Article Abstract:
The effects of myocardial ischemia (insufficient oxygen supply to heart muscle) include important metabolic changes in heart muscle cells, yet these remain largely uncharacterized. Research usually focuses instead on the anatomical and functional consequences of these metabolic alterations. To learn more about cellular energy utilization in the heart, studies were performed of normal subjects (11 people); patients with coronary heart disease and ischemia (16); patients with nonischemic heart disease (valve disorders or disease of the heart muscle, 9); and five patients from the ischemia group studied again after angioplasty (a method of restoring a blocked or narrowed vessel to patency) or coronary-artery bypass grafting (revascularization). Spatially localized phosphorus-31 nuclear magnetic resonance (31P NMR) spectra were analyzed to ''track'' radioactively labeled phosphorus through the biochemical pathways that represent energy utilization. Subjects were evaluated before, during and after isometric exercise using a hand-grip dynamometer. The phosphocreatine/ATP ratio (a measure of energy storage; a high ratio indicates a high reserve) did not change in normal subjects or those with nonischemic heart disease upon exercise, but it declined in people with coronary artery disease while they exercised. The ratio for patients after revascularization remained constant during exercise. The results indicate that spatially localized 31P NMR spectroscopy can be used to evaluate myocardial ischemia in patients with coronary artery disease who perform isometric stress tests. The method is noninvasive and may also be useful for assessing the effects of treatments for ischemia. (Consumer Summary produced by Reliance Medical Information, Inc.)
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Article Abstract:
Research indicates that atherosclerosis may have an inflammatory component. Heart disease continues to be a major cause of death despite lifestyle changes and the use of drugs that lower blood cholesterol levels. Up to half of all patients with cardiovascular disease do not have elevated cholesterol levels. Many fatty plaques in arteries contain immune cells as well as fat. This indicates that atherosclerosis is an inflammation. Infection with some viruses has also been linked to atherosclerosis and the viruses have been isolated from fatty plaques.
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Article Abstract:
Research has shown that coronary artery disease may have an inflammatory component. Inflammatory proteins are produced by the liver, immune cells, and blood vessels.
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