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The Role of Flaxseed Micronutrients and Nitric Oxide (NO) in Blood Vessel and Heart Function
Published in Robert Fried, Richard M. Carlton, Flaxseed, 2023
Robert Fried, Richard M. Carlton
Just as blood vessels have an endothelial lining that participates in the function of the vessel, the heart has a parallel inner surface lining, the endocardium. The endocardium consists of a layer of endothelial cells and an underlying layer of connective tissue. Therefore, the action of the heart, just like that of arterial blood vessels, is regulated not only by action-hormones but to a great extent by the activity of NO. And, just like blood vessels, its function is jeopardized by anything that affects the viability of endothelial cells and eNO formation. Reactive oxygen species (ROS) come to mind. (2, 3)
Stroke and Transient Ischemic Attacks of the Brain and Eye
Published in Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw, Hankey's Clinical Neurology, 2020
Infective endocarditis is caused by microbial infection of the endocardial surface or of prosthetic material in the heart. More than 80% of cases are caused by Staphylococcus aureus or by species of Streptococcus or Enterococcus. The annual incidence is 3–10 cases per 100,000.
Cardiac conditions
Published in Judy Bothamley, Maureen Boyle, Medical Conditions Affecting Pregnancy and Childbirth, 2020
In order to pump effectively, the heart is a very muscular organ. The heart muscle is called the myocardium and is composed of specialised cardiac muscle which is unique to the heart. Cardiac muscle is capable of contracting without nervous stimulation. Electrical impulses spread a synchronous wave of contraction across the muscle cells that compose each chamber, producing enough force to eject blood. In pregnancy, oestrogen acts on the myocardium to increase contractility5. The inner layer of the heart is called the endocardium. This layer lines the chambers and valves of the heart. Those with cardiac diseases are vulnerable to an inflammation of the endocardium known as endocarditis and may require antibiotic prophylaxis at times of surgical intervention, including dental work and at the time of birth. The outer layer of the heart is called the pericardium and consists of two layers with a thin film of serous fluid between them.
Influence of pulsating intracardiac blood flow on radiofrequency catheter ablation outcomes in an anatomy-based atrium model
Published in International Journal of Hyperthermia, 2022
Kaihao Gu, Shengjie Yan, Xiaomei Wu
The velocity curve of PP (UMV) in one cardiac cycle at mitral annulus was based on [27], and the overall amplitude was enlarged to ensure that ① the peak flow velocity of the E-wave was less than 1.3 m/s [28]; ② the E/A wave ratio ranged from 0.75 to 1.5 [29], and ③ the mean flow velocity in LA was around 0.2 m/s [30]. The constant blood velocity at MV was calculated by averaging the UMV with respect to time. As the original atrium model had no definition of MV, an area close to the shape of the MV orifice (violet area in Figure 4) was manually designed [31]. The area was adjusted to ensure that the peak flow velocity at MV was approximately twice that at the PV inlet [27]. Saline irrigation was simulated by setting a constant velocity US of 3.45 m s−1 (corresponding to a flow rate of 15 ml min−1) on the top surface of the central lumen as an inflow [24]. The MV, as an outflow, was applied at zero pressure in this case [6,8]. In addition to the inflow and outflow of blood flow and saline irrigation, the remaining boundaries of the endocardium were applied with a non-slip condition.
Increasing clinical impact and microbiological difficulties in diagnosing coagulase-negative staphylococci in infective endocarditis – a review starting from a series of cases
Published in Current Medical Research and Opinion, 2022
Nicoleta-Monica Popa-Fotea, Alexandru Scafa-Udriste, Grigore Iulia, Alina Ioana Scarlatescu, Nicoleta Oprescu, Cosmin Mihai, Miruna Mihaela Micheu
Apart from the challenges in differentiating contamination from blood stream infection, and hence in the interpretation of blood cultures, another central and complex element in IE diagnosis is also worth mentioning: evidence of endocardial involment, either by echocardiography or other imaging techniques such as CT or PET-CT. The modified Duke criteria have less sensitivity in diagnosing prosthetic valve endocarditis and pacemaker or lead defibrillator IE, as much as 30% of these being missed by echocardiography33. This is also the case for CoNS endocarditis that tend to display very small vegetations in the early stages that are easily missed by transthoracic echocardiography or even by transoesophageal imaging. In these clinical circumstances, new cardiac explorations have had an emerging role in the form of cardiac magnetic resonance, CT, or PET-CT. In a recent study, Philip et al. show that 18 F-fluorodeoxyglucose (18 F-FDG) PET-CT reclassifies rejected or possible IE to definite IE, with a sensitivity of 83.5%34, explaining, in part, the higher sensitivity of the European Society of Cardiology (ESC) 2015 criteria that included the use of PET-CT and cardiac CT in the evaluation of endocardial involvement. Although PET-CT and CT have some limitations in terms of reproducibility, accessibility and specificity, IE has a bad prognosis and all efforts should be primarily directed on the increase in sensitivity.
Infection of cardiac prosthetic valves and implantable electronic devices: early diagnosis and treatment
Published in Acta Cardiologica, 2021
Lampros Lakkas, Burcu Dirlik Serim, Andreas Fotopoulos, Ioannis Iakovou, Argyrios Doumas, Ulku Korkmaz, Lampros K. Michalis, Chrissa Sioka
Infections related to CIED include pacemakers, cardiac defibrillators and various other cardiac resynchronisation devices. Since these devices consist of both extravascular and intravascular parts any portion of the device may be infected [8]. Thus, it may involve the implanted device pocket, cardiac parts or even bloodstream, and occurs in 0.5% to 2% of CIED implants [10]. If the endocardium is involved, the condition may be life threatening and requires immediate proper treatment [8]. Treatment should be initiated empirically, utilising an antistaphylococcal drug and continued with specific agents based on blood culture results [14]. In these cases, the endocardial portion of the device should be removed in addition to antibiotic therapy for approximately 6 weeks [9]. After effective therapy, it is acceptable to reimplant any removed cardiac devices with a generally low second infection rate, independently of the re-implant [58].