein-coupled receptor, GPR14, are expressed within mammalian cardiac and peripheral vascular tissue and, as such, may regulate mammalian cardiovascular function. The present study details the vasoconstrictor profile of this cyclic undecapeptide in different vascular tissues isolated from a diverse range of mammalian species (rats, mice, dogs, pigs, marmosets and cynomolgus monkeys). The vasoconstrictor activity of human U-II was dependent upon the anatomical origin of the vessel studied and the species from which it was isolated. In the rat, constrictor responses were most pronounced in thoracic aortae and carotid arteries: −log[EC50]s 9.09±0.19 and 8.84±0.21, Rmaxs 143±21 and 67±26% 60 mM KCl, respectively (compared, for example, to −log[EC50] 7.90±0.11 and Rmax 142±12% 60 mM KCl for endothelin-1 [ET-1] in thoracic aortae). Responses were, however, absent in mice aortae (−log[EC50] <6.50). These findings were further contrasted by the observation that U-II was a ‘coronary-selective' spasmogen in the dog (−log[EC50] 9.46±0.11, Rmax 109±23% 60 mM KCl in LCX coronary artery), yet exhibited a broad spectrum of vasoconstrictor activity in arterial tissue from Old World monkeys (−log[EC50]s range from 8.96±0.15 to 9.92±0.13, Rmaxs from 43±16 to 527±135% 60 mM KCl). Interestingly, significant differences in reproducibility and vasoconstrictor efficacy were seen in tissue from pigs and New World primates (vessels which responded to noradrenaline, phenylephrine, KCl or ET-1 consistently). Thus, human U-II is a potent, efficacious vasoconstrictor of a variety of mammalian vascular tissues. Although significant species/anatomical variations exist, the data support the hypothesis that U-II influences the physiological regulation of mammalian cardiovascular function. PMID:11090097

77 FR 68788 - Neurological Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-16

... diverting cardiac output to the cerebral vasculature via partial occlusion of the descending aorta... inflation of the individual balloons. The device is placed in the descending aorta. On March 30, 2005, a... the descending aorta (K090970). CoAxia has submitted a de novo application for the NeuroFlo for the...

78 FR 36702 - Cardiovascular Devices; Reclassification of Intra-Aortic Balloon and Control Systems (IABP) for...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-19

... the femoral artery and resides in the descending aorta. Conventional timing sets inflation of the... pressure in the aorta. The deflation of the balloon takes place at the onset of systole during the... pressure in the aorta and this decrease in pressure assists the left ventricle by reducing the pressure...

Spontaneous hemothorax caused by ruptured multiple mycotic aortic aneurysms: a case report and literature review.

PubMed

Li, Po-Sung; Tsai, Chung-Lin; Hu, Sung-Yuan; Lin, Tzu-Chieh; Chang, Yao-Tien

2017-12-02

Mycotic aortic aneurysm (MAA) is a rare clinical entity with an incidence of 1-3%, but it is a life-threatening infection of aorta characterized by dilatation of aorta with false lumen. Multiple MAAs have been reported rarely with an incidence of 0.03% and associated with a high mortality rate of 80% if ruptured. A hypertensive and diabetic 78-year-old man visited our emergency department complaining intermittent dull and tingled pain over the left flank region for 1 week. Chest X-ray showed left pleural effusion and hemothorax was confirmed by thoracocentesis. Computed tomography (CT) of chest demonstrated multiple thoracic aortic aneurysms and the pathological findings disclosed the diagnosis of multiple MAAs. He was discharged under an uneventful condition post-surgical aortic repair with adequate intravenous antibiotics for 4 weeks. CT scan may make a definite diagnosis of multiple MAAs and management with surgical debridement, aortic repair and full-course antibiotics for Gram-positive coccus and/or Gram-negative bacillus is recommended.

Loss of Anticontractile Effect of Perivascular Adipose Tissue on Pregnant Rats: A Potential Role of Tumor Necrosis Factor-α.

PubMed

Al-Jarallah, Aishah; Oriowo, Mabayoje A

2016-02-01

The present investigation examined the effect of pregnancy on the anticontractile effect of perivascular adipose tissue (PVAT) on the rat. Ring segments of the aorta, with and without PVAT, were set up in organ baths for isometric tension recording. In both groups, concentration-response curves to 5-hydroxytryptamine (5-HT) were displaced to the right with a reduction of the maximum response in aorta segments with PVAT. The anticontractile effect of PVAT was attenuated on segments from pregnant rats. 4-Aminopyridine (4-AP), an inhibitor of voltage-gated potassium (Kv) channels, enhanced 5-HT-induced contractions of aorta segments from pregnant and nonpregnant rats only when PVAT was attached. There was no difference in the effect of 4-aminopyridine on 5-HT-induced contractions of aorta segments with PVAT from pregnant and nonpregnant rats. There was also no significant difference in the expression of Kv7.4 channels in aorta segments (with PVAT) between pregnant and nonpregnant rats. Tumor necrosis factor-α (TNF-α) was detected in PVAT from pregnant and nonpregnant rats. The level of TNF-α was significantly greater in PVAT from pregnant rats. Treatment of pregnant rats with pentoxyphyline significantly reduced the level of TNF-α in the PVAT and restored the anticontractile effect of PVAT on aorta segments from pregnant rats. Finally, TNF-α (10 ng/mL) potentiated 5-HT-induced contractions of PVAT-containing pregnant rat aorta. These results would suggest that the loss of anticontractile effect of PVAT in pregnant rat aorta could be due to enhanced production of TNF-α in the PVAT in these rats.

Ascending aortic curvature as an independent risk factor for type A dissection, and ascending aortic aneurysm formation: a mathematical model.

PubMed

Poullis, Michael P; Warwick, Richard; Oo, Aung; Poole, Robert J

2008-06-01

To develop a mathematical model to demonstrate that ascending aortic curvature is an independent risk factor for type A dissections, in addition to hypertension, bicuspid aortic valve, aneurysm of ascending aorta, and intrinsic aortic tissue abnormalities, like Marfan's syndrome. A steady state one-dimensional flow analysis was performed, utilising Newton's third law of motion. Five different clinical scenarios were evaluated: (1) effect of aortic curvature; (2) effect of beta-blockers, (3) effect of patient size, (4) forces on a Marfan's aorta, and (5) site of entry flap in aortic dissection. Aortic curvature increases the forces exerted on the ascending aorta by a factor of over 10-fold. Aortic curvature can cause patients with a systolic blood pressure of 8 0mmHg to have greater forces exerted on their aorta despite smaller diameters and lower cardiac outputs, than patients with systolic blood pressures of 120 mmHg. In normal diameter aortas, beta-blockers have minimal effect compared with aortic curvature. Aortic curvature may help to explain why normal diameter aortas can dissect, and also that the point of the entry tear may be potentially predictable. Aortic curvature has major effects on the forces exerted on the aorta in patients with Marfan's syndrome. Aortic curvature is relatively more important that aortic diameter, blood pressure, cardiac output, beta-blocker use, and patient size with regard to the force acting on the aortic wall. This may explain why some patients with normal diameter ascending aortas with or without Marfan's syndrome develop type A dissections and aneurysms. Aortic curvature may also help to explain the site of entry tear in acute type A dissection. Further clinical study is needed to validate this study's finding.

Investigation of hemodynamics in the development of dissecting aneurysm within patient-specific dissecting aneurismal aortas using computational fluid dynamics (CFD) simulations.

PubMed

Tse, Kwong Ming; Chiu, Peixuan; Lee, Heow Pueh; Ho, Pei

2011-03-15

Aortic dissecting aneurysm is one of the most catastrophic cardiovascular emergencies that carries high mortality. It was pointed out from clinical observations that the aneurysm development is likely to be related to the hemodynamics condition of the dissected aorta. In order to gain more insight on the formation and progression of dissecting aneurysm, hemodynamic parameters including flow pattern, velocity distribution, aortic wall pressure and shear stress, which are difficult to measure in vivo, are evaluated using numerical simulations. Pulsatile blood flow in patient-specific dissecting aneurismal aortas before and after the formation of lumenal aneurysm (pre-aneurysm and post-aneurysm) is investigated by computational fluid dynamics (CFD) simulations. Realistic time-dependent boundary conditions are prescribed at various arteries of the complete aorta models. This study suggests the helical development of false lumen around true lumen may be related to the helical nature of hemodynamic flow in aorta. Narrowing of the aorta is responsible for the massive recirculation in the poststenosis region in the lumenal aneurysm development. High pressure difference of 0.21 kPa between true and false lumens in the pre-aneurismal aorta infers the possible lumenal aneurysm site in the descending aorta. It is also found that relatively high time-averaged wall shear stress (in the range of 4-8 kPa) may be associated with tear initiation and propagation. CFD modeling assists in medical planning by providing blood flow patterns, wall pressure and wall shear stress. This helps to understand various phenomena in the development of dissecting aneurysm. Copyright © 2011 Elsevier Ltd. All rights reserved.

Collagen-induced arthritis increases inducible nitric oxide synthase not only in aorta but also in the cardiac and renal microcirculation of mice.

PubMed

Palma Zochio Tozzato, G; Taipeiro, E F; Spadella, M A; Marabini Filho, P; de Assis, M R; Carlos, C P; Girol, A P; Chies, A B

2016-03-01

Rheumatoid arthritis (RA) may promote endothelial dysfunction. This phenomenon requires further investigation, especially in collagen-induced arthritis (CIA), as it is considered the experimental model most similar to RA. The objectives of this study were to identify CIA-induced changes in noradrenaline (NE) and acetylcholine (ACh) responses in mice aortas that may suggest endothelial dysfunction in these animals. Moreover, we characterize CIA-induced modifications in inducible nitric oxide synthase (iNOS) expression in the aortas and cardiac and renal tissues taken from these mice that may be related to possible endothelial dysfunction. Male DBA/1J mice were immunized with 100 μg of emulsified bovine collagen type II (CII) plus complete Freund's adjuvant. Twenty-one days later, these animals received a boost of an additional 100 μg plus incomplete Freund's adjuvant. Fifteen days after the onset of the disease, aortic rings from CIA and control mice were challenged with NE and ACh in an organ bath. In these animals, iNOS was detected through immunohistochemical analysis of aorta, heart and kidneys. Plasma nitrite concentration was determined using the Griess reaction. CIA did not change NE or ACh responses in mice aorta but apparently increased the iNOS expression not only in aorta, but also in cardiac and renal microcirculation. In parallel, CIA reduced nitrite plasma concentration. In mice, CIA appears to increase the presence of iNOS in aorta, as well as in heart and in kidney microcirculation. This iNOS increase occurs apparently in parallel to a reduction of the bioavailability of NO. This phenomenon does not appear to change NE or ACh responses in aorta. © 2015 British Society for Immunology, Clinical and Experimental Immunology.

Pulmonary arterial hypertension in children: diagnosis using ratio of main pulmonary artery to ascending aorta diameter as determined by multi-detector computed tomography.

PubMed

Caro-Domínguez, Pablo; Compton, Gregory; Humpl, Tilman; Manson, David E

2016-09-01

The ratio of the transverse diameter of the main pulmonary artery (MPA) to ascending aorta as determined at multi-detector CT is a tool that can be used to assess the pulmonary arterial size in cases of pulmonary arterial hypertension in children. To establish a ratio of MPA to ascending aorta diameter using multi-detector CT imaging suggestive of pulmonary arterial hypertension in children. We hypothesize that a defined ratio of MPA to ascending aorta is identifiable on multi-detector CT and that higher ratios can be used to reliably diagnose the presence of pulmonary arterial hypertension in children. We calculated the multi-detector CT ratio of MPA to ascending aorta diameter in 44 children with documented pulmonary arterial hypertension by right heart catheterization and in 44 age- and gender-matched control children with no predisposing factors for pulmonary arterial hypertension. We compared this multi-detector-CT-determined ratio with the MPA pressure in the study group, as well as with the ratio of MPA to ascending aorta in the control group. A threshold ratio value was calculated to accurately identify children with pulmonary arterial hypertension. Children with documented primary pulmonary arterial hypertension have a significantly higher ratio of MPA to ascending aorta (1.46) than children without pulmonary arterial hypertension (1.11). A ratio of 1.3 carries a positive likelihood of 34 and a positive predictive value of 97% for the diagnosis of pulmonary arterial hypertension. The pulmonary arteries were larger in children with pulmonary arterial hypertension than in a control group of normal children. A CT-measured ratio of MPA to ascending aorta of 1.3 should raise the suspicion of pulmonary arterial hypertension in children.

Effects of nesfatin-1 on atrial contractility and thoracic aorta reactivity in male rats.

PubMed

Barutcigil, Ayşe; Tasatargil, Arda

2017-10-13

This study aimed to examine the effects of nesfatin-1 on thoracic aorta vasoreactivity and to investigate the inotropic and chronotropic effects of nesfatin-1 on the spontaneous contractions of the isolated rat atria. Isolated right atria and thoracic aorta were used in organ baths. The reactivity of the thoracic aorta was evaluated by potassium chloride (KCl), phenylephrine (Phe), acetylcholine (ACh), and sodium nitroprusside (SNP). The effects of nesfatin-1 on the spontaneous contractions of the rat atria were also examined. Nesfatin-1 (0.1-100 ng/ml) produced a concentration-dependent relaxation response in rat thoracic aorta. The relaxant responses to nesfatin-1 were inhibited by the removal of endothelium, NO synthase blocker N-nitro-L-arginine methyl ester (L-NAME, 10 -4  M), and soluble guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, 10 -5  M). Nesfatin-1 (10 ng/ml, 30 min) increased the relaxation responses to either ACh or SNP, and the contractile response to both Phe and KCl did not significantly change in the arteries that were incubated with nesfatin-1 compared with the controls. The thoracic aorta contractions induced by the stepwise addition of Ca 2+ to a high KCl solution with no Ca 2+ were not significantly changed by nesfatin-1. Under calcium-free conditions, the contractions of the thoracic aorta rings incubated with nesfatin-1 in response to Phe were not significantly lower than those of the rings from the control rats. Nesfatin-1 showed positive inotropic and chronotropic effects on rat atria. Nesfatin-1 significantly changed the vascular responsiveness in rat thoracic aorta and produced positive inotropic and chronotropic effects on rat atria.

Dynamics of the aortic arch submitted to a shock loading: Parametric study with fluid-structure models.

PubMed

El Baroudi, A; Razafimahery, F; Rakotomanana, L

2012-01-01

This work aims to present some fluid-structure models for analyzing the dynamics of the aorta during a brusque loading. Indeed, various lesions may appear at the aortic arch during car crash or other accident such as brusque falling. Aortic stresses evolution are simulated during the shock at the cross section and along the aorta. One hot question was that if a brusque deceleration can generate tissue tearing, or a shock is necessary to provoke such a damage. Different constitutive laws of blood are then tested whereas the aorta is assumed linear and elastic. The overall shock model is inspired from an experimental jig. We show that the viscosity has strong influence on the stress and parietal moments and forces. The nonlinear viscosity has no significant additional effects for healthy aorta, but modifies the stress and parietal loadings for the stenotic aorta.

Atresia of the Descending Aorta in a Young Woman Requiring Bypass Graft.

PubMed

Dsc, Adcasdc Sadfasdf; Mashhood, Ammarah; Ali, Taimur Asif; Fatimi, Saulat Hasnain

2016-11-01

Congenital aortic atresia is a malformation accounting for 4 - 6% of all congenital heart diseases in children. Left ventricular outflow obstruction due to atresia is common at the aortic valve but rarely has atresia been identified in the descending aorta. We report the case of a 25-year woman who was evaluated for headache and uncontrolled hypertension. CTscan chest showed a short atretic segment in the descending aorta at the isthmus, distal to the takeoff of the subclavian artery. She underwent surgery; a 22 mm Dacron graft was taken and jump graft was placed between the arch of the aorta and the descending aorta, using partial occlusion clamps. Patient tolerated the procedure well and was discharged on ACE Inhibitors and beta blockers, which were then weaned off over a period of one year. She remained stable and had no further complaints.

Acrolein generation stimulates hypercontraction in isolated human blood vessels

PubMed Central

Conklin, D.J.; Bhatnagar, A.; Cowley, H.R.; Johnson, G.H.; Wiechmann, R.J.; Sayre, L.M.; Trent, M.B.; Boor, P.J.

2012-01-01

Increased risk of vasospasm, a spontaneous hyperconstriction, is associated with atherosclerosis, cigarette smoking, and hypertension—all conditions involving oxidative stress, lipid peroxidation, and inflammation. To test the role of the lipid peroxidation- and inflammation-derived aldehyde, acrolein, in human vasospasm, we developed an ex vivo model using human coronary artery bypass graft (CABG) blood vessels and a demonstrated acrolein precursor, allylamine. Allylamine induces hypercontraction in isolated rat coronary artery in a semicarbazide-sensitive amine oxidase activity (SSAO) dependent manner. Isolated human CABG blood vessels (internal mammary artery, radial artery, saphenous vein) were used to determine: (1) vessel responses and sensitivity to acrolein, allylamine, and H2O2 exposure (1 μM–1 mM), (2) SSAO dependence of allylamine-induced effects using SSAO inhibitors (semicarbazide, 1 mM; MDL 72274-E, active isomer; MDL 72274-Z, inactive isomer; 100 μM), (3) the vasoactive effects of two other SSAO amine substrates, benzylamine and methylamine, and (4) the contribution of extracellular Ca2+ to hypercontraction. Acrolein or allylamine but not H2O2, benzylamine, or methylamine stimulated spontaneous and pharmacologically intractable hypercontraction in CABG blood vessels that was similar to clinical vasospasm. Allylamine-induced hypercontraction and blood vessel SSAO activity were abolished by pretreatment with semicarbazide or MDL 72274-E but not by MDL 72274-Z. Allylamine-induced hypercontraction also was significantly attenuated in Ca2+-free buffer. In isolated aorta of spontaneously hypertensive rat, allylamine-induced an SSAO-dependent contraction and enhanced norepinephrine sensitivity but not in Sprague–Dawley rat aorta. We conclude that acrolein generation in the blood vessel wall increases human susceptibility to vasospasm, an event that is enhanced in hypertension. PMID:17095030

Combined open proximal and stent-graft distal repair for distal arch aneurysms: an alternative to total debranching.

PubMed

Zierer, Andreas; Sanchez, Luis A; Moon, Marc R

2009-07-01

We present herein a novel, combined, simultaneous open proximal and stent-graft distal repair for complex distal aortic arch aneurysms involving the descending aorta. In the first surgical step, the transverse arch is opened during selective antegrade cerebral perfusion, and a Dacron graft (DuPont, Wilmington, DE) is positioned down the descending aorta in an elephant trunk-like fashion with its proximal free margin sutured circumferentially to the aorta just distal to the left subclavian or left common carotid artery. With the graft serving as the new proximal landing zone, subsequent endovascular repair is performed antegrade during rewarming through the ascending aorta.

Tensile characterisation of the aorta across quasi-static to blast loading strain rates

NASA Astrophysics Data System (ADS)

Magnus, Danyal; Proud, William; Haller, Antoine; Jouffroy, Apolline

2017-06-01

The dynamic tensile failure mechanisms of the aorta during Traumatic Aortic Injury (TAI) are poorly understood. In automotive incidents, where the aorta may be under strains of the order of 100/s, TAI is the second largest cause of mortality. In these studies, the proximal descending aorta is the most common site where rupture is observed. In particular, the transverse direction is most commonly affected due to the circumferential orientation of elastin, and hence the literature generally concentrates upon axial samples. This project extends these dynamic studies to the blast loading regime where strain-rates are of the order of 1000/s. A campaign of uniaxial tensile experiments are conducted at quasi-static, intermediate (drop-weight) and high (tensile Split-Hopkinson Pressure Bar) strain rates. In each case, murine and porcine aorta models are considered and the extent of damage assessed post-loading using histology. Experimental data will be compared against current viscoelastic models of the aorta under axial stress. Their applicability across strain rates will be discussed. Using a multi-disciplinary approach, the conditions applied to the samples replicate in vivo conditions, employing a blood simulant-filled tubular specimen surrounded by a physiological solution.

Differences in the Thoracic Aorta by Region and Sex in a Murine Model of Marfan Syndrome.

PubMed

Jiménez-Altayó, Francesc; Siegert, Anna-Maria; Bonorino, Fabio; Meirelles, Thayna; Barberà, Laura; Dantas, Ana P; Vila, Elisabet; Egea, Gustavo

2017-01-01

Marfan syndrome (MFS) is a hereditary disorder of the connective tissue that causes life-threatening aortic aneurysm, which initiates at the aortic root and can progress into the ascending portion. However, analysis of ascending aorta reactivity in animal models of MFS has remained elusive. Epidemiologic evidence suggests that although MFS is equally prevalent in men and women, men are at a higher risk of aortic complications than non-pregnant women. Nevertheless, there is no experimental evidence to support this hypothesis. The aim of this study was to explore whether there are regional and sex differences in the thoracic aorta function of mice heterozygous for the fibrillin 1 ( Fbn1 ) allele encoding a missense mutation ( Fbn1 C1039G/+ ), the most common class of mutation in MFS. Ascending and descending thoracic aorta reactivity was evaluated by wire myography. Ascending aorta mRNA and protein levels, and elastic fiber integrity were assessed by qRT-PCR, Western blotting, and Verhoeff-Van Gieson histological staining, respectively. MFS differently altered reactivity in the ascending and descending thoracic aorta by either increasing or decreasing phenylephrine contractions, respectively. When mice were separated by sex, contractions to phenylephrine increased progressively from 3 to 6 months of age in MFS ascending aortas of males, whereas contractions in females were unchanged. Endothelium-dependent relaxation was unaltered in the MFS ascending aorta of either sex; an effect related to augmented endothelium-dependent hyperpolarization-type dilations. In MFS males, the non-selective cyclooxygenase (COX) inhibitor indomethacin prevented the MFS-induced enhancement of phenylephrine contractions linked to increased COX-2 expression. In MFS mice of both sexes, the non-selective nitric oxide synthase inhibitor L-NAME revealed negative feedback of nitric oxide on phenylephrine contractions, which was associated with upregulation of eNOS in females. Finally, MFS ascending aortas showed a greater number of elastic fiber breaks than the wild-types, and males exhibited more breaks than females. These results show regional and sex differences in Fbn1 C1039G/+ mice thoracic aorta contractility and aortic media injuries. The presence of more pronounced aortic alterations in male mice provides experimental evidence to support that male MFS patients are at increased risk of suffering aortic complications.

Differences in the Thoracic Aorta by Region and Sex in a Murine Model of Marfan Syndrome

PubMed Central

Jiménez-Altayó, Francesc; Siegert, Anna-Maria; Bonorino, Fabio; Meirelles, Thayna; Barberà, Laura; Dantas, Ana P.; Vila, Elisabet; Egea, Gustavo

2017-01-01

Marfan syndrome (MFS) is a hereditary disorder of the connective tissue that causes life-threatening aortic aneurysm, which initiates at the aortic root and can progress into the ascending portion. However, analysis of ascending aorta reactivity in animal models of MFS has remained elusive. Epidemiologic evidence suggests that although MFS is equally prevalent in men and women, men are at a higher risk of aortic complications than non-pregnant women. Nevertheless, there is no experimental evidence to support this hypothesis. The aim of this study was to explore whether there are regional and sex differences in the thoracic aorta function of mice heterozygous for the fibrillin 1 (Fbn1) allele encoding a missense mutation (Fbn1C1039G/+), the most common class of mutation in MFS. Ascending and descending thoracic aorta reactivity was evaluated by wire myography. Ascending aorta mRNA and protein levels, and elastic fiber integrity were assessed by qRT-PCR, Western blotting, and Verhoeff-Van Gieson histological staining, respectively. MFS differently altered reactivity in the ascending and descending thoracic aorta by either increasing or decreasing phenylephrine contractions, respectively. When mice were separated by sex, contractions to phenylephrine increased progressively from 3 to 6 months of age in MFS ascending aortas of males, whereas contractions in females were unchanged. Endothelium-dependent relaxation was unaltered in the MFS ascending aorta of either sex; an effect related to augmented endothelium-dependent hyperpolarization-type dilations. In MFS males, the non-selective cyclooxygenase (COX) inhibitor indomethacin prevented the MFS-induced enhancement of phenylephrine contractions linked to increased COX-2 expression. In MFS mice of both sexes, the non-selective nitric oxide synthase inhibitor L-NAME revealed negative feedback of nitric oxide on phenylephrine contractions, which was associated with upregulation of eNOS in females. Finally, MFS ascending aortas showed a greater number of elastic fiber breaks than the wild-types, and males exhibited more breaks than females. These results show regional and sex differences in Fbn1C1039G/+ mice thoracic aorta contractility and aortic media injuries. The presence of more pronounced aortic alterations in male mice provides experimental evidence to support that male MFS patients are at increased risk of suffering aortic complications. PMID:29187826

Feasibility of low contrast media volume in CT angiography of the aorta

PubMed Central

Seehofnerová, Anna; Kok, Madeleine; Mihl, Casper; Douwes, Dave; Sailer, Anni; Nijssen, Estelle; de Haan, Michiel J.W.; Wildberger, Joachim E.; Das, Marco

2015-01-01

Objectives Using smaller volumes of contrast media (CM) in CT angiography (CTA) is desirable in terms of cost reduction and prevention of contrast-induced nephropathy (CIN). The purpose was to evaluate the feasibility of low CM volume in CTA of the aorta. Methods 77 patients referred for CTA of the aorta were scanned using a standard MDCT protocol at 100 kV. A bolus of 50 ml CM (Iopromide 300 mg Iodine/ml) at a flow rate of 6 ml/s was applied (Iodine delivery rate IDR = 1.8 g/s; Iodine load 15 g) followed by a saline bolus of 40 ml at the same flow rate. Scan delay was determined by the test bolus method. Subjective image quality was assessed and contrast enhancement was measured at 10 anatomical levels of the aorta. Results Diagnostic quality images were obtained for all patients, reaching a mean overall contrast enhancement of 324 ± 28 HU. Mean attenuation was 350 ± 60 HU at the thoracic aorta and 315 ± 83 HU at the abdominal aorta. Conclusions A straightforward low volume CM protocol proved to be technically feasible and led to CTA examinations reaching diagnostic image quality of the aorta at 100 kV. Based on these findings, the use of a relatively small CM bolus can be incorporated into routine clinical imaging. PMID:26937437

In vitro investigation of a novel elastic vascular prosthesis for valve-sparing aortic root and ascending aorta replacement.

PubMed

Scharfschwerdt, Michael; Leonhard, Moritz; Lehmann, Judith; Richardt, Doreen; Goldmann, Helmut; Sievers, Hans-Hinrich

2016-05-01

Prosthetic replacement of the thoracic aorta with common Dacron prostheses impairs the aortic 'windkessel' and, in valve-sparing procedures, also aortic valve function. Elastic graft material may overcome these deficiencies. Fresh porcine aortas including the root were set up in a mock circulation before and after replacement of the ascending part with a novel vascular prosthesis providing elastic behaviours. In a first series (n = 14), haemodynamics and leaflet motions of the aortic valve were investigated and also cyclic changes of aortic dimensions at different levels of the root. In a second series (n = 7), intravascular pressure and dimensions of the proximal descending aorta were measured and the corresponding wall tension was calculated. Haemodynamics of the aortic valve remain comparable after replacement. Though the novel prosthesis does not feature such high distensibility as the native aorta, the dynamic of the root was significantly increased compared with common Dacron prostheses at the commissural level, preserving 'windkessel' function. Thus, wall tension of the residual aorta remained unchanged; nevertheless, maximum pressure-time differential dp/dt increased by 13%. The use of the novel elastic prosthesis for replacement of the ascending aorta seems to be beneficial, especially with regard to the preservation of the aortic windkessel. Further studies will be needed to clarify long-term utilization of the material in vivo. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Single-Cell RNA-Seq Reveals the Transcriptional Landscape and Heterogeneity of Aortic Macrophages in Murine Atherosclerosis.

PubMed

Cochain, Clément; Vafadarnejad, Ehsan; Arampatzi, Panagiota; Jaroslav, Pelisek; Winkels, Holger; Ley, Klaus; Wolf, Dennis; Saliba, Antoine-Emmanuel; Zernecke, Alma

2018-03-15

Rationale: It is assumed that atherosclerotic arteries contain several macrophage subsets endowed with specific functions. The precise identity of these subsets is poorly characterized as they ha ve been defined by the expression of a restricted number of markers. Objective: We have applied single-cell RNA-seq as an unbiased profiling strategy to interrogate and classify aortic macrophage heterogeneity at the single-cell level in atherosclerosis. Methods and Results: We performed single-cell RNA sequencing of total aortic CD45 + cells extracted from the non-diseased (chow fed) and atherosclerotic (11 weeks of high fat diet) aorta of Ldlr -/- mice. Unsupervised clustering singled out 13 distinct aortic cell clusters. Among the myeloid cell populations, Resident-like macrophages with a gene expression profile similar to aortic resident macrophages were found in healthy and diseased aortae, whereas monocytes, monocyte-derived dendritic cells (MoDC), and two populations of macrophages were almost exclusively detectable in atherosclerotic aortae, comprising Inflammatory macrophages showing enrichment in I l1b , and previously undescribed TREM2 hi macrophages. Differential gene expression and gene ontology enrichment analyses revealed specific gene expression patterns distinguishing these three macrophage subsets and MoDC, and uncovered putative functions of each cell type. Notably, TREM2 hi macrophages appeared to be endowed with specialized functions in lipid metabolism and catabolism, and presented a gene expression signature reminiscent of osteoclasts, suggesting a role in lesion calcification. TREM2 expression was moreover detected in human lesional macrophages. Importantly, these macrophage populations were present also in advanced atherosclerosis and in Apoe -/- aortae, indicating relevance of our findings in different stages of atherosclerosis and mouse models. Conclusions: These data unprecedentedly uncovered the transcriptional landscape and phenotypic heterogeneity of aortic macrophages and MoDCs in atherosclerotic and identified previously unrecognized macrophage populations and their gene expression signature, suggesting specialized functions. Our findings will open up novel opportunities to explore distinct myeloid cell populations and their functions in atherosclerosis.

Persistent Organic Pollutants in Serum and Several Different Fat Compartments in Humans

DTIC Science & Technology

2011-01-01

vena cava; A: aorta; P: pancreas; K: kidney; L: liver; S: stomach and spleen; C: colon; U: uterus; B: bladder; P: prostate. flame retardants , and...such as dioxins/furans, polychlori- nated biphenyls (PCBs), chlorinated pesticides, brominated Report Documentation Page Form ApprovedOMB No. 0704...perfluorinated compounds. Because of chlorine, bromine , or fluoride groups on the hydrocarbon rings or chains, these substances are resistant to degradation

Treatment of Neuropathic Pain after SCI with a Catalytic Oxidoreductant

DTIC Science & Technology

2015-10-01

opening the scissor. The thoracic aorta was visualized and a small aneurysm clip was placed on the aorta at the level of T8 to induce ischemic injury...into aorta via left ventricle and a small cut was made on right atrium. The vasculature was 6 | P a g e     briefly rinsed with 60 mL saline by

Obstruction of the Aorta and Left Pulmonary Artery After Gianturco Coil Occlusion of Patent Ductus Arteriosus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuo, H.-Cg; Ko, Sheung-Fat; Wu, Yu-Tsun

We report an unusual case of simultaneous obstruction of the left pulmonary artery and descending thoracic aorta after Gianturco coil occlusion in a 15-month-old boy. The diagnosis was made by echocardiography and cardiac angiography. At surgery, thrombi coating on the protruded parts of the Gianturco coil in the pulmonary artery and aorta were found.

Aberrant heartworm migration to the abdominal aorta and systemic arteriolitis in a dog presenting with vomiting and hemorrhagic diarrhea.

PubMed

Grimes, Janet A; Scott, Katherine D; Edwards, John F

2016-01-01

A 2-year-old Dachshund was presented for vomiting and diarrhea. Abdominal ultrasound revealed Dirofilaria immitis in the abdominal aorta and an avascular segment of small intestine. The dog was euthanized. Necropsy revealed D. immitis in the abdominal aorta and widespread necrotizing arteriolitis. This is a unique presentation of aberrant migration of D. immitis.

Why do we live for much less than 100 years? A fluid mechanics view and approach

NASA Astrophysics Data System (ADS)

Messaris, Gerasimos A. T.; Hadjinicolaou, Maria; Karahalios, George T.

2017-08-01

Blood flow in arteries induces shear stresses on the arterial walls. The present work is motivated by the implications of low shear stress on the human arterial system and its effect on the duration of the life of a subject. The low and/or bidirectional wall shear stress stiffens the arterial wall and in synergy with the fluctuating tissue stress due to the fluctuating blood pressure activates the mechanism of aging. If the shear stress were not low and/or bidirectional and if it did not contribute to local endothelium dysfunctions, the tissue stress alone would take more than 100 yr to cause a failure on the human arterial system. Applying the s-n diagram (tissue stress against the number of cycles to failure) to determine the fatigue life of the aorta, for example, we find that in the absence of other pathogenic factors, for a tissue stress 1.2 times bigger than the tissue stress of a non-stiff aorta, the potential 100 yr of life are reduced to nearly 80 yr. Calculation of the rate of variation of the tissue stress of a subject with time may lead to a possible prognosis about the evolution of wall stiffness and its impact on the arterial aging of this subject. Further patient-specific in vivo mechanistic studies complemented by molecular imaging are needed to contribute to the formation of a data base, from which improved models describing the evolution of the arterial stiffness can be developed. Accordingly, the degree of stiffness of the aorta compared with existing data from a corresponding data base may provide with information about the degree of the fatigue of the aortic wall and its possible future behavior and lead to a patient-adapted medical treatment as a means of a would-be preventive medication.

Chronic social isolation in the prairie vole induces endothelial dysfunction: implications for depression and cardiovascular disease

PubMed Central

Peuler, Jacob D.; Scotti, Melissa-Ann L.; Phelps, Laura E.; McNeal, Neal; Grippo, Angela J.

2012-01-01

Humans with depression show impaired endothelium-dependent vasodilation, one recent demonstration of which was in the form of a reduced acetylcholine (ACh)-induced relaxation of adrenergically-precontracted small arteries biopsied from older depressed patients. Results from such uses of ACh in general have been validated as the most predictive marker of endothelium-related cardiovascular diseases. Accordingly, we examined vascular reactivity to ACh in the socially isolated prairie vole, a new animal model relevant to human depression and cardiovascular disease. Thoracic aortas were carefully dissected from female prairie voles after one month of social isolation (versus pairing with a sibling). Only aortas that contracted to the adrenergic agent phenylephrine (PE) and then relaxed to ACh were evaluated. Among those, ACh-induced relaxations were significantly reduced by social isolation (p<0.05), with maximum relaxation reaching only 30% (of PE-induced precontraction) compared to 47% in aortas from paired (control) animals. Experimental removal of the endothelium from an additional set of aortic tissues abolished all ACh relaxations including that difference. In these same tissues, maximally-effective concentrations of the nitric oxide-donor nitroprusside still completely relaxed all PE-induced precontraction of the endothelial-free smooth muscle, and to the same degree in tissues from isolated versus paired animals. Finally, in the absence of PE-induced precontraction ACh did not relax but rather contracted aortic tissues, and to a significantly greater extent in tissues from socially isolated animals if the endothelium was intact (p<0.05). Thus, social isolation in the prairie vole may 1) impair normal release of protective anti-atherosclerotic factors like nitric oxide from the vascular endothelium (without altering the inherent responsiveness of the vascular smooth muscle to such factors) and 2) cause the endothelium to release contracting factors. To our knowledge this is the first demonstration of this phenomenon in an animal model of depression induced solely by social isolation. These findings have implications for understanding mechanisms involved in depression and cardiovascular disease. PMID:22469565

Effects Of Endothelin-1 On Intracellular Tetrahydrobiopterin Levels In Vascular Tissue.

PubMed

Cerrato, Ruha; Crabtree, Mark; Antoniades, Charalambos; Kublickiene, Karolina; Schiffrin, Ernesto L; Channon, Keith M; Böhm, Felix

2018-03-23

Tetrahydrobiopterin (BH4) is the essential cofactor of endothelial nitric oxide synthase (eNOS) and intracellular levels of BH4 is regulated by oxidative stress. The aim of this paper was to describe the influence of exogenous endothelin-1 on intracellular BH4 and its oxidation products dihydrobiopterin (BH2) and biopterin (B) in a wide range of vascular tissue. Segments of internal mammary artery (IMA) and human saphenous vein (SV) from 41 patients undergoing elective surgery were incubated in ET-1 (0.1 μM). Aorta and lung from transgenic mice overexpressing ET-1 in the endothelium (ET-TG) were analysed with regards to intracellular biopterin levels. Human umbilical vein endothelial cells (HUVEC) were incubated in ET-1 (0.1 μM) and intracellular biopterin levels were analysed. From 6 healthy women undergoing caesarean section, subcutaneous fat was harvested and the resistance arteries in these biopsies were tested for ET-mediated endothelial dysfunction. In HUVEC, exogenous ET-1 (0.1 μM) did not significantly change intracellular BH4, 1.54 ± 1.7 vs 1.68 ± 1.8 pmol/mg protein; p = .8. In IMA and SV, exogenous ET-1(0.1 μM) did not change intracellular BH4 n = 10, p = .4. In aorta from wild type vs ET-TG mice there was no significant difference in intracellular BH4 between the groups: 1.3 ± 0.49 vs 1.23 ± 0.3 pmol/mg protein; p = .6. In resistance arteries (n = 6) BH4 together with DTE (an antioxidant) was not able to prevent ET-mediated endothelial dysfunction. ET-1 did not significantly alter intracellular tetrahydrobiopterin levels in IMA, SV, HUVEC or aorta from ET-TG mice. These findings are important for future research in ET-1 mediated superoxide production and endothelial dysfunction.

Noninvasive measurement of regional pulse wave velocity in human ascending aorta with ultrasound imaging: an in-vivo feasibility study.

PubMed

Huang, Chengwu; Guo, Dong; Lan, Feng; Zhang, Hongjia; Luo, Jianwen

2016-10-01

Accurate and noninvasive techniques for measurement of local/regional pulse wave velocity (PWV), instead of global PWV, is desired for quantifying localized arterial stiffness and improving cardiovascular disease assessment. This study aimed at investigating the feasibility of regional PWV measurement in human ascending aorta in vivo using an ultrasound-based technique. Proximal ascending aortas of 76 healthy patients (23-71 years) were scanned with transthoracic echocardiography in parasternal long-axis view, and ultrasound radiofrequency data were acquired in a high temporal resolution (∼404 Hz). The PWV was derived from the determination of arrival times and identification of travel distances. Both PWVs in early systolic phase (PWVsf; pulse wave velocity measured using the systolic foot as characteristic time point) and late systolic phase (PWVdn; pulse wave velocity measured using the dicrotic notch as characteristic time point) were obtained. The PWVsf and PWVdn were 4.58 ± 1.38 and 6.51 ± 1.90 m/s, respectively, and both were correlated with age (r = 0.30, P = 0.02 and r = 0.71, P < 0.0001). The measurements were reproducible, and PWVdn showed significant correlation with aortic diameter (r = 0.53, P < 0.0001), relative distension (r = -0.44, P = 0.0002), and local PWV derived from Bramwell-Hill equation (r = 35, P = 0.004). The PWV difference (PWVdn - PWVsf) reflected aortic stiffness change within cardiac cycle from early systole to late systole and was also correlated with age (r = 0.50, P < 0.0001). The feasibility of ascending aortic PWV measurement using ultrasound imaging was illustrated in vivo, suggesting the potential of the technique in characterization of regional aortic stiffness and assessment of aortic diseases.

The effect of proximal anastomosis on the expansion rate of a dilated ascending aorta in coronary artery bypass surgery: a prospective study

PubMed Central

Balcı, Ahmet Yavuz; Vural, Unsal; Özdemir, MD Fatih; Kızılay, Mehmet; Şenocak, Mutlu; Kayacıoğlu, Ilyas; Yekeler, Ibrahim; Aksoy, Rezan; Satılmış,, Seçkin; Şaşkın, Huseyin

2017-01-01

Summary Background: This study was designed to determine the short- and long-term effects of proximal aortic anastomosis, performed during isolated coronary artery bypass grafting (CABG) in patients with dilatation of the ascending aorta who did not require surgical intervention. Methods: The study was performed on 192 (38 female and 160 male patients; mean age, 62.1 ± 9.2 years; range, 42–80 years) patients with dilatation of the ascending aorta who underwent CABG surgery between 1 June 2006 and 31 May 2014. In group 1 (n = 114), the saphenous vein and left internal mammarian artery grafts were used, and proximal anastomosis was performed on the ascending aorta. In group 2 (n = 78), left and right internal mammarian artery grafts were used, and proximal aortic anastomosis was not performed. Pre-operatively and in the first and third years postoperatively, the ascending aortic diameter was measured and recorded using transthoracic echocardiography at four different regions (annulus, sinus of Valsalva, sinotubular junction and tubular aorta). Results: A statistically significant difference was found between the groups for the number of grafts used and the duration of aortic cross-clamping and cardiopulmonary bypass. No significant intergroup difference was seen for the mean diameter of the ascending aorta (p > 0.05). Annual changes in the aortic diameter were found to be extremely significantly different in both groups (p = 0.0001). Mean values of the aortic diameter at the level of the sinotubular junction and tubular ascending aorta, mean aortic diameters (p = 0.002 and p = 0.0001, respectively), annual increase in diameter (p = 0.0001 and p = 0.0001, respectively), and mean annual difference in diameter (p = 0.0001 and p = 0.0001, respectively) at one and three years postoperatively were statistically significantly different between the groups. Conclusion: In patients with ascending aortic dilatation who did not require surgical intervention and who had proximal anastomosis of the ascending aorta and underwent only CABG, we detected statistically significant increases in the diameter of the sinotubular junction and tubular aorta up to three years postoperatively. PMID:27701487

The Position of the Aorta Relative to the Vertebrae in Patients With Lenke Type 1 Adolescent Idiopathic Scoliosis.

PubMed

Bekki, Hirofumi; Harimaya, Katsumi; Matsumoto, Yoshihiro; Hayashida, Mitsumasa; Okada, Seiji; Doi, Toshio; Iwamoto, Yukihide

2016-04-01

A computed tomography study. The aim of the study was to clarify the position of the aorta relative to the spine in patients with Lenke type 1 adolescent idiopathic scoliosis. Several authors have examined the position of the aorta in patients with scoliosis; however, their analysis included several types of curve. There is a possibility that the position of the aorta differs according to the scoliosis curve type. Thirty-eight patients with Lenke type 1 were analyzed. The angle (left pedicle aorta [LtP-Ao] angle) and distance (LtP-Ao distance) from the insertion point of the left pedicle screw to the aorta were measured from T4 through L2. The measured data were evaluated from 4 levels above to 4 levels below the apical vertebra. The difference between lumbar modifiers A and C was examined. Dangerous pedicles, which were defined as those in which the aorta entered the expected area based on the screw direction error and length, were counted from T10 to L2. The aorta was located posterolaterally and adjacent to the vertebra at the middle thoracic level, and anteromedially and distant at the thoracolumbar level. LtP-Ao angle was largest at 1 level above the apical vertebra, and LtP-Ao distance was shortest at 2 levels above. LtP-Ao angle of Lenke 1A was significantly larger than 1C from T11 to L2, and LtP-Ao distance of 1A was significantly shorter than 1C from T11 to L1. When the screw length was 40 mm and the direction error was within 10°, there were a large number of dangerous pedicles at T11, regardless of the lumbar modifier. The direction error has a potential risk of injuring the aorta around the apical vertebra. The selection of screws of the proper length is necessary to avoid a breach of the anterior vertebral wall at thoracolumbar level, especially at T11. 3.

The effect of proximal anastomosis on the expansion rate of a dilated ascending aorta in coronary artery bypass surgery: a prospective study.

PubMed

Yavuz Balci, Ahmet; Vural, Unsal; Aksoy, Rezan; Özdemir, M Fatih; Satilmiş, Seçkin; Kizilay, Mehmet; Şenocak, Mutlu; Şaşkin, Huseyin; Kayacioğlu, Ilyas; Yekeler, Ibrahim

This study was designed to determine the short- and long-term effects of proximal aortic anastomosis, performed during isolated coronary artery bypass grafting (CABG) in patients with dilatation of the ascending aorta who did not require surgical intervention. The study was performed on 192 (38 female and 160 male patients; mean age, 62.1 ± 9.2 years; range, 42-80 years) patients with dilatation of the ascending aorta who underwent CABG surgery between 1 June 2006 and 31 May 2014. In group 1 (n = 114), the saphenous vein and left internal mammarian artery grafts were used, and proximal anastomosis was performed on the ascending aorta. In group 2 (n = 78), left and right internal mammarian artery grafts were used, and proximal aortic anastomosis was not performed. Pre-operatively and in the first and third years postoperatively, the ascending aortic diameter was measured and recorded using transthoracic echocardiography at four different regions (annulus, sinus of Valsalva, sinotubular junction and tubular aorta). A statistically significant difference was found between the groups for the number of grafts used and the duration of aortic cross-clamping and cardiopulmonary bypass. No significant intergroup difference was seen for the mean diameter of the ascending aorta (p > 0.05). Annual changes in the aortic diameter were found to be extremely significantly different in both groups (p = 0.0001). Mean values of the aortic diameter at the level of the sinotubular junction and tubular ascending aorta, mean aortic diameters (p = 0.002 and p = 0.0001, respectively), annual increase in diameter (p = 0.0001 and p = 0.0001, respectively), and mean annual difference in diameter (p = 0.0001 and p = 0.0001, respectively) at one and three years postoperatively were statistically significantly different between the groups. In patients with ascending aortic dilatation who did not require surgical intervention and who had proximal anastomosis of the ascending aorta and underwent only CABG, we detected statistically significant increases in the diameter of the sinotubular junction and tubular aorta up to three years postoperatively.

Gamma Low-Dose-Rate Ionizing Radiation Stimulates Adaptive Functional and Molecular Response in Human Aortic Endothelial Cells in a Threshold-, Dose-, and Dose Rate–Dependent Manner

PubMed Central

Vieira Dias, Juliana; Gloaguen, Celine; Kereselidze, Dimitri; Manens, Line; Tack, Karine; Ebrahimian, Teni G

2018-01-01

A central question in radiation protection research is whether low-dose and low-dose-rate (LDR) exposures to ionizing radiation play a role in progression of cardiovascular disease. The response of endothelial cells to different LDR exposures may help estimate risk of cardiovascular disease by providing the biological mechanism involved. We investigated the effect of chronic LDR radiation on functional and molecular responses of human aorta endothelial cells (HAoECs). Human aorta endothelial cells were continuously irradiated at LDR (6 mGy/h) for 15 days and analyzed at time points when the cumulative dose reached 0.05, 0.5, 1.0, and 2.0 Gy. The same doses were administered acutely at high-dose rate (HDR; 1 Gy/min). The threshold for the loss of angiogenic capacity for both LDR and HDR radiations was between 0.5 and 1.0 Gy. At 2.0 Gy, angiogenic capacity returned to normal only for HAoEC exposed to LDR radiation, associated with increased expression of antioxidant and anti-inflammatory genes. Pre-LDR, but not pre-HDR, radiation, followed by a single acute 2.0 Gy challenge dose sustained the expression of antioxidant and anti-inflammatory genes and stimulated angiogenesis. Our results suggest that dose rate is important in cellular response and that a radioadaptive response is involved for a 2.0 Gy dose at LDR. PMID:29531508

Gamma Low-Dose-Rate Ionizing Radiation Stimulates Adaptive Functional and Molecular Response in Human Aortic Endothelial Cells in a Threshold-, Dose-, and Dose Rate-Dependent Manner.

PubMed

Vieira Dias, Juliana; Gloaguen, Celine; Kereselidze, Dimitri; Manens, Line; Tack, Karine; Ebrahimian, Teni G

2018-01-01

A central question in radiation protection research is whether low-dose and low-dose-rate (LDR) exposures to ionizing radiation play a role in progression of cardiovascular disease. The response of endothelial cells to different LDR exposures may help estimate risk of cardiovascular disease by providing the biological mechanism involved. We investigated the effect of chronic LDR radiation on functional and molecular responses of human aorta endothelial cells (HAoECs). Human aorta endothelial cells were continuously irradiated at LDR (6 mGy/h) for 15 days and analyzed at time points when the cumulative dose reached 0.05, 0.5, 1.0, and 2.0 Gy. The same doses were administered acutely at high-dose rate (HDR; 1 Gy/min). The threshold for the loss of angiogenic capacity for both LDR and HDR radiations was between 0.5 and 1.0 Gy. At 2.0 Gy, angiogenic capacity returned to normal only for HAoEC exposed to LDR radiation, associated with increased expression of antioxidant and anti-inflammatory genes. Pre-LDR, but not pre-HDR, radiation, followed by a single acute 2.0 Gy challenge dose sustained the expression of antioxidant and anti-inflammatory genes and stimulated angiogenesis. Our results suggest that dose rate is important in cellular response and that a radioadaptive response is involved for a 2.0 Gy dose at LDR.

A mechanistic model on the role of “radially-running” collagen fibers on dissection properties of human ascending thoracic aorta

PubMed Central

Pal, Siladitya; Tsamis, Alkiviadis; Pasta, Salvatore; D'Amore, Antonio; Gleason, Thomas G.; Vorp, David A.; Maiti, Spandan

2014-01-01

Aortic dissection (AoD) is a common condition that often leads to life-threatening cardiovaular emergency. From a biomechanics viewpoint, AoD involves failure of load-bearing microstructural components of the aortic wall, mainly elastin and collagen fibers. Delamination strength of the aortic wall depends on the load-bearing capacity and local micro-architecture of these fibers, which may vary with age, disease and aortic location. Therefore, quantifying the role of fiber micro-architecture on the delamination strength of the aortic wall may lead to improved understanding of AoD. We present an experimentally-driven modeling paradigm towards this goal. Specifically, we utilize collagen fiber microarchitecture, obtained in a parallel study from multi-photon microopy, in a predictive mechanistic framework to characterize the delamination strength. We then validate our model against peel test experiments on human aortic strips and utilize the model to predict the delamination strength of separate aortic strips and compare with experimental findings. We observe that the number density and failure energy of the radially-running collagen fibers control the peel strength. Furthermore, our model suggests that the lower delamination strength previously found for the circumferential direction in human aorta is related to a lower number density of radially-running collagen fibers in that direction. Our model sets the stage for an expanded future study that could predict AoD propagation in patient-specific aortic geometries and better understand factors that may influence propensity for occurrence. PMID:24484644

Restricted intra-embryonic origin of bona fide hematopoietic stem cells in the chicken

PubMed Central

Yvernogeau, Laurent

2017-01-01

Hematopoietic stem cells (HSCs), which are responsible for blood cell production, are generated during embryonic development. Human and chicken embryos share features that position the chicken as a reliable and accessible alternative model to study developmental hematopoiesis. However, the existence of HSCs has never been formally proven in chicken embryos. Here, we have established a complete cartography and quantification of hematopoietic cells in the aorta during development. We demonstrate the existence of bona fide HSCs, originating from the chicken embryo aorta (and not the yolk sac, allantois or head), through an in vivo transplantation assay. Embryos transplanted in ovo with GFP embryonic tissues on the chorio-allantoic membrane provided multilineage reconstitution in adulthood. Historically, most breakthrough discoveries in the field of developmental hematopoiesis were first made in birds and later extended to mammals. Our study sheds new light on the avian model as a valuable system to study HSC production and regulation in vivo. PMID:28526756

Expression profile analysis of aorta-gonad-mesonephros region-derived stromal cells reveals genes that regulate hematopoiesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nagao, Kenji; Ohta, Takayuki; Hinohara, Atsushi

The aorta-gonad-mesonephros (AGM) region is involved in the generation and maintenance of the first definitive hematopoietic stem cells (HSCs). A mouse AGM-derived cell line, AGM-S3, was shown to support the development of HSCs. To elucidate the molecular mechanisms regulating early hematopoiesis, we obtained subclones from AGM-S3, one of which was hematopoiesis supportive (S3-A9) and the other one of which was non-supportive (S3-A7), and we analyzed their gene expression profiles by gene chip analysis. In the present study, we found that Glypican-1 (GPC1) was highly expressed in the supportive subclone AGM-S3-A9. Over-expression of GPC1 in non-supportive cells led to the proliferationmore » of progenitor cells in human cord blood when cocultured with the transfected-stromal cells. Thus, GPC1 may have an important role in the establishment of a microenvironment that supports early events in hematopoiesis.« less

Impaired muscarinic endothelium-dependent relaxation and cyclic guanosine 5'-monophosphate formation in atherosclerotic human coronary artery and rabbit aorta.

PubMed Central

Bossaller, C; Habib, G B; Yamamoto, H; Williams, C; Wells, S; Henry, P D

1987-01-01

The dependence of vascular relaxation on an intact endothelium and the relationship between relaxation and cyclic GMP accumulation were determined in coronary arteries isolated from cardiac transplantation patients with or without coronary atherosclerosis. In nonatherosclerotic arteries, the endothelium-dependent agent acetylcholine produced concentration-related relaxations. In atherosclerotic arteries, endothelium-dependent relaxations were abolished with acetylcholine, partly suppressed with substance P and histamine, and completely preserved with the ionophore A23187. In these arteries, the endothelium-independent agent nitroglycerin remained fully active. Accumulation of cyclic GMP in atherosclerotic strips was suppressed with acetylcholine but unattenuated with A23187 and nitroglycerin. In aortas from rabbits with diet-induced atherosclerosis, there was likewise an impaired cholinergic relaxation and cyclic GMP accumulation in the presence of preserved responses to A23187 and nitroglycerin. The results demonstrate that impaired cholinergic responses in atherosclerotic arteries reflect a muscarinic defect and not an inability of endothelium to release endothelial factor or smooth muscle to respond to it. PMID:2432088

Optical pathology study of human abdominal aorta tissues using confocal micro resonance Raman spectroscopy

NASA Astrophysics Data System (ADS)

Liu, Cheng-hui; Boydston-White, Susie; Wang, Wubao; Sordillo, Laura A.; Shi, Lingyan; Weisberg, Arel; Tomaselli, Vincent P.; Sordillo, Peter P.; Alfano, Robert R.

2016-03-01

Resonance Raman (RR) spectroscopic technique has a high potential for label-free and in-situ detection of biomedical lesions in vivo. This study evaluates the ability of RR spectroscopy method as an optical histopathology tool to detect the atherosclerotic plaque states of abdominal aorta in vitro. This part demonstrates the RR spectral molecular fingerprint features from different sites of the atherosclerotic abdominal aortic wall tissues. Total 57 sites of five pieces aortic samples in intimal and adventitial wall from an autopsy specimen were examined using confocal micro Raman system of WITec 300R with excitation wavelength of 532nm. The preliminary RR spectral biomarkers of molecular fingerprints indicated that typical calcified atherosclerotic plaque (RR peak at 964cm-1) tissue; fibrolipid plaque (RR peaks at 1007, 1161, 1517 and 2888cm-1) tissue, lipid pool with the fatty precipitation cholesterol) with collagen type I (RR peaks at 864, 1452, 1658, 2888 and 2948cm-1) in the soft tissue were observed and investigated.

Antihypertensive and vasorelaxant effects of water-soluble proanthocyanidins from persimmon leaf tea in spontaneously hypertensive rats.

PubMed

Kawakami, Kayoko; Aketa, Saiko; Sakai, Hiroki; Watanabe, Yusuke; Nishida, Hiroshi; Hirayama, Masao

2011-01-01

The antihypertensive and vasorelaxant effects of water-soluble proanthocyanidins, extracted in persimmon leaf tea, were investigated in spontaneously hypertensive rats, rat aortas, and human umbilical vein endothelial cells. Oral administration of proanthocyanidins significantly decreased the systolic blood pressure of the rats after 4 h, as compared with distilled water controls. A vasorelaxant effect on rat aortas was induced by proanthocyanidins, and it was abolished by removal of the endothelium and inhibition of endothelial nitric oxide synthase and soluble guanylyl cyclase activity. The phosphorylation levels of endothelial nitric oxide synthase (Ser-1177) and the upstream kinase Akt (Ser-473) in umbilical cells also increased in a time-dependent manner after the addition of a proanthocyanidin-rich fraction. These results suggest that the antihypertensive effect of proanthocyanidins in persimmon leaf tea is due to vasorelaxation via an endothelium-dependent nitric oxide/cGMP pathway, and that proanthocyanidins might be useful in dietary lowering of blood pressure.

Severe Obstructive Calcification of the Descending Aorta: A Case Report of “Coral Reef Aorta”

PubMed Central

Ishigaki, Takahiro; Matsuda, Hitoshi; Henmi, Soichiro; Yoshida, Masato; Mukohara, Nobuhiko

2017-01-01

An 82-year-old man suffering from lower back pain and dyspnea presented to our institute in a state of shock. Computed tomography showed subtotal occlusion of the descending aorta with massive atherosclerotic calcification. As the proximal portion of the superior mesenteric artery was obstructed, emergency bypass from the right axillary artery to the bilateral external iliac arteries was performed, but the patient died 2 days later. Autopsy revealed that reddish-brown and verrucous masses obstructed the descending aorta, and high-grade thickening of the intima and extensive deposits of calcium in the lumina and medial layer were detected in the descending aorta histologically. PMID:29034045

Protection against atherogenesis with the polymer drag-reducing agent Separan AP-30.

PubMed

Faruqui, F I; Otten, M D; Polimeni, P I

1987-03-01

The inhibitory effect of Separan AP-30, an anionic polyacrylamide, on atherosclerotic plaque formation in aortas of rabbits on a high (2%) cholesterol diet was tested over a period extending from 37 to 170 days. Atherogenesis was quantified morphometrically by application of a computer-assisted image analysis of histologic cross sections of the aorta. The area of vessel wall-atheroma interface, fraction of lumen occluded, and other indexes of atherogenesis were measured in each of 26 segments of aorta excised from the animals, half of which were administered injections (intravenous) of Separan three times a week. Regression analysis of the morphometric data indicates that the polyelectrolyte exerts a powerful antiatherogenic effect in all regions of the aorta, inhibiting the formation of plaque mass to less than half in the aortic arch and about one-fifth in the descending aorta as compared with the aortic plaque masses in untreated rabbits. Results are compatible with the suggestion that a novel hemodynamic principle in vivo, polymer drag reduction, might be effectively applied against atherosclerosis.

Epiaortic fat pad area: A novel index for the dimensions of the ascending aorta.

PubMed

Toufan, Mehrnoush; Pourafkari, Leili; Boudagh, Shabnam; Nader, Nader D

2016-06-01

We sought to investigate the possible association between the area of the epiaortic fat pad (EAFP) and dimensions of the ascending aorta. A total of 193 individuals underwent transthoracic echocardiography (TTE) prospectively. The area of the EAFP was traced anterior to the aortic root and correlated with the diameter of the aorta. The mean area of the EAFP was 5.16 ± 2.28 cm(2) Absolute and indexed dimensions of the ascending aorta had a significant correlation with the area of the EAFP (p <0.001 for all). In a multivariate linear regression model, age >65 (p <0.001), body mass index >30 kg/m(2) (p = 0.02) and a history of hyperlipidemia (p = 0.003) were identified as independent predictors of the area for EAFP. In conclusion, both the absolute and indexed diameters of the ascending aorta at the different segments that directly come into contact with the EAFP linearly correlate with the area of the EAFP measured by TTE. © The Author(s) 2016.

Selenium Deficiency Influences the Expression of Selenoproteins and Inflammatory Cytokines in Chicken Aorta Vessels.

PubMed

Du, Qiang; Yao, Haidong; Yao, Linlin; Zhang, Ziwei; Lei, Xingen; Xu, Shiwen

2016-10-01

Selenium deficiency is known to cause cardiovascular diseases. However, the role of Se deficiency in causing oxidative damage and inflammation injury to the aorta vessels of chickens is not well known. In the present study, 180 1-day-old chickens were randomly divided into two groups, a low-Se group (L group) and a control-Se group (C group). The messenger RNA (mRNA) levels of 25 selenoproteins, the mRNA and protein expression levels of inflammatory cytokines (including NF-κB, TNF-α, COX-2, and PTGES), and the antioxidant levels in chicken aorta vessels were examined. The results showed that the mRNA levels of 25 selenoproteins and the activity of Gpx were decreased, while the mRNA and protein expression levels of inflammatory cytokines and the MDA content were increased by Se deficiency in chicken aorta vessels. The data from the present study indicated that Se deficiency decreases the expression of selenoproteins, reduces antioxidant function, and increases the expression of inflammatory factors in chicken aorta vessels.

Interactions between mural cells and endothelial cells stabilize the developing zebrafish dorsal aorta

PubMed Central

Stratman, Amber N.; Pezoa, Sofia A.; Farrelly, Olivia M.; Castranova, Daniel; Dye, Louis E.; Butler, Matthew G.; Sidik, Harwin; Talbot, William S.

2017-01-01

Mural cells (vascular smooth muscle cells and pericytes) play an essential role in the development of the vasculature, promoting vascular quiescence and long-term vessel stabilization through their interactions with endothelial cells. However, the mechanistic details of how mural cells stabilize vessels are not fully understood. We have examined the emergence and functional role of mural cells investing the dorsal aorta during early development using the zebrafish. Consistent with previous literature, our data suggest that cells ensheathing the dorsal aorta emerge from a sub-population of cells in the adjacent sclerotome. Inhibition of mural cell recruitment to the dorsal aorta through disruption of pdgfr signaling leads to a reduced vascular basement membrane, which in turn results in enhanced dorsal aorta vessel elasticity and failure to restrict aortic diameter. Our results provide direct in vivo evidence for a functional role for mural cells in patterning and stabilization of the early vasculature through production and maintenance of the vascular basement membrane to prevent abnormal aortic expansion and elasticity. PMID:27913637

Resuscitative Endovascular Balloon Occlusion of the Aorta: A Bridge to Flight Survival.

PubMed

Goforth, Carl; Bradley, Matthew; Pineda, Benilani; See, Suzanne; Pasley, Jason

2018-04-01

Trauma endures as the leading cause of death worldwide, and most deaths occur in the first 24 hours after initial injury as a result of hemorrhage. Historically, about 90% of battlefield deaths occur before the injured person arrives at a theater hospital, and most are due to noncompressible hemorrhage of the torso. Resuscitative endovascular balloon occlusion of the aorta is an evolving technique to quickly place a balloon into the thoracic or abdominal aorta to efficiently block blood flow to distal circulation. Maneuvers, such as resuscitative endovascular balloon occlusion of the aorta, to control endovascular hemorrhage offer a potential intervention to control noncompressible hemorrhage. This technique can be performed percutaneously or open in prehospital environments to restore hemodynamic functions and serve as a survival bridge until the patient is delivered to a treatment facility for definitive surgical hemostasis. This article describes the indications, complications, and application of resuscitative endovascular balloon occlusion of the aorta to military and civilian aeromedical transport. ©2018 American Association of Critical-Care Nurses.

Effects of Aortic Irregularities on the Blood Flow

NASA Astrophysics Data System (ADS)

Gutmark-Little, Iris; Prahl-Wittberg, Lisa; van Wyk, Stevin; Mihaescu, Mihai; Fuchs, Laszlo; Backeljauw, Philippe; Gutmark, Ephraim

2013-11-01

Cardiovascular defects characterized by geometrical anomalies of the aorta and its effect on the blood flow are investigated. The flow characteristics change with the aorta geometry and the rheological properties of the blood. Flow characteristics such as wall shear stress often play an important role in the development of vascular disease. In the present study, blood is considered to be non-Newtonian and is modeled using the Quemada model, an empirical model that is valid for different red blood cell loading. Three patient-specific aortic geometries are studied using Large Eddy Simulations (LES). The three geometries represent malformations that are typical in patients populations having a genetic disorder called Turner syndrome. The results show a highly complex flow with regions of recirculation that are enhanced in two of the three aortas. Moreover, blood flow is diverted, due to the malformations, from the descending aorta to the three side branches of the arch. The geometry having an elongated transverse aorta has larger areas of strong oscillatory wall shear stress.

Reduction of thoracic aorta motion artifact with high-pitch 128-slice dual-source computed tomographic angiography: a historical control study.

PubMed

Nakagawa, Junichiro; Tasaki, Osamu; Watanabe, Yoshiyuki; Azuma, Takeo; Ohnishi, Mitsuo; Ukai, Isao; Tahara, Kenichi; Ogura, Hiroshi; Kuwagata, Yasuyuki; Hamasaki, Toshimitsu; Shimazu, Takeshi

2013-01-01

Electrocardiogram-gated imaging combined with multi-detector row computed tomography (MDCT) has reduced cardiac motion artifacts, but it was not practical in the emergency setting. The purpose of this study was to evaluate the ability of a high-pitch, 128-slice dual-source CT (DSCT) scanner to reduce motion artifacts in patients admitted to the emergency room. This study comprised 100 patients suspected of having thoracic aorta lesions. We examined 47 patients with the 128-slice DSCT scanner (DSCT group), and 53 patients were examined with a 64-slice MDCT scanner (MDCT group). Six anatomic areas in the thoracic aorta were evaluated. Computed tomography images in the DSCT group were distinct, and significant differences were observed in images of all areas between the 2 groups except for the descending aorta. The high-pitch DSCT scanner can reduce motion artifacts of the thoracic aorta and enable radiological diagnosis even in patients with tachycardia and without breath hold.

A Hybrid Windkessel Model of Blood Flow in Arterial Tree Using Velocity Profile Method

NASA Astrophysics Data System (ADS)

Aboelkassem, Yasser; Virag, Zdravko

2016-11-01

For the study of pulsatile blood flow in the arterial system, we derived a coupled Windkessel-Womersley mathematical model. Initially, a 6-elements Windkessel model is proposed to describe the hemodynamics transport in terms of constant resistance, inductance and capacitance. This model can be seen as a two compartment model, in which the compartments are connected by a rigid pipe, modeled by one inductor and resistor. The first viscoelastic compartment models proximal part of the aorta, the second elastic compartment represents the rest of the arterial tree and aorta can be seen as the connection pipe. Although the proposed 6-elements lumped model was able to accurately reconstruct the aortic pressure, it can't be used to predict the axial velocity distribution in the aorta and the wall shear stress and consequently, proper time varying pressure drop. We then modified this lumped model by replacing the connection pipe circuit elements with a vessel having a radius R and a length L. The pulsatile flow motions in the vessel are resolved instantaneously along with the Windkessel like model enable not only accurate prediction of the aortic pressure but also wall shear stress and frictional pressure drop. The proposed hybrid model has been validated using several in-vivo aortic pressure and flow rate data acquired from different species such as, humans, dogs and pigs. The method accurately predicts the time variation of wall shear stress and frictional pressure drop. Institute for Computational Medicine, Dept. Biomedical Engineering.

Medical Simulation for Trauma Management.

DTIC Science & Technology

1997-10-01

the inferior mesenteric vein and identify the aorta. Indications for surgical exploration of major trauma (McAninch and Carroll (1989...aorta. (5) Vascular control is obtained by clamping the renal vein and artery at their origins from the vena cava and the aorta, (mistake possible...as if they are being miniaturized and injected into the heart’s left atrium . Their mission, in Page 21 order to save the patient, is to maneuver

A computational simulation of the effect of hybrid treatment for thoracoabdominal aortic aneurysm on the hemodynamics of abdominal aorta

NASA Astrophysics Data System (ADS)

Wen, Jun; Yuan, Ding; Wang, Qingyuan; Hu, Yao; Zhao, Jichun; Zheng, Tinghui; Fan, Yubo

2016-03-01

Hybrid visceral-renal debranching procedures with endovascular repair have been proposed as an appealing technique to treat conventional thoracoabdominal aortic aneurysm (TAAA). This approach, however, still remained controversial because of the non-physiological blood flow direction of its retrograde visceral revascularization (RVR) which is generally constructed from the aortic bifurcation or common iliac artery. The current study carried out the numerical simulation to investigate the effect of RVR on the hemodynamics of abdominal aorta. The results indicated that the inflow sites for the RVR have great impact on the hemodynamic performance. When RVR was from the distal aorta, the perfusion to visceral organs were adequate but the flow flux to the iliac artery significantly decreased and a complex disturbed flow field developed at the distal aorta, which endangered the aorta at high risk of aneurysm development. When RVR was from the right iliac artery, the abdominal aorta was not troubled with low WSS or disturbed flow, but the inadequate perfusion to the visceral organs reached up to 40% and low WSS and flow velocity predominated appeared at the right iliac artery and the grafts, which may result in the stenosis in grafts and aneurysm growth on the host iliac artery.

[Endovascular and surgical treatment of a patient with traumatic rupture of the aorta and hepatic artery].

PubMed

Chernaya, N R; Muslimov, R Sh; Selina, I E; Kokov, L S; Vladimirova, E S; Navruzbekov, M S; Gulyaev, V A

2016-01-01

Traumatic rupture of the aorta is the second most common cause of death in closed chest injury. The latest findings of autopsy showed that 80% of lethal outcomes in aortic injury occur in the prehospital period. Taking into consideration the incidence and high rate of death prior to the diagnosis stage, aortic rupture in closed thoracic injury is an important problem. Due to the characteristic mechanism of the development (during sharp deceleration of the body) this type of traumatic lesion of the aorta became known as "deceleration syndrome". The most vulnerable to tension aortic portion is its neck where the mobile part of the thoracic aorta is connected to the fixed arch in the place of the arterial ligament attachment. Open surgical intervention in patients with severe closed chest injury (often concomitant injury) is associated with high mortality and complications. Currently endovascular prosthetic repair of the aorta is a method of choice at the primary stage of treatment of patients with aortic injury. In this article we present a rare case report of concomitant lesion of large vessels (the descending aortic portion and proper hepatic artery) in a patient with severe concomitant injury, as well as peculiarities of diagnosis and combined treatment (endovascular prosthetic repair of the aorta and hepatic artery with an aotovein).

Vasodilator activity of the essential oil from aerial parts of Pectis brevipedunculata and its main constituent citral in rat aorta.

PubMed

Pereira, Sharlene Lopes; Marques, André Mesquita; Sudo, Roberto Takashi; Kaplan, Maria Auxiliadora Coelho; Zapata-Sudo, Gisele

2013-03-07

The essential oil of Pectis brevipedunculata (EOPB), a Brazilian ornamental aromatic grass, is characterized by its high content of citral (81.9%: neral 32.7% and geranial 49.2%), limonene (4.7%) and α-pinene (3.4%). Vasodilation induced by EOPB and isolated citral was investigated in pre-contracted vascular smooth muscle, using thoracic aorta from Wistar Kyoto (WKY) rats which was prepared for isometric tension recording. EOPB promoted intense relaxation of endothelium-intact and denuded aortic rings with the concentration to induce 50% of the maximal relaxation (IC50) of 0.044% ± 0.006% and 0.093% ± 0.015% (p < 0.05), respectively. The IC50 values for citral in endothelium-intact and denuded rings were 0.024% ± 0.004% and 0.021% ± 0.004%, respectively (p > 0.05). In endothelium-intact aorta, EOPB-induced vasorelaxation was significantly reduced by L-NAME, a nitric oxide synthase inhibitor. The vasodilator activity of citral was increased in the KCl-contracted aorta and citral attenuated the contracture elicited by Ca2+ in depolarized aorta. EOPB and citral elicited vasorelaxation on thoracic aorta by affecting the NO/cyclic GMP pathway and the calcium influx through voltage-dependent L-type Ca2+ channels, respectively.

Endothelium-Dependent and -Independent Vasodilator Effects of Dimethyl Sulfoxide in Rat Aorta.

PubMed

Kaneda, Takeharu; Sasaki, Noriyasu; Urakawa, Norimoto; Shimizu, Kazumasa

2016-01-01

This study examined the mechanism of vasorelaxation induced by dimethyl sulfoxide (DMSO) in endothelium-intact and -denuded rat aorta. DMSO (0.1-3%) inhibited phenylephrine (PE, 1 μmol/l)-induced contraction in a dose-dependent manner. However, this relaxation was lower in the absence of the endothelium. Increase in DMSO-induced relaxation in the presence of the endothelium was attenuated by preincubation in L-NG-nitroarginine methyl ester (L-NAME, 100 μmol/l) and by the removal of the endothelium. In the aorta with endothelium, DMSO (3%) and CCh (3 μmol/l) increased cGMP contents, significantly and L-NAME (100 μmol/l) inhibited the DMSO-induced increases of cGMP. In fura 2-loaded endothelium-denuded aorta, cumulative application of DMSO (1-3%) inhibited PE-induced muscle tension; however, this application did not affect the [Ca2+]i level. In PE-precontracted endothelium-denuded aorta, relaxation responses to fasudil were significantly less in the presence of DMSO compared to the control. These results suggest that DMSO causes relaxation by increasing the cGMP content in correlation with the release of NO from endothelial cells and by decreasing the Ca2+ sensitivity of contractile elements partly via inhibiting Rho-kinase in rat aorta. © 2016 S. Karger AG, Basel.

Pulsatile Hyperglycaemia Induces Vascular Oxidative Stress and GLUT 1 Expression More Potently than Sustained Hyperglycaemia in Rats on High Fat Diet

PubMed Central

Rakipovski, Günaj; Lykkesfeldt, Jens; Raun, Kirsten

2016-01-01

Introduction Pulsatile hyperglycaemia resulting in oxidative stress may play an important role in the development of macrovascular complications. We investigated the effects of sustained vs. pulsatile hyperglycaemia in insulin resistant rats on markers of oxidative stress, enzyme expression and glucose metabolism in liver and aorta. We hypothesized that liver’s ability to regulate the glucose homeostasis under varying states of hyperglycaemia may indirectly affect oxidative stress status in aorta despite the amount of glucose challenged with. Methods Animals were infused with sustained high (SHG), low (SLG), pulsatile (PLG) glucose or saline (VEH) for 96 h. Oxidative stress status and key regulators of glucose metabolism in liver and aorta were investigated. Results Similar response in plasma lipid oxidation was observed in PLG as in SHG. Likewise, in aorta, PLG and SHG displayed increased expression of glucose transporter 1 (GLUT1), gp-91PHOX and super oxide dismutase (SOD), while only the PLG group showed increased accumulation of oxidative stress and oxidised low density lipoprotein (oxLDL) in aorta. Conclusion Pulsatile hyperglycaemia induced relatively higher levels of oxidative stress systemically and in aorta in particular than overt sustained hyperglycaemia thus supporting the clinical observations that pulsatile hyperglycaemia is an independent risk factor for diabetes related macrovascular complications. PMID:26790104

Pulsatile Hyperglycaemia Induces Vascular Oxidative Stress and GLUT 1 Expression More Potently than Sustained Hyperglycaemia in Rats on High Fat Diet.

PubMed

Rakipovski, Günaj; Lykkesfeldt, Jens; Raun, Kirsten

2016-01-01

Pulsatile hyperglycaemia resulting in oxidative stress may play an important role in the development of macrovascular complications. We investigated the effects of sustained vs. pulsatile hyperglycaemia in insulin resistant rats on markers of oxidative stress, enzyme expression and glucose metabolism in liver and aorta. We hypothesized that liver's ability to regulate the glucose homeostasis under varying states of hyperglycaemia may indirectly affect oxidative stress status in aorta despite the amount of glucose challenged with. Animals were infused with sustained high (SHG), low (SLG), pulsatile (PLG) glucose or saline (VEH) for 96 h. Oxidative stress status and key regulators of glucose metabolism in liver and aorta were investigated. Similar response in plasma lipid oxidation was observed in PLG as in SHG. Likewise, in aorta, PLG and SHG displayed increased expression of glucose transporter 1 (GLUT1), gp-91PHOX and super oxide dismutase (SOD), while only the PLG group showed increased accumulation of oxidative stress and oxidised low density lipoprotein (oxLDL) in aorta. Pulsatile hyperglycaemia induced relatively higher levels of oxidative stress systemically and in aorta in particular than overt sustained hyperglycaemia thus supporting the clinical observations that pulsatile hyperglycaemia is an independent risk factor for diabetes related macrovascular complications.

Ca(2+)-channel blockade in rat thoracic aorta by protopine isolated from Corydalis tubers.

PubMed

Ko, F N; Wu, T S; Lu, S T; Wu, Y C; Huang, T F; Teng, C M

1992-01-01

The pharmacological properties and mechanism of the action of protopine on isolated rat thoracic aorta were examined. It inhibited norepinephrine (NE, 3 microM)-induced tonic contraction in rat thoracic aorta in a concentration-dependent manner (25-100 micrograms/ml). The phasic contraction caused by NE was inhibited only by a high concentration of protopine (100 micrograms/ml). At the plateau of NE-induced tonic contraction, the addition of protopine also caused relaxation. This relaxing effect of protopine was not antagonized by indomethacin (20 microM) or methylene blue (50 microM), and it still existed in denuded rat aorta or in the presence of nifedipine (2-100 microM). Protopine also inhibited high potassium (60 mM)-induced, calcium-dependent (0.03-3 mM) contraction of rat aorta in a concentration-dependent manner. Neither cAMP nor cGMP level was changed by protopine. Both the formation of inositol monophosphate caused by NE and the phasic contraction induced by caffeine were also not affected by protopine. 45Ca2+ influx caused by either NE or K+ was inhibited by protopine concentration-dependently. It is concluded that protopine relaxed the rat thoracic aorta mainly by suppressing the Ca2+ influx through both voltage- and receptor-operated calcium channels.

Aortic expansion rate in patients with dilated post-stenotic ascending aorta submitted only to aortic valve replacement long-term follow-up.

PubMed

Gaudino, Mario; Anselmi, Amedeo; Morelli, Mauro; Pragliola, Claudio; Tsiopoulos, Vasileios; Glieca, Franco; Possati, Gianfederico

2011-08-02

This study was conceived to describe the evolution of aortic dimensions in patients with moderate post-stenotic ascending aorta dilation (50 to 59 mm) submitted to aortic valve replacement (AVR) alone. The appropriate treatment of post-stenotic ascending aorta dilation has been poorly investigated. Ninety-three patients affected by severe isolated calcific aortic valve stenosis in the tricuspid aortic valve accompanied by moderate dilation of the ascending aorta (50 to 59 mm) were submitted to AVR only. All patients were followed for a mean of 14.7 ± 4.8 years by means of periodic clinical evaluations and echocardiography and tomography scans of the thorax. Operative mortality was 1.0% (1 patient). During the follow-up, 16 patients died and 2 had to be reoperated for valve dysfunction. No patients experienced acute aortic events (rupture, dissection, pseudoaneurysm), and no patient had to be reoperated on the aorta. There was not a substantial increase in aortic dimensions: mean aortic diameter was 57 ± 11 mm at the end of the follow-up versus 56 ± 02 mm pre-operatively (p = NS). The mean ascending aorta expansion rate was 0.3 ± 0.2 mm/year. In the absence of connective tissue disorders, AVR alone is sufficient to prevent further aortic expansion in patients with moderate post-stenotic dilation of the ascending aorta. Aortic replacement can probably be reserved for patients with a long life expectancy. Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Comparative Study of Continuous and Pulsatile Left Ventricular Assist Devices on Hemodynamics of a Pediatric End-to-Side Anastomotic Graft

PubMed Central

Yang, Ning; Deutsch, Steven; Paterson, Eric G.; Manning, Keefe B.

2013-01-01

Although there are many studies that focus on understanding the consequence of pumping mode (continuous vs. pulsatile) associated with ventricular assist devices (VADs) on pediatric vascular pulsatility, the impact on local hemodynamics has been largely ignored. Hence, we compare not only the hemodynamic parameters indicative of pulsatility but also the local flow fields in the aorta and the great vessels originating from the aortic arch. A physiologic graft anastomotic model is constructed based on a pediatric, patient specific, aorta with a graft attached on the ascending aorta. The flow is simulated using a previously validated second-order accurate Navier–Stokes flow solver based upon a finite volume approach. The major findings are: (1) pulsatile support provides a greater degree of vascular pulsatility when compared to continuous support, which, however, is still 20% less than pulsatility in the healthy aorta; (2) pulsatile support increases the flow in the great vessels, while continuous support decreases it; (3) complete VAD support results in turbulence in the aorta, with maximum principal Reynolds stresses for pulsatile support and continuous support of 7081 and 249 dyn/cm2, respectively; (4) complete pulsatile support results in a significant increase in predicted hemolysis in the aorta; and (5) pulsatile support causes both higher time-averaged wall shear stresses (WSS) and oscillatory shear indices (OSI) in the aorta than does continuous support. These findings will help to identify the risk of graft failure for pediatric patients with pulsatile and continuous VADs. PMID:24348881

Gia/Mthl5 is an aorta specific GPCR required for Drosophila heart tube morphology and normal pericardial cell positioning.

PubMed

Patel, Meghna V; Zhu, Jun-Yi; Jiang, Zhiping; Richman, Adam; VanBerkum, Mark F A; Han, Zhe

2016-06-01

G-protein signaling is known to be required for cell-cell contacts during the development of the Drosophila dorsal vessel. However, the identity of the G protein-coupled receptor (GPCR) that regulates this signaling pathway activity is unknown. Here we describe the identification of a novel cardiac specific GPCR, called Gia, for "GPCR in aorta". Gia is the only heart-specific GPCR identified in Drosophila to date and it is specifically expressed in cardioblasts that fuse at the dorsal midline to become the aorta. Gia is the only Drosophila gene so far identified for which expression is entirely restricted to cells of the aorta. Deletion of Gia led to a broken-hearted phenotype, characterized by pericardial cells dissociated from cardioblasts and abnormal distribution of cell junction proteins. Both phenotypes were similar to those observed in mutants of the heterotrimeric cardiac G proteins. Lack of Gia also led to defects in the alignment and fusion of cardioblasts in the aorta. Gia forms a protein complex with G-αo47A, the alpha subunit of the heterotrimeric cardiac G proteins and interacts genetically with G-αo47A during cardiac morphogenesis. Our study identified Gia as an essential aorta-specific GPCR that functions upstream of cardiac heterotrimeric G proteins and is required for morphological integrity of the aorta during heart tube formation. These studies lead to a redefinition of the bro phenotype, to encompass morphological integrity of the heart tube as well as cardioblast-pericardial cell spatial interactions. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparing five simple vascular storage protocols.

PubMed

van Doormaal, Tristan P C; Sluijs, Jurren H; Vink, Aryan; Tulleken, Cornelis A F; van der Zwan, Albert

2014-11-01

We aim to find a storage protocol for vessels that preserves their dimensional, histologic, and mechanical characteristics to facilitate reproducible anastomosis experiments and microsurgical training with constant quality. We compared stored rabbit aortas, harvested in a slaughterhouse, using five different protocols with fresh controls. Aortas were preserved for 125 d in (1) NaCl 0.9% at -18°C, (2) Roswell Park Memorial Institute 1640 90% with 10% dimethyl sulfoxide (RPMI/DMSO) at -18°C, (3) RPMI/DMSO at -70°C, (4) glycerol 85% at 4°C, and (5) glycerol in stepwise increased concentrations until 85% at 4°C. After preservation, we measured vessel diameter, wall thickness, and Young's Modulus indicating stiffness. Neurosurgeons compared stored vessels with fresh vessels, blinded for preservation subgroup. We performed histologic assessment blinded for preservation subgroup. Fresh rabbit aortas showed a mean diameter of 2.65 ± 0.14 mm, a mean wall thickness of 126 ± 22 μm, and a Young's Modulus of 11.4 ± 2.4 N/mm(2). NaCl 0.9%-preserved aortas showed a significantly increased vessel diameter and decreased stiffness. RPMI/DMSO-preserved aortas showed no significant differences from fresh aortas in dimensions and mechanical characteristics. Glycerol-preserved tissue showed a significant increase in wall thickness, a related significant decrease in diameter, and increase in stiffness. Neurosurgeons regarded RPMI/DMSO tissue as most comparable with fresh tissue. Histologic assessment revealed no differences between the different protocols and fresh control group. Storage of rabbit aortas in RPMI/DMSO most adequately preserves their dimensional and mechanical properties. Copyright © 2014 Elsevier Inc. All rights reserved.

Correlation of laser-Doppler-velocity measurements and endothelial cell shape in a stenosed dog aorta.

PubMed

Liepsch, D W; Levesque, M; Nerem, R M; Moravec, S T

1988-01-01

Laser-Doppler-velocity measurements were carried out in an elastic 1:1 true-to-scale silicone rubber model of a dog aorta with stenosis. The model was constructed from a cast of a severely stenosed dog aorta (71% of its area). The stenosis in the dog aorta was prepared by wrapping a cotton band around the aorta. This band was tightened until the presence of a thrill or a bruit was felt distal to the band. Twelve weeks later the animal was sacrificed and a cast was prepared from the aorta. From this vascular cast, the cross-sectional area was calculated. Endothelial cell geometry and orientation was studied using computerized analysis to determine the cell area and shape index. An elastic silicone rubber model was prepared from the cast to measure the velocity profiles and to estimate the local wall shear stress. Velocity measurements were done at steady and pulsatile flow using a Newtonian aqueous-glycerol solution and a non-Newtonian blood-like fluid. From those velocity measurements the velocity gradients near the wall were determined and the shear stress calculated. The flow distal to the stenosis separates from the wall at physiological conditions. The endothelial cells are smaller and more elongated in the throat; distal to the stenosis they are larger and rounder. The shape index distribution along the stenosed aorta is correlated with the level of wall shear stress. It is shown that even low changes in the wall shear stress have an influence on the orientation of the endothelial cells.

Associations between a Genetic Risk Score for Clinical CAD and Early Stage Lesions in the Coronary Artery and the Aorta.

PubMed

Salfati, Elias L; Herrington, David M; Assimes, Themistocles L

2016-01-01

The correlation between the extent of fatty streaks, more advanced atherosclerotic lesions, and community rates of coronary artery disease (CAD) is substantially higher for the coronary artery compared to the aorta. We sought to determine whether a genetic basis contributes to these differences. We conducted a cluster analysis of 6 subclinical atherosclerosis phenotypes documented in 564 white participants of the Pathobiological Determinants of Atherosclerosis in Youth study including the extent of fatty streaks and raised lesions in the coronary artery (CF and CR), thoracic aorta (TF and TR), and abdominal aorta (AF and AR) followed by a genetic association analysis of the same phenotypes. Our cluster analysis grouped all raised lesions and fatty streaks in the coronary into one cluster (CF, CR, TR, and AR) and the fatty streaks in the aorta into a second cluster (TF and AF). We found a genetic risk score of high-risk alleles at 57 susceptibility loci for CAD to be variably associated with the phenotypes in the first cluster (OR: 1.30 p = 0.009 for being in top quartile of degree of involvement of CF, 1.34 p = 0.005 for CR, 1.25: p = 0.11 for TR, and 1.19 p = 0.08 for AR) but not at all with the phenotypes in the second cluster (OR: 1.01, p = 0.95 for TF and 0.98, p = 0.82 for AF). The genetic determinants of fatty streaks in the aorta do not appear to overlap substantially with the genetic determinants of fatty streaks in the coronary as well as raised lesions in both the coronary and the aorta. These findings may explain why a larger fraction of fatty streaks in the aorta are less likely to progress to raised lesions compared to the coronary artery.

Associations between a Genetic Risk Score for Clinical CAD and Early Stage Lesions in the Coronary Artery and the Aorta

PubMed Central

Herrington, David M.

2016-01-01

Objective The correlation between the extent of fatty streaks, more advanced atherosclerotic lesions, and community rates of coronary artery disease (CAD) is substantially higher for the coronary artery compared to the aorta. We sought to determine whether a genetic basis contributes to these differences. Approach and Results We conducted a cluster analysis of 6 subclinical atherosclerosis phenotypes documented in 564 white participants of the Pathobiological Determinants of Atherosclerosis in Youth study including the extent of fatty streaks and raised lesions in the coronary artery (CF and CR), thoracic aorta (TF and TR), and abdominal aorta (AF and AR) followed by a genetic association analysis of the same phenotypes. Our cluster analysis grouped all raised lesions and fatty streaks in the coronary into one cluster (CF, CR, TR, and AR) and the fatty streaks in the aorta into a second cluster (TF and AF). We found a genetic risk score of high-risk alleles at 57 susceptibility loci for CAD to be variably associated with the phenotypes in the first cluster (OR: 1.30 p = 0.009 for being in top quartile of degree of involvement of CF, 1.34 p = 0.005 for CR, 1.25: p = 0.11 for TR, and 1.19 p = 0.08 for AR) but not at all with the phenotypes in the second cluster (OR: 1.01, p = 0.95 for TF and 0.98, p = 0.82 for AF). Conclusions The genetic determinants of fatty streaks in the aorta do not appear to overlap substantially with the genetic determinants of fatty streaks in the coronary as well as raised lesions in both the coronary and the aorta. These findings may explain why a larger fraction of fatty streaks in the aorta are less likely to progress to raised lesions compared to the coronary artery. PMID:27861582

Cilostazol enhances atorvastatin-induced vasodilation of female rat aorta during aging.

PubMed

Nurullahoğlu-Atalık, K E; Kutlu, S; Solak, H; Koca, R Özen

2017-09-01

Statins have cholesterol-independent effects including an increased vascular nitric oxide activity and are commonly used by patients with cardiovascular disease. Such patients frequently have cardiovascular diseases, which may be treated with cilostazol, a platelet aggregation inhibitor. This study was designed to investigate whether combined use of cilostazol would increase the inhibitory effect of statin on vascular smooth muscle and how maturation would affect these responses. Female Wistar rats, aged 3-4 months (young) and 14-15 months (adult), were sacrificed by cervical dislocation and the thoracic aorta was dissected and cut into 3- to 4-mm-long rings. The rings were mounted under a resting tension of 1 g in a 20-ml organ bath filled with Krebs-Henseleit solution. Rings were precontracted with phenylephrine (10 -6  M), and the presence of endothelium was confirmed with acetylcholine (10 -6  M). Then, the concentration-response curves were obtained for atorvastatin alone (10 -10 to 3 × 10 -4  M; control) and in the presence of cilostazol (10 -6  M) in young and adult rat aortas. This experimental protocol was also carried out in aorta rings, which had been pretreated with N G -nitro-l-arginine methyl ester (l-NAME, 10 -4  M). Atorvastatin induced concentration-dependent relaxations in young and adult rat thoracic aorta rings precontracted with phenylephrine. The pIC 50 value of atorvastatin was significantly decreased in adult rat aortas. In addition, pretreatment of aortas with cilostazol enhanced the potency of atorvastatin in both young and adult aortas. Incubation with l-NAME did not completely eliminate the relaxations to atorvastatin in the presence of cilostazol. These results suggest that combined application of cilostazol with atorvastatin was significantly more potent than atorvastatin alone. Combined drug therapy may be efficacious in delaying the occurrence of cardiovascular events.

6-Gingerol alleviates exaggerated vasoconstriction in diabetic rat aorta through direct vasodilation and nitric oxide generation.

PubMed

Ghareib, Salah A; El-Bassossy, Hany M; Elberry, Ahmed A; Azhar, Ahmad; Watson, Malcolm L; Banjar, Zainy Mohammed

2015-01-01

The aim of the present study is to investigate the effect and potential mechanism of action of 6-gingerol on alterations of vascular reactivity in the isolated aorta from diabetic rats. Male Wistar rats were divided into two experimental groups, control and diabetics. Diabetes was induced by a single intraperitoneal injection of streptozotocin (50 mg kg(-1)), and the rats were left for 10 weeks to develop vascular complications. The effect of in vitro incubation with 6-gingerol (0.3-3 μM) on the vasoconstrictor response of the isolated diabetic aortae to phenylephrine and the vasodilator response to acetylcholine was examined. Effect of 6-gingerol was also examined on aortae incubated with methylglyoxal as an advanced glycation end product (AGE). To investigate the mechanism of action of 6-gingerol, the nitric oxide synthase inhibitor Nω-nitro-l-arginine methyl ester hydrochloride (100 μM), guanylate cyclase inhibitor methylene blue (5 μM), calcium-activated potassium channel blocker tetraethylammonium chloride (10 mM), and cyclooxygenase inhibitor indomethacin (5 μM) were added 30 minutes before assessing the direct vasorelaxant effect of 6-gingerol. Moreover, in vitro effects of 6-gingerol on NO release and the effect of 6-gingerol on AGE production were examined. Results showed that incubation of aortae with 6-gingerol (0.3-10 μM) alleviated the exaggerated vasoconstriction of diabetic aortae to phenylephrine in a concentration-dependent manner with no significant effect on the impaired relaxatory response to acetylcholine. Similar results were seen in the aortae exposed to methylglyoxal. In addition, 6-gingerol induced a direct vasodilation effect that was significantly inhibited by Nω-nitro-l-arginine methyl ester hydrochloride and methylene blue. Furthermore, 6-gingerol stimulated aortic NO generation but had no effect on AGE formation. In conclusion, 6-gingerol ameliorates enhanced vascular contraction in diabetic aortae, which may be partially attributed to its ability to increase the production of NO and stimulation of cyclic guanosine monophosphate.

6-Gingerol alleviates exaggerated vasoconstriction in diabetic rat aorta through direct vasodilation and nitric oxide generation

PubMed Central

Ghareib, Salah A; El-Bassossy, Hany M; Elberry, Ahmed A; Azhar, Ahmad; Watson, Malcolm L; Banjar, Zainy Mohammed

2015-01-01

The aim of the present study is to investigate the effect and potential mechanism of action of 6-gingerol on alterations of vascular reactivity in the isolated aorta from diabetic rats. Male Wistar rats were divided into two experimental groups, control and diabetics. Diabetes was induced by a single intraperitoneal injection of streptozotocin (50 mg kg−1), and the rats were left for 10 weeks to develop vascular complications. The effect of in vitro incubation with 6-gingerol (0.3–3 μM) on the vasoconstrictor response of the isolated diabetic aortae to phenylephrine and the vasodilator response to acetylcholine was examined. Effect of 6-gingerol was also examined on aortae incubated with methylglyoxal as an advanced glycation end product (AGE). To investigate the mechanism of action of 6-gingerol, the nitric oxide synthase inhibitor Nω-nitro-l-arginine methyl ester hydrochloride (100 μM), guanylate cyclase inhibitor methylene blue (5 μM), calcium-activated potassium channel blocker tetraethylammonium chloride (10 mM), and cyclooxygenase inhibitor indomethacin (5 μM) were added 30 minutes before assessing the direct vasorelaxant effect of 6-gingerol. Moreover, in vitro effects of 6-gingerol on NO release and the effect of 6-gingerol on AGE production were examined. Results showed that incubation of aortae with 6-gingerol (0.3–10 μM) alleviated the exaggerated vasoconstriction of diabetic aortae to phenylephrine in a concentration-dependent manner with no significant effect on the impaired relaxatory response to acetylcholine. Similar results were seen in the aortae exposed to methylglyoxal. In addition, 6-gingerol induced a direct vasodilation effect that was significantly inhibited by Nω-nitro-l-arginine methyl ester hydrochloride and methylene blue. Furthermore, 6-gingerol stimulated aortic NO generation but had no effect on AGE formation. In conclusion, 6-gingerol ameliorates enhanced vascular contraction in diabetic aortae, which may be partially attributed to its ability to increase the production of NO and stimulation of cyclic guanosine monophosphate. PMID:26609223

Antioxidant and triglyceride-lowering effects of vitamin E associated with the prevention of abnormalities in the reactivity and morphology of aorta from streptozotocin-diabetic rats. Antioxidants in Diabetes-Induced Complications (ADIC) Study Group.

PubMed

Karasu, C; Ozansoy, G; Bozkurt, O; Erdoğan, D; Omeroğlu, S

1997-08-01

In this study, we evaluated the effects of vitamin E on the vascular reactivity and structure of thoracic aorta from streptozotocin (STZ)-diabetic rats. Plasma glucose, cholesterol, and triglyceride concentrations in rats were increased markedly by STZ-diabetes. The thiobarbituric acid (TBA) reactivity level as an index of lipid peroxidation was higher in both plasma and aorta of STZ-diabetic rats compared with controls. The rings of thoracic aorta with or without endothelium were mounted in organ chambers for measurement of isometric tension and were contracted by a single dose (10-5 mol/L) and then cumulative doses of noradrenaline ([NA] 10(-9) to 10(-5) mol/L). Pretreatment with methylene blue (MB) or removal of the endothelium resulted in a similar degree of enhancement in NA-induced contraction of control rings. STZ-diabetes increased the fast and slow components of NA-induced contraction in all experiments. The maximal contractile response of aorta to NA was also augmented by STZ-diabetes, whereas the sensitivity (pD2) remained unaltered. STZ-diabetes resulted in significant increases in the maximum contractile response and sensitivity of aorta to KCl. STZ-diabetic rats showed a significant reduction in the percentage of endothelial response (PER). A group of diabetic rats was treated from the time of diabetes induction with a 0.5% dietary supplement of vitamin E. Vitamin E supplementation of STZ-diabetic rats eliminated accumulation of lipid peroxides and returned plasma triglycerides toward normal levels. Diabetes-induced abnormal contractility and endothelial dysfunction were significantly but not completely prevented by vitamin E treatment. The endothelium-independent relaxation response to sodium nitroprusside (SNP) was not affected by diabetes or vitamin E treatment. Electron microscopic examination of thoracic aorta revealed that normal tissue organization was disrupted in STZ-diabetic rats, and that vitamin E treatment can protect the morphological integrity of aorta against STZ-diabetes. The results suggest the following: (1) The increased triglycerides/lipid peroxides may be an important reason for morphological or functional disruption of endothelium and enhanced activation of contractile mechanisms of vascular smooth muscle in STZ-diabetic rats. Both contribute to an increased responsiveness of diabetic aorta to vasoconstrictor agents. (2) Vitamin E treatment of STZ-diabetic rats can prevent the development of abnormal contractility and structure and endothelial dysfunction in aorta. (3) The triglyceride- and/or lipid peroxidation-lowering effect of vitamin E may be crucial for the protective effect of this vitamin on the vasculature.

Effects of age and cardiovascular risk factors on (18)F-FDG PET/CT quantification of atherosclerosis in the aorta and peripheral arteries.

PubMed

Pasha, Ahmed K; Moghbel, Mateen; Saboury, Babak; Gharavi, Mohammed H; Blomberg, Björn A; Torigian, Drew A; Kwee, Thomas C; Basu, Sandip; Mohler Iii, Emile R; Alavi, Abass

2015-01-01

To quantify fluorine-18 fluorodeoxyglucose ((18)F-FDG) uptake in the aorta and peripheral arteries and assess the variation of (18)F-FDG uptake with age and cardiovascular risk factors. The subject population of this retrospective study comprises melanoma patients who underwent whole-body (18)F-FDG PET/CT scans. The patients' medical records were examined for cardiovascular risk factors and for a history of coronary artery disease or peripheral artery disease. Fluorine-18-FDG uptake in the peripheral arteries (iliac and femoral) and aorta was semi-quantified as a weighted-average mean standardized uptake value (wA-SUVmean), while background noise was accounted for by measuring mean venous blood pool SUV (V-SUVmean) in the superior vena cava. Atherosclerosis was semi-quantified by the tissue-to-background ratio (TBR) (wA-SUVmean divided by V-SUVmean). A regression model and t-test were used to evaluate the effect of age and location on the degree of atherosclerosis. To assess the effect of cardiovascular risk factors on atherosclerotic burden, the wA-SUVmean of patients with at least one of these risk factors was compared to that of patients without any risk factors. A total of 76 patients (46 men, 30 women; 22-91 years old) were included in this study. The average TBR of the aorta and peripheral arteries were 2.68 and 1.43, respectively, and increased with age in both locations. In regression analysis, the beta coefficients of age for TBR in the aorta and peripheral arteries were 0.55 (P<0.001) and 0.03 (P<0.001), respectively. In all age groups, the TBR of the aorta was significantly greater than that of the peripheral arteries. The Pearson correlation coefficients between the four age groups and the TBR of the aorta and peripheral arteries were 0.83 (P<0.001) and 0.75 (P<0.001), respectively. The wA-SUVmean of patients with cardiovascular risk factors was only significant (P<0.05) in the aorta. An increase in (18)F-FDG uptake was observed in the peripheral arteries and aorta with increasing age. Cardiovascular risk factors were significantly correlated with (18)F-FDG uptake in aorta. The early detection of atherosclerosis with (18)F-FDG PET may allow for the initiation of preventative interventions prior to the manifestation of significant structural abnormalities or symptoms of disease.

Validity of the Water Hammer Formula for Determining Regional Aortic Pulse Wave Velocity: Comparison of One-Point and Two-Point (Foot-to-Foot) Measurements Using a Multisensor Catheter in Human.

PubMed

Hanya, Shizuo

2013-01-01

Lack of high-fidelity simultaneous measurements of pressure and flow velocity in the aorta has impeded the direct validation of the water-hammer formula for estimating regional aortic pulse wave velocity (AO-PWV1) and has restricted the study of the change of beat-to-beat AO-PWV1 under varying physiological conditions in man. Aortic pulse wave velocity was derived using two methods in 15 normotensive subjects: 1) the conventional two-point (foot-to-foot) method (AO-PWV2) and 2) a one-point method (AO-PWV1) in which the pressure velocity-loop (PV-loop) was analyzed based on the water hammer formula using simultaneous measurements of flow velocity (Vm) and pressure (Pm) at the same site in the proximal aorta using a multisensor catheter. AO-PWV1 was calculated from the slope of the linear regression line between Pm and Vm where wave reflection (Pb) was at a minimum in early systole in the PV-loop using the water hammer formula, PWV1 = (Pm/Vm)/ρ, where ρ is the blood density. AO-PWV2 was calculated using the conventional two-point measurement method as the distance/traveling time of the wave between 2 sites for measuring P in the proximal aorta. Beat-to-beat alterations of AO-PWV1 in relationship to aortic pressure and linearity of the initial part of the PV-loop during a Valsalva maneuver were also assessed in one subject. The initial part of the loop became steeper in association with the beat-to-beat increase in diastolic pressure in phase 4 during the Valsalva maneuver. The linearity of the initial part of the PV-loop was maintained consistently during the maneuver. Flow velocity vs. pressure in the proximal aorta was highly linear during early systole, with Pearson's coefficients ranging from 0.9954 to 0.9998. The average values of AO-PWV1 and AO-PWV2 were 6.3 ± 1.2 and 6.7 ± 1.3 m/s, respectively. The regression line of AO-PWV1 on AO-PWV2 was y = 0.95x + 0.68 (r = 0.93, p <0.001). This study concluded that the water-hammer formula (one-point method) provides a reliable and conventional estimate of beat-to-beat aortic regional pulse wave velocity consistently regardless of the changes in physiological states in human clinically. (English Translation of J Jpn Coll Angiol 2011; 51: 215-221).

Validity of the Water Hammer Formula for Determining Regional Aortic Pulse Wave Velocity: Comparison of One-Point and Two-Point (Foot-to-Foot) Measurements Using a Multisensor Catheter in Human

PubMed Central

2013-01-01

Background: Lack of high-fidelity simultaneous measurements of pressure and flow velocity in the aorta has impeded the direct validation of the water-hammer formula for estimating regional aortic pulse wave velocity (AO-PWV1) and has restricted the study of the change of beat-to-beat AO-PWV1 under varying physiological conditions in man. Methods: Aortic pulse wave velocity was derived using two methods in 15 normotensive subjects: 1) the conventional two-point (foot-to-foot) method (AO-PWV2) and 2) a one-point method (AO-PWV1) in which the pressure velocity-loop (PV-loop) was analyzed based on the water hammer formula using simultaneous measurements of flow velocity (Vm) and pressure (Pm) at the same site in the proximal aorta using a multisensor catheter. AO-PWV1 was calculated from the slope of the linear regression line between Pm and Vm where wave reflection (Pb) was at a minimum in early systole in the PV-loop using the water hammer formula, PWV1 = (Pm/Vm)/ρ, where ρ is the blood density. AO-PWV2 was calculated using the conventional two-point measurement method as the distance/traveling time of the wave between 2 sites for measuring P in the proximal aorta. Beat-to-beat alterations of AO-PWV1 in relationship to aortic pressure and linearity of the initial part of the PV-loop during a Valsalva maneuver were also assessed in one subject. Results: The initial part of the loop became steeper in association with the beat-to-beat increase in diastolic pressure in phase 4 during the Valsalva maneuver. The linearity of the initial part of the PV-loop was maintained consistently during the maneuver. Flow velocity vs. pressure in the proximal aorta was highly linear during early systole, with Pearson’s coefficients ranging from 0.9954 to 0.9998. The average values of AO-PWV1 and AO-PWV2 were 6.3 ± 1.2 and 6.7 ± 1.3 m/s, respectively. The regression line of AO-PWV1 on AO-PWV2 was y = 0.95x + 0.68 (r = 0.93, p <0.001). Conclusion: This study concluded that the water-hammer formula (one-point method) provides a reliable and conventional estimate of beat-to-beat aortic regional pulse wave velocity consistently regardless of the changes in physiological states in human clinically. (*English Translation of J Jpn Coll Angiol 2011; 51: 215-221) PMID:23825494

The presence of both horseshoe and a supernumerary kidney associated with coarctation of aorta.

PubMed

Unal, M; Erem, C; Serçe, K; Tuncer, C; Bostan, M; Gökçe, M

1995-01-01

Congenital urinary malformations associated with congenital heart disease are very rare. We present a case of horseshoe and supernumerary kidney associated with coarctation of aorta diagnosed by a combination of techniques of teleradiography, aortography, intravenous pyelography; ultrasonography, magnetic resonance imaging, and Dimercapto Succinic Acid (DMSA) and Diethylene Triamine Pentacetate (DTPA) imaging. This case represents the first reported instance of horseshoe and supernumerary kidney associated with coarctation of aorta.

Case report of an unusual combination of purulent pericarditis and false aneurysm of the ascending aorta.

PubMed

Meier, David; Kirsch, Matthias; Qanadli, Salah Dine; Muller, Olivier; Fishman, Daniel; Trana, Catalina

2018-01-29

Purulent pericarditis is an uncommon entity, which is, in very rare cases, associated to infection of the aorta. We present the case of a 42-year-old male patient, who was admitted to hospital complaining of tiredness, diarrhea and leg edema. Clinical examination revealed a hypotensive and obviously shocked patient. He was ultimately diagnosed with a rare combination of purulent pericarditis followed by false aneurysm of the ascending aorta. He was successfully treated by surgical pericardial drainage, replacement of the ascending aorta and antibiotics. Mycotic aneurysms can rarely be associated with purulent pericarditis. Our literature review shows that there are two mechanisms explaining this association and that in most of the published cases infective endocarditis could not be demonstrated.

Acute Left Arm Ischemia Associated with Floating Thrombus in the Proximal Descending Aorta: Combined Endovascular and Surgical Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fanelli, F., E-mail: fabrizio.fanelli@uniroma1.it; Gazzetti, M.; Boatta, E.

Free floating thrombus in the proximal descending aorta is an uncommon and dangerous condition that can be associated with acute peripheral embolization. The few cases described were solved with surgical and/or medical therapy. We report the case of a patient with acute left arm ischemia secondary to the presence of floating thrombus in the proximal descending aorta extending into the left subclavian artery, solved with combined endovascular and surgical therapy. Treatment was successfully performed with thrombembolectomy combined with temporary deployment, into the descending aorta, of a Wallstent in a 'basket-fashion' to avoid distal embolization secondary to thrombus fragmentation. At 1more » year follow-up the patient remained symptom-free.« less

Bioactive antibiotic levels in the human aorta.

PubMed

Mutch, D; Richards, G; Brown, R A; Mulder, D S

1982-12-01

A new bioassay was used to determine the level of active antibiotic within the aortic wall in 24 patients undergoing elective aortic surgery involving prosthetic grafts. The patients were divided into three groups and received either cefazolin, clindamycin, or cefoxitin intravenously at the induction of general anesthesia. Cefazolin and cefoxitin attained satisfactory tissue levels. Clindamycin did not reach therapeutic levels in the aortic wall. Blood levels did not correlate well with tissue levels.

Epigenetic control of vascular smooth muscle cells in Marfan and non-Marfan thoracic aortic aneurysms

PubMed Central

Gomez, Delphine; Coyet, Aurélie; Ollivier, Véronique; Jeunemaitre, Xavier; Jondeau, Guillaume; Michel, Jean-Baptiste; Vranckx, Roger

2011-01-01

Aims Human thoracic aortic aneurysms (TAAs) are characterized by extracellular matrix breakdown associated with progressive smooth muscle cell (SMC) rarefaction. These features are present in all types of TAA: monogenic forms [mainly Marfan syndrome (MFS)], forms associated with bicuspid aortic valve (BAV), and degenerative forms. Initially described in a mouse model of MFS, the transforming growth factor-β1 (TGF-β1)/Smad2 signalling pathway is now assumed to play a role in TAA of various aetiologies. However, the relation between the aetiological diversity and the common cell phenotype with respect to TGF-β signalling remains unexplained. Methods and results This study was performed on human aortic samples, including TAA [MFS, n = 14; BAV, n = 15; and degenerative, n = 19] and normal aortas (n = 10) from which tissue extracts and human SMCs and fibroblasts were obtained. We show that all types of TAA share a complex dysregulation of Smad2 signalling, independent of TGF-β1 in TAA-derived SMCs (pharmacological study, qPCR). The Smad2 dysregulation is characterized by an SMC-specific, heritable activation and overexpression of Smad2, compared with normal aortas. The cell specificity and heritability of this overexpression strongly suggest the implication of epigenetic control of Smad2 expression. By chromatin immunoprecipitation, we demonstrate that the increases in H3K9/14 acetylation and H3K4 methylation are involved in Smad2 overexpression in TAA, in a cell-specific and transcription start site-specific manner. Conclusion Our results demonstrate the heritability, the cell specificity, and the independence with regard to TGF-β1 and genetic backgrounds of the Smad2 dysregulation in human thoracic aneurysms and the involvement of epigenetic mechanisms regulating histone marks in this process. PMID:20829218

Embolic capture with updated intra-aortic filter during coronary artery bypass grafting and transaortic transcatheter aortic valve implantation: first-in-human experience.

PubMed

Ye, Jian; Webb, John G

2014-12-01

We report our first-in-human clinical experience in the use of the new version of the EMBOL-X intra-aortic filter (Edwards Lifesciences Corporation, Irvine, Calif) to capture embolic material during transaortic transcatheter aortic valve implantation and cardiac surgery. Five patients were enrolled into the first-in-human clinical assessment of the new version of the EMBOL-X intra-aortic filter. Three patients underwent coronary artery bypass grafting, and 2 patients underwent transaortic transcatheter aortic valve implantation. During coronary artery bypass grafting, the filter was deployed before clamping of the aorta and removal of the aortic clamp. In contrast, the filter was deployed before aortic puncture for transaortic transcatheter aortic valve implantation and kept in the aorta throughout the entire procedure. The filter introducer sheath and filter were easily placed and removed without difficulty. There were no complications related to the use of the filter. Postoperative examination of the retrieved filters revealed the presence of multiple microemboli in the filters from all 5 cases. Histologic study revealed various kinds of tissue and thrombus. This first-in-human clinical experience has demonstrated the safety and feasibility of using the new version of the EMBOL-X intra-aortic filter during either cardiac surgery or transaortic transcatheter aortic valve implantation. We believe that the combination of the transaortic approach without aortic arch manipulation and the use of the EMBOL-X filter with a high capture rate is a promising strategy to reduce the incidence of embolic complications during transcatheter aortic valve implantation. Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Aortic aneurysm repair - endovascular

MedlinePlus

EVAR; Endovascular aneurysm repair - aorta; AAA repair - endovascular; Repair - aortic aneurysm - endovascular ... to guide the stent graft up into your aorta, to where the aneurysm is located. Next open ...

Coarctation of the aorta

MedlinePlus

... brain Early development of coronary artery disease (CAD) Endocarditis (infection in the heart) Heart failure Hoarseness Kidney ... include: Continued or repeated narrowing of the aorta Endocarditis High blood pressure

Thoracic aortic aneurysm

MedlinePlus

... the part of the body's largest artery (the aorta) that passes through the chest. ... Marfan or Ehlers-Danlos syndrome Inflammation of the aorta Injury from falls or motor vehicle accidents Syphilis

Relationship Between Proximal Aorta Morphology and Progression Rate of Aortic Stenosis.

PubMed

Capoulade, Romain; Teoh, Jonathan G; Bartko, Philipp E; Teo, Eliza; Scholtz, Jan-Erik; Tastet, Lionel; Shen, Mylene; Mihos, Christos G; Park, Yong H; Garcia, Julio; Larose, Eric; Isselbacher, Eric M; Sundt, Thoralf M; MacGillivray, Thomas E; Melnitchouk, Serguei; Ghoshhajra, Brian B; Pibarot, Philippe; Hung, Judy

2018-05-01

The aim of this study was to examine the association between abnormal morphology of the proximal aorta and aortic stenosis (AS) progression rate. The main hypothesis was that morphologic changes of the proximal aorta, such as effacement of the sinotubular junction (STJ), result in increased biomechanical stresses and contribute to calcification and progression of AS. Between 2010 and 2012, 426 patients with mild to moderate AS were included in this study. Proximal aortic dimensions were measured at three different levels (i.e., sinus of Valsalva, STJ, and ascending aorta), and sinuses of Valsalva/STJ and ascending aorta/STJ ratios were used to determine degree of aortic deformity. AS progression rate was assessed by annualized increase in mean gradient (median follow-up time, 3.1 years; interquartile range, 2.6-3.9 years). The degree of aortic flow turbulence was examined in 18 matched patients with and without STJ effacement using cardiac magnetic resonance phase-contrast imaging. Patients' mean age was 71 ± 13 years, and 64% were men. Patients with low ratios had greater AS progression (P < .05). After comprehensive adjustment, sinuses of Valsalva/STJ (P = .025) and ascending aorta/STJ (P = .027) ratios were independently associated with greater AS progression rate. Compared with patients without STJ effacement, those with effacement of the STJ had higher degrees of aortic flow turbulence (24.4% vs 17.2%, P = .038). Effacement of the STJ is independently associated with greater AS progression, regardless of arterial hemodynamics, aortic valve phenotype, or baseline AS severity. Patients with abnormal proximal aortic geometry had disturbed aortic flow patterns. These findings suggest an interrelation between proximal aorta morphology and stenosis progression. Copyright © 2017 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

Differential effects of eNOS uncoupling on conduit and small arteries in GTP-cyclohydrolase I-deficient hph-1 mice.

PubMed

d'Uscio, Livius V; Smith, Leslie A; Katusic, Zvonimir S

2011-12-01

In the present study, we used the hph-1 mouse, which displays GTP-cyclohydrolase I (GTPCH I) deficiency, to test the hypothesis that loss of tetrahydrobiopterin (BH(4)) in conduit and small arteries activates compensatory mechanisms designed to protect vascular wall from oxidative stress induced by uncoupling of endothelial nitric oxide synthase (eNOS). Both GTPCH I activity and BH(4) levels were reduced in the aortas and small mesenteric arteries of hph-1 mice. However, the BH(4)-to-7,8-dihydrobiopterin ratio was significantly reduced only in hph-1 aortas. Furthermore, superoxide anion and 3-nitrotyrosine production were significantly enhanced in aortas but not in small mesenteric arteries of hph-1 mice. In contrast to the aorta, protein expression of copper- and zinc-containing superoxide dismutase (CuZnSOD) was significantly increased in small mesenteric arteries of hph-1 mice. Protein expression of catalase was increased in both aortas and small mesenteric arteries of hph-1 mice. Further analysis of endothelial nitric oxide synthase (eNOS)/cyclic guanosine monophosphate (cGMP) signaling demonstrated that protein expression of phosphorylated Ser(1177)-eNOS as well as basal cGMP levels and hydrogen peroxide was increased in hph-1 aortas. Increased production of hydrogen peroxide in hph-1 mice aortas appears to be the most likely mechanism responsible for phosphorylation of eNOS and elevation of cGMP. In contrast, upregulation of CuZnSOD and catalase in resistance arteries is sufficient to protect vascular tissue from increased production of reactive oxygen species generated by uncoupling of eNOS. The results of our study suggest that anatomical origin determines the ability of vessel wall to cope with oxidative stress induced by uncoupling of eNOS.

Detection of thoracic vascular structures by electrical impedance tomography: a systematic assessment of prominence peak analysis of impedance changes.

PubMed

Wodack, K H; Buehler, S; Nishimoto, S A; Graessler, M F; Behem, C R; Waldmann, A D; Mueller, B; Böhm, S H; Kaniusas, E; Thürk, F; Maerz, A; Trepte, C J C; Reuter, D A

2018-02-28

Electrical impedance tomography (EIT) is a non-invasive and radiation-free bedside monitoring technology, primarily used to monitor lung function. First experimental data shows that the descending aorta can be detected at different thoracic heights and might allow the assessment of central hemodynamics, i.e. stroke volume and pulse transit time. First, the feasibility of localizing small non-conductive objects within a saline phantom model was evaluated. Second, this result was utilized for the detection of the aorta by EIT in ten anesthetized pigs with comparison to thoracic computer tomography (CT). Two EIT belts were placed at different thoracic positions and a bolus of hypertonic saline (10 ml, 20%) was administered into the ascending aorta while EIT data were recorded. EIT images were reconstructed using the GREIT model, based on the individual's thoracic contours. The resulting EIT images were analyzed pixel by pixel to identify the aortic pixel, in which the bolus caused the highest transient impedance peak in time. In the phantom, small objects could be located at each position with a maximal deviation of 0.71 cm. In vivo, no significant differences between the aorta position measured by EIT and the anatomical aorta location were obtained for both measurement planes if the search was restricted to the dorsal thoracic region of interest (ROIs). It is possible to detect the descending aorta at different thoracic levels by EIT using an intra-aortic bolus of hypertonic saline. No significant differences in the position of the descending aorta on EIT images compared to CT images were obtained for both EIT belts.

ECG-triggered high-pitch CT for simultaneous assessment of the aorta and coronary arteries.

PubMed

Hachulla, Anne-Lise; Ronot, Maxime; Noble, Stéphane; Becker, Christoph D; Montet, Xavier; Vallée, Jean-Paul

2016-01-01

To study the image quality of ECG-gated-computed tomography (CT) acquisition with a high-pitch CT imaging for the exploration of both the aorta and coronary arteries. Eighty-four patients underwent high-pitch ECG-gated aortic CT without β-blockers with iterative reconstruction algorithms. Contrast-to-noise ratio (CNR) between vessels and adjacent perivascular fat tissue were calculated on the aorta and the coronary arteries. Dose-length-products (DLP) were recorded. Two blinded readers graded image quality of the aorta and the coronary arteries on a 3-point scale. Coronary artery stenoses were compared with coronary angiograms in 24 patients. Kappa values were calculated. High-pitch acquisition resulted in a mean DLP of 234 ± 93 mGy cm(4.2 mSv) for an acquisition of the entire aorta, (mean 73 ± 16 bpm). CNR for ascending aorta was 10.6 ± 4 and CNR for coronary arteries was 9.85 ± 4.1. Image quality was excellent in 79/84 patients (94%), and excellent or moderate but diagnostic in 1087/1127 coronary artery segments (96%). 74 significant stenoses were observed, and 38/40 significant stenoses were confirmed by coronary angiography (K = 0.91, Sensitivity = 0.97, Specificity = 0.98). High-pitch ECG-gated aortic CT with iterative reconstructions allows an accurate exploration of both aorta and coronary arteries during the same acquisition, with limited dose deposition, despite the lack of β-blockers and relatively high heart rate. Radiologists need to be aware of the necessity to analyze and report coronary artery disease in aortic examination. Copyright © 2016 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

Study of the Blood Supply Fraction of the Ascending Aorta and Its Effect in Diagnosing Early Ascending Aortic Atherosclerosis.

PubMed

Wang, Kun; Cao, Tiesheng; Zhao, Lianbi; Yang, Yong; Feng, Yang; Duan, Yunyou; Yuan, Lijun; Xing, Changyang; Ren, Huari

2016-03-01

To investigate the capacity of blood storage of certain large arteries during diastole, we first studied the ascending aorta by echocardiography. The concept of the blood supply fraction of the ascending aorta was then introduced to evaluate elastic retraction of the ascending aortic wall and determine its role in diagnosing early atherosclerosis of the ascending aorta. First, we enrolled 120 healthy volunteers and divided them into 3 groups according to age: 20 to 35 years (B1 group), 36 to 50 years (B2 group), and 51 to 65 years (B3 group); there were 40 volunteers in each group. We used echocardiography to measure the blood supply fraction in each volunteer and compared the results for each group. Then we enrolled 40 patients (51-65 years) with early atherosclerosis of the ascending aorta, measured the blood supply fraction of each, and compared the results with the B3 group. The mean blood supply fractions ± SD in the B1, B2, and B3 groups were 21.75% ± 1.53%, 20.76% ± 1.62%, and 18.44% ± 1.19%, respectively. The fraction in the B3 group was significantly lower than those in the B1 and B2 groups (P < .01). The fraction in the patients with early atherosclerosis was 14.92% ± 1.01%, which was obviously lower than that in the B3 group (P < .01). The blood supply fraction of the ascending aorta decreases with age, and it could be used as a parameter for diagnosis of early atherosclerosis of the ascending aorta. © 2016 by the American Institute of Ultrasound in Medicine.

Complications at the Proximal Landing Zone of Endovascular Stent Grafts Deployed in Surgically Replaced Ascending Aorta.

PubMed

Kotha, Vamshi K; Herget, Eric J; Appoo, Jehangir J

2016-11-01

The ascending aorta, with its hostile angulations and forces, is the next frontier in the evolution of endovascular surgery. Type II hybrid arch repair, involving surgical replacement of the ascending aorta, arch debranching, and stent graft deployment in the ascending aortic graft, offers an opportunity to study the behavior of an endovascular prosthesis in the ascending aorta. We report complications seen at the proximal landing zone after type II hybrid arch repair. A dedicated imaging protocol was used to monitor 20 consecutive patients who underwent type II hybrid arch repair at a single center from June 2009 to July 2014. Mean age was 66 years (range, 47 to 82 years). Mean imaging follow-up was 34 months (range, 12 to 64 months). There was 1 operative death (5%). Bird beaking (>5 mm of nonapposition) of the stent graft at the proximal landing zone occurred in 12 patients, and >20 mm of bird beaking occurred in 7 patients. Proximal landing zone complications occurred in 4 patients (20%), comprising 2 type Ia endoleaks, 1 graft migration, and 1 graft infolding detected on postoperative days 4, 11, 5, and 755, respectively. Three patients underwent endovascular reintervention for proximal landing zone complications. There were no late deaths. Thoracic aortic stent grafts may be prone to proximal landing zone complications when deployed in the ascending aorta. Bird beaking is common when endografts are deployed in the Dacron (DuPont, Wilmington, DE) ascending aorta. Angulation issues will likely need to be overcome by stent graft refinement to enable future closed chest approaches to the ascending aorta. Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Natural history of the ascending aorta after aortic valve replacement: risk factor analysis for late aortic complications after aortic valve replacement.

PubMed

Tsutsumi, Koji; Hashizume, Kenichi; Inoue, Yoshito

2016-05-01

The purpose of this study was to clarify the natural history of the ascending aorta and to identify risk factors for late ascending aortic events after first isolated aortic valve replacement (AVR). A total of 287 patients undergoing AVR were enrolled. The patients were categorized into two groups based on the diameter of the ascending aorta at the time of AVR, as determined by computed tomography: Group A (n = 233) was defined as an ascending aortic diameter <40 mm, and Group B (n = 54) was defined as an ascending aortic diameter ≥40 mm. The mean follow-up period was 7.6 years. The baseline diameter of the ascending aorta was 31.4 ± 4.8 mm in Group A and 44.7 ± 4.2 mm in Group B. These values increased to 35.9 ± 7.4 mm in Group A and 50.1 ± 7.3 mm in Group B during the follow-up period (P < 0.001). Ten patients had acute type A aortic dissection (Group A: 1 patient vs. Group B: 9 patients; P < 0.001), and three patients had enlargement of the ascending aorta to ≥55 mm in diameter (Group A: 1 patient vs. Group B: 2 patients). Multivariate analysis revealed that the baseline ascending aortic diameter was the only significant risk factor for developing late ascending aortic events (P < 0.001). AVR alone may not prevent further enlargement of the ascending aorta. An ascending aorta ≥40 mm in diameter at the time of AVR increased the risk of late ascending aortic events.

Racial differences in thoracic aorta atherosclerosis among ischemic stroke patients.

PubMed

Gupta, Vishal; Nanda, Navin C; Yesilbursa, Dilek; Huang, Wen Ying; Gupta, Vijaya; Li, Qing; Gomez, Camilo R

2003-02-01

Atherosclerosis of the thoracic aorta is an independent risk factor for stroke. There is little information on the impact of race in the prevalence of thoracic aorta atherosclerotic plaques among ischemic stroke patients. This study was an attempt to objectively assess the prevalence, thickness, and burden of thoracic aorta atherosclerotic plaques in a large population of ischemic stroke patients and to compare the differences between American blacks and whites. This is a retrospective study of clinical data and transesophageal echocardiography (TEE) of 1553 ischemic stroke patients (664 blacks, 889 whites) over a period of 4.5 years. Atherosclerotic plaque prevalence, thickness, morphology, and burden (sum of maximum thickness in ascending aorta [AA], aortic arch [AO], and descending aorta [DA]) were assessed with TEE. Charts were reviewed for clinical information. Age and sex were similar among blacks and whites. Analyses of clinical data found that blacks had significantly higher hypertension (odds ratio [OR], 2.61; P<0.0001) and diabetes mellitus (OR, 1.99; P<0.0001) and significantly lower coronary artery disease (OR, 0.75; P=0.017) and carotid artery disease (OR, 0.62; P=0.0008) compared with whites. TEE showed that whites had significantly greater plaque prevalence (AA: OR, 1.37; P=0.04; AO: OR, 1.26; P=0.03; DA: OR, 1.39; P=0.002) and plaque burden (blacks, 4.28 mm; whites, 4.97 mm; P=0.007). Whites also had a trend of increased complex plaques and plaques >4 mm thick in all regions of the thoracic aorta. Among ischemic stroke patients, blacks had a lower prevalence of extra cranial atherosclerotic disease even though they had significantly higher hypertension and diabetes mellitus compared with whites. This difference cannot be explained by the existing risk factors in ischemic stroke patients.

Alterations in the lipid metabolism of rat aorta: effects of vitamin a deficiency.

PubMed

Gatica, Laura V; Vega, Verónica A; Zirulnik, Fanny; Oliveros, Liliana B; Gimenez, María S

2006-01-01

Antioxidants are known to reduce cardiovascular disease by reducing the concentration of free radicals in the vessel wall and by preventing the oxidative modification of low-density lipoproteins. The prooxidative effect of a vitamin-A-deficient diet on the aorta has previously been demonstrated by us. In this study, the lipid metabolism in the aorta of rats fed on a vitamin-A-deficient diet was evaluated. Vitamin A deficiency induced a hypolipidemic effect (lower serum triglyceride and cholesterol levels) and a decreased serum paraoxonase 1/arylesterase activity. The concentrations of triglycerides, total cholesterol, free and esterified cholesterol, and phospholipids were increased in the aorta of vitamin-A-deficient rats. The phospholipid compositions showed an increase in phosphatidylcholine (PC), phosphatidylinositol plus phosphatidylserine and phosphatidylethanolamine, a decrease in sphingomyelin, and no change in phosphatidylglycerol. In the aorta, the increase in triglycerides was associated with an increased fatty acid synthesis and mRNA expression of diacylglycerol acyltransferase 1. The increased PC content was attributed to an increased synthesis, as measured by [methyl-(14)C]choline incorporation into PC and high CTP:phosphocholine cytidylyltransferase-alpha mRNA expression. The cholesterol synthesis, evaluated by [1-(14)C]acetate incorporated into cholesterol and mRNA expression of 3-hydroxy-3-methylglutaryl coenzyme A reductase, did not change. The lipoprotein lipase and lectin-like oxidized low-density lipoprotein receptor 1 mRNA expression levels increased in the aorta of vitamin-A-deficient animals. The incorporation of vitamin A into the diet of vitamin-A-deficient rats reverted all the changes observed. These results indicate that a vitamin-A-deficient diet,in addition to having a prooxidative effect, alters the aorta lipid metabolism.

Use of the Abdominal Aortic Tourniquet for Hemorrhage Control

DTIC Science & Technology

2016-06-01

compression to the aorta at the abdominal-pelvic junction to occlude blood flow in the common iliac and inguinal arteries. The target of the compression...circumferential device that utilizes a belt, windlass and pneumatic pressure to compress the aorta . The belt and windlass together greatly increase the...clamping the aorta or fully stopping all blood flow to the pelvis and lower extremities. In essence the AAT™ acts as a valve to figuratively ‘turn the

Combined repair of adult coarctation of the aorta and aortic valvular stenosis.

PubMed

Ivert, T; Busund, R; Avenarius, D; Dahi, P E

2000-06-01

A 57-year-old man with a high-grade aortic stenosis and aortic coarctation was treated with concomitant valve replacement and insertion of a conduit from the ascending aorta to the retrocardiac descending aorta via the left pleura. Because heart failure has been reported shortly after cardiopulmonary bypass using this technique, the conduit was initially clamped until the postrepair haemodynamics was stable. Computed tomography after 14 months verified patency of the shunt.

Palpation Simulator of Beating Aorta for Cardiovascular Surgery Training

NASA Astrophysics Data System (ADS)

Yamamoto, Yasuhiro; Nakao, Megumi; Kuroda, Tomohiro; Oyama, Hiroshi; Komori, Masaru; Matsuda, Tetsuya; Sakaguchi, Genichi; Komeda, Masashi; Takahashi, Takashi

In field of cardiovascular surgeries, palpation of aorta plays important roles in decision of surgical site.This paper develops palpation simulator of aorta based on a finite element based physical model.The proposed model calculates soft tissue deformation according to the affection of inner pressure and the operation of a surgeon.The proposed method is implemented on a prototype with dual PHANToM device.Experimental results confirmed our model achieves real time simulation of the surgical palpation.

Correlation of ascending aorta elasticity and the severity of coronary artery stenosis in hypertensive patients with coronary heart disease assessed by M-mode and tissue Doppler echocardiography.

PubMed

Lu, Qixiu; Liu, Houlin

2015-03-01

The main objective of this study is to investigate the relationship between ascending aorta elasticity and the severity of coronary artery stenosis in essential hypertensive patients with coronary heart disease (CHD) using M-mode and tissue Doppler echocardiography. A total of 184 hypertensive patients with CHD were enrolled. Patients were divided into three groups based on the severity of coronary stenosis measured by coronary arteriography (CAG): slight stenosis (group 1), moderate stenosis (group 2) and serious stenosis (group 3). M-mode and tissue Doppler echocardiography were performed, and elasticity indexes of ascending aorta including stiffness index, distensibility index, and S wave speed of anterior wall were calculated and correlated with the severity of coronary stenosis. Ascending aorta stiffness index was increased, whereas distensibility index and S wave speed of anterior wall were decreased in moderate and severe stenosis groups compared with slight stenosis group (P < 0.01). Elasticity indexes change in a stepwise pattern with the narrowness of coronary artery, and there was a significant correlation between aortic elasticity and severity of coronary artery by Pearson correlation analysis (P < 0.01). Elasticity indexes of ascending aorta correlate well with severity of coronary stenosis. Elasticity indexes of ascending aorta can serve as predictors for coronary arterial lesion in hypertensive patients.

Thoracic and abdominal aortas stiffen through unique extracellular matrix changes in intrauterine growth restricted fetal sheep.

PubMed

Dodson, R Blair; Rozance, Paul J; Petrash, Carson C; Hunter, Kendall S; Ferguson, Virginia L

2014-02-01

Intrauterine growth restriction (IUGR) is a fetal complication of pregnancy epidemiologically linked to cardiovascular disease in the newborn later in life. However, the mechanism is poorly understood with very little research on the vascular structure and function during development in healthy and IUGR neonates. Previously, we found vascular remodeling and increased stiffness in the carotid and umbilical arteries, but here we examine the remodeling and biomechanics in the larger vessels more proximal to the heart. To study this question, thoracic and abdominal aortas were collected from a sheep model of placental insufficiency IUGR (PI-IUGR) due to exposure to elevated ambient temperatures. Aortas from control (n = 12) and PI-IUGR fetuses (n = 10) were analyzed for functional biomechanics and structural remodeling. PI-IUGR aortas had a significant increase in stiffness (P < 0.05), increased collagen content (P < 0.05), and decreased sulfated glycosaminoglycan content (P < 0.05). Our derived constitutive model from experimental data related increased stiffness to reorganization changes of increased alignment angle of collagen fibers and increased elastin (P < 0.05) in the thoracic aorta and increased concentration of collagen fibers in the abdominal aorta toward the circumferential direction verified through use of histological techniques. This fetal vascular remodeling in PI-IUGR may set the stage for possible altered growth and development and help to explain the pathophysiology of adult cardiovascular disease in previously IUGR individuals.

Failure of the Porcine Ascending Aorta: Multidirectional Experiments and a Unifying Microstructural Model

PubMed Central

Witzenburg, Colleen M.; Dhume, Rohit Y.; Shah, Sachin B.; Korenczuk, Christopher E.; Wagner, Hallie P.; Alford, Patrick W.; Barocas, Victor H.

2017-01-01

The ascending thoracic aorta is poorly understood mechanically, especially its risk of dissection. To make better predictions of dissection risk, more information about the multidimensional failure behavior of the tissue is needed, and this information must be incorporated into an appropriate theoretical/computational model. Toward the creation of such a model, uniaxial, equibiaxial, peel, and shear lap tests were performed on healthy porcine ascending aorta samples. Uniaxial and equibiaxial tests showed anisotropy with greater stiffness and strength in the circumferential direction. Shear lap tests showed catastrophic failure at shear stresses (150–200 kPa) much lower than uniaxial tests (750–2500 kPa), consistent with the low peel tension (∼60 mN/mm). A novel multiscale computational model, including both prefailure and failure mechanics of the aorta, was developed. The microstructural part of the model included contributions from a collagen-reinforced elastin sheet and interlamellar connections representing fibrillin and smooth muscle. Components were represented as nonlinear fibers that failed at a critical stretch. Multiscale simulations of the different experiments were performed, and the model, appropriately specified, agreed well with all experimental data, representing a uniquely complete structure-based description of aorta mechanics. In addition, our experiments and model demonstrate the very low strength of the aorta in radial shear, suggesting an important possible mechanism for aortic dissection. PMID:27893044

Hemolytic anemia caused by aortic flap and inversion of felt strip after ascending aorta replacement.

PubMed

Sakaguchi, Masayuki; Takano, Tamaki

2016-08-02

Hemolysis related to a kinked prosthetic graft or inner felt strip is a very rare complication after aortic surgery. We describe herein a case of hemolytic anemia that developed due to aortic flap of the dissection and inversion of an inner felt strip that was applied at the proximal anastomosis of a replaced ascending aorta 10 years previously. A 74-year-old woman presented with consistent hemolytic anemia 10 years after replacement of the ascending aorta to treat Stanford type A acute aortic dissection. The cause of hemolysis was attributed to mechanical injury of red blood cells at a site of stenosis caused by aortic flap of the dissection and inversion of the felt strip used for the proximal anastomosis. Repeated resection of the strip and graft replacement of the ascending aorta resolved this problem. We considered that blood flow disrupted by a jet of blood at the site of the proximal inner felt strip was the cause of severe hemolysis, we describe rare hemolytic anemia at the site of aortic flap and inverted felt strip after replacement of the ascending aorta.

Taxifolin and Fucoidin Abolish the Irradiation-Induced Increase in the Production of Reactive Oxygen Species in Rat Aorta.

PubMed

Arutyunyan, T V; Korystova, A F; Kublik, L N; Levitman, M Kh; Shaposhnikova, V V; Korystov, Yu N

2016-03-01

We studied changes in ROS content in the aorta of Wistar rats at early terms after irradiation in doses equal to single fraction used in tumor radiotherapy and the effects of taxifolin and fucoidin, blockers of leukocyte adhesion to endothelium, on ROS content. Male rats were exposed to X-rays (200 kW) in doses of 1-7.5 Gy. ROS production in aorta segments was measured in 1-48 h after irradiation by dichlorodihydrofluorescein oxidation. The content of ROS in the aorta of rats exposed to radiation in doses of 1-2.5 Gy increased in 1-24 h after irradiation, the peak ROS content was found in 2 h after irradiation. Taxifolin (100 μg/kg dihydroquercetin once a day with drinking water) and fucoidin (10 mg/kg, i.v.) abolished ROS accumulation. The content of ROS in rat aorta increased in 1-24 h after irradiation in doses used for tumor radiotherapy and this increase can be determined by leukocyte adhesion to the endothelium.

TAVR Through Heavily Calcified Aorta Following Atheroma Retrieval With the "Elevator" Technique.

PubMed

Senguttuvan, N Boopathy; Ellozy, Sharif; Tejani, Furqan; Kovacic, Jason; Kini, Annapoorna S; Sharma, Samin K; Dangas, George D

2015-10-01

An 86-year-old Caucasian female with severe symptomatic, inoperable aortic stenosis was accepted for high-risk transfemoral transcatheter aortic valve replacement (TAVR) approach due to severe calcification of the aorta. During initial passage of a 22 Fr sheath, there was dislodgment with proximal migration of a circumferential tunnel of calcium from the infrarenal aorta. A novel "elevator" technique was used to secure and retrieve the dislodged aorta en bloc back to its original infrarenal aortic position and allow in situ fixation with stenting. A new TAVR system was then successfully placed through the stent and a 23 mm Edwards Sapien valve (Edwards Lifesciences) was implanted as planned. In case of calcification protruding into the lumen of the aorta and limiting the passage of the large valve delivery system sheath, the obstruction can be managed by stenting the calcification against the luminal wall under fluoroscopic and intravascular-ultrasound guidance, allowing successful passage of the valve delivery system. The elevator technique allows axial transportation of any calcified vascular fragments, should they become dislodged.

A mathematical model of aortic aneurysm formation

PubMed Central

Hao, Wenrui; Gong, Shihua; Wu, Shuonan; Xu, Jinchao; Go, Michael R.; Friedman, Avner; Zhu, Dai

2017-01-01

Abdominal aortic aneurysm (AAA) is a localized enlargement of the abdominal aorta, such that the diameter exceeds 3 cm. The natural history of AAA is progressive growth leading to rupture, an event that carries up to 90% risk of mortality. Hence there is a need to predict the growth of the diameter of the aorta based on the diameter of a patient’s aneurysm at initial screening and aided by non-invasive biomarkers. IL-6 is overexpressed in AAA and was suggested as a prognostic marker for the risk in AAA. The present paper develops a mathematical model which relates the growth of the abdominal aorta to the serum concentration of IL-6. Given the initial diameter of the aorta and the serum concentration of IL-6, the model predicts the growth of the diameter at subsequent times. Such a prediction can provide guidance to how closely the patient’s abdominal aorta should be monitored. The mathematical model is represented by a system of partial differential equations taking place in the aortic wall, where the media is assumed to have the constituency of an hyperelastic material. PMID:28212412

Esophageal Cancer

MedlinePlus

... Heart Disease Diseases of the arteries, valves, and aorta, as well as cardiac rhythm disturbances Aortic Valve ... Transposition of the Great Arteries Coarctation of the Aorta Truncus Arteriosus Single Ventricle Defects Patent Ductus Arteriosus ...

Aortic Dissection

MedlinePlus

... condition in which the inner layer of the aorta, the large blood vessel branching off the heart, ... causing the inner and middle layers of the aorta to separate (dissect). If the blood-filled channel ...

Aneurysm Repair

MedlinePlus

... heart to other parts of the body (the aorta). Aortic aneurysms can occur in the area below ... Aortic aneurysms in the upper chest (the ascending aorta) are usually operated on right away. Aneurysms in ...

Isolated Aortitis

MedlinePlus

... a general term which means inflammation of the aorta, the large blood vessel which transports blood from ... The aortic root is the part of the aorta which is directly connected to the left ventricle ( ...

Marfan Syndrome

MedlinePlus

... Over time, weak connective tissue can cause the aorta, the large artery that carries blood away from ... DYE-late), or widen. If not treated, the aorta can suddenly tear, causing blood to leak out. ...

Coronary Arteries

MedlinePlus

... its own vascular system, called coronary circulation. The aorta (the main blood supplier to the body) branches ... blood to the rest of the body. Tags: aorta , arteries , blood , coronary arteries , coronary artery , coronary artery ...

Aortic Aneurysm

MedlinePlus

... or even death. Most aneurysms are in the aorta, the main artery that runs from the heart ... TAA) - these occur in the part of the aorta running through the chest Abdominal aortic aneurysms (AAA) - ...

Truncus arteriosus

MedlinePlus

... of the normal 2 vessels (pulmonary artery and aorta). It is present at birth ( congenital heart disease ). ... comes out of the right ventricle and the aorta comes out of the left ventricle, which are ...

CFD analysis of multiphase blood flow within aorta and its thoracic branches of patient with coarctation of aorta using multiphase Euler - Euler approach

NASA Astrophysics Data System (ADS)

Ostrowski, Z.; Melka, B.; Adamczyk, W.; Rojczyk, M.; Golda, A.; Nowak, A. J.

2016-09-01

In the research a numerical Computational Fluid Dynamics (CFD) model of the pulsatile blood flow was created and analyzed. A real geometry of aorta and its thoracic branches of 8-year old patient diagnosed with a congenital heart defect - coarctation of aorta was used. The inlet boundary condition were implemented as the User Define Function according to measured values of volumetric blood flow. The blood flow was treated as multiphase: plasma, set as the primary fluid phase, was dominant with volume fraction of 0.585 and morphological elements of blood were treated in Euler-Euler approach as dispersed phases (with 90% Red Blood Cells and White Blood Cells as remaining solid volume fraction).

Alteration of time-resolved autofluorescence properties of rat aorta, induced by diabetes mellitus

NASA Astrophysics Data System (ADS)

Uherek, M.; Uličná, O.; Vančová, O.; Muchová, J.; Ďuračková, Z.; Šikurová, L.; Chorvát, D.

2016-10-01

Changes in autofluorescence properties of isolated rat aorta, induced by diabetes mellitus, were detected using time-resolved fluorescence spectroscopy with pulsed ultraviolet (UV) laser excitation. We demonstrated that time-resolved spectroscopy was able to detect changes in aorta tissues related to diabetes and unambiguously discriminate diabetic (τ 1 0.63  ±  0.05 ns, τ 2 3.66  ±  0.10 ns) samples from the control (τ 1 0.76  ±  0.03 ns, τ 2 4.48  ±  0.15 ns) group. We also report changes in the ratio of relative amplitudes of the two lifetime component in aorta tissue during diabetes, most likely related to the pseudohypoxic state with altered NADH homeostasis.

Biophysics of cardiopulmonary resuscitation with periodic z-axis acceleration or abdominal compression at aortic resonant frequencies.

PubMed

Babbs, Charles F

2006-06-01

Periodic z-axis acceleration (pGz)-CPR involves an oscillating motion of a whole patient in the head-to-foot dimension on a mechanized table. The method is able to sustain blood flow and long-term survival during and after prolonged cardiac arrest in anesthetized pigs. However, the exact mechanism by which circulation of blood is created has remained unknown. To explain the hemodynamic mechanism of pGz-CPR and to suggest some theoretically useful improvements. Computer modeling using a hybrid analytical-numerical approach, based upon Newton's second law of motion for fluid columns in the aorta and vena cavae, Ohm's law for resistive flow through vascular beds, and a 10-compartment representation of the adult human circulation. This idealized 70-kg human model is exercised to explore the effects upon systemic perfusion pressure of whole body z-axis acceleration at frequencies ranging from 0.5 to 5 Hz. The results, in turn, suggested studies of abdominal compression at these frequencies. Blood motion induced in great vessels by periodic z-axis acceleration causes systemic perfusion when cardiac valves are competent. Blood flow is a function of the frequency of oscillation. At 3.5 Hz, periodic acceleration using +/-0.6G and +/-1.2 cm oscillations induces forward blood flow of 2.1L/min and systemic perfusion pressure of 47 mmHg. A form of resonance occurs at the frequency for peak-flow, in which the period of oscillation matches the round-trip transit time for reflected pulse waves in the aorta. For +/-1.0 G acceleration at 3.5 Hz, systemic perfusion pressure is 80 mmHg and forward flow is 3.8L/min in the adult human model with longitudinal z-axis motion of only +/-2 cm. Similar results can be obtained using abdominal compression to excite resonant pressure-volume waves in the aorta. For 20 mmHg abdominal pressure pulses at 3.8 Hz, systemic perfusion pressure is 7 mmHg and forward flow is 2.8L/min. pGz-CPR and high-frequency abdominal CPR are the physically realistic means of generating artificial circulation during cardiac arrest. These techniques have fundamental mechanisms and practical features quite different from those of conventional CPR and the potential to generate superior systemic perfusion.

Modelling the layer-specific three-dimensional residual stresses in arteries, with an application to the human aorta

PubMed Central

Holzapfel, Gerhard A.; Ogden, Ray W.

2010-01-01

This paper provides the first analysis of the three-dimensional state of residual stress and stretch in an artery wall consisting of three layers (intima, media and adventitia), modelled as a circular cylindrical tube. The analysis is based on experimental results on human aortas with non-atherosclerotic intimal thickening documented in a recent paper by Holzapfel et al. ( Holzapfel et al. 2007 Ann. Biomed. Eng. 35, 530–545 (doi:10.1007/s10439-006-9252-z)). The intima is included in the analysis because it has significant thickness and load-bearing capacity, unlike in a young, healthy human aorta. The mathematical model takes account of bending and stretching in both the circumferential and axial directions in each layer of the wall. Previous analysis of residual stress was essentially based on a simple application of the opening-angle method, which cannot accommodate the three-dimensional residual stretch and stress states observed in experiments. The geometry and nonlinear kinematics of the intima, media and adventitia are derived and the associated stress components determined explicitly using the nonlinear theory of elasticity. The theoretical results are then combined with the mean numerical values of the geometrical parameters and material constants from the experiments to illustrate the three-dimensional distributions of the stretches and stresses throughout the wall. The results highlight the compressive nature of the circumferential stress in the intima, which may be associated with buckling of the intima and its delamination from the media, and show that the qualitative features of the stretch and stress distributions in the media and adventitia are unaffected by the presence or absence of the intima. The circumferential residual stress in the intima increases significantly as the associated residual deformation in the intima increases while the corresponding stress in the media (which is compressive at its inner boundary and tensile at its outer boundary) is only slightly affected. The theoretical framework developed herein enables the state of residual stress to be calculated directly, serves to improve insight into the mechanical response of an unloaded artery wall and can be extended to accommodate more general geometries, kinematics and states of residual stress as well as more general constitutive models. PMID:19828496

Heart in TLC

MedlinePlus

... Although rare, some patients have coarctation of the aorta, renal artery stenosis, or thoracic or abdominal aneurysms. ... and thoracic vascular abnormalities, including coarctation of the aorta. An abdominal ultrasound is the initial modality of ...

Aortic Valve Regurgitation

MedlinePlus

... the main artery that leads to the body (aorta) doesn't close properly, which causes some blood ... Other diseases. Other rare conditions can enlarge the aorta and aortic valve and lead to regurgitation, including ...

Mesenteric artery ischemia

MedlinePlus

... blood to the intestines run directly from the aorta, the main artery from the heart. Hardening of ... clots most often come from the heart or aorta. These clots are more commonly seen in people ...

Self-Expanding, Tough Biodegradable Elastomers for Wound Stasis

DTIC Science & Technology

2015-08-06

laparotomy and small bowel was retracted to identify the abdominal aorta and vena cava. The peritoneumwas incised along a 3 cm length of the right external...Resuscitation protocol Duration Mortality Blood loss Sondeen et al. [7] Open 4.4 mm perforation of abdominal aorta 100% 300 mL/min IV lactated Ringer...g/kg Control 3. 50% 15 g/kg Kheirabadi et al. [6] Open 4.4 mm perforation of infrarenal aorta 100% Lactated Ringers, 3 pretreatment blood volume at

Left ventricle descending aorta valved conduit to relieve congenital aortic stenosis in children.

PubMed

Eijgelaar, A; Hess, J; Cromme-Dijkhuis, A H; Karliczek, G F; Homan van der Heide, J N

1984-10-01

A valved conduit was inserted between the apex of the left ventricle and the descending aorta in 2 patients, 4 months and 10 years of age, respectively, who had valvular aortic stenosis. The development of both patients has been excellent since operation. At control catheterization (1 and 2 years postoperatively) no pressure gradient was found between the left ventricle and the aorta. In both patients the aortic valve area showed growth to near normal size on echocardiographic study 3 years postoperatively.

Left aortic arch with right-sided descending aorta associated with sudden neonatal death: a case report.

PubMed

Pampin, J Blanco; Rivero, A Garcia; Tamayo, N Morte; Fonseca, R Hinojal

2003-10-01

We present the case of a 26-day-old female in whom left aortic arch with right-sided descending aorta occurred. The previously healthy newborn baby was found dead on her bed. This anomaly is very uncommon and its clinical presentation as sudden death is also exceptional with only a few cases having been reported in the literature. The pathological findings and embryological origins of this malformation, so-called 'circumflex aorta' are discussed. The pertinent literature is reviewed.

Streptococcus pyogenes Phospholipase A2 Induces the Expression of Adhesion Molecules on Human Umbilical Vein Endothelial Cells and Aorta of Mice.

PubMed

Oda, Masataka; Domon, Hisanori; Kurosawa, Mie; Isono, Toshihito; Maekawa, Tomoki; Yamaguchi, Masaya; Kawabata, Shigetada; Terao, Yutaka

2017-01-01

The Streptococcus pyogenes phospholipase A 2 (SlaA) gene is highly conserved in the M3 serotype of group A S. pyogenes , which often involves hypervirulent clones. However, the role of SlaA in S. pyogenes pathogenesis is unclear. Herein, we report that SlaA induces the expression of intercellular adhesion molecule 1 (ICAM1) and vascular cell adhesion molecule 1 (VCAM1) via the arachidonic acid signaling cascade. Notably, recombinant SlaA induced ICAM1 and VCAM1 expression in human umbilical vein endothelial cells (HUVECs), resulting in enhanced adhesion of human monocytic leukemia (THP-1) cells. However, C134A, a variant enzyme with no enzymatic activity, did not induce such events. In addition, culture supernatants from S. pyogenes SSI-1 enhanced the adhesion of THP-1 cells to HUVECs, but culture supernatants from the Δ slaA isogenic mutant strain had limited effects. Aspirin, a cyclooxygenase 2 inhibitor, prevented the adhesion of THP-1 cells to HUVECs and did not induce ICAM1 and VCAM1 expression in HUVECs treated with SlaA. However, zileuton, a 5-lipoxygenase inhibitor, did not exhibit such effects. Furthermore, pre-administration of aspirin in mice intravenously injected with SlaA attenuated the transcriptional abundance of ICAM1 and VCAM1 in the aorta. These results suggested that SlaA from S. pyogenes stimulates the expression of adhesion molecules in vascular endothelial cells. Thus, SlaA contributes to the inflammation of vascular endothelial cells upon S. pyogenes infection.

Learning about Turner Syndrome

MedlinePlus

... heart murmur, sometimes associated with narrowing of the aorta (blood vessel exiting the heart). A tendency to ... with a heart murmur or narrowing of the aorta may need surgery to correct the problem. A ...

Double outlet right ventricle

MedlinePlus

... disease that is present from birth (congenital) . The aorta connects to the right ventricle (RV, the chamber ... carries oxygen-poor blood to the lungs) and aorta (which carries oxygen-rich blood from the heart ...

Learning about Marfan Syndrome

MedlinePlus

... threatening symptom of Marfan syndrome. They include dilated aorta just as it leaves the heart (at the ... clinical diagnostic features: Dilatation or dissection of the aorta at the level of the sinuses of Valsava. ...

Abdominal Aortic Aneurysm (AAA)

MedlinePlus

... plaque buildup causes the walls of the abdominal aorta to become weak and bulge outward like a ... treated? What is an abdominal aortic aneurysm? The aorta, the largest artery in the body, is a ...

Double Outlet Right Ventricle

MedlinePlus

... the right ventricle into the lungs, and the aorta sends oxygen-rich blood from the left ventricle ... the body. Together, the pulmonary artery and the aorta are known as the great arteries. But with ...

Facts about Truncus Arteriosis

MedlinePlus

... Septal Defect Atrioventricular Septal Defect Coarctation of the Aorta D-Transposition of the Great Arteries Hypoplastic Left ... usual two vessels (the main pulmonary artery and aorta ). What is Truncus Arteriosus Click here to view ...

Transposition of the great arteries

MedlinePlus

... that carry blood away from the heart -- the aorta and the pulmonary artery -- are switched (transposed). ... side of the heart and travels out the aorta to the body. In TGA, venous blood returns ...

Marfan Syndrome (For Parents)

MedlinePlus

... have other medical problems, including: enlargement of the aorta (the large blood vessel that carries blood from ... to the body). If the wall of the aorta becomes very weak, it can tear and lead ...

Takayasu's Arteritis

MedlinePlus

... the largest blood vessel in the body (the aorta) and its branches. Thus, the complications of Takayasu’s ... with Takayasu’s, with obvious dilation of the ascending aorta on the left side of the picture. Clinicians ...

Transient Receptor Potential Channel Opening Releases Endogenous Acetylcholine, which Contributes to Endothelium-Dependent Relaxation Induced by Mild Hypothermia in Spontaneously Hypertensive Rat but Not Wistar-Kyoto Rat Arteries.

PubMed

Zou, Q; Leung, S W S; Vanhoutte, P M

2015-08-01

Mild hypothermia causes endothelium-dependent relaxations, which are reduced by the muscarinic receptor antagonist atropine. The present study investigated whether endothelial endogenous acetylcholine contributes to these relaxations. Aortic rings of spontaneously hypertensive rats (SHRs) and normotensive Wistar-Kyoto (WKY) rats were contracted with prostaglandin F2 α and exposed to progressive mild hypothermia (from 37 to 31°C). Hypothermia induced endothelium-dependent, Nω-nitro-l-arginine methyl ester-sensitive relaxations, which were reduced by atropine, but not by mecamylamine, in SHR but not in WKY rat aortae. The responses in SHR aortae were also reduced by acetylcholinesterase (the enzyme responsible for acetylcholine degradation), bromoacetylcholine (inhibitor of acetylcholine synthesis), hemicholinium-3 (inhibitor of choline uptake), and vesamicol (inhibitor of acetylcholine release). The mild hypothermia-induced relaxations in both SHR and WKY rat aortae were inhibited by AMTB [N-(3-aminopropyl)-2-[(3-methylphenyl)methoxy]-N-(2-thienylmethyl)-benzamide; the transient receptor potential (TRP) M8 inhibitor]; only those in SHR aortae were inhibited by HC-067047 [2-methyl-1-[3-(4-morpholinyl)propyl]-5-phenyl-N-[3-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxamide; TRPV4 antagonist] while those in WKY rat aortae were reduced by HC-030031 [2-(1,3-dimethyl-2,6-dioxo-1,2,3,6-tetrahydro-7H-purin-7-yl)-N-(4-isopropylphenyl)acetamide; TRPA1 antagonist]. The endothelial uptake of extracellular choline and release of cyclic guanosine monophosphate was enhanced by mild hypothermia and inhibited by HC-067047 in SHR but not in WKY rat aortae. Compared with WKY rats, the SHR preparations expressed similar levels of acetylcholinesterase and choline acetyltransferase, but a lesser amount of vesicular acetylcholine transporter, located mainly in the endothelium. Thus, mild hypothermia causes nitric oxide-dependent relaxations by opening TRPA1 channels in WKY rat aortae. By contrast, in SHR aortae, TRPV4 channels are opened, resulting in endothelial production of acetylcholine, which, in an autocrine manner, activates muscarinic receptors on neighboring cells to elicit endothelium-dependent relaxations in response to mild hypothermia. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

Proximal thoracic aorta dimensions after continuous-flow left ventricular assist device implantation: Longitudinal changes and relation to aortic valve insufficiency.

PubMed

Fine, Nowell M; Park, Soon J; Stulak, John M; Topilsky, Yan; Daly, Richard C; Joyce, Lyle D; Pereira, Naveen L; Schirger, John A; Edwards, Brooks S; Lin, Grace; Kushwaha, Sudhir S

2016-04-01

In this study we examined the impact of continuous-flow left ventricular assist device (CF-LVAD) support on proximal thoracic aorta dimensions. Aortic root and ascending aorta diameter were measured from serial echocardiograms before and after CF-LVAD implantation in patients with ≥6 months of support, and correlated with the development of >mild aortic valve insufficiency (AI). Of 162 patients included, mean age was 58 ± 11 years and 128 (79%) were male. Seventy-nine (63%) were destination therapy patients. Mean aortic root and ascending aorta diameters at baseline, 1 month, 6 months, 12 months and long-term follow-up (mean 2.0 ± 1.4 years) were 3.5 ± 0.4, 3.5 ± 0.3, 3.9 ± 0.3, 3.9 ± 0.2 and 4.0 ± 0.3, and 3.3 ± 0.2, 3.3 ± 0.3, 3.6 ± 0.2, 3.6 ± 0.3 and 3.6 ± 0.3 cm, respectively. Only change in aortic root diameter from 1-month to 6-month follow-up reached statistical significance (p = 0.03). Nine (6%) patients had accelerated proximal thoracic aorta expansion (>0.5 cm/year), occurring predominantly in the first 6 months after implantation. These patients were older and more likely to have hypertension and baseline proximal thoracic aorta dilation. Forty-five (28%) patients developed >mild AI at long-term follow-up, including 7 of 9 (78%) of those with accelerated proximal thoracic aorta expansion. All 7 had aortic valves that remained closed throughout the cardiac cycle, and this, along with duration of CF-LVAD support and increase in aortic root diameter, were significantly associated with developing >mild AI. CF-LVAD patients have small increases in proximal thoracic aorta dimensions that predominantly occur within the first 6 months after implantation and then stabilize. Increasing aortic root diameter was associated with AI development. Copyright © 2016 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

Annual Research Progress Report Fiscal Year 1987. Volume 1,

DTIC Science & Technology

1987-10-01

Constrictive Pericarditis 86 in Patients. (0) C-20-85 Pressure Waveforms and Reflections in the Human Aorta: Compari- 87 son of a Cadaver Model with In...in Constrictive 125 Pericarditis . (0) C-60-86 The Natural History of HTLV-III Infection and Disease in a 126 United States Military Population. (0...Sheet Date: 18 Mar 87 Proj No: C-16-85 Status: Terminated Title: Significance of Post Radiotherapy Constrictive Pericarditis in Patients. Start Date 21

The influence of angiotensin-converting enzyme inhibitors on the aorta elastin metabolism in diet-induced hypercholesterolaemia in rabbits.

PubMed

Wojakowski, W; Gminski, J; Siemianowicz, K; Goss, M; Machalski, M

2001-03-01

Aortic elastin turnover is significantly accelerated in atherosclerosis, partly because of activation of the renin-angiotensin-aldosterone system caused by hypercholesterolaemia. We postulated that angiotensin-converting enzyme inhibitors (ACE-I) prevent the aortic elastin loss in experimental hypercholesterolaemia. Two doses of ACE-I (captopril, enalapril and quinapril) were used: a dose equivalent to that applied to human subjects and a dose 10 times higher. We found that the increase in serum and aortic elastolytic activity in cholesterol-fed rabbits was prevented by high-dose captopril. The elastin content in aorta homogenates from cholesterol-fed rabbits was significantly decreased. The higher dose of captopril, but no other ACE-I, prevented this decrease in aortic elastin content. In cholesterol-fed rabbits the elastin-bound calcium content was significantly elevated. The higher doses of captopril and enalapril lowered the elastin-bound calcium content. In serum and aortic homogenates of cholesterol-fed rabbits, ACE activity was elevated by 15% and 77%, respectively. Both doses of captopril, enalapril and quinapril prevented this cholesterol-induced increase in serum and aortic ACE activity. We conclude that: 1) administration of captopril at doses 10 times higher than those used in humans prevents hypercholesterolaemia increased aortic elastin loss. 2) higher doses of captopril and enalapril prevent the hypercholesterolaemia-induced increase in aortic elastin-bound calcium.

Single- and double-walled carbon nanotubes enhance atherosclerogenesis by promoting monocyte adhesion to endothelial cells and endothelial progenitor cell dysfunction.

PubMed

Suzuki, Yuka; Tada-Oikawa, Saeko; Hayashi, Yasuhiko; Izuoka, Kiyora; Kataoka, Misa; Ichikawa, Shunsuke; Wu, Wenting; Zong, Cai; Ichihara, Gaku; Ichihara, Sahoko

2016-10-13

The use of carbon nanotubes has increased lately. However, the cardiovascular effect of exposure to carbon nanotubes remains elusive. The present study investigated the effects of pulmonary exposure to single-walled carbon nanotubes (SWCNTs) and double-walled carbon nanotubes (DWCNTs) on atherosclerogenesis using normal human aortic endothelial cells (HAECs) and apolipoprotein E-deficient (ApoE -/- ) mice, a model of human atherosclerosis. HAECs were cultured and exposed to SWCNTs or DWCNTs for 16 h. ApoE -/- mice were exposed to SWCNTs or DWCNTs (10 or 40 μg/mouse) once every other week for 10 weeks by pharyngeal aspiration. Exposure to CNTs increased the expression level of adhesion molecule (ICAM-1) and enhanced THP-1 monocyte adhesion to HAECs. ApoE -/- mice exposed to CNTs showed increased plaque area in the aorta by oil red O staining and up-regulation of ICAM-1 expression in the aorta, compared with vehicle-treated ApoE -/- mice. Endothelial progenitor cells (EPCs) are mobilized from the bone marrow into the circulation and subsequently migrate to the site of endothelial damage and repair. Exposure of ApoE -/- mice to high-dose SWCNTs or DWCNTs reduced the colony-forming units of EPCs in the bone marrow and diminished their migration function. The results suggested that SWCNTs and DWCNTs enhanced atherosclerogenesis by promoting monocyte adhesion to endothelial cells and inducing EPC dysfunction.

3D MR flow analysis in realistic rapid-prototyping model systems of the thoracic aorta: comparison with in vivo data and computational fluid dynamics in identical vessel geometries.

PubMed

Canstein, C; Cachot, P; Faust, A; Stalder, A F; Bock, J; Frydrychowicz, A; Küffer, J; Hennig, J; Markl, M

2008-03-01

The knowledge of local vascular anatomy and function in the human body is of high interest for the diagnosis and treatment of cardiovascular disease. A comprehensive analysis of the hemodynamics in the thoracic aorta is presented based on the integration of flow-sensitive 4D MRI with state-of-the-art rapid prototyping technology and computational fluid dynamics (CFD). Rapid prototyping was used to transform aortic geometries as measured by contrast-enhanced MR angiography into realistic vascular models with large anatomical coverage. Integration into a flow circuit with patient-specific pulsatile in-flow conditions and application of flow-sensitive 4D MRI permitted detailed analysis of local and global 3D flow dynamics in a realistic vascular geometry. Visualization of characteristic 3D flow patterns and quantitative comparisons of the in vitro experiments with in vivo data and CFD simulations in identical vascular geometries were performed to evaluate the accuracy of vascular model systems. The results indicate the potential of such patient-specific model systems for detailed experimental simulation of realistic vascular hemodynamics. Further studies are warranted to examine the influence of refined boundary conditions of the human circulatory system such as fluid-wall interaction and their effect on normal and pathological blood flow characteristics associated with vascular geometry. (c) 2008 Wiley-Liss, Inc.

Locally Applied Leptin Induces Regional Aortic Wall Degeneration Preceding Aneurysm Formation in ApoE Deficient Mice

PubMed Central

Tao, Ming; Yu, Peng; Nguyen, Binh T.; Mizrahi, Boaz; Savion, Naphtali; Kolodgie, Frank D.; Virmani, Renu; Hao, Shuai; Ozaki, C. Keith; Schneiderman, Jacob

2013-01-01

Objective Leptin promotes atherosclerosis and vessel wall remodeling. As abdominal aorta aneurysm (AAA) formation involves tissue remodeling, we hypothesized that local leptin synthesis initiates and promotes this process. Methods and Results Human surgical AAA walls were analyzed for antigen and mRNA levels of leptin and leptin receptor (ObR), as well as mRNA for matrix metalloproteinases (MMP)-9, and MMP-12. Leptin and ObR antigen were evident in all AAAs, and, leptin, MMP-9, and MMP-12 mRNA was increased relative to age-matched non-dilated controls. To simulate in vivo local leptin synthesis, ApoE-/- mice were subjected to a para-visceral peri-aortic application of low-dose leptin. Leptin-treated aortas exhibited decreased TGFβ and increased MMP-9 mRNA levels 5 days after surgery, and ObR mRNA was up-regulated by day 28. Serial ultrasonography demonstrated accelerated regional aortic diameter growth after 28 days, correlating with local medial degeneration, increased MMP-9, MMP-12 and peri-adventitial macrophage clustering. Furthermore, the combination of local peri-aortic leptin and systemic angiotensin II administration augmented medial MMP-9 synthesis and aortic aneurysm size. Conclusions Leptin is locally synthesized in human AAA wall. Para-visceral aortic leptin in ApoE-/- mice induces local medial degeneration, and augments angiotensin II-induced AAA, thus suggesting novel mechanistic links between leptin and AAA formation. PMID:23220275

Congenital heart defect - corrective surgery

MedlinePlus

... repair; Tetralogy of Fallot repair; Coarctation of the aorta repair; Atrial septal defect repair; Ventricular septal defect ... has a blood vessel that runs between the aorta (the main artery to the body) and the ...

Aortic aneurysm repair - endovascular - discharge

MedlinePlus

... artery that carries blood to your lower body (aorta). To perform the procedure: Your doctor made a ... to guide the stent and graft into your aorta where the aneurysm was located. The graft and ...

What Is a Cardiothoracic Surgeon?

MedlinePlus

... Heart Disease Diseases of the arteries, valves, and aorta, as well as cardiac rhythm disturbances Aortic Valve ... Transposition of the Great Arteries Coarctation of the Aorta Truncus Arteriosus Single Ventricle Defects Patent Ductus Arteriosus ...

Birth Defects Data and Statistics

MedlinePlus

... Septal Defect Atrioventricular Septal Defect Coarctation of the Aorta D-Transposition of the Great Arteries Hypoplastic Left ... Syndrome Disorders Gastroschisis Heart Defects Coarctation of the Aorta Hypoplastic left heart syndrome Tetralogy of Fallot Other ...

A fiber-based constitutive model predicts changes in amount and organization of matrix proteins with development and disease in the mouse aorta

PubMed Central

Cheng, Jeffrey K.; Stoilov, Ivan; Mecham, Robert P.

2013-01-01

Decreased elastin in mice (Eln+/−) yields a functioning vascular system with elevated blood pressure and increased arterial stiffness that is morphologically distinct from wild-type mice (WT). Yet, function is retained enough that there is no appreciable effect on life span and some mechanical properties are maintained constant. It is not understood how the mouse modifies the normal developmental process to produce a functioning vascular system despite a deficiency in elastin. To quantify changes in mechanical properties, we have applied a fiber-based constitutive model to mechanical data from the ascending aorta during postnatal development of WT and Eln+/− mice. Results indicate that the fiber-based constitutive model is capable of distinguishing elastin amounts and identifying trends during development. We observe an increase in predicted circumferential stress contribution from elastin with age, which correlates with increased elastin amounts from protein quantification data. The model also predicts changes in the unloaded collagen fiber orientation with age, which must be verified in future work. In Eln+/− mice, elastin amounts are decreased at each age, along with the predicted circumferential stress contribution of elastin. Collagen amounts in Eln+/− aorta are comparable to WT, but the predicted circumferential stress contribution of collagen is increased. This may be due to altered organization or structure of the collagen fibers. Relating quantifiable changes in arterial mechanics with changes in extracellular matrix (ECM) protein amounts will help in understanding developmental remodeling and in producing treatments for human diseases affecting ECM proteins. PMID:22790326

The right intercostobronchial trunk: anatomical study in respect of posterior intercostal artery origin and its clinical application.

PubMed

Kocbek, Lidija; Rakuša, Mateja

2018-01-01

The right bronchial artery usually arises from the descending thoracic aorta as a common trunk with the right intercostal artery and forms the right intercostobronchial trunk. Both, the third right posterior intercostal artery and the right intercostobronchial trunk, are described as the most constant vessels. The focus of the study was to determine the characteristics of the right intercostobronchial trunk regarding the origins of the posterior intercostal arteries from the thoracic aorta. Posterior intercostal arteries and the right bronchial arteries were dissected in 43 human cadavers, preserved after Thiel's embalming method with intraarterial infusion of red colored latex. Postmortem examination gave valued information on the right intercostobronchial trunk present in 58% of cases. The right intercostobronchial trunk was mapped and new classification regarding the origin of the posterior intercostal arteries from the thoracic aorta suggested type A, B and C, the latter ones into subtypes 1 and 2. Type A was proportional to the origin level of the PIA and its corresponding intercostal space. Size of outer diameter at the origin did not indicate the right bronchial artery branch. In subtype 2 of type B the proximal posterior intercostal artery diameter that gave off right bronchial artery was thicker than distal one. The right bronchial artery originates from the second to the fifth posterior intercostal artery forming the right intercostobronchial trunk. Various origin and types of origin, diameter and course of the right intercostobronchial trunk described and analyzed in the study offer valuable information on the procedures involving the right intercostobronchial trunk.

Enhanced delineation of degradation in aortic walls through OCT

NASA Astrophysics Data System (ADS)

Real, Eusebio; Val-Bernal, José Fernando; Revuelta, José M.; Pontón, Alejandro; Calvo Díez, Marta; Mayorga, Marta; López-Higuera, José M.; Conde, Olga M.

2015-03-01

Degradation of the wall of human ascending thoracic aorta has been assessed through Optical Coherence Tomography (OCT). OCT images of the media layer of the aortic wall exhibit micro-structure degradation in case of diseased aortas from aneurysmal vessels or in aortas prone to aortic dissections. The degeneration in vessel walls appears as low-reflectivity areas due to the invasive appearance of acidic polysaccharides and mucopolysaccharides within a typical ordered microstructure of parallel lamellae of smooth muscle cells, elastin and collagen fibers. An OCT indicator of wall degradation can be generated upon the spatial quantification of the extension of degraded areas in a similar way as conventional histopathology. This proposed OCT marker offers a real-time clinical insight of the vessel status to help cardiovascular surgeons in vessel repair interventions. However, the delineation of degraded areas on the B-scan image from OCT is sometimes difficult due to presence of speckle noise, variable SNR conditions on the measurement process, etc. Degraded areas could be outlined by basic thresholding techniques taking advantage of disorders evidences in B-scan images, but this delineation is not always optimum and requires complex additional processing stages. This work proposes an optimized delineation of degraded spots in vessel walls, robust to noisy environments, based on the analysis of the second order variation of image intensity of backreflection to determine the type of local structure. Results improve the delineation of wall anomalies providing a deeper physiological perception of the vessel wall conditions. Achievements could be also transferred to other clinical scenarios: carotid arteries, aorto-iliac or ilio-femoral sections, intracranial, etc.

Transposition of the Greater Arteries (TGA)

MedlinePlus

... Heart Disease Diseases of the arteries, valves, and aorta, as well as cardiac rhythm disturbances Aortic Valve ... Transposition of the Great Arteries Coarctation of the Aorta Truncus Arteriosus Single Ventricle Defects Patent Ductus Arteriosus ...

Facts about Hypoplastic Left Heart Syndrome

MedlinePlus

... Septal Defect Atrioventricular Septal Defect Coarctation of the Aorta D-Transposition of the Great Arteries Hypoplastic Left ... is very small. The ascending portion of the aorta is underdeveloped or is too small. Often, babies ...

Genetics Home Reference: Loeys-Dietz syndrome

MedlinePlus

... Dietz syndrome is characterized by enlargement of the aorta , which is the large blood vessel that distributes ... heart to the rest of the body. The aorta can weaken and stretch, causing a bulge in ...

Genetics Home Reference: critical congenital heart disease

MedlinePlus

... into and out of the heart (including the aorta and pulmonary artery). Still others involve a combination ... defects classified as CCHD include coarctation of the aorta , double-outlet right ventricle, D-transposition of the ...

Heart and Blood Vessels in Marfan Syndrome

MedlinePlus

... The most common of these problems affects the aorta, the main blood vessel carrying blood from the ... have problems in blood vessels other than the aorta. Even though heart and blood vessel problems affect ...

Analysis of Dynamic Geometric Configuration of the Aortic Channel from the Perspective of Tornado-Like Flow Organization of Blood Flow.

PubMed

Zhorzholiani, Sh T; Mironov, A A; Talygin, E A; Tsyganokov, Yu M; Agafonov, A M; Kiknadze, G I; Gorodkov, A Yu; Bokeriya, L A

2018-03-01

Analysis of the data of morphometry of aortic casts, aortography at different pressures, and multispiral computer tomography of the aorta with contrast and normal pulse pressure showed that geometric configuration of the flow channel of the aorta during the whole cardiac cycle corresponded to the conditions of self-organization of tornado-like quasipotential flow described by exact solutions of the Navier-Stokes equation and continuity of viscous fluid typical for this type of fluid flows. Increasing pressure in the aorta leads to a decrease in the degree of approximation of the channel geometry to the ratio of exact solution and increases the risk of distortions in the structure of the flow. A mechanism of evolution of tornado-like flow in the aorta was proposed.

Geodesic Distance Algorithm for Extracting the Ascending Aorta from 3D CT Images

PubMed Central

Jang, Yeonggul; Jung, Ho Yub; Hong, Youngtaek; Cho, Iksung; Shim, Hackjoon; Chang, Hyuk-Jae

2016-01-01

This paper presents a method for the automatic 3D segmentation of the ascending aorta from coronary computed tomography angiography (CCTA). The segmentation is performed in three steps. First, the initial seed points are selected by minimizing a newly proposed energy function across the Hough circles. Second, the ascending aorta is segmented by geodesic distance transformation. Third, the seed points are effectively transferred through the next axial slice by a novel transfer function. Experiments are performed using a database composed of 10 patients' CCTA images. For the experiment, the ground truths are annotated manually on the axial image slices by a medical expert. A comparative evaluation with state-of-the-art commercial aorta segmentation algorithms shows that our approach is computationally more efficient and accurate under the DSC (Dice Similarity Coefficient) measurements. PMID:26904151

Arteriosclerosis in the ventral aorta and epicarditis in the bulbus arteriosus of Atlantic salmon (Salmo salar L).

PubMed

Dalum, A S; Kristthorsdottir, K H; Griffiths, D J; Bjørklund, K; Poppe, T T

2017-06-01

Spontaneous mortality of seemingly healthy, farmed Atlantic salmon (Salmo salar L) is an increasing problem in Norwegian aquaculture. In this study, we present a morphological study of the previously undescribed syndrome of arteriosclerosis of the ventral aorta and epicarditis of the adjacent bulbus arteriosus found in farmed Atlantic salmon, with wild-captured fish as a control group. Both the ventral aorta and epicardium are vital for correct arterial compliance and vascular resistance in the respiratory capillaries of the gills. We discuss the possible implications of ventral aorta arteriosclerosis and epicarditis for blood vascular health and in particular for the increasing frequency of spontaneous gill bleeding in farmed salmon. As both these conditions primarily occur in farmed salmon, we suggest that they should be considered pathological. © 2016 John Wiley & Sons Ltd.

Ross procedure for ascending aortic replacement.

PubMed

Elkins, R C; Lane, M M; McCue, C

1999-06-01

Patients with aortic valve disease and aneurysm or dilatation of the ascending aorta require both aortic valve replacement and treatment of their ascending aortic disease. In children and young adults, the Ross operation is preferred when the aortic valve requires replacement, but the efficacy of extending this operation to include replacement of the ascending aorta or reduction of the dilated aorta has not been tested. We reviewed the medical records of 18 (5.9%) patients with aortic valve disease and an ascending aortic aneurysm and 26 (8.5%) patients with dilation of the ascending aorta, subgroups of 307 patients who had a Ross operation between August 1986 and February 1998. We examined operative and midterm results, including recent echocardiographic assessment of autograft valve function and ability of the autograft root and ascending aortic repair or replacement to maintain normal structural integrity. There was one operative death (2%) related to a perioperative stroke. Forty-two of 43 survivors have normal autograft valve function, with trace to mild autograft valve insufficiency, and one patient has moderate insufficiency at the most recent echocardiographic evaluation. None of the patients has dilatation of the autograft root or of the replaced or reduced ascending aorta. Early results with extension of the Ross operation to include replacement of an ascending aortic aneurysm or vertical aortoplasty for reduction of a dilated ascending aorta are excellent, with autograft valve function equal to that seen in similar patients without ascending aortic disease.

Fructose-rich diet induces gender-specific changes in expression of the renin-angiotensin system in rat heart and upregulates the ACE/AT1R axis in the male rat aorta.

PubMed

Bundalo, Maja M; Zivkovic, Maja D; Romic, Snjezana Dj; Tepavcevic, Snezana N; Koricanac, Goran B; Djuric, Tamara M; Stankovic, Aleksandra D

2016-01-01

The cardiovascular renin-angiotensin system (RAS) could be affected by gender and dietary regime. We hypothesized that male rats will be more susceptible to activation of RAS in the heart and aorta, as a response to a fructose-rich diet (FRD). Both male and female Wistar rats were given a 10% (w/v) fructose solution for 9 weeks. We measured the biochemical parameters, blood pressure (BP) and heart rate. We used Western blot and real-time polymerase chain reaction (PCR) to quantify protein and gene expression. In the male rats, the FRD elevated BP and expression of cardiac angiotensin-converting enzyme (ACE), while the expression of angiotensin-converting enzyme 2 (ACE2) and angiotensin II Type 2 receptor (AT2R) were significantly decreased. In female rats, there were no changes in cardiac RAS expression due to FRD. Furthermore, the ACE/AT1R axis was overexpressed in the FRD male rats' aortae, while only AT1R was upregulated in the FRD female rats' aortae. ACE2 expression remained unchanged in the aortae of both genders receiving the FRD. The FRD induced gender-specific changes in the expression of the RAS in the heart and aortae of male rats. Further investigations are required in order to get a comprehensive understanding of the underlying mechanisms of gender-specific fructose-induced cardiovascular pathologies. © The Author(s) 2016.

Fructose-rich diet induces gender-specific changes in expression of the renin–angiotensin system in rat heart and upregulates the ACE/AT1R axis in the male rat aorta

PubMed Central

Bundalo, Maja M; Zivkovic, Maja D; Romic, Snjezana Dj; Tepavcevic, Snezana N; Koricanac, Goran B; Djuric, Tamara M; Stankovic, Aleksandra D

2016-01-01

Introduction: The cardiovascular renin–angiotensin system (RAS) could be affected by gender and dietary regime. We hypothesized that male rats will be more susceptible to activation of RAS in the heart and aorta, as a response to a fructose-rich diet (FRD). Materials and methods: Both male and female Wistar rats were given a 10% (w/v) fructose solution for 9 weeks. We measured the biochemical parameters, blood pressure (BP) and heart rate. We used Western blot and real-time polymerase chain reaction (PCR) to quantify protein and gene expression. Results: In the male rats, the FRD elevated BP and expression of cardiac angiotensin-converting enzyme (ACE), while the expression of angiotensin-converting enzyme 2 (ACE2) and angiotensin II Type 2 receptor (AT2R) were significantly decreased. In female rats, there were no changes in cardiac RAS expression due to FRD. Furthermore, the ACE/AT1R axis was overexpressed in the FRD male rats’ aortae, while only AT1R was upregulated in the FRD female rats’ aortae. ACE2 expression remained unchanged in the aortae of both genders receiving the FRD. Conclusions: The FRD induced gender-specific changes in the expression of the RAS in the heart and aortae of male rats. Further investigations are required in order to get a comprehensive understanding of the underlying mechanisms of gender-specific fructose-induced cardiovascular pathologies. PMID:27121972

Microsurgical Bypass Training Rat Model, Part 1: Technical Nuances of Exposure of the Aorta and Iliac Arteries.

PubMed

Tayebi Meybodi, Ali; Lawton, Michael T; Mokhtari, Pooneh; Yousef, Sonia; Gandhi, Sirin; Benet, Arnau

2017-11-01

Animal models using rodents are frequently used for practicing microvascular anastomosis-an essential technique in cerebrovascular surgery. However, safely and efficiently exposing rat's target vessels is technically difficult. Such difficulty may lead to excessive hemorrhage and shorten animal survival. This limits the ability to perform multiple anastomoses on a single animal and may increase the overall training time and costs. We report our model for microsurgical bypass training in rodents in 2 consecutive articles. In part 1, we describe the technical nuances for a safe and efficient exposure of the rat abdominal aorta and common iliac arteries (CIAs) for bypass. Over a 2-year period, 50 Sprague-Dawley rats underwent inhalant anesthesia for practicing microvascular anastomosis on the abdominal aorta and CIAs. Lessons learned regarding the technical nuances of vessel exposure were recorded. Several technical nuances were important for avoiding intraoperative bleeding and preventing animal demise while preparing an adequate length of vessels for bypass. The most relevant technical nuances include (1) generous subcutaneous dissection; (2) use of cotton swabs for the blunt dissection of the retroperitoneal fat; (3) combination of sharp and blunt dissection to isolate the aorta and iliac arteries from the accompanying veins; (4) proper control of the posterior branches of the aorta; and (5) efficient division and mobilization of the left renal pedicle. Applying the aforementioned technical nuances enables safe and efficient preparation of the rat abdominal aorta and CIAs for microvascular anastomosis. Copyright © 2017 Elsevier Inc. All rights reserved.

Quantification of Regional Aortic Stiffness Using MR Elastography: A Phantom and Ex-vivo Porcine Aorta Study

PubMed Central

Zhang, Nan; Chen, Jun; Yin, Meng; Glaser, Kevin J.; Xu, Lei; Ehman, Richard L.

2015-01-01

MR Elastography (MRE) is a noninvasive technique for measuring tissue stiffness that has been used to assess the average stiffness of the abdominal aorta. The utility of aortic MRE would be improved if it could provide information about local variations in aortic stiffness. We hypothesize that regional variations in aortic stiffness can also be measured with MRE and the purpose of this work was to demonstrate that MRE can measure regional stiffness variations in a vascular phantom and in ex vivo porcine aortas. A vascular phantom was fabricated, containing two silicone tubes embedded in gel. A segment of one of the tubes was modified to increase its stiffness. MRE was performed on the phantom with a continuous flow of water through the tubes. The stiffness distribution along the modified tube was measured and compared to the reference tube. MRE was also performed in porcine aortas embedded in gel with segments treated with saline or formalin for 4 days. The stiffness difference between saline- and formalin-treated aortic segments was measured by MRE and mechanical tests. A positive correlation was found between the regional stiffnesses measured by MRE and mechanical tests. The results indicate that MRE can be used to evaluate the local stiffness distribution in silicone tubes and ex vivo porcine aortas. It may therefore be possible to apply MRE to measure regional stiffness variations of the aorta in vivo. PMID:26597836

Hypercholesterolemia Up-Regulates the Expression of Intermedin and Its Receptor Components in the Aorta of Rats via Inducing the Oxidative Stress.

PubMed

Meng, Qingtao; Shi, Di; Feng, Jiayue; Su, Yanling; Long, Yang; He, Sen; Wang, Si; Wang, Yong; Zhang, Xiangxun; Chen, Xiaoping

2016-01-01

Hypercholesterolemia can cause damage to the artery. Intermedin (IMD) is a novel member of the calcitonin gene-related peptide family. This study aims to investigate the aortic expression of IMD and its receptors in hypercholesterolemia without atherosclerosis. Male Wistar rats were fed with high cholesterol diet, with or without simvastatin and vitamin C. Both the malondialdehyde (MDA) and superoxide dismutase (SOD) in plasma and aorta were determined as the oxidative stress biomarkers. The plasma IMD was assessed by radioimmunoassay. Within the aorta, the mRNA expression of IMD along with its receptor components was determined, and the corresponding protein level of the CRLR/RAMPs was also assessed. The hypercholesterolemia rats without atherosclerotic lesion manifested a higher level of MDA and SOD and the plasma IMD elevated. Increased expression of IMD and all its receptor components (CRLR, RAMP1, RAMP2, and RAMP3) were displayed within the aorta. The simvastatin indirectly attenuated oxidative stress by improving lipid profiles, while the vitamin C directly reduced oxidative stress without interfering with the serum lipids. Both simvastatin and vitamin C ameliorated the aortic injury, decreased the plasma IMD level, and recovered the expression of IMD and its receptors within the aorta. The up-regulated expression of IMD is observed within the aorta of the hypercholesterolemia rats. In addition, the oxidative stress participates in the up-regulation. © 2016 by the Association of Clinical Scientists, Inc.

Mineralocorticoid receptor antagonism protects the aorta from vascular smooth muscle cell proliferation and collagen deposition in a rat model of adrenal aldosterone-producing adenoma.

PubMed

Yan, Yongji; Wang, Chao; Lu, Yiqin; Gong, Huijie; Wu, Zhun; Ma, Xin; Li, Hongzhao; Wang, Baojun; Zhang, Xu

2018-02-01

The number of patients with adrenal aldosterone-producing adenomas (APAs) has gradually increased. However, even after adenoma resection, some patients still suffer from high systolic blood pressure (SBP), which is possibly due to great arterial remodeling. Moreover, mineralocorticoid receptors (MRs) were found to be expressed in vascular smooth muscle cells (VSMCs). This study aims to determine whether MR antagonism protects the aorta from aldosterone-induced aortic remolding. Male rats were subcutaneously implanted with an osmotic minipumps and randomly divided into four groups: control; aldosterone (1 μg/h); aldosterone plus a specific MR antagonist, eplerenone (100 mg/kg/day); and aldosterone plus a vasodilator, hydralazine (25 mg/kg/day). After 8 weeks of infusion, aortic smooth muscle cell proliferation and collagen deposition, as well as the MDM2 and TGF-β1 expression levels in the aorta, were examined. Model rats with APAs were successfully constructed. Compared with the control rats, the model rats exhibited (1) marked SBP elevation, (2) no significant alteration in aortic morphology, (3) increased VSMC proliferation and MDM2 expression in the aorta, and (4) enhanced total collagen and collagen III depositions in the aorta, accompanied with up-regulated expression of TGF-β1. These effects were significantly inhibited by co-administration with eplerenone but not with hydralazine. These findings suggested that specific MR antagonism protects the aorta from aldosterone-induced VSMC proliferation and collagen deposition.

Customized CT angiogram planning for intraoperative transesophageal echography-guided endovascular exclusion of thoracic aorta penetrating ulcer.

PubMed

Piazza, Michele; Lupia, Mario; Grego, Franco; Antonello, Michele

2015-04-01

The technique is demonstrated in a 78-year-old man; the preoperative CT angiogram showed a descending thoracic aorta ulcer of 5.9 cm in maximum diameter and 3.8 cm longitudinal extension. A ZTEG-2P-36-127-PF (Cook Medical) single tubular endograft was planned to be deployed. From the preoperative CT angiogram we planned to land 4.7 cm above the midline of the descending thoracic aorta ulcer and 8.0 cm below. In the operating room, under radioscopic vision the centre of the transesophageal echography probe was used as marker to identify the correspondent midline of the descending thoracic aorta ulcer and a centimeter-sized pigtail catheter in the aorta was used to calculate the desired length above and below the ulcer midline. The endograft was introduced and placed in the desired position compared to the transesophageal echography probe and the catheter; under transesophageal echography vision the graft was finally deployed. The CT angiogram at 1 month showed the correct endograft position, descending thoracic aorta ulcer exclusion with no signs of endoleak. In selected cases, this method allows planning in advance safe stent graft positioning and deployment totally assisted by transesophageal echography, with no risk of periprocedural contrast-related renal failure and reduced radiation exposure for the patient and operators. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Extracellular Matrix Disarray as A Mechanism for Greater Abdominal vs. Thoracic Aortic Stiffness with Aging in Primates

PubMed Central

Zhang, Jie; Zhao, Xin; Vatner, Dorothy E; McNulty, Tara; Bishop, Sanford; Sun, Zhe; Shen, You-Tang; Chen, Li; Meininger, Gerald A; Vatner, Stephen F

2016-01-01

Objective Increased vascular stiffness is central to the pathophysiology of aging, hypertension, diabetes and atherosclerosis. However, relatively few studies have examined vascular stiffness in both the thoracic and abdominal aorta with aging, despite major differences in anatomy, embryological origin and relation to aortic aneurysm. Approach and Results The two other unique features of this study were 1) to study young (9±1 years) and old (26±1 years) male monkeys, and 2) to study direct and continuous measurements of aortic pressure and thoracic and abdominal aortic diameters in conscious monkeys. As expected, aortic stiffness, β, was increased p<0.05, 2–3 fold, in old vs. young thoracic aorta, and augmented further with superimposition of acute hypertension with phenylephrine. Surprisingly, stiffness was not greater in old thoracic aorta than young abdominal aorta. These results can be explained in part by the collagen/elastin ratio, but more importantly, by disarray of collagen and elastin, which correlated best with vascular stiffness. However, vascular smooth muscle cell stiffness, was not different in thoracic vs. abdominal aorta in either young or old monkeys. Conclusions Thus, aortic stiffness increases with aging as expected, but the most severe increases in aortic stiffness observed in the abdominal aorta is novel, where values in young monkeys equaled, or even exceeded, values of thoracic aortic stiffness in old monkeys. These results can be explained by alterations in collagen/elastin ratio, but even more importantly by collagen and elastin disarray. PMID:26891739

Automated aortic calcification detection in low-dose chest CT images

NASA Astrophysics Data System (ADS)

Xie, Yiting; Htwe, Yu Maw; Padgett, Jennifer; Henschke, Claudia; Yankelevitz, David; Reeves, Anthony P.

2014-03-01

The extent of aortic calcification has been shown to be a risk indicator for vascular events including cardiac events. We have developed a fully automated computer algorithm to segment and measure aortic calcification in low-dose noncontrast, non-ECG gated, chest CT scans. The algorithm first segments the aorta using a pre-computed Anatomy Label Map (ALM). Then based on the segmented aorta, aortic calcification is detected and measured in terms of the Agatston score, mass score, and volume score. The automated scores are compared with reference scores obtained from manual markings. For aorta segmentation, the aorta is modeled as a series of discrete overlapping cylinders and the aortic centerline is determined using a cylinder-tracking algorithm. Then the aortic surface location is detected using the centerline and a triangular mesh model. The segmented aorta is used as a mask for the detection of aortic calcification. For calcification detection, the image is first filtered, then an elevated threshold of 160 Hounsfield units (HU) is used within the aorta mask region to reduce the effect of noise in low-dose scans, and finally non-aortic calcification voxels (bony structures, calcification in other organs) are eliminated. The remaining candidates are considered as true aortic calcification. The computer algorithm was evaluated on 45 low-dose non-contrast CT scans. Using linear regression, the automated Agatston score is 98.42% correlated with the reference Agatston score. The automated mass and volume score is respectively 98.46% and 98.28% correlated with the reference mass and volume score.

Cholesteryl ester transfer protein inhibition enhances endothelial repair and improves endothelial function in the rabbit.

PubMed

Wu, Ben J; Shrestha, Sudichhya; Ong, Kwok L; Johns, Douglas; Hou, Liming; Barter, Philip J; Rye, Kerry-Anne

2015-03-01

High-density lipoproteins (HDLs) can potentially protect against atherosclerosis by multiple mechanisms, including enhancement of endothelial repair and improvement of endothelial function. This study asks if increasing HDL levels by inhibiting cholesteryl ester transfer protein activity with the anacetrapib analog, des-fluoro-anacetrapib, enhances endothelial repair and improves endothelial function in New Zealand White rabbits with balloon injury of the abdominal aorta. New Zealand White rabbits received chow or chow supplemented with 0.07% or 0.14% (wt/wt) des-fluoro-anacetrapib for 8 weeks. Endothelial denudation of the abdominal aorta was carried out after 2 weeks. The animals were euthanized 6 weeks postinjury. Treatment with 0.07% and 0.14% des-fluoro-anacetrapib reduced cholesteryl ester transfer protein activity by 81±4.9% and 92±12%, increased plasma apolipoprotein A-I levels by 1.4±0.1-fold and 1.5±0.1-fold, increased plasma HDL-cholesterol levels by 1.8±0.2-fold and 1.9±0.1-fold, reduced intimal hyperplasia by 37±11% and 51±10%, and inhibited vascular cell proliferation by 25±6.1% and 35±6.7%, respectively. Re-endothelialization of the injured aorta increased from 43±6.7% (control) to 69±6.6% and 76±7.7% in the 0.07% and 0.14% des-fluoro-anacetrapib-treated animals, respectively. Aortic ring relaxation and guanosine 3',5'-cyclic monophosphate production in response to acetylcholine were also improved. Incubation of HDLs from the des-fluoro-anacetrapib-treated animals with human coronary artery endothelial cells increased cell proliferation and migration relative to control. These effects were abolished by knockdown of scavenger receptor-B1 and PDZ domain-containing protein 1 and by pharmacological inhibition of phosphatidylinositol-4,5-bisphosphate 3-kinase/Akt. Increasing HDL levels by inhibiting cholesteryl ester transfer protein reduces intimal thickening and regenerates functional endothelium in damaged New Zealand White rabbit aortas in an scavenger receptor-B1-dependent and phosphatidylinositol-4,5-bisphosphate 3-kinase/Akt-dependent manner. © 2015 American Heart Association, Inc.

Decreased mitochondrial respiration in aneurysmal aortas of Fibulin-4 mutant mice is linked to PGC1A regulation.

PubMed

van der Pluijm, I; Burger, J; van Heijningen, P M; IJpma, A; van Vliet, N; Milanese, C; Schoonderwoerd, K; Sluiter, W; Ringuette, L J; Dekkers, D H W; Que, I; Kaijzel, E L; Te Riet, L; MacFarlane, E; Das, D; van der Linden, R; Vermeij, M; Demmers, J A; Mastroberardino, P G; Davis, E C; Yanagisawa, H; Dietz, H; Kanaar, R; Essers, J

2018-06-21

Thoracic aortic aneurysms are a life-threatening condition often diagnosed too late. To discover novel robust biomarkers, we aimed to better understand the molecular mechanisms underlying aneurysm formation. In Fibulin-4R/R mice, the extracellular matrix protein Fibulin-4 is 4-fold reduced, resulting in progressive ascending aneurysm formation and early death around 3 months of age. We performed proteomics and genomics studies on Fibulin-4R/R mouse aortas. Intriguingly, we observed alterations in mitochondrial protein composition in Fibulin-4R/R aortas. Consistently, functional studies in Fibulin-4R/R vascular smooth muscle cells (VSMCs) revealed lower oxygen consumption rates, but increased acidification rates. Yet, mitochondria in Fibulin-4R/R VSMCs showed no aberrant cytoplasmic localization. We found similar reduced mitochondrial respiration in Tgfbr-1M318R/+ VSMCs, a mouse model for Loeys-Dietz syndrome. Interestingly, also human fibroblasts from Marfan (FBN1) and Loeys-Dietz syndrome (TGFBR2 and SMAD3) patients showed lower oxygen consumption. While individual mitochondrial complex I-V activities were unaltered in Fibulin-4R/R heart and muscle, these tissues showed similar decreased oxygen consumption. Furthermore, aortas of aneurysmal Fibulin-4R/R mice displayed increased ROS levels. Consistent with these findings, gene expression analyses revealed dysregulation of metabolic pathways. Accordingly, blood ketone levels of Fibulin-4R/R mice were reduced and liver fatty acids were decreased, while liver glycogen was increased, indicating dysregulated metabolism at the organismal level. As predicted by gene expression analysis, the activity of PGC1α, a key regulator between mitochondrial function and organismal metabolism, was downregulated in Fibulin-4R/R VSMCs. Increased TGFβ reduced PGC1α levels, indicating involvement of TGFβ signalling in PGC1α regulation. Activation of PGC1α restored the decreased oxygen consumption in Fibulin-4R/R VSMCs and improved their reduced growth potential, emphasizing the importance of this key regulator. Our data indicate altered mitochondrial function and metabolic dysregulation, leading to increased ROS levels and altered energy production, as a novel mechanism, which may contribute to thoracic aortic aneurysm formation.

Evaluation of TGF beta1 expression and comparison the thickness of different aorta layers in experimental diabetes.

PubMed

Cuce, G; Kalkan, S S; Esen, H H

2011-01-01

It was aimed to investigate the effects of experimental diabetes on TGF beta1 expression and tunica intima and media thickness in abdominal and thoracic aorta. Fourteen three months old female rats were divided into two groups, non-diabetic and streptozotocin (STZ) induced diabetic group. Hematoxylin-Eosin and Verhoeff's Van Gieson elastic staining and TGF beta1 immunohistochemistry staining were performed. Abdominal and thoracic intima and media thickness of aortas were measured with the oculometer. Evaluation of intima and media thickness measurements showed no significant statistical differences between non-diabetic and diabetic groups. TGF beta1 expression increased significantly in thoracic diabetic (TD) group. The 60 day duration of diabetes is not sufficiently enough time for the development of pathological changes that could lead to thickening in aortic intima-media layers. TGF beta1 expression was negative in the abdominal aorta that can predispose to the development of atherosclerosis, which could develop overtime. This finding may be interpreted as an appropriate basis for the development of atherosclerosis. In the thoracic aorta TGF beta1 may coordinate cellular events such as tissue repair (Fig. 5, Ref. 23).

Vocal cord paralysis after surgery to the descending thoracic aorta via left posterolateral thoracotomy.

PubMed

Ohta, Noriyuki; Mori, Takahiko

2007-11-01

Vocal cord paralysis is one of the frequently encountered complications after aortic surgery. However, reports of vocal cord paralysis after aortic surgery have been limited. In a retrospective cohort study of vocal cord paralysis after aortic surgery at a general hospital, we sought factors related to its development after aortic surgery to the descending thoracic aorta via left posterolateral thoracotomy. We reviewed data for a total of 69 patients who, between 1989 and 1995, underwent aortic surgery to the descending thoracic aorta. We assessed factors associated with the development of vocal cord paralysis and postoperative complications. Postoperative vocal cord paralysis appeared in 19 patients. Multiple logistic regression analysis revealed two risk factors for vocal cord paralysis: chronic dilatation of the aorta at the left subclavian artery (odds ratio = 8.67) and anastomosis proximal to the left subclavian artery (odds ratio = 17.7). The duration of mechanical ventilation was significantly prolonged for patients with vocal cord paralysis. Certain surgical factors associated with left subclavian artery increase the risk of vocal cord paralysis after surgery on the descending thoracic aorta. Vocal cord paralysis after aortic surgery did not increase aspiration pneumonia but was associated with pulmonary complications.

The influence of the aortic valve angle on the hemodynamic features of the thoracic aorta

NASA Astrophysics Data System (ADS)

Ha, Hojin; Kim, Guk Bae; Kweon, Jihoon; Lee, Sang Joon; Kim, Young-Hak; Kim, Namkug; Yang, Dong Hyun

2016-08-01

Since the first observation of a helical flow pattern in aortic blood flow, the existence of helical blood flow has been found to be associated with various pathological conditions such as bicuspid aortic valve, aortic stenosis, and aortic dilatation. However, an understanding of the development of helical blood flow and its clinical implications are still lacking. In our present study, we hypothesized that the direction and angle of aortic inflow can influence helical flow patterns and related hemodynamic features in the thoracic aorta. Therefore, we investigated the hemodynamic features in the thoracic aorta and various aortic inflow angles using patient-specific vascular phantoms that were generated using a 3D printer and time-resolved, 3D, phase-contrast magnetic resonance imaging (PC-MRI). The results show that the rotational direction and strength of helical blood flow in the thoracic aorta largely vary according to the inflow direction of the aorta, and a higher helical velocity results in higher wall shear stress distributions. In addition, right-handed rotational flow conditions with higher rotational velocities imply a larger total kinetic energy than left-handed rotational flow conditions with lower rotational velocities.

The influence of the aortic valve angle on the hemodynamic features of the thoracic aorta.

PubMed

Ha, Hojin; Kim, Guk Bae; Kweon, Jihoon; Lee, Sang Joon; Kim, Young-Hak; Kim, Namkug; Yang, Dong Hyun

2016-08-26

Since the first observation of a helical flow pattern in aortic blood flow, the existence of helical blood flow has been found to be associated with various pathological conditions such as bicuspid aortic valve, aortic stenosis, and aortic dilatation. However, an understanding of the development of helical blood flow and its clinical implications are still lacking. In our present study, we hypothesized that the direction and angle of aortic inflow can influence helical flow patterns and related hemodynamic features in the thoracic aorta. Therefore, we investigated the hemodynamic features in the thoracic aorta and various aortic inflow angles using patient-specific vascular phantoms that were generated using a 3D printer and time-resolved, 3D, phase-contrast magnetic resonance imaging (PC-MRI). The results show that the rotational direction and strength of helical blood flow in the thoracic aorta largely vary according to the inflow direction of the aorta, and a higher helical velocity results in higher wall shear stress distributions. In addition, right-handed rotational flow conditions with higher rotational velocities imply a larger total kinetic energy than left-handed rotational flow conditions with lower rotational velocities.

The influence of the aortic valve angle on the hemodynamic features of the thoracic aorta

PubMed Central

Ha, Hojin; Kim, Guk Bae; Kweon, Jihoon; Lee, Sang Joon; Kim, Young-Hak; Kim, Namkug; Yang, Dong Hyun

2016-01-01

Since the first observation of a helical flow pattern in aortic blood flow, the existence of helical blood flow has been found to be associated with various pathological conditions such as bicuspid aortic valve, aortic stenosis, and aortic dilatation. However, an understanding of the development of helical blood flow and its clinical implications are still lacking. In our present study, we hypothesized that the direction and angle of aortic inflow can influence helical flow patterns and related hemodynamic features in the thoracic aorta. Therefore, we investigated the hemodynamic features in the thoracic aorta and various aortic inflow angles using patient-specific vascular phantoms that were generated using a 3D printer and time-resolved, 3D, phase-contrast magnetic resonance imaging (PC-MRI). The results show that the rotational direction and strength of helical blood flow in the thoracic aorta largely vary according to the inflow direction of the aorta, and a higher helical velocity results in higher wall shear stress distributions. In addition, right-handed rotational flow conditions with higher rotational velocities imply a larger total kinetic energy than left-handed rotational flow conditions with lower rotational velocities. PMID:27561388

Double-arterial cannulation for aortic valve replacement with porcelain aorta.

PubMed

De Paulis, Ruggero; Maselli, Daniele; Scaffa, Raffaele; Nardella, Saverio

2009-10-01

We describe a new technique of aortic valve replacement (AVR) in patients with porcelain aorta. Three patients (mean age 75 years) were treated. The cardiopulmonary bypass (CPB) was established after side-graft right axillary artery and direct femoral artery cannulation. Venous drainage was obtained by atrio-caval cannulation. The procedures were performed in mild hypothermia (30 degrees C). Cerebral perfusion was carried out by clamping the innominate artery and all epiaortic vessels. The aorta was endoclamped by a Foley balloon inserted into the isthmus. The aorta was then opened longitudinally for 10 cm to expose and replace the aortic valve. Near-infra-red spectroscopy (NIRS) and bilateral radial artery pressure were used to monitor effective cerebral perfusion. Operative mortality was absent. The mean time of CPB was 73 min. NIRS-derived tissue oxygenation was maintained above 55%. Postoperative course was uneventful. This technique has several advantages: first, the cannulation of right axillary and the common femoral artery allows simultaneous cerebral and systemic perfusion. Second, any form of cross-clamp is avoided and the aorta is occluded away from the epiaortic vessels. Third, there is an increased freedom to choose the best place for aortotomy.

High level cross of the esophagus with the descending aorta in scoliosis: CT study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takahashi, Koji; Kikuno, Motoyuki; Hyodoh, Hideki

1996-05-01

The esophagus occasionally crosses the descending aorta at an unusually high level (3-5 cm inferior to the carina) in right-sided scoliosis. The purpose of this study was to analyze the mechanism of this finding. We prospectively evaluated thoracic CT scans in 30 patients with right-sided scoliosis. We assessed the alterations in the positions of the esophagus and the descending aorta by the thoracic deformity. The descending aorta followed the scoliotic curve of the spine in 26 (87%) patients. The esophagus followed the scoliotic curve of the spine in 14 (47%) patients and did not in 16 (53%). The anteroposterior diametermore » of the thorax in the former group was significantly smaller than that in the latter (p < 0.01). High level cross of both structures was identified in 14 (47%) patients, and all of them belonged to the group in which the esophagus did not follow the scoliotic curve of the spine. The unusual high level cross of the esophagus with the descending aorta occasionally seen in scoliosis is due to a difference in the positional alterations of the two structures resulting from the scoliosis. 6 refs., 3 figs.« less

Anomalous left coronary artery from the pulmonary artery

MedlinePlus

... begins from the pulmonary artery instead of the aorta. ALCAPA is present at birth (congenital) . Causes ALCAPA ... the normal heart, the LCA originates from the aorta. It supplies oxygen-rich blood to the heart ...

Aortic arch syndrome

MedlinePlus

... including: Congenital absence of a branch of the aorta Isolation of the subclavian arteries Vascular rings An ... Braverman AC. Diseases of the aorta. In: Bonow RO, Mann DL, Zipes DP, ... Heart Disease: A Textbook of Cardiovascular Medicine . 10th ...

Density of calcium in the ascending thoracic aorta and risk of incident cardiovascular disease events.

PubMed

Thomas, Isac C; McClelland, Robyn L; Michos, Erin D; Allison, Matthew A; Forbang, Nketi I; Longstreth, W T; Post, Wendy S; Wong, Nathan D; Budoff, Matthew J; Criqui, Michael H

2017-10-01

The volume and density of coronary artery calcium (CAC) both independently predict cardiovascular disease (CVD) beyond standard risk factors, with CAC density inversely associated with incident CVD after accounting for CAC volume. We tested the hypothesis that ascending thoracic aorta calcium (ATAC) volume and density predict incident CVD events independently of CAC. The Multi-Ethnic Study of Atherosclerosis (MESA) is a prospective cohort study of participants without clinical CVD at baseline. ATAC and CAC were measured from baseline cardiac computed tomography (CT). Cox regression models were used to estimate the associations of ATAC volume and density with incident coronary heart disease (CHD) events and CVD events, after adjustment for standard CVD risk factors and CAC volume and density. Among 6811 participants, 234 (3.4%) had prevalent ATAC and 3395 (49.8%) had prevalent CAC. Over 10.3 years, 355 CHD and 562 CVD events occurred. One-standard deviation higher ATAC density was associated with a lower risk of CHD (HR 0.48 [95% CI 0.29-0.79], p<0.01) and CVD (HR 0.56 [0.37-0.84], p<0.01) after full adjustment. ATAC volume was not associated with outcomes after full adjustment. ATAC was uncommon in a cohort free of clinical CVD at baseline. However, ATAC density was inversely associated with incident CHD and CVD after adjustment for CVD risk factors and CAC volume and density. Copyright © 2017 Elsevier B.V. All rights reserved.

Single coronary artery with bicuspid aortic valve stenosis and aneurysm of the ascending aorta: report of a case.

PubMed

Ishida, Narihiro; Shimabukuro, Katsuya; Matsuno, Yukihiro; Ogura, Hiroki; Takemura, Hirofumi

2014-03-01

A 73-year-old man with a severely stenosed bicuspid valve and an aneurysm of the ascending aorta underwent valve and aortic surgery. Preoperative imaging revealed a single coronary artery arising from the right side of the sinus of Valsalva and a branch that perfused into the left side of the heart to pass through the front of the pulmonary artery. We replaced the aortic valve and ascending aorta, painstakingly avoiding damage to the coronary artery and obstruction of the sole coronary ostium.

[Evaluation of the invasion of esophageal cancer to the aorta by cine-MR imaging].

PubMed

Kawahara, I; Nishimura, H; Uchida, M; Ueda, H; Fujimoto, K; Meno, S; Hayabuchi, N; Fujita, H

1993-01-25

We examined the usefulness of cine-MR imaging for evaluation of the invasion of esophageal cancer to the aorta in 12 cases. We used the technique of field echo pulse sequence. When the low intensity stripe was recognized between the tumor and the wall of aorta, we interpreted it as negative finding of the direct tumor invasion. By using this criteria, 11 of the 12 cases (92%) of the esophageal cancer for aortic wall invasion were correctly diagnosed as compared with 75% correct diagnosis by conventional MR imaging.

Morphological analysis of the hagfish heart. I. The ventricle, the arterial connection and the ventral aorta.

PubMed

Icardo, José M; Colvee, Elvira; Schorno, Sarah; Lauriano, Eugenia R; Fudge, Douglas S; Glover, Chris N; Zaccone, Giacomo

2016-03-01

We have studied the heart in three species of hagfish: Myxine glutinosa, Eptatretus stoutii, and Eptatretus cirrhatus and report about the morphology of the ventricle, the arterial connection and the ventral aorta. On the whole, the hagfish heart lacks outflow tract components, the ventricle and atrium adopt a dorso-caudal rather than a ventro-dorsal relationship, and the sinus venosus opens into the left side of the atrium. This may indicate a "defective" cardiac looping during embryogenesis. The ventral aorta is elongated in M. glutinosa and E. stoutii but sac-like in E. cirrhatus. The ventricles are entirely trabeculated. The myocytes show a low myofibrillar content and junctional complexes formed by fascia adherens and desmosomes. Gap junctions could not be demonstrated. Myocardial cells in M. glutinosa contain numerous lipid droplets. These droplets are less numerous in E. stoutii and practically absent in E. cirrhatus, suggesting different metabolic requirements. Other cell types present in the ventricle are chromaffin cells and granular leukocytes that contain rod-shaped granules. The ventricle-aorta connection is guarded by a bicuspid valve with left and right, pocket-like leaflets. The leaflets extend from the cranial end of the ventricle into the aorta but the junction is asymmetrical. This junction contains a ganglion-like structure in E. cirrhatus. The ventral aorta shows endothelial, media, and adventitial layers. The media contains smooth muscle cells surrounded by dense bands formed by tightly-packed extracellular filaments. In addition, a short number of elastic fibers are observed in M. glutinosa and E. stoutii. Cellular and extracellular elements are more loosely organized in the aorta of E. cirrhatus. The collagenous adventitia contains ganglion-like cells in the three species. In the absence of nerves, chromaffin and ganglion-like cells may control the activity of the myocardium and that of the aortic smooth muscle cells, respectively. © 2015 Wiley Periodicals, Inc.

Trans-apical aortic valve implantation in patients with severe calcification of the ascending aorta.

PubMed

Buz, Semih; Pasic, Miralem; Unbehaun, Axel; Drews, Thorsten; Dreysse, Stephan; Kukucka, Marian; Mladenow, Alexander; Hetzer, Roland

2011-08-01

In patients with calcification of the ascending aorta, postoperative stroke and mortality rates remain high after conventional aortic valve replacement, but the results of trans-apical aortic valve implantation in these patients are not known. We evaluate the outcome of trans-apical aortic valve implantation in patients with severely calcified ascending aorta in a single center with expanded procedural experience. Between April 2008 and July 2010, 258 patients underwent trans-apical aortic valve implantation using Edwards Sapien valve. By computed tomography (CT) scan, we identified 46 (18%) patients with severe calcification of the ascending aorta (16 with porcelain aorta and 30 with severe, but not complete, calcification). Of 46 patients (mean age 77 ± 10 years, range 63-90 years; EuroSCORE (European System for Cardiac Operative Risk Evaluation) 45 ± 22%; STS (Society of Thoracic Surgeons) score 23 ± 13) with calcified aorta, 15 received 23-mm valves and 31 patients 26-mm valves. Primary valve implantation was successful in 44 patients and a second valve was implanted (valve-in-valve) in two. Six patients underwent concomitant interventions (three elective percutaneous coronary intervention (PCI), one off-pump coronary artery bypass (OPCAB), one tricuspid valve reconstruction, and one left-ventricular (LV) aneurysmectomy). The final procedural results showed valve incompetence (trace or grade 1) in 17 (37%) patients and paravalvular leak in 15 (32.6%) (trace in 10 and grade 1 in five). There was no 30-day mortality. Postoperatively, cranial CT showed new cerebral ischemia areas in three patients (6.2%), but only one patient (2.1%) experienced postoperative neurological deficit (temporary aphasia). Survival at 6 and 12 months was 88% and 85.2%, respectively. Trans-apical aortic valve implantation can be performed safely in patients with aortic valve stenosis and severe calcification of the ascending aorta. Copyright © 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

Talk to Your Doctor about Abdominal Aortic Aneurysm

MedlinePlus

... problems with blood vessels) What is AAA? The aorta (“ay-OAR-tah”) is your body’s main artery. ... tube) that carries blood from your heart. The aorta carries blood from your heart to your abdomen, ...

Aortic microcalcification is associated with elastin fragmentation in Marfan syndrome.

PubMed

Wanga, Shaynah; Hibender, Stijntje; Ridwan, Yanto; van Roomen, Cindy; Vos, Mariska; van der Made, Ingeborg; van Vliet, Nicole; Franken, Romy; van Riel, Luigi Amjg; Groenink, Maarten; Zwinderman, Aeilko H; Mulder, Barbara Jm; de Vries, Carlie Jm; Essers, Jeroen; de Waard, Vivian

2017-11-01

Marfan syndrome (MFS) is a connective tissue disorder in which aortic rupture is the major cause of death. MFS patients with an aortic diameter below the advised limit for prophylactic surgery (<5 cm) may unexpectedly experience an aortic dissection or rupture, despite yearly monitoring. Hence, there is a clear need for improved prognostic markers to predict such aortic events. We hypothesize that elastin fragments play a causal role in aortic calcification in MFS, and that microcalcification serves as a marker for aortic disease severity. To address this hypothesis, we analysed MFS patient and mouse aortas. MFS patient aortic tissue showed enhanced microcalcification in areas with extensive elastic lamina fragmentation in the media. A causal relationship between medial injury and microcalcification was revealed by studies in vascular smooth muscle cells (SMCs); elastin peptides were shown to increase the activity of the calcification marker alkaline phosphatase (ALP) and reduce the expression of the calcification inhibitor matrix GLA protein in human SMCs. In murine Fbn1 C1039G/+ MFS aortic SMCs, Alpl mRNA and activity were upregulated as compared with wild-type SMCs. The elastin peptide-induced ALP activity was prevented by incubation with lactose or a neuraminidase inhibitor, which inhibit the elastin receptor complex, and a mitogen-activated protein kinase kinase-1/2 inhibitor, indicating downstream involvement of extracellular signal-regulated kinase-1/2 (ERK1/2) phosphorylation. Histological analyses in MFS mice revealed macrocalcification in the aortic root, whereas the ascending aorta contained microcalcification, as identified with the near-infrared fluorescent bisphosphonate probe OsteoSense-800. Significantly, microcalcification correlated strongly with aortic diameter, distensibility, elastin breaks, and phosphorylated ERK1/2. In conclusion, microcalcification co-localizes with aortic elastin degradation in MFS aortas of humans and mice, where elastin-derived peptides induce a calcification process in SMCs via the elastin receptor complex and ERK1/2 activation. We propose microcalcification as a novel imaging marker to monitor local elastin degradation and thus predict aortic events in MFS patients. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Teng, Cheming; Yu, Sheumeei; Chen, Chienchih

Magnolol is an antiplatelet agent isolated from Chinese herb Magnolia officinalis. It inhibited norepinephrine-induced phasic and tonic contractions in rat thoracic aorta. At the plateau of the NE-induced tonic contraction, addition of magnolol caused two phases (fast and slow) of relaxation. These two relaxations were concentration-dependent, and were not inhibited by indomethacin. The fast relaxation was completely antagonized by hemoglobin and methylene blue, and disappeared in de-endothelialized aorta while the slow relaxation was not affected by the above treatments. Magnolol also inhibited high potassium-induced, calcium-dependent contraction of rat aorta in a concentration-dependent manner. {sup 45}Ca{sup ++} influx induced by highmore » potassium or NE was markedly inhibited by magnolol. Cyclic GMP, but not PGI{sub 2}, was increased by magnolol in intact, but not in de-endothelialized aorta. It is concluded that magnolol relaxed vascular smooth muscle by releasing endothelium-derived relaxing factor (EDRF) and by inhibiting calcium influx through voltage-gated calcium channels.« less

ELASTIN: DIMINISHED REACTIVITY WITH ALDEHYDE REAGENTS IN COPPER DEFICIENCY AND LATHYRISM

PubMed Central

Miller, E. J.; Fullmer, Harold M.

1966-01-01

Elastin fibers in the aortas of control, lathyritic, copper-supplemented, and copper-deficient chicks were examined histochemically and chemically for aldehyde content. Diminished staining for aldehydes was obtained in the fibers from the aortas of lathyritic and copper-deficient chicks. Chemical studies of elastin isolated from the aortas of control and lathyritic chicks showed an apparent loss of lysine residues in control elastin to be associated with an increase in aldehyde content providing evidence that lysine is converted to an aldehyde-containing intermediate during biosynthesis of desmosine and isodesmosine. Approximately 6 aldehyde groups were present for every 1000 amino acids in elastin isolated from the aortas of control animals, while the corresponding number in lathyritic elastin was 4. At least two types of aldehydes, saturated and α,β-unsaturated, appear to be associated with elastin, suggesting the presence of more than one intermediate between lysine and the desmosines. PMID:5941783

Click-coated, heparinized, decellularized vascular grafts

PubMed Central

Dimitrievska, Sashka; Cai, Chao; Weyers, Amanda; Balestrini, Jenna L.; Lin, Tylee; Sundaram, Sumati; Hatachi, Go; Spiegel, David A.; Kyriakides, Themis R.; Miao, Jianjun; Li, Guoyun; Niklason, Laura; Linhardt, Robert J.

2014-01-01

A novel method enabling the engineering of a dense and appropriately oriented heparin-containing layer on decellularized aortas has been developed. Amino groups of decellularized aortas were first modified to azido groups using 3-azidobenzoic acid. Azide-clickable dendrons were attached onto the azido groups through “alkyne-azide” click chemistry, affording a ten-fold amplification of adhesions sites. Dendron end groups were finally decorated with end-on modified heparin chains. Heparin chains were oriented like heparan sulfate groups on native endothelial cells surface. XPS, NMR, MS and FTIR were used to characterize the synthesis steps, building the final heparin layered coatings. Continuity of the heparin coating was verified using fluorescent microscopy and histological analysis. Efficacy of heparin linkage was demonstrated with factor Xa antithrombogenic assay and platelet adhesion studies. The results suggest that oriented heparin immobilization to decellularized aortas may improve the in vivo blood compatibility of decellularized aortas and vessels. PMID:25463496

Tenascin C protects aorta from acute dissection in mice

PubMed Central

Kimura, Taizo; Shiraishi, Kozoh; Furusho, Aya; Ito, Sohei; Hirakata, Saki; Nishida, Norifumi; Yoshimura, Koichi; Imanaka-Yoshida, Kyoko; Yoshida, Toshimichi; Ikeda, Yasuhiro; Miyamoto, Takanobu; Ueno, Takafumi; Hamano, Kimikazu; Hiroe, Michiaki; Aonuma, Kazutaka; Matsuzaki, Masunori; Imaizumi, Tsutomu; Aoki, Hiroki

2014-01-01

Acute aortic dissection (AAD) is caused by the disruption of intimomedial layer of the aortic walls, which is immediately life-threatening. Although recent studies indicate the importance of proinflammatory response in pathogenesis of AAD, the mechanism to keep the destructive inflammatory response in check is unknown. Here, we report that induction of tenascin-C (TNC) is a stress-evoked protective mechanism against the acute hemodynamic and humoral stress in aorta. Periaortic application of CaCl2 caused stiffening of abdominal aorta, which augmented the hemodynamic stress and TNC induction in suprarenal aorta by angiotensin II infusion. Deletion of Tnc gene rendered mice susceptible to AAD development upon the aortic stress, which was accompanied by impaired TGFβ signaling, insufficient induction of extracellular matrix proteins and exaggerated proinflammatory response. Thus, TNC works as a stress-evoked molecular damper to maintain the aortic integrity under the acute stress. PMID:24514259

[Vascular effect of extract from mulberry leaves and underlying mechanism].

PubMed

Xia, Man-Li; Gao, Qin; Zhou, Xin-Mei; Qian, Ling-Bo; Shen, Zhong-Hua; Jiang, Hui-di; Xia, Qiang

2007-01-01

To investigate the vascular activity of extract from mulberry leaves (EML) on rat thoracic aorta and the underlying mechanism. Isolated thoracic rings of Sprague-Dawley rats were mounted on the organ bath and the tension of the vessel was recorded. (1) EML produced a concentration-dependent vasorelaxation of aorta preconstricted by high K(+) (60 mmol/L) or 10(-6) mol/L phenylephrine (PE) in endothelium-intact and endothelium-denuded arteries. (2) EML at EC(50) concentration reduced the calcium dose-response curve. (3) After incubation of aorta with verapamil, EML induced vasocontraction of aorta preconstricted by PE, which was abolished by ruthenium red. The vascular effect of EML is biphasic, the vasorelaxation is greater than the vasocontraction. The vasorelaxation induced by EML may be mediated by inhibition of voltage-and receptor-dependent calcium channels in vascular smooth muscle cells, while the vasocontraction is via activation of ryanodine receptor in endoplasmic reticulum.

Rupture of the thoracic aorta associated with experimental Angiostrongylus vasorum infection in a dog

PubMed Central

Mozzer, L.R.; Lima, W.S.

2012-01-01

This note describes the sudden death of a dog by the rupture of the thoracic aorta caused by the presence of Angiostrongylus vasorum. A female mongrel canine with a history of weight loss and exhaustion died two hours after clinical examination. At necropsy, performed one hour after death, showed the presence of clotted blood in the thoracic cavity. Haemothorax was diagnosed. The thoracic aorta wall was thin, congested and an abnormal hole in the wall was detected approximately 0.5 cm from the entrance to the diaphragm. From clotted blood collected from the thoracic cavity, 224 first stage larvae (L1) and 15 adults of Angiostrongylus vasorum were recovered alive. Also, from a blood clot found in the aorta, four adult females and 47 L1 larvae were recovered alive. Possibly, this parasite was responsible for the aortic rupture and death of the animal. PMID:22550632

Rupture of the thoracic aorta associated with experimental Angiostrongylus vasorum infection in a dog.

PubMed

Mozzer, L R; Lima, W S

2012-05-01

This note describes the sudden death of a dog by the rupture of the thoracic aorta caused by the presence of Angiostrongylus vasorum. A female mongrel canine with a history of weight loss and exhaustion died two hours after clinical examination. At necropsy, performed one hour after death, showed the presence of clotted blood in the thoracic cavity. Haemothorax was diagnosed. The thoracic aorta wall was thin, congested and an abnormal hole in the wall was detected approximately 0.5 cm from the entrance to the diaphragm. From clotted blood collected from the thoracic cavity, 224 first stage larvae (L1) and 15 adults of Angiostrongylus vasorum were recovered alive. Also, from a blood clot found in the aorta, four adult females and 47 L1 larvae were recovered alive. Possibly, this parasite was responsible for the aortic rupture and death of the animal.

[Clinical and immunological study of the relationship of the digestive system chronic diseases and atherosclerosis in the basin of the abdominal aorta in elderly patients].

PubMed

Dolgushina, A I; Shaposhnik, I I; Volchegorskiĭ, I A

2014-01-01

Paper describes clinical and immunological study about the relationship between chronic diseases of the digestive system and atherosclerosis in the basin of the abdominal aorta in patients of elderly and senile age. There were revealed the structural and clinical features of the gastrointestinal tract diseases, depending on the extent of atherosclerosis in the basin of the abdominal aorta. Evaluation of the immune status included the determination of lymphocyte subpopulation composition, the functional state of neutrophils and cytokine levels. It is found that the progression of atherosclerosis in the basin of the abdominal aorta in patients of elderly and senile age with chronic diseases of the digestive system was accompanied by the activation of pro-inflammatory mechanisms of the immune system and the accompanying intensification of oxidative stress.

Stabilization of the Abdominal Aorta During the Cardiac Cycle with the Sac-Anchoring Nellix Device.

PubMed

Itoga, Nathan K; Suh, Ga-Young; Cheng, Christopher P

2018-06-09

The Nellix device uses polymer-filled endobags to stabilize the abdominal aortic aneurysm (AAA) sac which is described as endovascular aneurysm sealing (EVAS). We analyzed cardiac-gated computed tomography angiography scans of repaired AAA with EVAS in 4 patients to evaluate the geometry and cardiac pulsatility-induced deformation. Graft translation and aortic curvature changes were found to be minimal during the cardiac cycle. The mean ± standard deviation changes in renal-aorta angles (1.0 ± 0.9°) were less than the changes in the superior mesenteric artery-aorta angle (4.0 ± 2.1°) (P < 0.01), during the cardiac cycle, demonstrating greater stabilization of the visceral branches closer to the device. These findings confirm stabilization of the abdominal aorta during the cardiac cycle using EVAS. Copyright © 2018 Elsevier Inc. All rights reserved.

Shape of the dilated aorta in children with bicuspid aortic valve

PubMed Central

Mart, Christopher R; McNerny, Bryn E

2013-01-01

Background: The dilated aorta in adults with bicuspid aortic valve has been shown to have different shapes, but it is not known if this occurs in children. This observational study was performed to determine if there are different shapes of the dilated aorta in children with bicuspid aortic valve and their association with age, gender, hemodynamic alterations, and degree of aortic enlargement. Methods: One hundred and eighty-seven echocardiograms done on pediatric patients (0 – 18 years) for bicuspid aortic valve, during 2008, were reviewed. Aortic valve morphology, shape/size of the aorta, and pertinent hemodynamic alterations were documented. Aortic dilation was felt to be present when at least one aortic segment had a z-score > 2.0; global aortic enlargement was determined by summing the aortic segment z-scores. The aortic shape was assessed by age, gender, valve morphology, and hemodynamic alterations. Results: Aortic dilation was present in 104/187 patients. The aorta had six different shapes designated from S1 through S6. There was no association between the aortic shape and gender, aortic valve morphology, or hemodynamic abnormalities. S3 was the most common after the age of six years and was associated with the most significant degree of global aortic enlargement. Conclusions: The shape of the dilated aorta in children with bicuspid aortic valve does not occur in a uniform manner and multiple shapes are seen. S2 and S3 are most commonly seen. As aortic dilation becomes more significant, a single shape (S3) becomes the dominant pattern. PMID:24688228

Intra- and inter-reader reproducibility of blood flow measurements on the ascending aorta and pulmonary artery using cardiac magnetic resonance.

PubMed

Di Leo, Giovanni; D'Angelo, Ida Daniela; Alì, Marco; Cannaò, Paola Maria; Mauri, Giovanni; Secchi, Francesco; Sardanelli, Francesco

2017-03-01

The aim of our study was to estimate the intra- and inter-reader reproducibility of blood flow measurements in the ascending aorta and main pulmonary artery using cardiac magnetic resonance (CMR) and a semi-automated segmentation method. The ethics committee approved this retrospective study. A total of 50 consecutive patients (35 males and 15 females; mean age±standard deviation 27±13 years) affected by congenital heart disease were reviewed. They underwent CMR for flow analysis of the ascending aorta and main pulmonary artery (1.5 T, through-plane phase-contrast sequences). Two independent readers (R1, trained radiology resident; R2, lower-trained technician student) obtained segmented images twice (>10-day interval), using a semi-automated method of segmentation. Peak velocity, forward and backward flows were obtained. Bland-Altman analysis was used and reproducibility was reported as complement to 100% of the ratio between the coefficient of repeatability and the mean. R1 intra-reader reproducibility for the aorta was 99% (peak velocity), 95% (forward flow) and 49% (backward flow); for the pulmonary artery, 99%, 91% and 90%, respectively. R2 intra-reader reproducibility was 92%, 91% and 38%; 98%, 86% and 87%, respectively. Inter-reader reproducibility for the aorta was 91%, 85% and 20%; for the pulmonary artery 96%, 75%, and 82%, respectively. Our results showed a good to excellent reproducibility of blood flow measurements of CMR together with a semiautomated method of segmentation, for all variables except the backward flow of the ascending aorta, with a limited impact of operator's training.

Endovascular Repair of Localized Pathological Lesions of the Descending Thoracic Aorta: Midterm Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Attia, Cherif; Villard, Jacques; Boussel, Loic

The endoluminal stent-graft represents an attractive and a less invasive technique for treatment of various diseases of the descending thoracic aorta. The purpose of this study was to evaluate the Talent endovascular stent-graft for the treatment of various localized diseases of the descending thoracic aorta. Over a 3-year period, Talent thoracic endografts were placed in 40 patients with a high surgical risk, presenting a localized lesion of the descending thoracic aorta: degenerative aneurysm (n = 13), acute traumatic rupture (n = 11), acute Stanford type B aortic dissection (n = 6), false aneurysm (n = 7), and penetrating atherosclerotic ulcermore » (n = 3). Fifteen patients (37.5%) were treated as emergencies. The feasibility of endovascular treatment and sizing of the aorta and stent-grafts were determined preoperatively by magnetic resonance angiography (MRA) and intraoperative angiography. Immediate and mid-term technical and clinical success was assessed by clinical and MRA follow-up. Endovascular treatment was completed successfully in all 40 patients, with no conversion to open repair or intraoperative mortality. The mean operative time was 37.5 {+-} 7 min. The overall 30-day mortality rate was 10% (n = 4), all in emergency cases, for causes not related to the endograft. The primary technical success was 92.5%. The mean follow-up period was 15 {+-} 5 months. The survival rate was 95% (n = 35). Diminution of the aneurismal size was observed in 47.5% (n = 19). We conclude that endovascular treatment of the various localized diseases of the descending thoracic aorta is a promising, feasible, alternative technique to open surgery in well-selected patients.« less

Aortic valve stenosis and aortic diameters determine the extent of increased wall shear stress in bicuspid aortic valve disease.

PubMed

Farag, Emile S; van Ooij, Pim; Planken, R Nils; Dukker, Kayleigh C P; de Heer, Frederiek; Bouma, Berto J; Robbers-Visser, Danielle; Groenink, Maarten; Nederveen, Aart J; de Mol, Bas A J M; Kluin, Jolanda; Boekholdt, S Matthijs

2018-02-16

Use of 4-dimensional flow magnetic resonance imaging (4D-flow MRI) derived wall shear stress (WSS) heat maps enables identification of regions in the ascending aorta with increased WSS. These regions are subject to dysregulation of the extracellular matrix and elastic fiber degeneration, which is associated with aortic dilatation and dissection. To evaluate the effect of the presence of aortic valve stenosis and the aortic diameter on the peak WSS and surface area of increased WSS in the ascending aorta. Prospective. In all, 48 bicuspid aortic valve (BAV) patients (38.1 ± 12.4 years) and 25 age- and gender-matched healthy individuals. Time-resolved 3D phase contrast MRI with three-directional velocity encoding at 3.0T. Peak systolic velocity, WSS, and aortic diameters were assessed in the ascending aorta and 3D heat maps were used to identify regions with elevated WSS. Comparisons between groups were performed by t-tests. Correlations were investigated by univariate and multivariate regression analysis. Elevated WSS was present in 15 ± 11% (range; 1-35%) of the surface area of the ascending aorta of BAV patients with aortic valve stenosis (AS) (n = 10) and in 6 ± 8% (range; 0-31%) of the ascending aorta of BAV patients without AS (P = 0.005). The mid-ascending aortic diameter negatively correlated with the peak ascending aortic WSS (R = -0.413, P = 0.004) and the surface area of elevated WSS (R = -0.419, P = 0.003). Multivariate linear regression analysis yielded that the height of peak WSS and the amount of elevated WSS depended individually on the presence of aortic valve stenosis and the diameter of the ascending aorta. The extent of increased WSS in the ascending aorta of BAV patients depends on the presence of aortic valve stenosis and aortic dilatation and is most pronounced in the presence of AS and a nondilated ascending aorta. 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018. © 2018 The Authors Journal of Magnetic Resonance Imaging published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine.

Aortic ruptures in seat belt wearers.

PubMed

Arajärvi, E; Santavirta, S; Tolonen, J

1989-09-01

Several investigations have indicated that rupture of the thoracic aorta is one of the leading causes of immediate death in victims of road traffic accidents. In Finland in 1983, 92% of front-seat passengers were seat belt wearers on highways and 82% in build-up areas. The mechanisms of rupture of the aorta have been intensively investigated, but the relationship between seat belt wearing and injury mechanisms leading to aortic rupture is still largely unknown. This study comprises 4169 fatally injured victims investigated by the Boards of Traffic Accident Investigation of Insurance Companies during the period 1972 to 1985. Chest injuries were recorded as the main cause of death in 1121 (26.9%) victims, 207 (5.0%) of those victims having worn a seat belt. Aortic ruptures were found at autopsy in 98 victims and the exact information of the location of the aortic tears was available in 68. For a control group, we analyzed 72 randomly chosen unbelted victims who had a fatal aortic rupture in similar accidents. The location of the aortic rupture in unbelted victims was more often in the ascending aorta, especially in drivers, whereas in seat belt wearers the distal descending aorta was statistically more often ruptured, especially in right-front passengers (p less than 0.05). The steering wheel predominated statistically as the part of the car estimated to have caused the injury in unbelted victims (37/72), and some interior part of the car was the most common cause of fatal thoracic impacts in seat belt wearers (48/68) (p less than 0.001). The mechanism of rupture of the aorta in the classic site just distal to the subclavian artery seems to be rapid deceleration, although complex body movements are also responsible in side impact collisions. The main mechanism leading to rupture of the ascending aorta seems to be severe blow to the bony thorax. This also often causes associated thoracic injuries, such as heart rupture and sternal fracture. Injuries in the ascending aorta were mostly found in unbelted victims and were sustained in frontal impact collisions, the injury-causing part of the car being the steering wheel. Ruptures of the distal descending part of the aorta were frequently associated with fractures of the thoracic vertebra.

Does the Position of the Aorta Change With the Altered Body Position in Ankylosing Spondylitis Patients With Thoracolumbar Kyphosis?: A Magnetic Resonance Imaging Investigation.

PubMed

Qu, Zhe; Bang-Ping, Qian; Qiu, Yong; Shi, Ben-Long; Ji, Ming-Liang; Wang, Bin; Yu, Yang; Zhu, Ze-Zhang

2017-08-01

A prospective magnetic resonance imaging study. To quantitatively explore the differences in the anatomic position of the aorta relative to the spine between supine and prone positions in ankylosing spondylitis (AS) patients with thoracolumbar kyphosis. Aortic complications may occur during the lumbar spine osteotomy in correcting thoracolumbar kyphosis secondary to AS, and a clear understanding of the spatial relationship between the aorta and the vertebrae is essential to prevent these iatrogenic complications. However, previous anatomic study was performed with AS patients in the supine position, which was different from the prone position adopted in surgery. To date, no report has been published to investigate the mobility of the aorta relative to the vertebrae between supine and prone positions in AS patients with thoracolumbar kyphosis. From March 2013 to September 2014, 22 AS patients (21 males, 1 female) with thoracolumbar kyphosis with a mean age of 30.7 years (range, 19-46 y) were recruited. Magnetic resonance imaging examinations from T9 to L3 in both the supine and prone positions were performed, and the left pedicle-aorta (LtP-Ao) angle and LtP-Ao distance were measured at each level. The differences of these parameters between the 2 positions were compared by the paired sample t test, and the relationships between the shifting of the aorta and the change of global kyphosis and lumbar lordosis were evaluated by the Pearson correlation coefficient. The level of significance (α) was set at 0.05. At T9-L3 levels, no significant difference was noted in LtP-Ao distances (43.78 vs. 44.42 mm; P=0.077) and LtP-Ao angles (0.82 vs. 0.22 degrees; P=0.053) between supine and prone positions. The correlation analysis also revealed no remarkable correlation between the change of LtP-Ao angle and increase of global kyphosis and lumbar lordosis in the prone position. There is no significant change of the relative positions between the aorta and the vertebrae at T9-L3 levels after the patient turned to a prone position, which implied that the mobility and range of motion of the aorta is limited in advanced stage of AS.

Exogenous BMP7 in aortae of rats with chronic uremia ameliorates expression of profibrotic genes, but does not reverse established vascular calcification

PubMed Central

Gravesen, Eva; Lerche Mace, Maria; Nordholm, Anders; Hofman-Bang, Jacob; Hruska, Keith; Haagen Nielsen, Carsten; Kjær, Andreas; Olgaard, Klaus

2018-01-01

Hyperphosphatemia and vascular calcification are frequent complications of chronic renal failure and bone morphogenetic protein 7 (BMP7) has been shown to protect against development of vascular calcification in uremia. The present investigation examined the potential reversibility of established uremic vascular calcification by treatment of uremic rats with BMP7. A control model of isogenic transplantation of a calcified aorta from uremic rats into healthy littermates examined whether normalization of the uremic environment reversed vascular calcification. Uremia and vascular calcification were induced in rats by 5/6 nephrectomy, high phosphate diet and alfacalcidol treatment. After 14 weeks severe vascular calcification was present and rats were allocated to BMP7, vehicle or aorta transplantation. BMP7 treatment caused a significant decrease of plasma phosphate to 1.56 ± 0.17 mmol/L vs 2.06 ± 0.34 mmol/L in the vehicle group even in the setting of uremia and high phosphate diet. Uremia and alfacalcidol resulted in an increase in aortic expression of genes related to fibrosis, osteogenic transformation and extracellular matrix calcification, and the BMP7 treatment resulted in a decrease in the expression of profibrotic genes. The total Ca-content of the aorta was however unchanged both in the abdominal aorta: 1.9 ± 0.6 μg/mg tissue in the vehicle group vs 2.2 ± 0.6 μg/mg tissue in the BMP7 group and in the thoracic aorta: 71 ± 27 μg/mg tissue in the vehicle group vs 54 ± 18 μg/mg tissue in the BMP7 group. Likewise, normalization of the uremic environment by aorta transplantation had no effect on the Ca-content of the calcified aorta: 16.3 ± 0.6 μg/mg tissue pre-transplantation vs 15.9 ± 2.3 μg/mg tissue post-transplantation. Aortic expression of genes directly linked to extracellular matrix calcification was not affected by BMP7 treatment, which hypothetically might explain persistent high Ca-content in established vascular calcification. The present results highlight the importance of preventing the development of vascular calcification in chronic kidney disease. Once established, vascular calcification persists even in the setting when hyperphosphatemia or the uremic milieu is abolished. PMID:29304096

Phenolics from Garcinia mangostana alleviate exaggerated vasoconstriction in metabolic syndrome through direct vasodilatation and nitric oxide generation.

PubMed

Abdallah, Hossam M; El-Bassossy, Hany M; Mohamed, Gamal A; El-Halawany, Ali M; Alshali, Khalid Z; Banjar, Zainy M

2016-09-13

Exaggerated vasoconstriction plays a very important role in the hypertension, a major component of metabolic syndrome (MetS). In the current work, the potential protective effect of methanol extract of fruit hulls of Garcinia mangostana L. on the exaggerated vasoconstriction in MetS has been investigated. In addition, the bioactive fraction and compounds as well as the possible mechanism of action have been illustrated. The effect of methanol extract of G. mangostana (GMT) fruit hulls on the vascular reactivity of aorta isolated from animals with MetS was investigated through bioassay-guided fractionation procedures. GMT was partitioned with chloroform (I) and the remaining mother liquor was fractionated on a Diaion HP-20 with H2O, 50 and 100 % methanol to give fractions II, III, and IV, respectively. The effect of total extract (GMT), bioactive fraction and the bioactive compounds on the vasoconstriction were examined in aortae isolated from animals with MetS by incubation for 30 min before exposing aortae to cumulative concentrations of phenylephrine (PE). The direct relaxant effect was also examined by adding cumulative concentrations of the bioactive fraction and its bioactive compounds to PE precontracted vessels. In addition, aortic nitric oxide (NO) and reactive oxygen species (ROS) production was investigated. Bioassay-guided fractionation of GMT revealed isolation of garcimangosone D (1), aromadendrin-8-C-β-D-glucopyranoside (2), 2,4,3'-trihydroxy benzophenone-6-O-β-D-glucopyranoside (3), maclurin-6-O-β-D-glucopyranoside (rhodanthenone) (4), epicatechin (5), and 2,3',4,5',6-pentahydroxy benzophenone (6). Only compounds 2, 4, and 5 significantly alleviated the exaggerated vasoconstriction of MetS aortae and in the same time showed significant vasodilation of PE pre-contracted aortae. To further illustrate the mechanism of action, the observed vasodilation was completely blocked by the nitric oxide (NO) synthase inhibitor, Nω-nitro-L-arginine methyl ester hydrochloride and inhibited by guanylate cyclase inhibitor, methylene blue. However, vasodilation was not affected by the potassium channel blocker, tetraethylammonium or the cyclooxygenase inhibitor, indomethacin. In addition, compounds 2, 4, and 5 stimulated NO generation from isolated aortae to levels comparable with acetylcholine. Furthermore, 4 and 5 inhibited reactive oxygen species generation in MetS aortae. The phenolic compounds 2, 4, and 5 ameliorated the exaggerated vasoconstriction in MetS aortae through vasodilatation-NO generation mechanism.

Ultrasonic Doppler measurement of renal artery blood flow

NASA Technical Reports Server (NTRS)

1974-01-01

Implantable pulsed Doppler ultrasonic flowmeter development has resulted in designs for application to the aortas of dogs and humans, and to human renal and coronary arteries. A figure of merit was derived for each design, indicating the degree of its precision. An H-array design for transcutaneous observation of blood flow was developed and tested in vitro. Two other simplified designs for the same purpose obviate the need to determine vessel orientation. One of these will be developed in the next time period. Techniques for intraoperative use and for implantation have had mixed success. While satisfactory on large vessels, higher ultrasonic frequencies and alteration of transducer design are required for satisfactory operation of pulsed Doppler flowmeters with small vessels.

Facts about dextro-Transposition of the Great Arteries (d-TGA)

MedlinePlus

... Septal Defect Atrioventricular Septal Defect Coarctation of the Aorta D-Transposition of the Great Arteries Hypoplastic Left ... the heart – the main pulmonary artery and the aorta – are switched in position, or “transposed.” What is ...

Flow visualisation study of spiral flow in the aorta-renal bifurcation.

PubMed

Fulker, David; Javadzadegan, Ashkan; Li, Zuming; Barber, Tracie

2017-10-01

The aim of this study was to analyse the flow dynamics in an idealised model of the aorta-renal bifurcation using flow visualisation, with a particular focus on the effect of aorta-to-renal flow ratio and flow spirality. The recirculation length was longest when there was low flow in the renal artery and smaller in the presence of spiral flow. The results also indicate that patients without spiral flow or who have low flow in the renal artery due to the presence of stenosis may be susceptible to heightened development of atherosclerotic lesions.

A successful retrograde re-entry at aorta using the Outback LTD catheter for a bilateral common iliac artery occlusion.

PubMed

Kim, Tae-Hoon; Ahn, Ji-Hun; Kim, Do-Hoi

2013-05-01

The Outback LTD re-entry catheter system has become a valuable tool for peripheral intervention and it has been widely used for variable peripheral chronic total occlusion (CTO). However, its use in the setting of the aorta was restricted because of concerns of bleeding risks resulting from re-entry puncture or ballooning. This report presents a case of successful re-entry using the Outback LTD Re-Entry Catheter (Cordis, Bridgewater, New Jersy) at the aorta in a patient with bilateral common iliac artery occlusion. Copyright © 2012 Wiley Periodicals, Inc.

JAG Tearing Technique with Radiofrequency Guide Wire for Aortic Fenestration in Thoracic Endovascular Aneurysm Repair

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ricci, Carmelo; Ceccherini, Claudio, E-mail: claudiocec@hotmail.it; Leonini, Sara

An innovative approach, the JAG tearing technique, was performed during thoracic endovascular aneurysm repair in a patient with previous surgical replacement of the ascending aorta with a residual uncomplicated type B aortic dissection who developed an aneurysm of the descending thoracic aorta with its lumen divided in two parts by an intimal flap. The proximal landing zone was suitable to place a thoracic stent graft. The distal landing zone was created by cutting the intimal flap in the distal third of the descending thoracic aorta with a radiofrequency guide wire and intravascular ultrasound catheter.

Intramural Hematoma of the Thoracic Aorta as a Form of Aortic Dissection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Juszkat, Robert; Pukacki, Fryderyk; Oszkinis, Grzegorz

Intramural hematoma (IMH) of the thoracic aorta is a complication with unknown etiology and a poorly predictable prognosis. There is also considerable controversy about the management and prognosis of IMH as well as the treatment. We present two cases of endovascular treatment of IMH with stent-graft placement. On the basis of references, we discuss risks of progression of the given pathology and possible complications. Despite the lack of uniform opinion about the management of this disorder, we present our observations of and experiences with endovascular treatment of IMH of the thoracic aorta.

CT Findings of Ruptured Intramural Hematoma of the Aorta Extending Along the Pulmonary Artery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sueyoshi, Eijun, E-mail: EijunSueyoshi@aol.com; Sakamoto, Ichiro; Uetani, Masataka

Mediastinal hematoma extending along the pulmonary artery is a rare complication of Stanford type A classic (double-barreled) aortic dissection. Rupture from the posterior aspect of the aortic root penetrates the shared adventitia of the aorta and pulmonary artery. From this location, hematoma can spread along the adventitial planes of the pulmonary arteries out into the lungs. We report a case of ruptured intramural hematoma of the aorta (IMH) extending along the pulmonary artery. To our knowledge, this finding in patients with IMH has not been reported in the literature.

Right Cervical Aortic Arch and Pseudocoarctation of the Aorta Associated with Aneurysms and Steal Phenomena: US, CTA, and MRA Findings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tanju, Sumru, E-mail: sumrutanju@yahoo.com; Ustuner, Evren; Erden, Ilhan

A 55-year-old woman presented with right cervical aortic arch with pseudocoarctation of the aorta further complicated by the presence of multiple aneurysms and a high-grade stenosis at the origin of the left subclavian trunk from the aorta causing a discrepancy in blood pressure between the right and left arms. The branching pattern and the resulting complex steal syndromes involving the left carotid and the subclavian system are unique. The computed tomography angiography, magnetic resonance angiography, and Doppler ultrasound findings are described.

Shaggy aorta syndrome after acute arterial macroembolism: report of a case.

PubMed

Hayashida, Naoki; Murayama, Hirokazu; Pearce, Yoko; Asano, Souichi; Ohashi, Yukio; Kohno, Hiroki; Handa, Takemi; Matsuo, Kozo; Nakagawa, Yasutsugu; Tatsuno, Katsuhiko

2004-01-01

We report the case of a patient who underwent treatment for a macroembolism in the right lower leg, which led to shaggy aorta syndrome. Anticoagulant therapy for the macroembolism and intra-aortic catheterization exacerbated the patient's renal function and triggered another massive microembolization of the visceral arteries, with a fatal outcome. To minimize the incremental complications inherent to this syndrome, awareness and prompt diagnosis with enhanced computed tomography or intravenous digital subtraction aortography are essential. Axillo-bifemoral bypass with bilateral external iliac artery ligations, performed with optimal timing, could save patients with shaggy aorta syndrome.

Feasibility of quantification of the distribution of blood flow in the normal human fetal circulation using CMR: a cross-sectional study.

PubMed

Seed, Mike; van Amerom, Joshua F P; Yoo, Shi-Joon; Al Nafisi, Bahiyah; Grosse-Wortmann, Lars; Jaeggi, Edgar; Jansz, Michael S; Macgowan, Christopher K

2012-11-26

We present the first phase contrast (PC) cardiovascular magnetic resonance (CMR) measurements of the distribution of blood flow in twelve late gestation human fetuses. These were obtained using a retrospective gating technique known as metric optimised gating (MOG). A validation experiment was performed in five adult volunteers where conventional cardiac gating was compared with MOG. Linear regression and Bland Altman plots were used to compare MOG with the gold standard of conventional gating. Measurements using MOG were then made in twelve normal fetuses at a median gestational age of 37 weeks (range 30-39 weeks). Flow was measured in the major fetal vessels and indexed to the fetal weight. There was good correlation between the conventional gated and MOG measurements in the adult validation experiment (R=0.96). Mean flows in ml/min/kg with standard deviations in the major fetal vessels were as follows: combined ventricular output (CVO) 540 ± 101, main pulmonary artery (MPA) 327 ± 68, ascending aorta (AAo) 198 ± 38, superior vena cava (SVC) 147 ± 46, ductus arteriosus (DA) 220 ± 39,pulmonary blood flow (PBF) 106 ± 59,descending aorta (DAo) 273 ± 85, umbilical vein (UV) 160 ± 62, foramen ovale (FO)107 ± 54. Results expressed as mean percentages of the CVO with standard deviations were as follows: MPA 60 ± 4, AAo37 ± 4, SVC 28 ± 7, DA 41 ± 8, PBF 19 ± 10, DAo50 ± 12, UV 30 ± 9, FO 21 ± 12. This study demonstrates how PC CMR with MOG is a feasible technique for measuring the distribution of the normal human fetal circulation in late pregnancy. Our preliminary results are in keeping with findings from previous experimental work in fetal lambs.

Scaffold-Free Tubular Tissues Created by a Bio-3D Printer Undergo Remodeling and Endothelialization when Implanted in Rat Aortae

PubMed Central

Itoh, Manabu; Nakayama, Koichi; Noguchi, Ryo; Kamohara, Keiji; Furukawa, Kojirou; Uchihashi, Kazuyoshi; Toda, Shuji; Oyama, Jun-ichi; Node, Koichi; Morita, Shigeki

2015-01-01

Background Small caliber vascular prostheses are not clinically available because synthetic vascular prostheses lack endothelial cells which modulate platelet activation, leukocyte adhesion, thrombosis, and the regulation of vasomotor tone by the production of vasoactive substances. We developed a novel method to create scaffold-free tubular tissue from multicellular spheroids (MCS) using a “Bio-3D printer”-based system. This system enables the creation of pre-designed three-dimensional structures using a computer controlled robotics system. With this system, we created a tubular structure and studied its biological features. Methods and Results Using a “Bio-3D printer,” we made scaffold-free tubular tissues (inner diameter of 1.5 mm) from a total of 500 MCSs (2.5× 104 cells per one MCS) composed of human umbilical vein endothelial cells (40%), human aortic smooth muscle cells (10%), and normal human dermal fibroblasts (50%). The tubular tissues were cultured in a perfusion system and implanted into the abdominal aortas of F344 nude rats. We assessed the flow by ultrasonography and performed histological examinations on the second (n = 5) and fifth (n = 5) day after implantation. All grafts were patent and remodeling of the tubular tissues (enlargement of the lumen area and thinning of the wall) was observed. A layer of endothelial cells was confirmed five days after implantation. Conclusions The scaffold-free tubular tissues made of MCS using a Bio-3D printer underwent remodeling and endothelialization. Further studies are warranted to elucidate the underlying mechanism of endothelialization and its function, as well as the long-term results. PMID:26325298

Pathophysiological levels of soluble P-selectin mediate adhesion of leukocytes to the endothelium through Mac-1 activation.

PubMed

Woollard, Kevin J; Suhartoyo, Andreas; Harris, Emma E; Eisenhardt, Steffen U; Jackson, Shaun P; Peter, Karlheinz; Dart, Anthony M; Hickey, Michael J; Chin-Dusting, Jaye P F

2008-11-07

Plasma soluble P-selectin (sP-selectin) levels are increased in pathologies associated with atherosclerosis, including peripheral arterial occlusive disease (PAOD). However, the role of sP-selectin in regulating leukocyte-endothelial adhesion is unclear. The aim of this study was to assess the ability of exogenous and endogenous sP-selectin to induce leukocyte responses that promote their adhesion to various forms of endothelium. In flow chamber assays, sP-selectin dose-dependently increased neutrophil adhesion to resting human iliac artery endothelial cells. Similarly, sP-selectin induced neutrophil adhesion to the endothelial surface of murine aortae and human radial venous segments in ex vivo flow chamber experiments. Using intravital microscopy to examine postcapillary venules in the mouse cremaster muscle, in vivo administration of sP-selectin was also found to significantly increase leukocyte rolling and adhesion in unstimulated postcapillary venules. Using a Mac-1-specific antibody and P-selectin knockout mouse, it was demonstrated that this finding was dependent on a contribution of Mac-1 to leukocyte rolling and endothelial P-selectin expression. This was confirmed in an ex vivo perfusion model using viable mouse aorta and human radial vessels. In contrast, with tumor necrosis factor-alpha-activated endothelial cells and intact endothelium, where neutrophil adhesion was already elevated, sP-selectin failed to further increase adhesion. Plasma samples from PAOD patients containing pathologically elevated concentrations of sP-selectin also increased neutrophil adhesion to the endothelium in a sP-selectin-dependent manner, as demonstrated by immunodepletion of sP-selectin. These studies demonstrate that raised plasma sP-selectin may influence the early progression of vascular disease by promoting leukocyte adhesion to the endothelium in PAOD, through Mac-1-mediated rolling and dependent on endothelial P-selectin expression.

Four Surgical Modifications to the Classic Elastase Perfusion Aneurysm Model Enable Haemodynamic Alterations and Extended Elastase Perfusion.

PubMed

Busch, Albert; Chernogubova, Ekaterina; Jin, Hong; Meurer, Felix; Eckstein, Hans-Henning; Kim, Mia; Maegdefessel, Lars

2018-04-24

Abdominal aortic aneurysm (AAA) is an individual and socioeconomic burden in today's ageing society. Treatment relies on surgical exclusion of the dilated aorta by open or endovascular repair. For research purposes, animal models are necessary and the elastase induced aneurysm model closely mimics end stage human aneurysm disease. To improve the translational value of this model, four modifications to the classic elastase perfusion procedure (PPE) in relation to human aneurysm morphology were conducted. In ten week old male C57BL/6J wild type mice the PPE procedure was modified in four ways using two different techniques. Flow alteration was simulated by partial ligation of the common iliac artery or the distal aorta. Additionally, careful exploration of the abdominal aortic branches allowed PPE induction at the suprarenal and iliac level. Molecular biology, ultrasound, and immunohistochemistry were used to evaluate these pilot results. Two aortic outflow obstructions simulating distal aortic or iliac stenosis significantly increase murine AAA diameter (p = .046), and affect local vascular wall remodelling. Suprarenal aortic dissection allows a juxtarenal aneurysm to be induced, similar to the angiotensin II induced aneurysm model. A separate investigation for canonical activation of transforming growth factor β in the two embryonically distinct juxtarenal and infrarenal segments showed no distinct difference. Creating an aortoiliac bifurcated aneurysm completes the mimicry of human aneurysm morphology. The alteration of the classic PPE aneurysm by outflow modulation and further elastase perfusion to the juxtarenal and aortoiliac segment modifies morphology and diameter, and thus increases the translational value in future research. Copyright © 2018 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.

Comparison of in vitro flows past a mechanical heart valve in anatomical and axisymmetric aorta models

NASA Astrophysics Data System (ADS)

Haya, Laura; Tavoularis, Stavros

2017-06-01

Flow characteristics past a bileaflet mechanical heart valve were measured under physiological flow conditions in a straight tube with an axisymmetric expansion, similar to vessels used in previous studies, and in an anatomical model of the aorta. We found that anatomical features, including the three-lobed sinus and the aorta's curvature affected significantly the flow characteristics. The turbulent and viscous stresses were presented and discussed as indicators for potential blood damage and thrombosis. Both types of stresses, averaged over the two axial measurement planes, were significantly lower in the anatomical model than in the axisymmetric one. This difference was attributed to the lower height-to-width ratio and more gradual contraction of the anatomical aortic sinus. The curvature of the aorta caused asymmetries in the velocity and stress distributions during forward flow. Secondary flows resulting from the aorta's curvature are thought to have redistributed the fluid stresses transversely, resulting in a more homogeneous stress distribution in the anatomical aortic root than in the axisymmetric root. The results of this study demonstrate the importance of modelling accurately the aortic geometry in experimental and computational studies of prosthetic devices. Moreover, our findings suggest that grafts used for aortic root replacement should approximate as closely as possible the shape of the natural sinuses.

Hydroxytyrosol and its complex forms (secoiridoids) modulate aorta and heart proteome in healthy rats: Potential cardio-protective effects.

PubMed

Catalán, Úrsula; Rubió, Laura; López de Las Hazas, Maria-Carmen; Herrero, Pol; Nadal, Pedro; Canela, Núria; Pedret, Anna; Motilva, Maria-José; Solà, Rosa

2016-10-01

Hydroxytyrosol (HT) is the major phenolic compound in virgin olive oil (VOO) in both free and complex forms (secoiridoids; SEC). Proteomics of cardiovascular tissues such as aorta or heart represents a promising tool to uncover the mechanisms of action of phenolic compounds in healthy animals. Twelve female Wistar rats were separated into three groups: a standard diet and two diets supplemented in phenolic compounds (HT and SEC) adjusted to 5 mg/kg/day during 21 days. Proteomic analyses of aorta and heart tissues were performed by nano-LC and MS. Ingenuity Pathway Analysis was used to generate interaction networks. HT or SEC modulated aorta and heart proteome compared to the standard diet. The top-scored networks were related to Cardiovascular System. HT and SEC downregulated proteins related to proliferation and migration of endothelial cells and occlusion of blood vessels in aorta and proteins related to heart failure in heart tissue. SEC showed higher fold change values compared to HT, attributed to higher concentration of HT detected in heart tissue. Changes at proteomic level in cardiovascular tissues may partially account for the underlying mechanisms of VOO phenols cardiovascular protection being the SEC effects higher than free HT. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Elevated body temperature and increased blood vessel sensitivity in spontaneously hypertensive rats.

PubMed

Price, J M; Wilmoth, F R

1990-04-01

Body temperature (BT) was significantly greater in spontaneously hypertensive rats (SHR) than in Wistar-Kyoto (WKY) rats regardless of the time of day, length of rectal probe, sex, age, or commercial vendor. Bath temperature (theta) for excised aortic rings was controlled by a thermoelectric Peltier module with an accuracy of 0.1 degree C. At peak force in individual contractions of norepinephrine (NE) dose-response experiments, theta was changed from 37 to 39 degrees C. Active and resting wall tension (Tw) were increased, and the mean effective dose (ED50) was decreased in the SHR aorta with and without endothelium. For the WKY aorta, active and resting Tw were increased, but ED50 was the same with and without endothelium. These results were supported by experiments where theta was decreased from 39 to 37 degrees C and by experiments on Sprague-Dawley rats. Potassium dose-response experiments with aorta from SHR and WKY rats show an increase in sensitivity at 39 degrees C, but active Tw is the same at 39 and 37 degrees C. When compared at the BT of each rat, the NE ED50 was lower and resting Tw was higher in the SHR aorta than in the WKY aorta, but active Tw was the same.(ABSTRACT TRUNCATED AT 250 WORDS)

A systematic review of primary endovascular repair of the ascending aorta.

PubMed

Muetterties, Corbin E; Menon, Rohan; Wheatley, Grayson H

2018-01-01

Endovascular repair of the ascending aorta is currently limited to patients at high surgical risk with aortic diseases originating above the sinotubular junction. A number of different endovascular technologies and approaches have been used, although no consensus exists regarding a standardized technique. To better understand real-world endovascular approaches to the ascending aorta, we performed a comprehensive review of the types of endovascular aortic stents and associated vascular access used in repair of the ascending aorta. A search of the MEDLINE database was conducted from January 1, 1995, through January 31, 2017, with the search term "ascending aortic stent." Studies involving endovascular stenting in which the primary therapy was confined exclusively to the ascending aorta were included. Studies involving hybrid arch procedures and surgical replacement of the ascending aorta associated with aortic stenting were excluded. The type of aortic stent, underlying aortic disease, and surgical approach were recorded along with outcomes, need for reinterventions, and follow-up. A total of 46 publications that focused on primary endovascular repair of the ascending aorta were identified. Thirteen different aortic stent grafts of various designs were used in 118 total patients. The most commonly used device types were thoracic stents (n = 84 [71.2%]) along with abdominal cuffs (n = 13 [11%]) and custom-made grafts (n = 12 [10.2%]). The most commonly treated aortic disease was type A aortic dissection (n = 59 [50%]), followed by aortic pseudoaneurysm (n = 35 [29.7%]), aortic aneurysm (n = 6 [5.1%]), penetrating atherosclerotic ulcer (n = 5 [4.2%]), and acute aortic rupture (n = 3 [2.5%]). Femoral arterial access was used in 62.7% of patients (n = 74); transapical (n = 17 [14.4%]), carotid (n = 15 [12.7%]), and axillary (n = 8 [6.8%]) approaches were also used. The overall type I endoleak rate was 18.6% (n = 22), with 11 patients (9.3%) requiring reintervention. Other complications included all-cause mortality (n = 18 [15.2%]), conversions to open surgery (n = 4 [3.4%]), and cerebrovascular complications (n = 4 [3.4%]). Aorta-related mortality was 5% (n = 6), and average follow-up was 17.2 months. Despite the absence of a dedicated aortic stent graft for the ascending aorta, patients with a range of ascending aortic diseases are being successfully treated by endovascular technologies. For optimal outcomes, patient selection is critical to align aortic anatomy with the limited device sizing options, and it should be reserved for patients at high surgical risk. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Influence of elastin-derived peptides on metalloprotease production in endothelial cells.

PubMed

Siemianowicz, Krzysztof; Gminski, Jan; Goss, Malgorzata; Francuz, Tomasz; Likus, Wirginia; Jurczak, Teresa; Garczorz, Wojciech

2010-11-01

Matrix metalloproteases (MMPs) are a family of zinc-dependent endopeptidases that degrade extracellular matrix proteins. MMP-1 and MMP-2 are produced by endothelial cells and are involved in specific vascular pathologies, including atherosclerosis and aortal aneurysm. One of the most important differences between these two metalloproteases is the possibility of hydrolysis of elastin and collagen type IV by MMP-2, but not by MMP-1. Elastin-derived peptides are generated as a result of the degradation of elastin fibers. The aim of our study was to compare the production of MMP-1 and MMP-2 in cultured human arterial endothelial cells derived from vascular pathologies localized at three different sites, the coronary artery, iliac artery and aorta, measured as their concentration in cell culture medium. The second aim was to evaluate the influence of κ-elastin (at concentrations 0.1, 0.4, 1.0, 2.5 or 5.0 μg/ml) on the production of the evaluated metalloproteases in three endothelial cell lines. The production of MMP-1 was statistically significantly greater in endothelial cells derived from the aorta compared to that in the endothelium obtained from the coronary and iliac arteries. There were no statistically significant differences in the production of MMP-2 among the endothelial cell lines tested. The addition of κ-elastin at all evaluated concentrations did not statistically significantly influence the concentration of MMP-1 in the cultured coronary artery endothelium. Furthermore, no statistically significant differences were observed in the cultured iliac artery endothelium. In the cultured endothelium derived from the aorta, κ-elastin at concentrations of 0.1 and 0.4 μg/ml significantly increased the amount of MMP-1.

Influence of elastin-derived peptides on metalloprotease production in endothelial cells

PubMed Central

SIEMIANOWICZ, KRZYSZTOF; GMINSKI, JAN; GOSS, MALGORZATA; FRANCUZ, TOMASZ; LIKUS, WIRGINIA; JURCZAK, TERESA; GARCZORZ, WOJCIECH

2010-01-01

Matrix metalloproteases (MMPs) are a family of zinc-dependent endopeptidases that degrade extracellular matrix proteins. MMP-1 and MMP-2 are produced by endothelial cells and are involved in specific vascular pathologies, including atherosclerosis and aortal aneurysm. One of the most important differences between these two metalloproteases is the possibility of hydrolysis of elastin and collagen type IV by MMP-2, but not by MMP-1. Elastin-derived peptides are generated as a result of the degradation of elastin fibers. The aim of our study was to compare the production of MMP-1 and MMP-2 in cultured human arterial endothelial cells derived from vascular pathologies localized at three different sites, the coronary artery, iliac artery and aorta, measured as their concentration in cell culture medium. The second aim was to evaluate the influence of κ-elastin (at concentrations 0.1, 0.4, 1.0, 2.5 or 5.0 μg/ml) on the production of the evaluated metalloproteases in three endothelial cell lines. The production of MMP-1 was statistically significantly greater in endothelial cells derived from the aorta compared to that in the endothelium obtained from the coronary and iliac arteries. There were no statistically significant differences in the production of MMP-2 among the endothelial cell lines tested. The addition of κ-elastin at all evaluated concentrations did not statistically significantly influence the concentration of MMP-1 in the cultured coronary artery endothelium. Furthermore, no statistically significant differences were observed in the cultured iliac artery endothelium. In the cultured endothelium derived from the aorta, κ-elastin at concentrations of 0.1 and 0.4 μg/ml significantly increased the amount of MMP-1. PMID:22993640

mTOR (Mechanistic Target of Rapamycin) Inhibition Decreases Mechanosignaling, Collagen Accumulation, and Stiffening of the Thoracic Aorta in Elastin-Deficient Mice.

PubMed

Jiao, Yang; Li, Guangxin; Li, Qingle; Ali, Rahmat; Qin, Lingfeng; Li, Wei; Qyang, Yibing; Greif, Daniel M; Geirsson, Arnar; Humphrey, Jay D; Tellides, George

2017-09-01

Elastin deficiency because of heterozygous loss of an ELN allele in Williams syndrome causes obstructive aortopathy characterized by medial thickening and fibrosis and consequent aortic stiffening. Previous work in Eln -null mice with a severe arterial phenotype showed that inhibition of mTOR (mechanistic target of rapamycin), a key regulator of cell growth, lessened the aortic obstruction but did not prevent early postnatal death. We investigated the effects of mTOR inhibition in Eln -null mice partially rescued by human ELN that manifest a less severe arterial phenotype and survive long term. Thoracic aortas of neonatal and juvenile mice with graded elastin deficiency exhibited increased signaling through both mTOR complex 1 and 2. Despite lower predicted wall stress, there was increased phosphorylation of focal adhesion kinase, suggestive of greater integrin activation, and increased transforming growth factor-β-signaling mediators, associated with increased collagen expression. Pharmacological blockade of mTOR by rapalogs did not improve luminal stenosis but reduced mechanosignaling (in delayed fashion after mTOR complex 1 inhibition), medial collagen accumulation, and stiffening of the aorta. Rapalog administration also retarded somatic growth, however, and precipitated neonatal deaths. Complementary, less-toxic strategies to inhibit mTOR via altered growth factor and nutrient responses were not effective. In addition to previously demonstrated therapeutic benefits of rapalogs decreasing smooth muscle cell proliferation in the absence of elastin, we find that rapalogs also prevent aortic fibrosis and stiffening attributable to partial elastin deficiency. Our findings suggest that mTOR-sensitive perturbation of smooth muscle cell mechanosensing contributes to elastin aortopathy. © 2017 American Heart Association, Inc.

Pathogenesis of solitary right aortic arch: a mass effect hypothesis based on observations of serial human embryonic sections.

PubMed

Jin, Zhe W; Yamada, Tomonori; Kim, Ji H; Rodríguez-Vázquez, José F; Murakami, Gen; Arakawa, Keiji

2017-03-01

In general, solitary right aortic arch carries the left-sided ductus arteriosus communicating between the left subclavian and pulmonary arteries or the right-sided ductus connecting the descending aorta to the left pulmonary artery. Serial sections of fifteen 5- to 6-week-old embryos and ten 8- to 9-week-old fetuses suggested that the pathogenesis was unrelated to inversion due to dysfunction in gene cascades that control the systemic left/right axis. With inversion, conversely, the ductus or the sixth pharyngeal arch artery should connect to the right pulmonary artery. The disappearance of the right aortic arch started before the caudal migration of the aortic attachment of the ductus. Sympathetic nerve ganglia developed immediately posterior to both aortae, with a single embryonic specimen showing a large ganglion at the midline close to the union of the aortic arches. These ganglia may interfere with blood flow through the distal left arch, resulting in the ductus ending at the descending aorta behind the oesophagus. In another fetus examined, a midline shift of the ductus course resulted in the trachea curving posteriorly. Therefore, solitary right arch is likely to accompany abnormalities of the surrounding structures. The timing and site of the obstruction should be different between types: an almost midline obstruction near the aortic union needed for the development of the left-sided ductus and a distal obstruction near the left subclavian arterial origin needed for the development of the right-sided ductus. A mass effect of the sympathetic ganglia may explain the pathogenesis of any type of anomalous ductus arteriosus shown in previous reports of the solitary right arch.

Inhibition of endoplasmic reticulum stress by intermedin1-53 attenuates angiotensin II-induced abdominal aortic aneurysm in ApoE KO Mice.

PubMed

Ni, Xian-Qiang; Lu, Wei-Wei; Zhang, Jin-Sheng; Zhu, Qing; Ren, Jin-Ling; Yu, Yan-Rong; Liu, Xiu-Ying; Wang, Xiu-Jie; Han, Mei; Jing, Qing; Du, Jie; Tang, Chao-Shu; Qi, Yong-Fen

2018-06-26

Endoplasmic reticulum stress (ERS) is involved in the development of abdominal aortic aneurysm (AAA). Since bioactive peptide intermedin (IMD)1-53 protects against AAA formation, here we investigated whether IMD1-53 attenuates AAA by inhibiting ERS. AAA model was induced by angiotensin II (AngII) in ApoE KO mouse background. AngII-treated mouse aortas showed increased ERS gene transcription of caspase12, eukaryotic translation initiation factor 2a (eIf2a) and activating transcription factor 4(ATF4).The protein level of ERS marker glucose regulated protein 94(GRP94), ATF4 and C/EBP homologous protein 10(CHOP) was also up-regulated by AngII. Increased ERS levels were accompanied by severe VSMC apoptosis in human AAA aorta. In vivo administration of IMD1-53 greatly reduced AngII-induced AAA and abrogated the activation of ERS. To determine whether IMD inhibited AAA by ameliorating ERS, we used 2 non-selective ERS inhibitors phenyl butyrate (4-PBA) and taurine (TAU). Similar to IMD, PBA, and TAU significantly reduced the incidence of AAA and AAA-related pathological disorders. In vitro, AngII infusion up-regulated CHOP, caspase12 expression and led to VSMC apoptosis. IMD siRNA aggravated the CHOP, caspase12-mediated VSMC apoptosis, which was abolished by ATF4 silencing. IMD infusion promoted the phosphorylation of adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) in aortas in ApoE KO mice, and the AMPK inhibitor compound C abolished the protective effect of IMD on VSMC ERS and apoptosis induced by AngII. In conclusion, IMD may protect against AAA formation by inhibiting ERS via activating AMPK phosphorylation.

Performance assessment of Pulse Wave Imaging using conventional ultrasound in canine aortas ex vivo and normal human arteries in vivo

PubMed Central

Li, Ronny X.; Qaqish, William; Konofagou, Elisa. E.

2015-01-01

The propagation behavior of the arterial pulse wave may provide valuable diagnostic information for cardiovascular pathology. Pulse Wave Imaging (PWI) is a noninvasive, ultrasound imaging-based technique capable of mapping multiple wall motion waveforms along a short arterial segment over a single cardiac cycle, allowing for the regional pulse wave velocity (PWV) and propagation uniformity to be evaluated. The purpose of this study was to improve the clinical utility of PWI using a conventional ultrasound system. The tradeoff between PWI spatial and temporal resolution was evaluated using an ex vivo canine aorta (n = 2) setup to assess the effects of varying image acquisition and signal processing parameters on the measurement of the PWV and the pulse wave propagation uniformity r2. PWI was also performed on the carotid arteries and abdominal aortas of 10 healthy volunteers (24.8 ± 3.3 y.o.) to determine the waveform tracking feature that would yield the most precise PWV measurements and highest r2 values in vivo. The ex vivo results indicated that the highest precision for measuring PWVs ~ 2.5 – 3.5 m/s was achieved using 24–48 scan lines within a 38 mm image plane width (i.e. 0.63 – 1.26 lines/mm). The in vivo results indicated that tracking the 50% upstroke of the waveform would consistently yield the most precise PWV measurements and minimize the error in the propagation uniformity measurement. Such findings may help establish the optimal image acquisition and signal processing parameters that may improve the reliability of PWI as a clinical measurement tool. PMID:26640603

Detection of Sequence-Specific Tyrosine Nitration of Manganese SOD and SERCA in Cardiovascular Disease and Aging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Shanqin; Ying, Jia; Jiang, Bingbing

2006-06-01

Nitration of protein tyrosine residues (nY) is a marker of oxidative stress and may alter the biological activity of the modified proteins. The aim of this study was to develop antibodies towards site-specific nY-modified proteins and to use histochemical and immunoblotting to demonstrate protein nitration in tissues. Affinity-purified polyclonal antibodies towards peptides with known nY sites in MnSOD nY-34 and of two adjacent nY in the sarcoplasmic endoplasmic reticulum calcium ATPase (SERCA2 di-nY-294,295) were developed. Kidneys from rats infused with angiotensin II with known MnSOD nY and aorta from atherosclerotic rabbits and aging rat skeletal and cardiac sarcoplasmic reticulum withmore » known SERCA di-nY were used for positive controls. Staining for MnSOD nY-34 was most intense in distal renal tubules and collecting ducts. Staining of atherosclerotic aorta for SERCA2 di-nY was most intense in atherosclerotic plaques. Aging rat skeletal muscle and atherosclerotic aorta and cardiac atrium from human diabetic patients also stained positively. Staining was decreased by sodium dithionite that chemically reduces nitrotyrosine to aminotyrosine, and the antigenic nY-peptide blocked staining for each respective nY site, but not for the other. As previously demonstrated, immunoblotting failed to detect these modified proteins in whole tissue lysates, but did when the proteins were concentrated. Immunohistochemical staining for specific nY-modified tyrosine residues offers the ability to assess the effects of oxidant stress associated with pathological conditions on individual proteins whose function may be affected in specific tissue sites.« less

Roles of affinity and lipophilicity in the slow kinetics of prostanoid receptor antagonists on isolated smooth muscle preparations

PubMed Central

Jones, RL; Woodward, DF; Wang, JW; Clark, RL

2011-01-01

BACKGROUND AND PURPOSE The highly lipophilic acyl-sulphonamides L-798106 and L-826266 showed surprisingly slow antagonism of the prostanoid EP3 receptor system in guinea-pig aorta. Roles of affinity and lipophilicity in the onset kinetics of these and other prostanoid ligands were investigated. EXPERIMENTAL APPROACH Antagonist selectivity was assessed using a panel of human recombinant prostanoid receptor-fluorimetric imaging plate reader assays. Potencies/affinities and onset half-times of agonists and antagonists were obtained on guinea-pig-isolated aorta and vas deferens. n-Octanol-water partition coefficients were predicted. KEY RESULTS L-798106, L-826266 and the less lipophilic congener (DG)-3ap appear to behave as selective, competitive-reversible EP3 antagonists. For ligands of low to moderate lipophilicity, potency increments for EP3 and TP (thromboxane-like) agonism on guinea-pig aorta (above pEC50 of 8.0) were associated with progressively longer onset half-times; similar trends were found for TP and histamine H1 antagonism above a pA2 limit of 8.0. In contrast, L-798106 (EP3), L-826266 (EP3, TP) and the lipophilic H1 antagonists astemizole and terfenadine exhibited very slow onset rates despite their moderate affinities; (DG)-3ap (EP3) had a faster onset. Agonism and antagonism on the vas deferens EP3 system were overall much faster, although trends were similar. CONCLUSIONS AND IMPLICATIONS High affinity and high liphophilicity may contribute to the slow onsets of prostanoid ligands in some isolated smooth muscle preparations. Both relationships are explicable by tissue disposition under the limited diffusion model. EP3 antagonists used as research tools should have moderate lipophilicity. The influence of lipophilicity on the potential clinical use of EP3 antagonists is discussed. PMID:20973775

[Effect of external abdominal aorta compression on circulation during anesthesia induction in elderly patients].

PubMed

Li, Xiuman; Wang, Lixiang

2017-07-01

To investigate the effect of external abdominal aorta compression on circulation during anesthetic induction in elderly patients. A prospective randomized controlled trial was conducted. Patients with age of 60-75 years old, requiring a general anesthesia for non-abdominal surgery, and with II-III class of American Society of Anesthesiologists (ASA) physical status classification, and admitted to General Hospital of Chinese People's Armed Police Forces from January to April in 2017 were enrolled. They were divided into abdominal aorta pressure group and control group according to random number method, with 20 patients in each group. In both groups, anesthesia was induced with midazolam, propofol, fentanyl and cisatracurium, and was maintained with propofol, remifentanil and cisatracurium. After successful intubation, the anesthesia machine was changed into mechanical ventilation. The patients in abdominal aorta pressure group were given abdominal aorta pressure 1 minute after induction of general anesthesia with midazolam till 5 minutes after intubation. The mean arterial pressure (MAP), heart rate (HR) and blood oxygen saturation (SpO 2 ) were observed before anesthesia induction, immediately after anesthesia induction, immediately after intubation, 5 minutes and 10 minutes after intubation, respectively. The incidence of hypotension or bradycardia, and usage of ephedrine or atropine were recorded. There were no significant differences in MAP [mmHg (1 mmHg = 0.133 kPa): 83.6±4.7 vs. 82.9±4.7], HR (bpm: 67.3±5.9 vs. 65.9±5.7) and SpO 2 (0.962±0.007 vs. 0.960±0.009) before anesthesia induction between abdominal aorta pressure group and control group (all P > 0.05). Immediately after anesthesia induction, the MAP and HR in control group were significantly decreased as compared with those before anesthesia induction [MAP (mmHg): 70.0±8.7 vs. 82.9±4.7, HR (bpm): 60.7±6.7 vs. 65.9±5.7, both P < 0.05], and they were also significantly lower than those of abdominal aorta pressure group [MAP (mmHg): 83.1±3.9, HR (bpm): 66.8±4.9, both P < 0.05]. Immediately after intubation, the MAP and HR in control group were significantly increased as compared with those immediately after anesthesia induction [MAP (mmHg): 78.9±7.9 vs. 70.0±8.7, HR (bpm): 67.3±2.7 vs. 60.7±6.7, both P < 0.05], but the changes in MAP and HR in abdominal aorta pressure group were not obvious. During the anesthesia induction period, there was no statistical difference in SpO 2 change between the two groups. During induction of anesthesia, no adverse reaction was found in the abdominal aorta pressure group, but 4 patients with hypotension and 2 patients with bradycardia were found in the control group. Two patients with hypotension were treated with ephedrine, and 2 patients with bradycardia were treated with atropine. Anesthesia induction of elderly patients with abdominal aorta pressure can help maintain hemodynamic stability.

Inhibitive Effects of Quercetin on Myeloperoxidase-Dependent Hypochlorous Acid Formation and Vascular Endothelial Injury.

PubMed

Lu, Naihao; Sui, Yinhua; Tian, Rong; Peng, Yi-Yuan

2018-05-16

Myeloperoxidase (MPO) from activated neutrophils plays important roles in multiple human inflammatory diseases by catalyzing the formation of powerful oxidant hypochlorous acid (HOCl). As a major flavonoid in the human diet, quercetin has been suggested to act as antioxidant and anti-inflammatory agent in vitro and in vivo. In this study, we showed that quercetin inhibited MPO-mediated HOCl formation (75.0 ± 6.2% for 10 μM quercetin versus 100 ± 5.2% for control group, P < 0.01) and cytotoxicity to endothelial cells in vitro, while this flavonoid was nontoxic to endothelial cell cultures ( P > 0.05, all cases). Moreover, quercetin inhibited HOCl generation by stimulated neutrophils (a rich source of MPO) and protected endothelial cells from neutrophils-induced injury. Furthermore, quercetin could inhibit HOCl-induced endothelial dysfunction such as loss of cell viability, and decrease of nitric oxide formation in endothelial cells ( P < 0.05, all cases). Consistent with these in vitro data, quercetin attenuated lipopolysaccharide-induced endothelial dysfunction and increase of MPO activity in mouse aortas, while this flavonoid could protect against HOCl-mediated endothelial dysfunction in isolated aortas ( P < 0.05). Therefore, it was proposed that quercetin attenuated endothelial injury in inflammatory vasculature via inhibition of vascular-bound MPO-mediated HOCl formation or scavenging of HOCl. These data indicate that quercetin is a nontoxic inhibitor of MPO activity and MPO/neutrophils-induced cytotoxicity in endothelial cells and may be useful for targeting MPO-dependent vascular disease and inflammation.

Quantification of wall shear stress in large blood vessels using Lagrangian interpolation functions with cine phase-contrast magnetic resonance imaging.

PubMed

Cheng, Christopher P; Parker, David; Taylor, Charles A

2002-09-01

Arterial wall shear stress is hypothesized to be an important factor in the localization of atherosclerosis. Current methods to compute wall shear stress from magnetic resonance imaging (MRI) data do not account for flow profiles characteristic of pulsatile flow in noncircular vessel lumens. We describe a method to quantify wall shear stress in large blood vessels by differentiating velocity interpolation functions defined using cine phase-contrast MRI data on a band of elements in the neighborhood of the vessel wall. Validation was performed with software phantoms and an in vitro flow phantom. At an image resolution corresponding to in vivo imaging data of the human abdominal aorta, time-averaged, spatially averaged wall shear stress for steady and pulsatile flow were determined to be within 16% and 23% of the analytic solution, respectively. These errors were reduced to 5% and 8% with doubling in image resolution. For the pulsatile software phantom, the oscillation in shear stress was predicted to within 5%. The mean absolute error of circumferentially resolved shear stress for the nonaxisymmetric phantom decreased from 28% to 15% with a doubling in image resolution. The irregularly shaped phantom and in vitro investigation demonstrated convergence of the calculated values with increased image resolution. We quantified the shear stress at the supraceliac and infrarenal regions of a human abdominal aorta to be 3.4 and 2.3 dyn/cm2, respectively.

Uncovering Topological Structures in Unstructured Data

DTIC Science & Technology

2015-04-20

paper [4] presents an approach for constructing statistical shape models (SSMs) for aortic surfaces with the eventual goal of mapping the mean aorta ...characterize the variation pattern are found after optimizing the group-wise correspondence across the aorta training set. We use the direct

77 FR 66847 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-07

... cardiac cycle. During diastole, the balloon will inflate, creating a rise in pressure in the aorta, thus..., deflation of the balloon causes a fall in pressure in the aorta, which assists the left ventricle by...

Endovascular treatment of symptomatic true-lumen collapse of the downstream aorta after open surgery for acute aortic dissection type A.

PubMed

Conzelmann, L O; Doemland, M; Weigang, E; Frieß, T; Schotten, S; Düber, C; Vahl, C F

2013-04-01

The aim of the present study was to evaluate the outcome of endovascular treatment of true-lumen collapse (TLC) of the downstream aorta after open surgery for acute aortic dissection type A (AADA). Retrospective, observational study with follow-up of 16 ± 7.6 months. From April 2010 to January 2012, 89 AADA-patients underwent aortic surgery. Out of these, computed tomography revealed a TLC of the downstream aorta in 13 patients (14.6%). They all received additional thoracic endovascular aortic repair (TEVAR) in consequence of malperfusion syndromes. In all 13 TLC-patients, dissection after AADA-surgery extended from the aortic arch to the abdominal aorta and malperfusion syndromes occurred. Remodeling of the true-lumen was achieved by TEVAR with complemental stent disposal in abdominal and iliac arteries in all cases. One patient died on the third postoperative day due to intracerebral hemorrhage. Another patient, who presented under severe cardiogenic shock died despite AADA-surgery and TEVAR-treatment. Thirty-day mortality was 15.4% in TLC-patients (N = 2/13). In the follow-up period, 3 patients required additional aortic stents after the emergency TEVAR procedures. After 20 weeks, a third patient died secondary to malperfusion due to false-lumen recanalization. Therefore, late mortality was 23.1%. After proximal aortic repair for AADA, early postoperative computed tomography should be demanded in all patients to exclude a TLC of the descending aorta. Mortality is still substantial in these patients despite instant TEVAR application. Thus, in case of TLC and malperfusion syndrome of the downstream aorta, TEVAR should be performed early to alleviate or even prevent ischemic injury.

Concomitant replacement of the dilated ascending aorta during aortic valve replacement; does it increase the perioperative morbidity and mortality risks?

PubMed

Lim, Ju Y; Jung, Sung H; Kim, Joon B; Kim, Dong K; Chung, Cheol H; Song, Hyun; Lee, Jae W; Choo, Suk J

2013-05-01

Concerns of increased surgical risks with ascending aortic replacement have led surgeons to manage post-stenotic aortic dilatation more conservatively during aortic valve replacement (AVR). The present study aimed to assess the prognostic implications and surgical risks of replacing the dilated aorta during AVR. Between January 1999 and March 2010, 134 patients who received surgery for aortic stenosis and post-stenotic dilatation (aorta size ≥40 mm) were included in the present study. AVR was performed in 92 patients (AVR group) while aortic valve and ascending aorta replacement (AVR + aorta group) were performed in 42 patients. Overall survival was compared between the two groups using Cox proportional hazard model after adjustment with inverse-probability-of-treatment weighting. The mean follow-up duration was 3.5 ± 3 years. There were no significant differences in the operative mortality and morbidity between the two groups. The late cardiac deaths were also not significantly different between the two groups (p = 1.00). In the AVR group, the ascending aortic expansion rate which was 0.18 mm/year over a mean follow-up duration of 2.3 ± 2.2 years by echocardiography showed a positive correlation with time (r = 0.3, p = 0.08). A relatively greater aortic expansion rate was identified as a risk factor for late mortality (p = 0.015, HR 1.08 (CI: 1.02 to 1.15). Concomitant replacement of the dilated ascending aorta during AVR did not increase the immediate postoperative morbidity or mortality risks and tended to exert a long-term beneficial effect on the risk of late mortality. © 2013 Wiley Periodicals, Inc.

Initial medical management in acute type A aortic dissection patients with a thrombosed false lumen in the ascending aorta combining intramural hematoma and retrograde dissection from the descending to the ascending aorta.

PubMed

Sadamatsu, Kenji; Takase, Susumu; Sagara, Shuichiro; Ohe, Kensuke; Nishi, Jun-Ichiro; Tashiro, Hideki; Kosuga, Tomokazu; Yasunaga, Hiroshi

2018-05-01

The feasibility of medical management for select patients with acute type A aortic dissection has been reported from a few institutions. In this study, we retrospectively investigated the safety and feasibility of our conservative approach for patients with type A aortic dissection in daily practice. From January 2013 to December 2017, 131 consecutive patients were admitted to our institution for acute aortic dissection, including 58 patients of type A. Initial medical management was attempted in select patients who were clinically stable and had a thrombosed false lumen of the ascending aorta without ulcer-like projections in the ascending aorta. Except for nine patients contraindicated for surgery, urgent surgery was performed in 26 patients (SRG group), while 23 patients (MED group) were treated with the initial medical management. The maximum diameter of the ascending aorta was significantly larger in the SRG group than in the MED group. In the MED group, the heart rate and blood pressures were well-controlled at admission to the intensive-care unit, and the systolic blood pressure was further reduced at 24 h after. The in-hospital mortality rates of the MED and SRG groups were 0% and 15%, respectively. During the follow-up period, the survival rate was significantly higher in the MED group than in the SRG group, and the aortic event-free survival at one year was 80%. The initial medical management for select patients with a thrombosed false lumen in the ascending aorta was a safe and feasible strategy in real-world practice.

Comparison between multi-shot gradient echo EPI and balanced SSFP in unenhanced 3T MRA of thoracic aorta in healthy volunteers.

PubMed

Iyama, Yuji; Nakaura, Takeshi; Nagayama, Yasunori; Oda, Seitaro; Utsunomiya, Daisuke; Kidoh, Masafumi; Yuki, Hideaki; Hirata, Kenichiro; Namimoto, Tomohiro; Kitajima, Mika; Morita, Kosuke; Funama, Yoshinori; Takemura, Atsushi; Tokuyasu, Shinichi; Okuaki, Tomoyuki; Yamashita, Yasuyuki

2017-11-01

The purpose of this study was to compare scan time and image quality between magnetic resonance angiography (MRA) of the thoracic aorta using a multi-shot gradient echo planar imaging (MSG-EPI) and MRA using balanced steady-state free precession (b-SSFP). Healthy volunteers (n=17) underwent unenhanced thoracic aorta MRA using balanced steady-state free precession (b-SSFP) and MSG-EPI sequences on a 3T MRI. The acquisition time, total scan time, signal-to-noise ratio (SNR) of the thoracic aorta, and the coefficient of variation (CV) of thoracic aorta were compared with paired t-tests. Two radiologists independently recorded the images' contrast, noise, sharpness, artifacts, and overall quality on a 4-point scale. The acquisition time was 36.2% shorter for MSG-EPI than b-SSFP (115.5±14.4 vs 181.0±14.9s, p<0.01). The total scan time was 40.4% shorter for MSG-EPI than b-SSFP (272±78 vs 456±144s, p<0.01). There was no significant difference in mean SNR between MSG-EPI and b-SSFP scans (17.3±3.6 vs 15.2±4.3, p=0.08). The CV was significantly lower for MSG-EPI than b-SSFP (0.2±0.1 vs. 0.5±0.2, p<0.01). All qualitative scores except for image noise were significantly higher in MSG-EPI than b-SSFP scans (p<0.05). The MSG-EPI sequence is a promising technique for shortening scan time and yielding more homogenous image quality in MRA of thoracic aorta on 3T scanners compared with the b-SSFP. Copyright © 2017 Elsevier B.V. All rights reserved.

Accuracy of Inferior Vena Cava Ultrasound for Predicting Dehydration in Children with Acute Diarrhea in Resource-Limited Settings.

PubMed

Modi, Payal; Glavis-Bloom, Justin; Nasrin, Sabiha; Guy, Allysia; Chowa, Erika P; Dvor, Nathan; Dworkis, Daniel A; Oh, Michael; Silvestri, David M; Strasberg, Stephen; Rege, Soham; Noble, Vicki E; Alam, Nur H; Levine, Adam C

2016-01-01

Although dehydration from diarrhea is a leading cause of morbidity and mortality in children under five, existing methods of assessing dehydration status in children have limited accuracy. To assess the accuracy of point-of-care ultrasound measurement of the aorta-to-IVC ratio as a predictor of dehydration in children. A prospective cohort study of children under five years with acute diarrhea was conducted in the rehydration unit of the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b). Ultrasound measurements of aorta-to-IVC ratio and dehydrated weight were obtained on patient arrival. Percent weight change was monitored during rehydration to classify children as having "some dehydration" with weight change 3-9% or "severe dehydration" with weight change > 9%. Logistic regression analysis and Receiver-Operator Characteristic (ROC) curves were used to evaluate the accuracy of aorta-to-IVC ratio as a predictor of dehydration severity. 850 children were enrolled, of which 771 were included in the final analysis. Aorta to IVC ratio was a significant predictor of the percent dehydration in children with acute diarrhea, with each 1-point increase in the aorta to IVC ratio predicting a 1.1% increase in the percent dehydration of the child. However, the area under the ROC curve (0.60), sensitivity (67%), and specificity (49%), for predicting severe dehydration were all poor. Point-of-care ultrasound of the aorta-to-IVC ratio was statistically associated with volume status, but was not accurate enough to be used as an independent screening tool for dehydration in children under five years presenting with acute diarrhea in a resource-limited setting.

Accuracy of Inferior Vena Cava Ultrasound for Predicting Dehydration in Children with Acute Diarrhea in Resource-Limited Settings

PubMed Central

Modi, Payal; Glavis-Bloom, Justin; Nasrin, Sabiha; Guy, Allysia; Rege, Soham; Noble, Vicki E.; Alam, Nur H.; Levine, Adam C.

2016-01-01

Introduction Although dehydration from diarrhea is a leading cause of morbidity and mortality in children under five, existing methods of assessing dehydration status in children have limited accuracy. Objective To assess the accuracy of point-of-care ultrasound measurement of the aorta-to-IVC ratio as a predictor of dehydration in children. Methods A prospective cohort study of children under five years with acute diarrhea was conducted in the rehydration unit of the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b). Ultrasound measurements of aorta-to-IVC ratio and dehydrated weight were obtained on patient arrival. Percent weight change was monitored during rehydration to classify children as having “some dehydration” with weight change 3–9% or “severe dehydration” with weight change > 9%. Logistic regression analysis and Receiver-Operator Characteristic (ROC) curves were used to evaluate the accuracy of aorta-to-IVC ratio as a predictor of dehydration severity. Results 850 children were enrolled, of which 771 were included in the final analysis. Aorta to IVC ratio was a significant predictor of the percent dehydration in children with acute diarrhea, with each 1-point increase in the aorta to IVC ratio predicting a 1.1% increase in the percent dehydration of the child. However, the area under the ROC curve (0.60), sensitivity (67%), and specificity (49%), for predicting severe dehydration were all poor. Conclusions Point-of-care ultrasound of the aorta-to-IVC ratio was statistically associated with volume status, but was not accurate enough to be used as an independent screening tool for dehydration in children under five years presenting with acute diarrhea in a resource-limited setting. PMID:26766306

Elephant trunk in a small-calibre true lumen for chronic aortic dissection: cause of haemolytic anaemia?

PubMed

Araki, Haruna; Kitamura, Tadashi; Horai, Tetsuya; Shibata, Ko; Miyaji, Kagami

2014-12-01

The elephant trunk technique for aortic dissection is useful for reducing false lumen pressure; however, a folded vascular prosthesis inside the aorta can cause haemolysis. The purpose of this study was to investigate whether an elephant trunk in a small-calibre lumen can cause haemolysis. Inpatient and outpatient records were retrospectively reviewed. Two cases of haemolytic anaemia after aortic surgery using the elephant trunk technique were identified from 2011 to 2013. A 64-year-old man, who underwent graft replacement of the ascending aorta for acute Stanford type A aortic dissection, presented with enlargement of the chronic dissection of the descending aorta and moderate aortic regurgitation. A two-stage surgery was scheduled. Total arch replacement with an elephant trunk in the true lumen and concomitant aortic valve replacement were performed. Postoperatively, he developed severe haemolytic anaemia because of the folded elephant trunk. The anaemia improved after the second surgery, including graft replacement of the descending aorta. Similarly, a 61-year-old man, who underwent total arch replacement for acute Stanford type A aortic dissection, presented with enlargement of the chronic dissection of the descending aorta. Graft replacement of the descending aorta with an elephant trunk inserted into the true lumen was performed. The patient postoperatively developed haemolytic anaemia because of the folded elephant trunk, which improved after additional stent grafting into the elephant trunk. A folded elephant trunk in a small-calibre lumen can cause haemolysis. Therefore, inserting an elephant trunk in a small-calibre true lumen during surgery for chronic aortic dissection should be avoided. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Proteome profiling in the aorta and kidney of type 1 diabetic rats

PubMed Central

Zhu, Rui; Jaffa, Miran A.; Zhao, Jingfu; Mirzaei, Parvin; Ahmed, Adnan; Kobeissy, Firas; Ziyadeh, Fuad N.; Mechref, Yehia

2017-01-01

Diabetes is associated with a number of metabolic and cardiovascular risk factors that contribute to a high rate of microvascular and macrovascular complications. The risk factors and mechanisms that contribute to the development of micro- and macrovascular disease in diabetes are not fully explained. In this study, we employed mass spectrometric analysis using tandem LC-MS/MS to generate a proteomic profile of protein abundance and post-translational modifications (PTM) in the aorta and kidney of diabetic rats. In addition, systems biology analyses were employed to identify key protein markers that can provide insights into molecular pathways and processes that are differentially regulated in the aorta and kidney of type 1 diabetic rats. Our results indicated that 188 (111 downregulated and 77 upregulated) proteins were significantly identified in the aorta of diabetic rats compared to normal controls. A total of 223 (109 downregulated and 114 upregulated) proteins were significantly identified in the kidney of diabetic rats compared to normal controls. When the protein profiles from the kidney and aorta of diabetic and control rats were analyzed by principal component analysis, a distinct separation of the groups was observed. In addition, diabetes resulted in a significant increase in PTM (oxidation, phosphorylation, and acetylation) of proteins in the kidney and aorta and this effect was partially reversed by insulin treatment. Ingenuity pathway analysis performed on the list of differentially expressed proteins depicted mitochondrial dysfunction, oxidative phosphorylation and acute phase response signaling to be among the altered canonical pathways by diabetes in both tissues. The findings of the present study provide a global proteomics view of markers that highlight the mechanisms and putative processes that modulate renal and vascular injury in diabetes. PMID:29121074

Chronic periaortitis with thoracic aorta and epiaortic artery involvement: a systemic large vessel vasculitis?

PubMed

Palmisano, Alessandra; Urban, Maria L; Corradi, Domenico; Cobelli, Rocco; Alberici, Federico; Maritati, Federica; Versari, Annibale; Pipitone, Nicolò; Salvarani, Carlo; Buzio, Carlo; Vaglio, Augusto

2015-11-01

Chronic periaortitis (CP) is a rare disease characterized by fibro-inflammatory tissue surrounding the abdominal aorta and the iliac arteries. Anecdotal reports have shown that CP may also involve other vascular districts, particularly the thoracic aorta. The aim of this study was to investigate the thoracic aorta and epiaortic artery involvement in CP. Patients were eligible if they had undergone imaging studies assessing inflammatory involvement of the thoracic aorta and its major branches (e.g. contrast CT, MRI or PET-CT). We explored the patterns of thoracic vessel involvement and compared the clinical characteristics of patients with and without thoracic disease. Where available, we also reviewed the thoracic vascular/perivascular tissue biopsies. Of 153 CP patients seen between 1999 and 2012, 77 were eligible. Of these, 28 (36%) had thoracic involvement: 15 (54%) had thoracic periaortitis, with 7 also showing epiaortic artery involvement; 6 (21%) had periaortitis surrounding a thoracic aortic aneurysm, 2 of them with epiaortic artery involvement; 7 (25%) had a thoracic aortic aneurysm without periaortitis. Patients with thoracic disease were more frequently female (P = 0.01), were older (P = 0.001) and had a higher frequency of pain and constitutional symptoms (P = 0.02). Thoracic (peri)vascular biopsies revealed adventitial and peri-adventitial fibro-inflammatory patterns similar to those observed in abdominal CP. In about one-third of patients, CP also involves the thoracic aorta and the epiaortic arteries, which supports the hypothesis of a systemic inflammatory disease of the large arteries. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Biomechanical properties of the Marfan's aortic root and ascending aorta before and after personalised external aortic root support surgery.

PubMed

Singh, S D; Xu, X Y; Pepper, J R; Treasure, T; Mohiaddin, R H

2015-08-01

Marfan syndrome is an inherited systemic connective tissue disease which may lead to aortic root disease causing dilatation, dissection and rupture of the aorta. The standard treatment is a major operation involving either an artificial valve and aorta or a complex valve repair. More recently, a personalised external aortic root support (PEARS) has been used to strengthen the aorta at an earlier stage of the disease avoiding risk of both rupture and major surgery. The aim of this study was to compare the stress and strain fields of the Marfan aortic root and ascending aorta before and after insertion of PEARS in order to understand its biomechanical implications. Finite element (FE) models were developed using patient-specific aortic geometries reconstructed from pre and post-PEARS magnetic resonance images in three Marfan patients. For the post-PEARS model, two scenarios were investigated-a bilayer model where PEARS and the aortic wall were treated as separate layers, and a single-layer model where PEARS was incorporated into the aortic wall. The wall and PEARS materials were assumed to be isotropic, incompressible and linearly elastic. A static load on the inner wall corresponding to the patients' pulse pressure was applied. Results from our FE models with patient-specific geometries show that peak aortic stresses and displacements before PEARS were located at the sinuses of Valsalva but following PEARS surgery, these peak values were shifted to the aortic arch, particularly at the interface between the supported and unsupported aorta. Further studies are required to assess the statistical significance of these findings and how PEARS compares with the standard treatment. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

Absence of Activation-induced Cytidine Deaminase, a Regulator of Class Switch Recombination and Hypermutation in B Cells, Suppresses Aorta Allograft Vasculopathy in Mice.

PubMed

Nakanishi, Tomonori; Xu, Xiaoyan; Wynn, Carmen; Yamada, Toshiko; Pan, Fan; Erickson, Laurie; Teo, Haeman; Nakagawa, Terry; Masunaga, Taro; Abe, Jumpei; Akamatsu, Masahiko; Tamura, Kouichi; Jiang, Hongsi

2015-08-01

Antibody-mediated rejection is caused in part by increasing circulation/production of donor-specific antibody (DSA). Activation-induced cytidine deaminase (AID) is a key regulator of class switch recombination and somatic hypermutation of immunoglobulin in B cells, yet its role in antibody-mediated transplant rejection remains unclear. We show here that AID deficiency in mice enables suppression of allograft vasculopathy (AV) after aorta transplantation, a DSA-mediated process. Splenocytes from C57BL/6 J (B6) AID(−/−) mice were used for determining in vitro proliferation responses, alloreactivity, cell surface marker expression, and antibody production. BALB/c mouse aortas were transplanted into B6 AID(−/−) mice with or without FK506 treatment. Blood and aorta grafts were harvested on day 30 after transplantation and were subjected to DSA, histological, and immunohistological analyses. The AID(−/−) splenocytes were comparable to wild type splenocytes in proliferation responses, alloreactivity, and expression of cell surface markers in vitro. However, they completely failed to produce immunoglobulin G, although they were not impaired in immunoglobulin M production relative to controls. Furthermore, BALB/c aorta grafts from B6 AID(−/−) recipient mice on day 30 after transplantation showed reduced signs of AV compared to the grafts from B6 wild type recipient mice which had severe vascular intimal hyperplasia, interstitial fibrosis, and inflammation. Treatment with FK506 produced a synergistic effect in the grafts from AID(−/−) recipients with further reduction of intimal hyperplasia and fibrosis scores. The AID deficiency inhibits DSA-mediated AV after aorta transplantation in mice. We propose that AID could be a novel molecular target for controlling antibody-mediated rejection in organ transplantation.

Proteome profiling in the aorta and kidney of type 1 diabetic rats.

PubMed

Al Hariri, Moustafa; Elmedawar, Mohamad; Zhu, Rui; Jaffa, Miran A; Zhao, Jingfu; Mirzaei, Parvin; Ahmed, Adnan; Kobeissy, Firas; Ziyadeh, Fuad N; Mechref, Yehia; Jaffa, Ayad A

2017-01-01

Diabetes is associated with a number of metabolic and cardiovascular risk factors that contribute to a high rate of microvascular and macrovascular complications. The risk factors and mechanisms that contribute to the development of micro- and macrovascular disease in diabetes are not fully explained. In this study, we employed mass spectrometric analysis using tandem LC-MS/MS to generate a proteomic profile of protein abundance and post-translational modifications (PTM) in the aorta and kidney of diabetic rats. In addition, systems biology analyses were employed to identify key protein markers that can provide insights into molecular pathways and processes that are differentially regulated in the aorta and kidney of type 1 diabetic rats. Our results indicated that 188 (111 downregulated and 77 upregulated) proteins were significantly identified in the aorta of diabetic rats compared to normal controls. A total of 223 (109 downregulated and 114 upregulated) proteins were significantly identified in the kidney of diabetic rats compared to normal controls. When the protein profiles from the kidney and aorta of diabetic and control rats were analyzed by principal component analysis, a distinct separation of the groups was observed. In addition, diabetes resulted in a significant increase in PTM (oxidation, phosphorylation, and acetylation) of proteins in the kidney and aorta and this effect was partially reversed by insulin treatment. Ingenuity pathway analysis performed on the list of differentially expressed proteins depicted mitochondrial dysfunction, oxidative phosphorylation and acute phase response signaling to be among the altered canonical pathways by diabetes in both tissues. The findings of the present study provide a global proteomics view of markers that highlight the mechanisms and putative processes that modulate renal and vascular injury in diabetes.

Evidence that simulated microgravity may alter the vascular nonreceptor tyrosine kinase second messenger pathway

NASA Technical Reports Server (NTRS)

Kahwaji, C. I.; Sheibani, S.; Han, S.; Siu, W. O.; Kaka, A. H.; Fathy, T. M.; el-Abbadi, N. H.; Purdy, R. E.

2000-01-01

Simulated microgravity (hind limb unweighting; HU) reduces maximal contractile capacity to norepinephrine (NE) but not 5-hydroxytryptamine (5-HT) in the rat abdominal aorta of male Wistar rats. Our earlier study showed that voltage-operated calcium channels, the MAPK pathway [1], and vasoconstrictive prostaglandins contribute to the NE-induced contraction of control (C) but not HU, aorta rings. Genistein, a general tyrosine kinase inhibitor, caused a significant reduction in vascular contractility in C but not HU arteries. The present study explored the role of protein kinase C (PKC) and extracellular receptor-activated kinase 1 and 2 (ERK1/2) in the HU-induced vascular hyporesponsiveness to NE. Microgravity was simulated in Wistar rats by 20 day HU. The abdominal aorta was removed from control and HU rats, cut into 3 mm rings, and mounted in tissue baths to measure isometric contraction. Protein levels were determined using Western blot analysis. PD98059, a selective MAPKK inhibitor, caused a marked inhibition of NE-induced contraction in both C and HU arteries. Calphostin C, a PKC inhibitor, completely abolished the contractile response to NE in both C and HU tissues. Phosphorylated (activated) ERK1/2 protein mass was greater in C, compared to HU, aortas, and was reduced by genistein only in C tissues. MAPK total protein levels in the rat aorta were increased in the HU-treated, compared to C, animals. These results indicate that PKC represents an early transduction step in the contractile response to NE in the rat abdominal aorta. That inhibition of the step immediately before activation of MAPK reduced contraction in both C and HU tissues, while general tyrosine kinase inhibition with genistein blocked only the control responses, suggests that a nonreceptor tyrosine kinase may be involved in HU-induced vascular hyporesponsiveness to NE.

[Simultaneous interventions on the ascending portion, arch of the aorta and cardiac valves in patients with Marfan's syndrome].

PubMed

Belov, Iu V; Stepanenko, A B; Gens, A P; Charchian, E R; Savichev, D D

2007-01-01

Simultaneous surgical interventions on the aorta and valvular system of the heart were performed in four patients presenting with aortic dissections and aneurysms conditioned by Marfan's syndrome. The following reconstructive operations were carried out: 1) prosthetic repair of the aortic valve and the ascending portion of the aorta by means of a valve-containing conduit with replantation of the openings of the coronary arteries into the side of the prosthesis according to the Benthall - De Bono technique, annuloplasty of the tricuspid valve according to the De Vega technique, valvuloplasty of the mitral valve by the Alferi technique; 2) grafting of the aortic valve and the ascending portion of the aorta by means of a valve-containing conduit with replantation of the openings of the coronary arteries according to the Kabrol's technique, plasty of the tricuspid valve by the De Vega technique; 3) prosthetic repair of the aortic arch with distal wedge-like excision of the membrane of the dissection and directing the blood flow along the both channels, plasty of the mitral valve, plasty of the aortic valve and the ascending portion of the aorta with a valve-containing conduit, accompanied by replantation of the openings of the coronary arteries into the side of the graft according to the Benthall - De Bono technique; (4) plasty of the mitral valve with a disk graft through the fibrous ring of the aortic valve, prosthetic repair of the aortic valve and the ascending portion of the aorta with a valve-containing conduit, accompanied by replantation of the openings of the coronary arteries into the side according to the Benthall-De Bono technique.

The anterior visceral branches of the abdominal aorta and their relationship to the renal arteries.

PubMed

Pennington, Neil; Soames, Roger W

2005-12-01

Variations in the anatomy of the abdominal aorta and its branches are of interest as vessel geometry not only determines flow dynamics, but is also crucial in the pathogenesis of vascular disease. The relationship between the anterior visceral and renal arteries is important when undertaking diagnostic arteriography and endovascular interventions. To examine these relationships, the length of the abdominal aorta was determined and measurements taken of the position of origin of the celiac artery, superior mesenteric artery (SMA), inferior mesenteric artery (IMA) and renal arteries, as well as the three-dimensional projection of each vessel from the aorta. The mean level of bifurcation of the aorta was at the lower third of the body of L4, with the celiac artery, SMA, renal arteries and IMA arising at the level of the T12/L1 intervertebral disc, upper third of the body of L1, lower third of the body of L1 and lower third of the body of L3, respectively. The horizontal projection of the celiac artery, SMA and IMA was to the left of the midline; in the sagittal plane, the celiac artery and SMA projected anteriorly and the IMA posteriorly; in the coronal plane all vessels projected inferiorly, with the SMA to the right and the IMA to the left. The celiac artery, SMA and both renal arteries all arise from the proximal half of the abdominal aorta within 45 mm of each other, with the origins of the renal arteries being remarkably consistent. It is concluded that the celiac artery and SMA are both useful landmarks for determining the position of the renal arteries.

The complementary role of magnetic resonance imaging, Doppler echocardiography, and computed tomography in the diagnosis of dissecting thoracic aneurysms.

PubMed

Goldman, A P; Kotler, M N; Scanlon, M H; Ostrum, B; Parameswaran, R; Parry, W R

1986-05-01

Non-ECG gated MRI was compared with 2DE and/or CT scans in 10 patients with dissecting aneurysms proven by angiography and/or surgery. Patient ages ranged from 48 to 85 years (mean 69.6). Six had DeBakey type I dissections and four had DeBakey type III dissections. MRI was diagnostic for aortic dissection in nine cases and suggestive in the tenth. 2DE was diagnostic in six out of nine patients, suggestive in two patients, and nondiagnostic in one patient. CT was diagnostic in the three cases in which it was employed. MRI demonstrated a dilated ascending aorta with thickened walls in all type I dissections as well as an intimal flap and slow flow in the false channel in four patients. In the other two patients with type I dissection, MRI detected the intimal flap in the descending aorta but not in the ascending aorta, whereas 2DE revealed the ascending aortic intimal flap in both of these patients and CT showed it in one of them. In the type III dissections, MRI demonstrated a thickened wall and thrombus in the lumen in all four cases, and the intimal flap in three out of the four. 2DE excluded ascending aortic involvement in all three type III dissections. Six other patients with fusiform dilated ascending aortas had no evidence of dissection by MRI, 2DE, and aortography. Thus, non-ECG gated MRI alone or in combination with 2DE and/or CT is useful in the diagnosis of dissecting thoracic aneurysm and in assessing the extent of the dissection. In addition, the differentiation of dissecting aneurysms of the aorta from fusiform dilatation of the aorta is made possible by these noninvasive techniques.

Lipid Emulsion Inhibits Vasodilation Induced by a Toxic Dose of Bupivacaine via Attenuated Dephosphorylation of Myosin Phosphatase Target Subunit 1 in Isolated Rat Aorta

PubMed Central

Ok, Seong-Ho; Byon, Hyo-Jin; Kwon, Seong-Chun; Park, Jungchul; Lee, Youngju; Hwang, Yeran; Baik, Jiseok; Choi, Mun-Jeoung; Sohn, Ju-Tae

2015-01-01

Lipid emulsions are widely used for the treatment of systemic toxicity that arises from local anesthetics. The goal of this in vitro study was to examine the cellular mechanism associated with the lipid emulsion-mediated attenuation of vasodilation induced by a toxic dose of bupivacaine in isolated endothelium-denuded rat aorta. The effects of lipid emulsion on vasodilation induced by bupivacaine, mepivacaine, and verapamil were assessed in isolated aorta precontracted with phenylephrine, the Rho kinase stimulant NaF, and the protein kinase C activator phorbol 12,13-dibutyrate (PDBu). The effects of Rho kinase inhibitor Y-27632 on contraction induced by phenylephrine or NaF were assessed. The effects of bupivacaine on intracellular calcium concentrations ([Ca2+]i) and tension induced by NaF were simultaneously measured. The effects of bupivacaine alone and lipid emulsion plus bupivacaine on myosin phosphatase target subunit 1 (MYPT1) phosphorylation induced by NaF were examined in rat aortic vascular smooth muscle cells. In precontracted aorta, the lipid emulsion attenuated bupivacaine-induced vasodilation but had no effect on mepivacaine-induced vasodilation. Y-27632 attenuated contraction induced by either phenylephrine or NaF. The lipid emulsion attenuated verapamil-induced vasodilation. Compared with phenylephrine-induced precontracted aorta, bupivacaine-induced vasodilation was slightly attenuated in NaF-induced precontracted aorta. The magnitude of the bupivacaine-induced vasodilation was higher than that of a bupivacaine-induced decrease in [Ca2+]i. Bupivacaine attenuated NaF-induced MYPT1 phosphorylation, whereas lipid emulsion pretreatment attenuated the bupivacaine-induced inhibition of MYPT1 phosphorylation induced by NaF. Taken together, these results suggest that lipid emulsions attenuate bupivacaine-induced vasodilation via the attenuation of inhibition of MYPT1 phosphorylation evoked by NaF. PMID:26664257

Effect of resveratrol and orchidectomy on the vasorelaxing influence of perivascular adipose tissue.

PubMed

Boydens, Charlotte; Pauwels, Bart; Van de Voorde, Johan

2016-04-01

Perivascular adipose tissue (PVAT) releases several adipo(cyto)kines. Some are vasoactive substances that elicit a net beneficial anticontractile effect. Resveratrol and testosterone are known to modulate adipo(cyto)kine release from adipose tissue and could therefore influence the anticontractile effect of PVAT. In vitro tension measurements were performed using thoracic aorta segments with and without adipose tissue from sham-operated or orchidectomized male Swiss mice. Concentration-response curves to norepinephrine (NOR) were constructed in the presence and absence of resveratrol (10 μM, 15 min) or the relaxant effect of resveratrol (10-100 μM) was investigated after inducing tone with NOR (5 μM). Aortas with PVAT displayed significantly attenuated contractions to NOR compared with aortas without PVAT. In aortas without PVAT, resveratrol (10 μM) significantly decreased NOR responses and elicited concentration-dependent (10-100 µM) relaxations. However, in aortas with adherent PVAT, resveratrol (10 μM) neither decreased NOR responses, nor did resveratrol (10-100 µM) induce arterial relaxations. The anticontractile effect of PVAT was less pronounced in the presence of resveratrol and unaltered by orchidectomy. Orchidectomy did not influence contractions induced by NOR. Orchidectomy does not modulate the anticontractile capacity of PVAT, while resveratrol decreases the vasorelaxing influence of PVAT. The positive effects associated with resveratrol addition are neutralized by the presence of PVAT. This is thought to result from a dual effect of resveratrol: (1) inhibition of the influence of vasodilatory adipo(cyto)kines and (2) a direct relaxant effect on the vascular smooth muscle. Overall, the beneficial relaxing effect of resveratrol is lost in mice thoracic aorta surrounded by PVAT.

Dexmedetomidine-induced Contraction Involves Phosphorylation of Caldesmon by JNK in Endothelium-denuded Rat Aortas

PubMed Central

Baik, Jiseok; Ok, Seong-Ho; Cho, Hyunhoo; Yu, Jongsun; Kim, Woochan; Nam, In-Koo; Choi, Mun-Jeoung; Lee, Heon-Keun; Sohn, Ju-Tae

2014-01-01

Caldesmon, an inhibitory actin binding protein, binds to actin and inhibits actin-myosin interactions, whereas caldesmon phosphorylation reverses the inhibitory effect of caldesmon on actin-myosin interactions, potentially leading to enhanced contraction. The goal of this study was to investigate the cellular signaling pathway responsible for caldesmon phosphorylation, which is involved in the regulation of the contraction induced by dexmedetomidine (DMT), an alpha-2 adrenoceptor agonist, in endothelium-denuded rat aortas. SP600125 (a c-Jun NH2-terminal kinase [JNK] inhibitor) dose-response curves were generated in aortas that were pre-contracted with DMT or phorbol 12,13-dibutyrate (PDBu), a protein kinase C (PKC) activator. Dose-response curves to the PKC inhibitor chelerythrine were generated in rat aortas pre-contracted with DMT. The effects of SP600125 and rauwolscine (an alpha-2 adrenoceptor inhibitor) on DMT-induced caldesmon phosphorylation in rat aortic vascular smooth muscle cells (VSMCs) were investigated by western blot analysis. PDBu-induced caldesmon and DMT-induced PKC phosphorylation in rat aortic VSMCs was investigated by western blot analysis. The effects of GF109203X (a PKC inhibitor) on DMT- or PDBu-induced JNK phosphorylation in VSMCs were assessed. SP600125 resulted in the relaxation of aortas that were pre-contracted with DMT or PDBu, whereas rauwolscine attenuated DMT-induced contraction. Chelerythrine resulted in the vasodilation of aortas pre-contracted with DMT. SP600125 and rauwolscine inhibited DMT-induced caldesmon phosphorylation. Additionally, PDBu induced caldesmon phosphorylation, and GF109203X attenuated the JNK phosphorylation induced by DMT or PDBu. DMT induced PKC phosphorylation in rat aortic VSMCs. These results suggest that alpha-2 adrenoceptor-mediated, DMT-induced contraction involves caldesmon phosphorylation that is mediated by JNK phosphorylation by PKC. PMID:25332685

Case report and review of the literature total endovascular repair of acute ascending aortic rupture: a case report and review of the literature.

PubMed

McCallum, John C; Limmer, Karl K; Perricone, Anthony; Bandyk, Dennis; Kansal, Nikhil

2013-07-01

Thoracic aortic endografting has been successfully implemented to treat aneurysmal disease of the distal aortic arch and descending thoracic aorta. Although there are reports of ascending aortic endovascular interventions, the total endovascular repair of a ruptured ascending aorta secondary to a Type A dissection has not been described. We report the case of a 77-year-old patient who presented with a ruptured ascending aortic aneurysm secondary to degeneration of a Stanford type A aortic dissection. His surgical history was significant for orthotropic heart transplant 19 years prior. The dissection, aneurysm, and rupture occurred in the native aorta distal to the ascending aortic suture line. At presentation, he was hemodynamically unstable with a right hemothorax. We placed 3 Medtronic Talent Thoracic Stent Graft devices (Medtronic Inc, Minneapolis, MN) across the suture line in the ascending aorta, excluding the rupture. The patient survived and has been followed to 25 months.

Primary Self-Expandable Nitinol Stent Placement in Focal Lesions of Infrarenal Abdominal Aorta: Long Term Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lastovickova, Jarmila, E-mail: jala@medicon.cz; Peregrin, Jan H.

Purpose. To evaluate the technical and clinical success, safety and long term results of percutaneous transluminal angioplasty/self-expandable nitinol stent placement of infrarenal abdominal aorta focal lesions. Materials and Methods. Eighteen patients underwent PTA of focal atherosclerotic occlusive disease of distal abdominal aorta. Two symptomatic occlusions and 16 stenoses in 10 male and 8 female patients (mean age 68.2 years) were treated with primary self-expandable nitinol stent placement. Results. Primary self-expandable nitinol stent placement was technically successful in all 18 procedures; clinical success was achieved in 100% of patients. No complications associated with the procedure occurred. During the 49.4 months ofmore » mean follow up (range 3-96, 4 months) all treated aortic segments remained patent. Conclusions. Endovascular treatment (primary self-expandable nitinol stent placement) of focal atherosclerotic lesions of distal abdominal aorta is a safe method with excellent primary technical and clinical success rates and favourable Long term results.« less

Endovascular Repair of Contained Rupture of the Thoracic Aorta

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morgan, Robert; Loosemore, Tom; Belli, Anna-Maria

Purpose: To assess the efficacy of stent-grafts for the treatment of acute rupture of the thoracic aorta. Methods: Four patients with acute contained ruptures of the thoracic aorta were treated by insertion of stent-grafts. The underlying aortic lesions were aneurysm, acute aortic ulcer, acute type B dissection and giant cell aortitis. The procedures were performed under general anesthesia in three patients and local anesthesia in one patient. Results: All stent-grafts were successfully deployed. All patients survived the procedure and are now alive and well at follow-up (mean 6.3 months, range 44 days-16 months). One patient underwent a second stent proceduremore » 10 days after the first procedure because of a proximal endoleak. All hemothoraces have resolved. There were no complications. Conclusion:Treatment of acute contained ruptures of the thoracic aorta by the insertion of stent-grafts is feasible. The technical success rates,complication rates and patient survival compare favorably with emergency surgery.« less

Landmark lecture: Perloff lecture: Tribute to Professor Joseph Kayle Perloff and lessons learned from him: aortopathy in adults with CHD.

PubMed

Niwa, Koichiro

2017-12-01

Marfan syndrome, bicuspid aortic valve, and/or coarctation of the aorta are associated with medial abnormalities of the ascending aortic or para-coarctation aorta. Medial abnormalities in the ascending aorta are prevalent in other type of patients with a variety of CHDs such as single ventricle, persistent truncus arteriosus, transposition of the great arteries, hypoplastic left heart syndrome, and tetralogy of Fallot, encompassing a wide age range and may predispose to dilatation, aneurysm, and rapture necessitating aortic valve and root surgery. These CHDs exhibit ongoing dilatation of the aortic root and reduced aortic elasticity and increased aortic stiffness that may relate to intrinsic properties of the aortic root. These aortic dilatation and increased stiffness can induce aortic aneurysm, rapture of the aorta, and aortic regurgitation, but also provoke left ventricular hypertrophy, reduced coronary artery flow, and left ventricular failure. Therefore, a new clinical entity can be used to call this association of aortic pathophysiological abnormality, aortic dilation, and aorto-left ventricular interaction - "aortopathy".

Numerical analysis of wall shear stress in ascending aorta before tearing in type A aortic dissection.

PubMed

Chi, Qingzhuo; He, Ying; Luan, Yong; Qin, Kairong; Mu, Lizhong

2017-10-01

Although the incidence of many cardiovascular diseases has declined as medical treatments have improved, the prevalence of aortic dissection (AD) has increased. Compared to type B dissections, type A dissections are more severe, and most patients with type A dissections require surgical treatment. The objective of this study was to investigate the relationships between the wall shear stress (WSS) on the aortic endothelium and the frequent tearing positions using computational fluid dynamics. Five type A dissection cases and two normal aortas were included in the study. First, the structures of the aortas before the type A dissection were reconstructed on the basis of the original imaging data. Analyses of flow in the reconstructed premorbid structures reveals that the rupture positions in three of the five cases corresponded to the area of maximum elevated WSS. Moreover, the WSS at the junction of the aortic arch and descending aorta was found to be elevated, which is considered to be related to the locally disturbed helical flow. Meanwhile, the highest WSS in the patients with premorbid AD was found to be almost double that of the control group. Due to the noticeable morphological differences between the AD cases and the control group, the WSSs in the premorbid structures without vasodilation in the ascending part were estimated. The computational results revealed that the WSS was lower in the aorta without vasodilation, but the pressure drop in this situation was higher than that with vasodilation in the ascending aorta. Significant differences were seen between the AD cases and the control group in the angles of the side branches of the aortic arch and its bending degree. Dilation of the ascending aorta and alterations in the branching angles may be the key determinants of a high WSS that leads to type A dissection. Greater tortuosity of the aortic arch leads to stronger helical flow through the distal aortic arch, which may be related to tears in this region. Copyright © 2017 Elsevier Ltd. All rights reserved.

The risk of stanford type-A aortic dissection with different tear size and location: a numerical study.

PubMed

Shi, Yue; Zhu, Minjia; Chang, Yu; Qiao, Huanyu; Liu, Yongmin

2016-12-28

This study is to investigate the influence of hemodynamics on Stanford type-A aortic dissection with different tear size and location, to provide some support for the relationships between the risks (rupture, reverse tearing and further tearing) and tear size and location for clinical treatment. Four numerical models of Stanford type-A aortic dissection were established, with different size and location of the tears. The ratio of the area between the entry and re-entry tears(RA) is various within the model; while, the size and the location of the re-entry in the distal descending aorta are fixed. In model A11 and A21, the entry tears are located near the ascending aorta. The RA in these models are 1 and 2, respectively; In the model B11 and B21, the entry tears are located near the proximal descending aorta and the RA in these models are again assigned to 1 and 2, respectively. Then hemodynamics in these models was solved with numerically and the flow patterns and loading distributions were investigated. The flow velocity of the true lumen in model A21, B21 is lower than that in A11, B11, respectively; the time-averaged wall shear stress (TAWSS) of the false lumen in model A21 and B21 is higher, and for ascending aorta false lumen, A11, A21 are higher than B11, B21, respectively. False lumen intimal wall pressure of A11, A21 are always higher than the true lumen ones. The variation of the RA can significantly affect the dynamics of blood within the aortic dissection. When the entry tear size is larger than the re-entry tear ones, the false lumen, proximal descending aorta and the wall near re-entry tear are prone to cracking. Entry tear location can significantly alter the hemodynamics of aortic dissection as well. When entry tear location is closer to proximal ascending aorta, false lumen continues to expand and compress the true lumen resulting in the true lumen reduction. For proximal ascending aorta, high pressure in false lumen predicts a higher risk of reverse tear.

Percutaneous Implantation of the self-expanding valve Prosthesis a patient with homozygous familial hypercholesterolemia severe aortic stenosis and porcelain aorta.

PubMed

Sahiner, Levent; Asil, Serkan; Kaya, Ergün Baris; Ozer, Necla; Aytemir, Kudret

2016-10-01

Transcatheter aortic valve implantation (TAVI) has shown favorable outcomes in patients with severe symptomatic aortic valve stenosis who are at high surgical risk or inappropriate for open heart surgery. However, concerns exist over treating patients who have porcelain aorta and familial hypercholesterolemia, due to the potential complications of aortic root and aortic annulus. In this case report, we present a patient with familial hypercholesterolemia, symptomatic severe aortic stenosis, previous coronary artery bypass grafting and porcelain aorta, who was successfully treated with TAVI using a CoreValve. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Descending aorta-external iliac artery bypass for middle aortic syndrome.

PubMed

Okamoto, Yuki; Yamamoto, Kazuo; Sugimoto, Tsutomu; Asami, Fuyuki; Nagasawa, Ayako; Shiraiwa, Satoru; Nakamura, Norihito; Yoshii, Shinpei

2014-11-01

We encountered a surgical case of middle aortic syndrome (MAS) in a 56-year-old man who had resistant hypertension. Computed tomography showed severe stenosis of the abdominal aorta from below the superior mesenteric artery to above the inferior mesenteric artery. Although bilateral renal artery stenosis was confirmed, renal function was within normal limits. A 10-mm vascular prosthetic graft was used to perform a descending aorta to left external iliac artery bypass. His hypertension was well controlled without medication. This extra-anatomic bypass may be a simple and useful approach for treating MAS if it is not necessary to reconstruct the renal artery or visceral artery.

[Pathophysiology, prophylaxis and treatment of reperfusion syndrome in the surgery of abdominal aorta aneurysm].

PubMed

Sukharev, I I; Guch, A A; Medvedskyĭ, E B; Kostylev, M V; Kornitskaia, A I; Gindich, L A; Dominiak, A B; Vlaĭkov, G G

1999-01-01

The peroxidal oxidation of the lipids state was studied up, as well as of the whole blood neutrophils functional activity, hemodynamics and microcirculation of lower extremities in surgical treatment of the abdominal aorta aneurysm. The main significance in the reperfusional syndrome pathophysiology, caused by temporary overcompression of aorta, has the neutrophils activation, their interrelationship with the endothelium cells and the activity lowering of the tissue antioxidant system, manifestated by vascular spasm, which is mostly expressed in the patients with stenotic affection of the lower extremities arteries. Positive effect was noted in application of preparation corvitin, which has antioxidant action.

Optical coherence elastography for cellular-scale stiffness imaging of mouse aorta

NASA Astrophysics Data System (ADS)

Wijesinghe, Philip; Johansen, Niloufer J.; Curatolo, Andrea; Sampson, David D.; Ganss, Ruth; Kennedy, Brendan F.

2017-04-01

We have developed a high-resolution optical coherence elastography system capable of estimating Young's modulus in tissue volumes with an isotropic resolution of 15 μm over a 1 mm lateral field of view and a 100 μm axial depth of field. We demonstrate our technique on healthy and hypertensive, freshly excised and intact mouse aortas. Our technique has the capacity to delineate the individual mechanics of elastic lamellae and vascular smooth muscle. Further, we observe global and regional vascular stiffening in hypertensive aortas, and note the presence of local micro-mechanical signatures, characteristic of fibrous and lipid-rich regions.

Targeting the Nociceptin/Orphanin FQ Receptor for Scleroderma Therapy

DTIC Science & Technology

2016-08-01

quantified by flow cytometry. In the aortic ring assay, freshly isolated thoracic aorta rings will be harvested and mounted in a small- vessel...ring assay, freshly isolated thoracic aorta rings will be harvested and mounted in a small-vessel myograph. Vasodilation will be determined by

Surgical exclusion of postsurgical pseudoaneurysm of the ascending aorta

PubMed Central

Barik, Ramachandra; Patnaik, Amar Narayana; Kumar, Ravintula Venkata; Mohapatra, Rudra Prasad; Medep, Vikas; Nemani, Lalita

2014-01-01

Pseudoaneurysm of ascending aorta after cardiac surgery is rare in children. We report a case of successful surgical exclusion of ascending aortic pseudoaneurysm in a 15-year-old boy. The neck of the aneurysm was in close proximity to the right coronary artery (RCA). PMID:24987261

In-vivo and in-situ detection of atherosclerotic plaques using full-range complex-conjugate-free spectral domain optical coherence tomography in the murine carotid

NASA Astrophysics Data System (ADS)

Huang, Yong; Wicks, Robert; Zhang, Kang; Zhao, Mingtao; Tyler, Betty M.; Hwang, Lee; Pradilla, Gustavo; Kang, Jin U.

2013-03-01

Carotid endarterectomy is a common vascular surgical procedure which may help prevent patients' risk of having a stroke. A high resolution real-time imaging technique that can detect the position and size of vascular plaques would provide great value to reduce the risk level and increase the surgical outcome. Optical coherence tomography (OCT), as a high resolution high speed noninvasive imaging technique, was evaluated in this study. Twenty-four 24-week old apolipoprotein E-deficient (ApoE-/-) mice were divided into three groups with 8 in each. One served as the control group fed with normal diet. One served as the study group fed with high-fat diet to induce atherosclerosis. The last served as the treatment group fed with both high-fat diet and medicine to treat atherosclerosis. Full-range, complex-conjugate-free spectral-domain OCT was used to image the mouse aorta near the neck area in-vivo with aorta exposed to the imaging head through surgical procedure. 2D and 3D images of the area of interest were presented real-time through graphics processing unit accelerated algorithm. In-situ imaging of all the mice after perfusion were performed again to validate the invivo detection result and to show potential capability of OCT if combined with surgical saline flush. Later all the imaged arteries were stained with H and E to perform histology analysis. Preliminary results confirmed the accuracy and fast imaging speed of OCT imaging technique in determining atherosclerosis.

Aortic annulus and ascending aorta: comparison of preoperative and periooperative measurement in patients with aortic stenosis.

PubMed

Smíd, Michal; Ferda, Jirí; Baxa, Jan; Cech, Jakub; Hájek, Tomás; Kreuzberg, Boris; Rokyta, Richard

2010-04-01

Precise determination of the aortic annulus size constitutes an integral part of the preoperative evaluation prior to aortic valve replacement. It enables the estimation of the size of prosthesis to be implanted. Knowledge of the size of the ascending aorta is required in the preoperative analysis and monitoring of its dilation enables the precise timing of the operation. Our goal was to compare the precision of measurement of the aortic annulus and ascending aorta using magnetic resonance (MR), multidetector-row computed tomography (MDCT), transthoracic echocardiography (TTE), and transoesophageal echocardiography (TEE) in patients with degenerative aortic stenosis. A total of 15 patients scheduled to have aortic valve replacement were enrolled into this prospective study. TTE was performed in all patients and was supplemented with TEE, CT and MR in the majority of patients. The values obtained were compared with perioperative measurements. For the measurement of aortic annulus, MR was found to be the most precise technique, followed by MDCT, TTE, and TEE. For the measurement of ascending aorta, MR again was found to be the most precise technique, followed by MDCT, TEE, and TTE. In our study, magnetic resonance was found to be the most precise technique for the measurement of aortic annulus and ascending aorta in patients with severe degenerative aortic stenosis. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Computational analysis of aortic hemodynamics during total and partial extracorporeal membrane oxygenation and intra-aortic balloon pump support.

PubMed

Caruso, Maria Vittoria; Gramigna, Vera; Renzulli, Attilio; Fragomeni, Gionata

2016-01-01

The extracorporeal membrane oxygenation (ECMO) is a temporary, but prolonged circulatory support for cardiopulmonary failure. Clinical evidence suggests that pulsed flow is healthier than non pulsatile perfusion. The aim of this study was to computationally evaluate the effects of total and partial ECMO assistance and pulsed flow on hemodynamics in a patient-specific aorta model. The pulsatility was obtained by means of the intra-aortic balloon pump (IABP), and two different cases were investigated, considering a cardiac output (CO) of 5 L/min: Case A - total assistance - the whole flow delivered through the ECMO arterial cannula; Case B - partial assistance - flow delivered half through the cannula and half through the aorta. Computational fluid dynamic (CFD) analysis was carried out using the multiscale approach to couple the 3D aorta model with the lumped parameter model (resistance boundary condition). In case A pulsatility followed the balloon radius change, while in case B it was mostly influenced by the cardiac one. Furthermore, during total assistance, a blood stagnation occurred in the ascending aorta; in the case of partial assistance, the flow was orderly when the IABP was on and was chaotic when the balloon was off. Moreover, the mean arterial pressure (MAP) was higher in case B. The wall shear stress was worse in ascending aorta in case A. Partial support is hemodynamically advisable.

The action of diazoxide and minoxidil sulphate on rat blood vessels: a comparison with cromakalim.

PubMed Central

Newgreen, D. T.; Bray, K. M.; McHarg, A. D.; Weston, A. H.; Duty, S.; Brown, B. S.; Kay, P. B.; Edwards, G.; Longmore, J.; Southerton, J. S.

1990-01-01

1. The actions of diazoxide and minoxidil sulphate have been compared with those of cromakalim in rat aorta and portal vein. 2. Diazoxide and minoxidil sulphate hyperpolarized the rat portal vein in a similar manner to cromakalim. 3. Cromakalim, diazoxide and minoxidil sulphate increased 42K and 86Rb efflux from rat portal vein, although minoxidil sulphate had only a small effect on 86Rb efflux. 4. Cromakalim, diazoxide and minoxidil sulphate increased 42K efflux from rat aorta but only cromakalim and diazoxide increased 86Rb efflux from this tissue. 5. Glibenclamide inhibited the relaxant actions of cromakalim, diazoxide and minoxidil sulphate on rat aorta and the increase in 42K efflux produced by these agents in this tissue. 6. Diazoxide relaxed an 80 mM KCl-induced contraction of rat aorta, whilst cromakalim and minoxidil sulphate were without effect. 7. Cromakalim, diazoxide and minoxidil sulphate had no effect on cyclic AMP or cyclic GMP concentrations in rat aorta. 8. It is concluded that diazoxide and minoxidil sulphate like cromakalim exhibit K+ channel opening properties in vascular smooth muscle. Diazoxide exerts an additional inhibitory action not related to the production of cyclic AMP or cyclic GMP. The action of minoxidil sulphate may be primarily located at a K+ channel which is relatively impermeable to 86Rb. PMID:2167738

Cholesterol uptake in the mouse aorta increases during Chlamydia pneumoniae infection.

PubMed

Edvinsson, Marie; Tallkvist, Jonas; Nyström-Rosander, Christina; Ilbäck, Nils-Gunnar

2017-01-01

Chlamydia pneumoniae has been suggested as a stimulator of the atherosclerotic process. Mice fed a normal diet were infected intranasally with C. pneumoniae and given one intraperitoneal injection of 14C-cholesterol tracer per day for 12 days. Bacteria were demonstrated in the aorta in the early phase of infection and in lungs and liver throughout the study period of 20 days. 14C-cholesterol was not affected in the heart but increased in the blood, liver and aorta on day 4 when the infection was clinically most severe. Furthermore, on day 20 14C-cholesterol tended to be increased in the aorta. Accordingly, copper- and zinc levels and expressions of the infection biomarkers Cxcl2 and Ifng increased in the liver on day 4 with a tendency of increased of copper, zinc and Ifng on day 20. In mice where bacteria could be cultivated from the lungs, expressions of cholesterol transporters Abca1 and Idol were both increased in the liver on day 4. The increased levels of 14C-cholesterol in blood and aorta together with increased Abca1 and Idol in the liver during C. pneumoniae infection in mice fed a normal diet suggest that this pathogen may have a role in the initiation of the atherosclerotic process. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Combined modified en bloc corpectomy with replacement of the aorta in curative interdisciplinary treatment of a large osteosarcoma infiltrating the aorta.

PubMed

Pilger, Amrei; Tsilimparis, Nikolaos; Bockhorn, Maximilian; Trepel, Martin; Dreimann, Marc

2016-05-01

We report a case of a large three-level spinal osteosarcoma infiltrating the adjacent aorta. This is the first case in which a combined modified three-level en bloc corpectomy with resection and replacement of the adjacent aorta was successful as a part of interdisciplinary curative treatment. Case report. The surgical procedure was performed as a two-step treatment. A heart lung machine (HLM) was not used, in order to avoid cerebral and spinal ischemia and to decrease the risk of hematogenous tumor metastases. Instead, a bypass from the left subclavian artery the distal descending aorta was used. We modified the en bloc corpectomy procedure, leaving a dorsal segment of the vertebral bodies to enable rapid surgery. The procedure was successful and the en bloc resection of the vertebral body with aortal resection could be achieved. Except for pallhypesthesia in the left dermatomes Th7-Th10, the patient does not have any postoperative neurologic deficits. Combined corpectomy with aortic replacement should be considered as a reasonable option in the curative treatment of osteosarcoma with consideration of the immense surgical risks. The use of an HLM is not necessary, especially considering the inherent risk of hematogenous tumor metastases. Modified corpectomy leaving a dorsal vertebral body segment was considered a reasonable variation since tumor-free margins could still be expected.

The role of endothelium in the vasorelaxant effects of the essential oil of Ocimum gratissimum in aorta and mesenteric vascular bed of rats.

PubMed

Pires, Alana F; Madeira, Socorro V Frota; Soares, Pedro M G; Montenegro, Claudia M; Souza, Emmanuel P; Resende, Angela C; Soares de Moura, Roberto; Assreuy, Ana M S; Criddle, David N

2012-10-01

This study investigated the endothelium-dependent vasorelaxant effects of the essential oil of Ocimum gratissimum (EOOG) in aortas and mesenteric vascular beds isolated from rats. EOOG (3-300 µg/mL) relaxed the tonic contractions induced by phenylephrine (0.1 µmol/L) in isolated aortas in a concentration-dependent manner in both endothelium-containing and endothelium-denuded preparations. This effect was partially reversed by L-NAME (100 µmol/L) but not by indomethacin (10 µmol/L) or TEA (5 mmol/L). In mesenteric vascular beds, bolus injections of EOOG (30, 50, 100, and 300 ng) decreased the perfusion pressure induced by noradrenaline (6 µmol/L) in endothelium-intact preparations but not in those treated with deoxycholate. L-NAME (300 µmol/L) but not TEA (1 mmol/L) or indomethacin (3 µmol/L) significantly reduced the vasodilatory response to EOOG at all of the doses tested. Our data showed that EOOG exerts a dose-dependent vasodilatory response in the resistance blood vessels of rat mesenteric vascular beds and in the capacitance blood vessel, the rat aorta. This action is completely dependent on endothelial nitric oxide (NO) release in the mesenteric vascular beds but only partially dependent on NO in the aorta. These novel effects of EOOG highlight interesting differences between resistance and capacitance blood vessels.

Mechanisms of vasodilation in the dorsal aorta of the elephant fish, Callorhinchus milii (Chimaeriformes: Holocephali).

PubMed

Jennings, Brett L; Bell, Justin D; Hyodo, Susumu; Toop, Tes; Donald, John A

2007-07-01

This study investigated vasodilator mechanisms in the dorsal aorta of the elephant fish, Callorhinchus milii, using anatomical and physiological approaches. Nitric oxide synthase could only be located in the perivascular nerve fibres and not the endothelium of the dorsal aorta, using NADPH histochemistry and immunohistochemistry. In vitro organ bath experiments demonstrated that a NO/soluble guanylyl cyclase (GC) system appeared to be absent in the vascular smooth muscle, since the NO donors SNP (10(-4) mol l(-1)) and SIN-1 (10(-5) mol l(-1)) were without effect. Nicotine (3 x 10(-4) mol l(-1)) mediated a vasodilation that was not affected by ODQ (10(-5) mol l(-1)), L-NNA (10(-4) mol l(-1)), indomethacin (10(-5) mol l(-1)), or removal of the endothelium. In contrast, the voltage-gated sodium channel inhibitor, tetrodotoxin (10(-5) mol l(-1)), significantly decreased the dilation induced by nicotine, suggesting that it contained a neural component. Pre-incubation of the dorsal aorta with the calcitonin gene-related peptide (CGRP) receptor antagonist, CGRP(8-37) (10(-6) mol l(-1)) also caused a significant decrease in the nicotine-induced dilation. We propose that nicotine is mediating a neurally-derived vasodilation in the dorsal aorta that is independent of NO, prostaglandins and the endothelium, and partly mediated by CGRP.

[3D echocardiography of the ascending aorta in Marfan's syndrome].

PubMed

Dulac, Y; Taktak, A; Acar, P; Abadir, S; Chilon, T; Edouard, T; Julia, S; Tauber, M; Hovnanian, A

2005-05-01

Marfan's syndrome is a cause of dilatation of the aorta, the main complication of which is dissection of the aorta. 2D echocardiography is the reference investigation for measuring the ascending aorta. Asymmetry of sinus dilatation makes a 3D approach necessary. Real time 3D echocardiography is a simple, non-invasive method which, by a biplane mode, allows measurement of the 3 sinuses of Valsalva. The aim of the study was to compare the 2D and 3D echocardiographic methods for measuring the ascending aorta. Fifteen patients (average age 12 +/- 8 years) with Marfan's syndrome were studied prospectively. The maximal 3D diameter was significantly greater than the 2D measurement (31.7 +/- 6.8 mm vs 29.9 +/- 6.6 mm, p< 0.005). In 4 patients, the difference was over 3 mm. The diameter between the right coronary and left coronary sinus was greater than the two others (right coronary-non coronary and left coronary-non coronary). The oldest 5 patients had an MRI aortic measurement very similar to that of 3D echocardiography (36.6 vs 36.7 mm). Real time 3D echocardiography in the biplane mode enables reliable and reproducible measurement of the aortic root in patients with Marfan's syndrome. Larger and multicenter studies are required to allow confirmation of the value of 3D echocardiography in the follow-up of these patients.

False positive computed tomographic angiography for Stanford type A aortic dissection.

PubMed

Bandali, Murad F; Hatem, Muhammed A; Appoo, Jehangir J; Hutchison, Stuart J; Wong, Jason K

2015-12-01

Computed tomographic angiography (CTA) has emerged as the defacto imaging test to rule out acute aortic dissection; however, it is not without flaws. We report a case of a false-positive CTA with respect to Stanford Type A aortic dissection. A 52 year-old male presented with sudden onset shortness of breath. He denied chest pain. Due to severe hypertension and an Emergency Department bedside ultrasound suggesting an intimal flap in the aorta, CTA was requested to better assess the ascending aorta and was interpreted as consistent with Stanford Type A aortic dissection with thrombosis of the false lumen in the ascending aorta. However, intra-operative imaging (TEE and epi-aortic scanning) did not identify an intimal flap or dissection, and neither did definitive surgical inspection of the aorta. The suspected aortic dissection and thrombosed false lumen were not visualized on repeat CTA two days later. False positive diagnosis of Stanford Type A aortic dissection on CTA can be the result of technical factors, streak artifacts, motion artifacts, and periaortic structures. In this case, non-uniform arterial contrast enhancement secondary to unrecognized biventricular dysfunction resulted in the false positive CTA appearance of an intimal flap and mural thrombus. Intra-operative TEE and epi-aortic scanning were proven correct in excluding aortic dissection by the standard of definitive surgical inspection of the aorta.