Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

MR spectroscopy opens a window to the non-invasive evaluation of various aspects of cardiac metabolism. Experimentally, the method has extensively been used since 1970's. 31P-MR allows the registration of cardiac high-energy phosphate metabolism to non-invasively estimate the energetic state of the heart: ATP, phosphocreatine, inorganic phosphate, monophosphate esters and intracellular pH can all be quantitated. In conjunction with extracellular shift reagents such as [DyTTHA]3- or [TmDOTP]5-, 23Na- and 39K-MR allow the measurement of intra- and extra-cellular cation pools. 1H-MR spectroscopy allows the detection of a large number of metabolites such as, e.g. creatine, lactate, or carnitine. Human cardiac spectrocsopy has so far been confined to the 31P nucleus. Localization techniques (DRESS, ISIS, 3D-CSI etc.) are required to confine the acquired signal to the heart region. Relative quantification is straightforward (phosphocreatine/ATP ratio), absolute quantification (mM) is under development. Cardiac 31P-MR spectroscopy has research application in at least three clinical areas: (1) Coronary artery disease: A biochemical stress test for non-invasive ischemia detection (decrease of phosphocreatine with exercise) and viability assessment via quantification of ATP may become feasible. (2) Heart failure: The phosphocreatine/ATP ratio may provide an independent index for grading of heart failure, allow to monitor the longterm effects of different forms of drug therapy on cardiac energy metabolism in heart failure, and may also hold prognostic information on survival. (3) Valve disease: It is possible that the decrease of phosphocreatine/ATP can be used to guide the timing for the valve replacement. At the present time, no routine clinical applications can be defined for the use of human cardiac spectroscopy in patients with cardiac disease. However, the technique holds great potential for the future as a non-invasive approach to cardiac metabolism, and in coming years routine applications may become reality.
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PMID:Clinical cardiac magnetic resonance spectroscopy--present state and future directions. 974 38

Dilated cardiomyopathy (DCM) is accompanied by an impaired cardiac energy metabolism. The aim of this study was to investigate metabolic ratios in patients with DCM compared to controls by using spectroscopic two-dimensional chemical shift imaging (2D-CSI). Twenty volunteers and 15 patients with severe symptoms (left ventricular ejection fraction, LVEF<30%) and ten patients with moderate symptoms (LVEF>30%) of DCM were investigated. Cardiac 31P MR 2D-CSI measurements (voxel size: 40x40x100 mm3) were performed with a 1.5 T whole-body scanner. Measurement time ranged from 15 min to 30 min. Peak areas and ratios of different metabolites were evaluated, including high-energy phosphates (PCr, ATP), 2,3-diphosphoglycerate (2,3-DPG) and phosphodiesters (PDE). In addition, we evaluated how PCr/ATP ratios correlate with LVEF as an established prognostic factor of heart failure. The PCr/gamma-ATP ratio was significantly decreased in patients with moderate and severe DCM and showed a linear correlation with reduced LVEFs. PDE/ATP ratios were significantly increased only in patients with severe DCM as compared to volunteers. Applying 31P MRS with commonly-available 2D-CSI sequences is a valuable technique to evaluate DCM by determining PCr/ATP ratios noninvasively. In addition to reduced PCr/ATP ratios observed in patients suffering from DCM, significantly-increased PDE/ATP ratios were found in patients with severe DCM.
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PMID:Noninvasive measurements of cardiac high-energy phosphate metabolites in dilated cardiomyopathy by using 31P spectroscopic chemical shift imaging. 1563 May 72