Search results for "Endocardium"
showing 10 items of 21 documents
Inhomogeneity of collagen organization within the fibrotic scar after myocardial infarction: results in a swine model and in human samples.
2015
We aimed to characterize the organization of collagen within a fibrotic scar in swine and human samples from patients with chronic infarctions. Swine were subjected to occlusion of the left anterior descending artery followed by reperfusion 1 week (acute myocardial infarction group) or 1 month (chronic myocardial infarction group) after infarction. The organization of the collagen fibers (Fast Fourier Transform of samples after picrosirius staining; higher values indicate more disorganization) was studied in 100 swine and 95 human samples. No differences in collagen organization were found between the acute and chronic groups in the core area of the scar in the experimental model. In the ch…
Noncompaction of the Right Ventricle
2010
Noncompaction of the ventricular myocardium is a disease characterized by an increase of the ventricular trabecular meshwork caused by arrest of the normal endomyocardial morphogenesis (Figs. 1, 2, 3). In accordance with the normal human anatomy, the left ventricular wall is well compacted with a few thin trabeculae; on the contrary, the normal right ventricular wall is furrowed by many trabeculae (the trabecula of the marginal septum as well as other ones). For this reason, the term ‘‘noncompaction’’ usually refers to an exclusive or prevalent disease of the left ventricle [1–16]. Recently Song and Aragona et al. [1–3] reported two cases of isolated right-ventricular noncompaction. Accordi…
Low-energy epicardial pacing in children: the benefit of autocapture.
1999
Abstract Background . Permanent cardiac pacing in children results commonly in augmented energy consumption because of the high pacing rates and the ample stimulation safety margin applied in children. Cardiovascular anatomy and limited venous access sometimes preclude the otherwise preferred endocardial approach. In this multicenter patient series, we studied the feasibility, safety, and energy saving obtained by a combination of steroid-eluting epicardial leads with autocapture devices capable of ongoing adjustment of the stimulation output to the prevailing threshold. Methods . Autocapture devices (Pacesetter Microny SR+ and Regency SR+; Pacesetter, Solna, Sweden) and steroid-eluting epi…
Isolation and characterization of pluripotent cells from the subendocardial layer of human hearts from chronic heart failure.
2008
Purpose: Several literature reports indicated the existence of pluripotent cells residing into the heart wall, even if in vivo heart regeneration is still a poorly comprised phenomenon. Post-infarct chronic heart failure is a pathology for which heart transplant remains a key option of clinical intervention. The amount of data collected in recent years forces researchers to better characterize the properties of adult stem cells, especially for those isolated from heart. Methods: We developed a new protocol to obtain, from the subendocardial layer of post-infarct hearts explanted from chronic heart failure patients undergoing heart transplantation, populations of mesenchymal stem cells. The …
Oxidative stress-driven expression of myeloperoxidase in endothelial cells results in accumulation of markers of oxidative and nitrosative stress in …
2009
Endothelial cells (ECs), are able to manage with higher concentrations of ROS as well as reactive nitrogen species, respect to the other cell types. The unbalance between oxidizing species and antioxidant cellular defences has been implicated in the pathogenesis of cardiovascular diseases. While the role of MPO in the oxidative burst is well established, the effects of this enzyme on endothelial biology have only recently come to light. MPO can interact with endothelial –derived NO causing its depletion and favouring its conversion to nitrogen dioxide radical, a compound responsible of protein nitration generating 3-nitrotyrosine. Moreover, MPO is the only enzyme capable to form hypoclorous…
Hyperplastic Conotruncal Endocardial Cushions and Transposition of Great Arteries in Perlecan-Null Mice
2002
Perlecan is a heparan-sulfate proteoglycan abundantly expressed in pericellular matrices and basement membranes during development. Inactivation of the perlecan gene in mice is lethal at two developmental stages: around E10 and around birth. We report a high incidence of malformations of the cardiac outflow tract in perlecan-deficient embryos. Complete transposition of great arteries was diagnosed in 11 out of 15 late embryos studied (73%). Three of these 11 embryos also showed malformations of semilunar valves. Mesenchymal cells in the outflow tract were abnormally abundant in mutant embryos by E9.5, when the endocardial-mesenchymal transformation starts in wild-type embryos. At E10.5, mut…
A Rule-Based Method to Model Myocardial Fiber Orientation for Simulating Ventricular Outflow Tract Arrhythmias
2017
Comunicació presentada a: FIMH 2017 9th International Conference, celebrada a Toronto, Canadà, de l'11 al 13 de juny de 2017. Myocardial fiber orientation determines the propagation of electrical waves in the heart and the contraction of cardiac tissue. One common approach for assigning fiber orientation to cardiac anatomi- cal models are Rule-Based Methods (RBM). However, RBM have been developed to assimilate data mostly from the Left Ventricle. In conse- quence, fiber information from RBM does not match with histological data in other areas of the heart, having a negative impact in cardiac simulations beyond the LV. In this work, we present a RBM where fiber orientation is separately mode…
Left ventricular volume determination using colour superpositioning of contrast echocardiograms
1995
Abstract Objective: To delineate the endocardium, selective colouring of contrast regions in left ventricular contrast echocardiograms was performed using digital image processing. Methods: Volume determinations were performed in end-diastolic and end-systolic frames before and after the injection of contrast agent into the left ventricle and were compared to cineventriculograms in 30 patients by two independent investigators. Results: The mean end-diastolic volume measured was 114 ± 44 ml in the native, 235 ± 79 ml in the contrast, 175 ± 70 ml in the color-superimposed (observer 1), and 187 ± 79 ml in the cineventriculographic images. Thus, native echocardiograms underestimated angiographi…
1232 Acute myocarditis: prognostic role of speckle tracking echocardiography and cardiac magnetic resonance
2020
Abstract Background Myocarditis is an inflammatory disease of the myocardium predominantly caused by infection with subsequent immunological response. Cardiac magnetic resonance (CMR) is the currently best imaging modality to confirm a suspected diagnosis of myocarditis. Conventional echocardiography can detect regional or global wall motion abnormalities but it could also be negative. Speckle tracking echocardiography can help to identify subtle systolic dysfunction, in patients with myocardits and apparently negative echocardiogram. Purpose the aim of this study was to identify cardiac imaging parameters predictive of cardiovascular events in patients with acute myocarditis. Methods a pro…
Oxidative stress induces myeloperoxidase expression in endocardial endothelial cells from patients with chronic heart failure.
2009
Increased oxidative stress has been implicated in the pathogenesis of a number of cardiovascular diseases. Recent findings suggest that myeloperoxidase (MPO) may play a key role in the initiation and maintenance of chronic heart failure (CHF) by contributing to the depletion of the intracellular reservoir of nitric oxide (NO). NO consumption through MPO activity may lead to protein chlorination or nitration, leading to tissue damage. Primary cultures of human endocardial endothelial cells (EEC) obtained at heart transplantation of patients with CHF and human umbilical vein endothelial cells (HUVEC) were subjected to oxidative stress by incubation with hydrogen peroxide at non lethal (60 mic…