Search results for "Myocardium"

Prognostic Role of Late Gadolinium Enhancement in Patients With Hypertrophic Cardiomyopathy and Low-to-Intermediate Sudden Cardiac Death Risk Score

2019

Sudden cardiac death (SCD) is the most life-threating complication of hypertrophic cardiomyopathy. Guidelines of the European Society of Cardiology (ESC) suggest the implantation of an implantable cardioverter defibrillator in primary prevention according to a 5-year risk SCD score >= 6%. The aim of the study is to evaluate the prognostic role of late gadolinium enhancement (LGE) in patients with a 5-year risk SCD score <6%. In this multicenter study, we performed cardiac magnetic resonance in 354 consecutive hypertrophic cardiomy-opathy patients (257 males, range of age 54 +/- 17) with a risk SCD score <6% (302 with <4% and 52 with >= 4 and <6% risk). Hard cardiac events,…

Cardiac Injury in COVID-19–Echoing Prognostication∗

2020

Background Myocardial injury is frequent among patients hospitalized with coronavirus disease-2019 (COVID-19) and is associated with a poor prognosis. However, the mechanisms of myocardial injury remain unclear and prior studies have not reported cardiovascular imaging data. Objectives This study sought to characterize the echocardiographic abnormalities associated with myocardial injury and their prognostic impact in patients with COVID-19. Methods We conducted an international, multicenter cohort study including 7 hospitals in New York City and Milan of hospitalized patients with laboratory-confirmed COVID-19 who had undergone transthoracic echocardiographic (TTE) and electrocardiographic…

Nebivolol inhibits superoxide formation by NADPH oxidase and endothelial dysfunction in angiotensin II-treated rats.

2006

Nebivolol is a β 1 -receptor antagonist with vasodilator and antioxidant properties. Because the vascular NADPH oxidase is an important superoxide source, we studied the effect of nebivolol on endothelial function and NADPH oxidase activity and expression in the well-characterized model of angiotensin II–induced hypertension. Angiotensin II infusion (1 mg/kg per day for 7 days) caused endothelial dysfunction in male Wistar rats and increased vascular superoxide as detected by lucigenin-derived chemiluminescence, as well as dihydroethidine staining. Vascular NADPH oxidase activity, as well as expression at the mRNA and protein level, were markedly upregulated, as well as NOS III uncoupled, …

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…

Spiral wave induced numerically using electrical stimulation and comparison with experimental results.

2010

Experiments in vitro on a Microelectrode Array (MEA) platform show that electrical stimulation can provoke the generation of spiral waves in cardiac tissue. Nevertheless, the conditions leading to this artificial fibrillation state remain unclear. In order to have a better understanding of this phenomenon, a numerical simulation study has been conducted. The results obtained with a two-dimensional FitzHugh-Nagumo model proved that it is possible to create spiral waves by adding a stimulation current under certain conditions, which are made explicit.

Polycaprolactone/gelatin-based scaffolds with tailored performance: in vitro and in vivo validation

2019

Abstract Nanofibrous scaffolds composed of polycaprolactone (PCL) and gelatin (Ge) were obtained through a hydrolytic assisted electrospinning process. The PCL-to-Ge proportion (100/0 to 20/80), as well as the dissolution time (24, 48, 72, 96, 120 h) into a 1:1 formic/acetic acid solvent before electrospinning were modified to obtain the different samples. A strong influence of these factors on the physicochemical properties of the scaffolds was observed. Higher Ge percentage reduced crystallinity, allowed a uniform morphology and increased water contact angle. The increase in the dissolution time considerably reduced the molar mass and, subsequently, fibre diameter and crystallinity were a…

Lipomatous Metaplasia. Two Chronic Infarcts in the Same Patient Detected by Cardiac Magnetic Resonance

2009

Virus-receptor interactions of coxsackie B viruses and their putative influence on cardiotropism

2003

Specific virus-receptor interactions are important determinants in the pathogenesis of viral infections, influencing the location and initiation of primary infection as well as the viral spread to other target organs in the postviremic phase. Coxsackieviruses of group B (CVB) specifically interact with at least two receptor proteins, the coxsackievirus-adenovirus receptor (CAR) and the decay-accelerating factor (DAF), and cause a broad spectrum of diseases, including acute and chronic myocarditis. In the human heart, CAR is predominantly expressed in intercalated discs, regions of utmost importance for the functional integrity of the heart. Since DAF is abundantly expressed in epithelial an…

Cytochrome c in a Dry Trehalose Matrix: Structural and Dynamical Effects Probed by X-Ray Absorption Spectroscopy

2007

AbstractWe report on the structure and dynamics of the Fe ligand cluster of reduced horse heart cytochrome c in solution, in a dried polyvinyl alcohol (PVA) film, and in two trehalose matrices characterized by different contents of residual water. The effect of the solvent/matrix environment was studied at room temperature using Fe K-edge x-ray absorption fine structure (XAFS) spectroscopy. XAFS data were analyzed by combining ab initio simulations and multi-parameter fitting in an attempt to disentangle structural from disorder parameters. Essentially the same structural and disorder parameters account adequately for the XAFS spectra measured in solution, both in the absence and in the pre…

Different intracellular cation-content present in right and left ventricle dependent on varying extracellular Ca2+-concentrations.

1979

Abstract The different intracellular cation-contents present in the right and left ventricle depend on varying Ca2+-concentrations. The effect of extracellular Ca2+-concentrations varied within the physiological range has been studied on an isolated guinea pig heart preparation, showing excellent stable experimental conditions. By increasing the extracellular Ca2+-concentration from 0.45 m m to 3.6 m m the tissue contents of calcium and potassium were increased dependent on [Ca]e whereas that of Na was reduced. This was due to a change in the composition of the intracellular cations as the extracellular space (inulin) and water-content of the heart muscle tissue were not influenced by incre…