| Effects of pericardial pressure on systemic and coronary hemodynamics in dogs. | |
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MedLine Citation:
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PMID: 7733360 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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The effects of pericardial tamponade on coronary capacitance and coronary systemic hemodynamics were calculated in two groups of animals subjected to increases in pericardial pressure (PCP) up to approximately 20 mmHg. In one group (A), flow in the left circumflex artery was measured in the intact animal under conditions of increased PCP. In the second group (B), coronary artery perfusion pressure was maintained constant with a pump while PCP was increased. In group A increased PCP was accompanied by a decrease in arterial pressure. This resulted in a marked decrease in coronary blood flow after vasodilation but without a change in coronary vascular resistance. In group B there was no change in coronary flow or coronary vascular resistance with increased PCP. Microsphere distribution to the left ventricular wall showed less endocardial than epicardial flow but no change in going from low to high PCP. Characteristic impedance was altered in the group B animals after vasodilation at medium and high PCP, indicating a loss of reflection sites and probably increased vessel tethering. The coronary artery in a subgroup of group B animals was also perfused by left ventricular pressure, the time constants for coronary backflow showing an 8-12% decrease in capacitance with low and high PCP; these values represent minimal epicardial capacitances vs. total bed capacitance. A diastolic model for the values for resistance and capacitance in the coronary bed is suggested. As expected, most of the capacitance is in the venous bed and most of the resistance is in the arterial bed. |
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Authors:
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F L Abel; L S Mihailescu; A S Lader; R G Starr |
Publication Detail:
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Type: Journal Article; Research Support, Non-U.S. Gov't |
Journal Detail:
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Title: The American journal of physiology Volume: 268 ISSN: 0002-9513 ISO Abbreviation: Am. J. Physiol. Publication Date: 1995 Apr |
Date Detail:
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Created Date: 1995-06-01 Completed Date: 1995-06-01 Revised Date: 2007-11-15 |
Medline Journal Info:
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Nlm Unique ID: 0370511 Medline TA: Am J Physiol Country: UNITED STATES |
Other Details:
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Languages: eng Pagination: H1593-605 Citation Subset: IM |
Affiliation:
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Department of Physiology, School of Medicine, University of South Carolina, Columbia 29208, USA. |
Export Citation:
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APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
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Animals Coronary Circulation Coronary Vessels / physiology* Dogs Female Fourier Analysis Hemodynamics / physiology* Male Pericardium / physiology* Pressure Time Factors Vascular Resistance Vasodilation |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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