Document Detail


First-pass dynamic contrast-enhanced MRI with extravasating contrast reagent: evidence for human myocardial capillary recruitment in adenosine-induced hyperemia.
MedLine Citation:
PMID:  18727151     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Human myocardial (1)H(2)O T(1)-weighted dynamic contrast-enhanced MRI data were acquired during the brief first-pass period after injection of a very small gadolinium diethylenetriaminepenta-acetate (GdDTPA(2-)) dose. The shutter-speed pharmacokinetic effects of both transendothelial and transcytolemmal equilibrium water exchange processes were investigated. Our results indicate that even for such a short acquisition window and relatively large pseudo-first-order rate constant (K(trans)) for plasma/interstitium contrast reagent (CR) transfer the kinetics of these water exchange processes cannot be treated as infinitely fast or slow. However, neither the intracellular water molecule lifetime (tau(i)) nor its intravascular counterpart (tau(b)) are among the parameters most influential in analysis of the noisy data typically associated with the cardiac perfusion application. Thus, the actual values of water exchange kinetic rate constants are relatively indeterminate as this experiment is usually conducted. Combining the K(trans) evaluations with independently determined flow (F) values allows us to estimate CR permeability coefficient surface area product (P(CR)S) values. The fact that the P(CR)S magnitudes almost equal the K(trans) values confirms that GdDTPA(2-) extravasation in resting human myocardial muscle is indeed permeation-limited and supports the validity of the K(trans) and P(CR)S estimations. Nevertheless the model analysis is most consistent with the results if P(CR)S is not assumed to be constant with changing flow. The capillary blood volume fraction (v(b)) is a sensitive parameter in the analysis. We also compared resting and hyperemic cardiac conditions, the latter resulting from the volume flow increase induced by adenosine arteriolar vasodilation. We found that the P(CR)S value increases with flow probably mostly because of an S increase associated with capillary recruitment. The v(b) values also increased in hyperemia and showed a flow-dependence with a clearly identifiable component due to capillary recruitment.
Authors:
Xin Li; Charles S Springer; Michael Jerosch-Herold
Publication Detail:
Type:  Journal Article; Randomized Controlled Trial; Research Support, N.I.H., Extramural    
Journal Detail:
Title:  NMR in biomedicine     Volume:  22     ISSN:  0952-3480     ISO Abbreviation:  NMR Biomed     Publication Date:  2009 Feb 
Date Detail:
Created Date:  2009-02-09     Completed Date:  2009-04-16     Revised Date:  2011-01-17    
Medline Journal Info:
Nlm Unique ID:  8915233     Medline TA:  NMR Biomed     Country:  England    
Other Details:
Languages:  eng     Pagination:  148-57     Citation Subset:  IM    
Copyright Information:
Copyright (c) 2008 John Wiley & Sons, Ltd.
Affiliation:
Advanced Imaging Research Center, Oregon Health & Science University, Portland, OR 97239, USA. lxin@ohsu.edu
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adenosine / diagnostic use*
Aged
Aged, 80 and over
Capillary Permeability*
Computer Simulation
Contrast Media / pharmacokinetics
Extravasation of Diagnostic and Therapeutic Materials / diagnosis*,  metabolism*
Female
Gadolinium DTPA / diagnostic use*,  pharmacokinetics*
Heart / anatomy & histology
Humans
Hyperemia / diagnosis*
Image Interpretation, Computer-Assisted / methods
Male
Middle Aged
Models, Cardiovascular
Myocardium / metabolism*
Reproducibility of Results
Sensitivity and Specificity
Grant Support
ID/Acronym/Agency:
R01 EB000422-19/EB/NIBIB NIH HHS; R01 EB000422-20/EB/NIBIB NIH HHS; R01 EB000422-21/EB/NIBIB NIH HHS; R01 EB000422-22/EB/NIBIB NIH HHS; R01 EB000422-23/EB/NIBIB NIH HHS; R01 EB000422-24/EB/NIBIB NIH HHS; R01 NS040801-01/NS/NINDS NIH HHS; R01 NS040801-02/NS/NINDS NIH HHS; R01 NS040801-03/NS/NINDS NIH HHS; R01 NS040801-04/NS/NINDS NIH HHS; R01 NS040801-05/NS/NINDS NIH HHS; R01 NS040801-06A1/NS/NINDS NIH HHS; R01-EB00422/EB/NIBIB NIH HHS; R01-HL65580/HL/NHLBI NIH HHS; R01-NS40801/NS/NINDS NIH HHS
Chemical
Reg. No./Substance:
0/Contrast Media; 58-61-7/Adenosine; 80529-93-7/Gadolinium DTPA

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Effect of age and food intake on dietary carbon turnover recorded in sheep wool.
Next Document:  The gap-filling sequence on the left arm of chromosome 2 in fission yeast Schizosaccharomyces pombe.