Document Detail


Myocardial blood flow regulation relative to left ventricle pressure and volume in anesthetized dogs.
MedLine Citation:
PMID:  10593664     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The influence of left ventricle pressure and volume changes on coronary blood flow was investigated in eight anesthetized dogs. Coronary artery pressure-flow relationships were determined at two levels of left ventricular pressure and volume. The distribution of blood flow within the myocardium was also determined when these relationships varied. Reducing left ventricle pressures and volumes increased heart rate. Rate-pressure product, diastolic coronary pressure, myocardial O2 consumption, total, subendocardial and subepicardial flow decreased. Hematocrit and blood gas data were unchanged. The pressure-flow relationships were shifted leftward (p = 0.001) but the range of autoregulation was not altered. At low left ventricle pressures and volumes, the lower coronary artery pressure limit was shifted leftward (from 75 to 45 mm Hg (1 mm Hg = 133.3 Pa)), while total, subendocardial, and subepicardial blood flow did not change compared with the control. Below the lower coronary artery pressure limit, subendocardial but not subepicardial flow decreased, resulting in maldistribution of flow across the left ventricular wall. When coronary pressure was reset between control and the lower coronary artery pressure limit, subendocardial flow was restored. These results show that the lower coronary artery pressure limit can be shifted leftward while the distribution of blood flow across the left ventricular wall is preserved.
Authors:
J R Rouleau; D Simard; J G Kingma
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Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Canadian journal of physiology and pharmacology     Volume:  77     ISSN:  0008-4212     ISO Abbreviation:  Can. J. Physiol. Pharmacol.     Publication Date:  1999 Nov 
Date Detail:
Created Date:  1999-12-30     Completed Date:  1999-12-30     Revised Date:  2007-11-15    
Medline Journal Info:
Nlm Unique ID:  0372712     Medline TA:  Can J Physiol Pharmacol     Country:  CANADA    
Other Details:
Languages:  eng     Pagination:  902-8     Citation Subset:  IM    
Affiliation:
Université Laval and Quebec Heart Institute, Department of Cardiology, Laval Hospital, Ste-Foy, Canada. jacques-r.rouleau@med.ulaval.ca
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MeSH Terms
Descriptor/Qualifier:
Anesthesia
Animals
Blood Gas Analysis
Cardiac Volume / physiology*
Coronary Circulation / physiology*
Dogs
Hematocrit
Hemodynamics / physiology
Homeostasis / physiology*
Male
Myocardium / metabolism
Oxygen Consumption
Respiration, Artificial
Ventricular Function, Left / physiology*
Ventricular Pressure / physiology*

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


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