Search results for "Heart"
showing 10 items of 3201 documents
Analgesic and physiological effects in conscious sedation with different nitrous oxide concentrations
2015
Objectives: to study the physiological changes, as well as the psychosedative and analgesic effects of nitrous oxide, in experimental conditions. Study Design: 101 dental students volunteers participated in a single nitrous oxide sedation session without dental treatment. Signs and symptoms were registered during and after the procedure. Pulse rate and hemoglobin oxygen saturation were monitored at: 100 per cent O 2 , 30 per cent N 2 O, 50 per cent N 2 O and 5 minutes after 100 per cent O 2 . A Likert scale was used to evaluate pain perception. The analgesic effects of nitrous oxide were evaluated at: 30 per cent N 2 O, 50 per cent N 2 O, and five minutes postoperatively. Results: Pulse rat…
Tetralogy of Fallot as a Model to Study Cardiac Progenitor Cell Migration and Differentiation During Heart Development
2009
Tetralogy of Fallot (ToF) has long been considered a congenital disorder that occurs due to environmental alterations during gestation. Recently, several mutated genes have been discovered that are thought to be responsible for the malformations observed in ToF. These genetic mutations, which are microdeletions, are sporadic and are frequently also present in trisomy 21 patients. The ToF malformations can be lethal, but for the last 50 years, surgical repairs that place an artificial patch to repair the four features of ToF have improved the survival of patients with ToF. However, 0.5% to 6% of patients who survive after surgical repair of ToF die of sudden cardiac death caused by ventricul…
Bisphosphonates and atherosclerosis: why?
2005
The increasing knowledge on bone calcification processes has revealed some similarities with vascular tissue, where calcifications of arteries and cardiac valves contribute to several cardiovascular problems, such as heart failure, systolic hypertension, and myocardial and peripheral ischemic disease. Bisphosphonates have been used extensively for over two decades for the treatment of diseases associated with excessive bone resorption, i.e., osteoporosis, osteolytic bone metastasis, hypercalcemia and Paget’s disease, by blocking osteoclastic function. Etidronate, pamidronate and clodronate has been shown to inhibit the development of experimental atherosclerosis, and proposed mechanisms fo…
Early Effects of Sacubitril/Valsartan on Exercise Tolerance in Patients with Heart Failure with Reduced Ejection Fraction.
2019
Background. Sacubitril/valsartan in heart failure (HF) with reduced ejection fraction (HFrEF) was shown to be superior to enalapril in reducing the risk of death and hospitalization for HF. Our aim was to evaluate the cardiopulmonary effects of sacubitril/valsartan in patients with HFrEF. Methods. We conducted an observational study. Ninety-nine ambulatory patients with HFrEF underwent serial cardiopulmonary exercise tests (CPET) after initiation of sacubitril/valsartan in addition to recommended therapy. Results. At baseline, 37% of patients had New York Heart Association (NYHA) class III. After a median follow-up of 6.2 months (range 3&ndash
Focus on right ventricular outflow tract septal pacing
2013
SummaryExperimental and clinical studies have shown that right ventricular apical pacing may result in long-term deleterious effects on account of its negative impact on left ventricular remodeling through desynchronization. This risk appears more pronounced in patients with even moderate left ventricular dysfunction and generally occurs after at least 1 year of pacing. As right ventricular apical pacing may be associated with the development of organic mitral insufficiency, other sites that allow for more physiological stimulation, such as right ventricular outflow tract septal pacing, have been developed, with good feasibility and reproducibility. However, the prospective randomized studi…
Atherosclerosis, inflammation and Chlamydia pneumoniae
2009
Coronary heart disease is the single most common cause of illness and death in the developed world. Coronary atherosclerosis is by far the most frequent cause of ischemic heart disease, and plaque disruption with superimposed thrombosis is the main cause of the acute coronary syndromes of unstable angina, myocardial infarction, and sudden death. Atherosclerosis is the result of a complex interaction between blood elements, disturbed flow, and vessel wall abnormality, involving several pathological processes: inflammation, with increased endothelial permeability, endothelial activation, and monocyte recruitment; growth, with smooth muscle cell proliferation, migration, and matrix synthesis; …
Influence of genetic polymorphisms and mutations in the cardiac pathology of iron overload in thalassemia and sickle cell anemia patients: a retrospe…
2012
Cardiac disease in thalassemia is determined by the accumulation of iron in the tissue. Genetic factors could influence the severity and the rapidity of the modifications of the cardiac tissue. Mutations or polymorphisms of genes have already been described as being implicated in cardiac disease. In particular, we studied the polymorphisms C1091T in the Connexin 37 gene (CX 37), 4G -668 5G in the Plasminogen Activator Inhibitor-1 gene (PAI 1) and 5A-1171 6A in the Stromelysin-1 gene (SL) in 193 randomly selected patients affected by hemoglobinopathies and 100 normal subjects randomly selected from the general population. A retrospective analysis based on history, clinical data and imaging s…
Heart failure and anti tumor necrosis factor-alpha in systemic chronic inflammatory diseases.
2013
Tumor necrosis factor alpha (TNF-alpha) antagonists have emerged as an effective therapy for patients with diseases as Crohn's disease, rheumatoid arthritis, and other chronic systemic inflammatory diseases. In the last years, there has been a growing interest in the role that inflammatory cytokines, which sustain the pathogenesis of these diseases, plays in regulating cardiac structure and function, particularly in the progression of chronic heart failure. In fact there is an increase of anti-TNF alpha levels in advanced heart failure but the treatment with anti-TNF alpha has been shown to worsen the prognosis of heart failure in randomized controlled trials. Patients with rheumatoid arthr…
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…
From Clinical Imaging to Patient-Specific Computational Model: Rapid Adaptation of the Living Heart Human Model to a Case of Aortic Stenosis
2021
Aortic stenosis (AS) is the most common acquired heart valve disease in the developed world. Traditional methods of grading AS have relied on the measurement of aortic valve area and transvalvular pressure gradient. Recent research has highlighted the existence of AS variants that do not meet classic criteria for severe AS such as low-flow, low-gradient AS. With the development of sophisticated multi-scale computational models, investigation into the left ventricular (LV) biomechanics of AS offers new insights into the pathophysiology that may guide treatment decisions surrounding AS. Building upon our prior study entailing LV-aortic coupling where AS conditions were applied to the idealize…