Document Detail


Systolic coronary flow reduction in the canine heart in situ: effects of left ventricular pressure and elastance.
MedLine Citation:
PMID:  8996632     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
In the externally perfused coronary bed of the isolated heart, LV elastance (Elv) rather than LV pressure (Plv) appears to be the major factor responsible for systolic coronary flow reduction, although effects of both have been demonstrated. However, normal perfusion in the presence of intact autoregulation in the heart in situ may modify these effects. To investigate the systolic coronary flow (Qsyst) responses to changes in end-systolic Elv and in systolic Plv in the intact coronary bed, we studied 7 anesthetized dogs. Dogs were vagotomized, paced and instrumented with Doppler flow probes. Elv, obtained from micromanometer- and conductance-catheters, was changed by dobutamine infusion (10 micrograms/kg/min) and characterized by its slope (Ees) and volume position at 15 kPa (V15). Plv was changed stepwise by volume loading. Correction for metabolism induced changes in Qmean was made. Thus, we found that dobutamine increased Ees by 44% (p < 0.0001), decreased V15 by 43% (p < 0.0001), and reduced corrected Qsyst significantly (p < 0.001) from 22.8 to 13.8 ml/min, while Plv (9.5-19.5 kPa) did not affect corrected Qsyst (p > 0.5). We conclude that systolic coronary flow reduction is related to both elastance parameters, Ees and V15, and not to Plv in the normally perfused canine heart in situ.
Authors:
J Baan; P Steendijk; A Mikuniya; J Baan
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Basic research in cardiology     Volume:  91     ISSN:  0300-8428     ISO Abbreviation:  Basic Res. Cardiol.     Publication Date:    1996 Nov-Dec
Date Detail:
Created Date:  1997-03-28     Completed Date:  1997-03-28     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0360342     Medline TA:  Basic Res Cardiol     Country:  GERMANY    
Other Details:
Languages:  eng     Pagination:  468-78     Citation Subset:  IM    
Affiliation:
Department of Cardiology, University Hospital of Leiden, The Netherlands.
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MeSH Terms
Descriptor/Qualifier:
Animals
Blood Flow Velocity
Cardiotonic Agents / pharmacology
Coronary Vessels / drug effects,  physiology*
Dobutamine / pharmacology
Dogs
Elastic Tissue / physiology*
Heart / drug effects,  physiology*
Heart Rate
Laser-Doppler Flowmetry
Perfusion
Systole / drug effects,  physiology*
Ventricular Function, Left / physiology*
Ventricular Pressure / drug effects,  physiology*
Chemical
Reg. No./Substance:
0/Cardiotonic Agents; 34368-04-2/Dobutamine

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


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