Journal ArticleDOI
Spectroscopic imaging and spatial localization using adiabatic pulses and applications to detect transmural metabolite distribution in the canine heart.
P.-M. Robitaille,Hellmut Merkle,E. Sublett,Kristy Hendrich,Brian T. Lew,G. Path,Arthur H. L. From,Robert J. Bache,Michael Garwood,Kamil Ugurbil +9 more
TLDR
Results demonstrate that one‐dimensional techniques are adequate for transmural detection of metabolites provided signal origin is restricted to a column perpendicular to the left ventricle wall, and a new method of spatial localization is introduced.Abstract:
Adiabatic pulses have been employed in spectroscopic imaging and relaxation rate measurements at 4.7 T to demonstrate the feasibility of obtaining spectroscopic data from the complete sensitive volume of a surface coil using the surface coil as a transmitter and receiver. With conventional B1 sensitive pulses, spectroscopic localization or imaging techniques, such as chemical-shift imaging, yield resonance intensities that are distorted severely as a function of space, and maximal signal is detected from a small region within the complete sensitive volume of the coil. With adiabatic pulses, however, this problem is eliminated completely. In addition, a new method of spatial localization is introduced. This method, referred to as FLAX-ISIS, is a derivative of longitudinally modulated Fourier series window and ISIS approaches and utilizes adiabatic inversion and excitation pulses. The method allows construction of localized spectra for multiple regions along the surface coil axis by postacquisition data manipulation of a single set of free induction decays. These techniques were applied to the study of the myocardium using an implanted surface coil in an instrumented closed-chest canine model and in an open-chest preparation. The results demonstrate that one-dimensional techniques are adequate for transmural detection of metabolites provided signal origin is restricted to a column perpendicular to the left ventricle wall.read more
Citations
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Journal ArticleDOI
Bioenergetic abnormalities associated with severe left ventricular hypertrophy.
Jianyi Zhang,Hellmut Merkle,Kristy Hendrich,Michael Garwood,Arthur H. L. From,Kamil Ugurbil,Robert J. Bache +6 more
TL;DR: High energy phosphate levels and the CP/ATP ratio are significantly decreased in severe LVH, demonstrating that abnormalities are proportional to the degree of hypertrophy but are not the result of persistent abnormalities of myocardial perfusion.
Journal ArticleDOI
High-energy phosphate metabolism and creatine kinase in failing hearts: a new porcine model.
TL;DR: In this new model of heart failure/hypertrophy, the abnormal myocardial HEP metabolism isrelated to the decreased CK-Mt protein level, which in turn is related to the severity of the hypertrophy.
Journal ArticleDOI
Phosphate metabolite concentrations and ATP hydrolysis potential in normal and ischaemic hearts
TL;DR: It is hypothesized that inorganic phosphate is both the primary feedback signal for stimulating oxidative phosphorylation in vivo and also the most significant product of ATP hydrolysis in limiting the capacity of the heart to hydrolyse ATP in vivo.
Book ChapterDOI
In vivo NMR spectroscopy.
TL;DR: In vivo nuclear magnetic resonance (NMR) spectroscopy has an assured role to play in medical research because it enables one to interrogate non-invasively a range of biochemical processes, both in the resting state and then serially when they are changing in response to some induced stress.
References
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