Document Detail


Radiopharmaceuticals for studying cardiac metabolism.
MedLine Citation:
PMID:  2155188     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
(1) Metabolism is the link between myocardial blood flow and physiological performance of the heart. (2) Metabolic myocardial radiopharmaceuticals have the potential to identify metabolic alterations unique to a given intrinsic cardiac disease (e.g. cardiomyopathies), to assess acute metabolic changes or in delineating a specific chronic metabolic defect (e.g. coronary artery disease). (3) Two approaches can be employed to evaluate in vivo myocardial utilization of subtracts: (a) use of radiolabeled "physiologic" substrates e.g. positron emitting 11C-palmitic acid was successfully employed for assessing the in vivo metabolic sequelae of myocardial ischemia, infarction and cardiomyopathies, and (b) use of modified tracers which enter known metabolic pathways. However, because of their unique structure, metabolism of the tracer stops at a certain state thus leaving the radiolabel trapped in the cell, e.g. [18F]FDG for measuring glucose metabolic rate in the human brain and myocardium. (4) Among the radiopharmaceuticals for planar and single photon tomography, the para and the ortho isomers of 123I-phenyl iodoheptadecanoic acids and their beta-methyl derivatives are the most promising tracers for myocardial metabolic studies. (5) Ortho-(123I-phenyl)-pentadecanoic acid (o-IPPA) human myocardial uptake was rapidly and markedly elevated in well perfused segments; myocardial turnover was strikingly prolonged, suggesting some "trapping" phenomenon, resulting in excellent scintigrams. This is in contrast to the relatively shorter clearance of the para isomer from the myocardium. (6) 11C-Palmitic acid and [18F]FDG are the most widely used for PET scanning for following myocardial metabolism. The most important clinical application of these agents is predicting viability of ischemic myocardium. (7) A significant proportion of fixed perfusion defects seen on thallium studies can be demonstrated to be viable myocardium on PET scans using metabolic agents. If the markers of perfusion alone are relied on to assess tissue viability, the extent of salvageable myocardium may be underestimated. The demonstration of myocardial viability is crucial in the decision of the optimal treatment of the disease.
Authors:
M A Antar
Related Documents :
6608548 - Quantitative analysis of seven-pinhole tomographic thallium-201 scintigrams: improved s...
7081048 - Clinical implications of increased lung uptake of thallium-201 during exercise scintigr...
18071698 - Estimate of myocardial salvage in late presentation acute myocardial infarction by comp...
7741228 - Thallium-201 as an agent for myocardial imaging studies.
1130888 - Resection of the ascending aorta using profound local hypothermia for myocardial protec...
19041328 - Cardiac myofibroblast differentiation is attenuated by alpha(3) integrin blockade: pote...
Publication Detail:
Type:  Journal Article; Review    
Journal Detail:
Title:  International journal of radiation applications and instrumentation. Part B, Nuclear medicine and biology     Volume:  17     ISSN:  0883-2897     ISO Abbreviation:  Int J Rad Appl Instrum B     Publication Date:  1990  
Date Detail:
Created Date:  1990-04-12     Completed Date:  1990-04-12     Revised Date:  2008-02-21    
Medline Journal Info:
Nlm Unique ID:  8611098     Medline TA:  Int J Rad Appl Instrum B     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  103-28     Citation Subset:  IM    
Affiliation:
Department of Nuclear Medicine, University of Connecticut Health Center, Farmington 06032.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Fatty Acids / diagnostic use,  metabolism
Humans
Myocardium / metabolism*
Radioisotopes / diagnostic use*
Receptors, Adrenergic, beta / metabolism
Receptors, Muscarinic / metabolism
Tomography, Emission-Computed
Tomography, Emission-Computed, Single-Photon
Chemical
Reg. No./Substance:
0/Fatty Acids; 0/Radioisotopes; 0/Receptors, Adrenergic, beta; 0/Receptors, Muscarinic

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


Previous Document:  Dissimilarities in superoxide anion production by human neutrophils stimulated by phorbol myristate ...
Next Document:  Coliform septicemia and pulmonary disease associated with canine parvoviral enteritis: 88 cases (198...