|
|
||||||||
Experimental Studies |
1 From the Department of Radiology, Division of MR Research (P.A.B.), and the Department of Medicine, Division of Cardiology (R.G.W.), Johns Hopkins University, JHOC-4221, 601 N Caroline St, Baltimore, MD 21287-0843. Received June 22, 2000; revision requested August 8; revision received September 6; accepted September 11. Supported by National Institutes of Health grants RO1 HL56882-01, HL52315-05, and HL61912-01. Address correspondence to P.A.B. (e-mail: bottoml@mri.jhu.edu).
PURPOSE: To develop image-guided spatially localized magnetic resonance (MR) spectroscopy to provide a noninvasive quantitative probe of myocardial creatine kinase (CK) metabolism, and to use it to determine the extent of changes in CK energy metabolism in nonviable infarcted canine myocardium.
MATERIALS AND METHODS: Water-referenced localized phosphorus and proton MR spectroscopy were combined in a single protocol to noninvasively measure phosphocreatine (PCr), adenosine triphosphate (ATP), and total of phosphorylated and unphosphorylated creatine (CR) concentrations and pH in the myocardium in six normal dogs and six dogs with surgically induced myocardial infarction. Unphosphorylated creatine and adenosine diphosphate (ADP) levels were calculated. The results were compared with biochemical measurements at postmortem biopsy.
RESULTS: Significant reductions in PCr-to-ATP ratios (1.7 ± 0.3 [SD] vs 1 ± 0.4; P < .001), PCr (10.3 ± 2.1 vs 4.3 ± 2.0 µmol/g wet weight; P < .0001), ATP (6.4 ± 1.4 vs 3.7 ± 1.4 µmol/g wet weight; P < .001), and CR (24.7 ± 6.1 vs 6.3 ± 3.7; P < .0001) were measured noninvasively in infarcted, as compared with normal, tissue. Biopsy measurements confirmed infarct-related reductions observed at MR spectroscopy, although high-energy phosphate concentrations were lower at biopsy. ADP calculated from noninvasive MR spectroscopic measurements was 0.11 ± 0.07 µmol/g wet weight in normal myocardium.
CONCLUSION: This combined phosphorus and proton MR spectroscopic approach provides a near-complete picture of in vivo myocardial CK metabolism in normal and diseased heart and a tool for noninvasively measuring metabolite reductions associated with the loss of viability.
Index terms: Animals Heart, MR, 511.121411, 511.121415 Heart, MR spectroscopy, 511.12145 Magnetic resonance (MR), phosphorus studies, 511.121411, 511.121415, 511.12147 Magnetic resonance (MR), spectroscopy, 511.12145 Metabolism, 511.91 Myocardium, infarction, 511.814
This article has been cited by other articles:
![]() |
J. F. A. Jansen, W. H. Backes, K. Nicolay, and M. E. Kooi 1H MR Spectroscopy of the Brain: Absolute Quantification of Metabolites. Radiology, August 1, 2006; 240(2): 318 - 332. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. C. Chen and O. Ogut Decline of contractility during ischemia-reperfusion injury: actin glutathionylation and its effect on allosteric interaction with tropomyosin Am J Physiol Cell Physiol, March 1, 2006; 290(3): C719 - C727. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. C. Wu and J. A.C. Lima Noninvasive Imaging of Myocardial Viability: Current Techniques and Future Developments Circ. Res., December 12, 2003; 93(12): 1146 - 1158. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Nakae, K. Mitsunami, T. Omura, T. Yabe, T. Tsutamoto, S. Matsuo, M. Takahashi, S. Morikawa, T. Inubushi, Y. Nakamura, et al. Proton magnetic resonance spectroscopy can detect creatine depletion associated with the progression of heart failure in cardiomyopathy J. Am. Coll. Cardiol., November 5, 2003; 42(9): 1587 - 1593. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. M. Pohost and J. R. Forder From the atomic nucleus to man: Nuclear magnetic resonance spectroscopy, the next horizon in diagnostic cardiology J. Am. Coll. Cardiol., November 5, 2003; 42(9): 1594 - 1595. [Full Text] [PDF] |
||||
![]() |
O. Ogut and F. V. Brozovich Creatine Phosphate Consumption and the Actomyosin Crossbridge Cycle in Cardiac Muscles Circ. Res., July 11, 2003; 93(1): 54 - 60. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Pucar, P. Bast, R. J. Gumina, L. Lim, C. Drahl, N. Juranic, S. Macura, E. Janssen, B. Wieringa, A. Terzic, et al. Adenylate kinase AK1 knockout heart: energetics and functional performance under ischemia-reperfusion Am J Physiol Heart Circ Physiol, August 1, 2002; 283(2): H776 - H782. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| RADIOLOGY | RADIOGRAPHICS | RSNA JOURNALS ONLINE |