Document Detail


Regional effects of myocardial ischemia on epicardially recorded canine first heart sounds.
MedLine Citation:
PMID:  8175520     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
To determine whether focal changes in myocardial material properties are important in determining the response of first heart sound acceleration amplitude and frequency to myocardial ischemia, cardiac vibrations were simultaneously recorded from ischemic and nonischemic regions of canine epicardium by use of ultralight acceleration transducers. Cardiac acceleration and hemodynamics were recorded before and 5 min, 15 min, 1 h, and 2 h after left circumflex coronary artery occlusion. Peak-to-peak amplitude declined transiently in the nonischemic zone during early occlusion (P < 0.05) but was not decreased at any time in the ischemic myocardium. The median frequency of first heart sound vibrations in the ischemic region increased 31% within 5 min after occlusion (P < 0.01) and remained elevated for 2 h (P < 0.05). Nonischemic zone frequency was not statistically different from baseline at any time point. The disparate regional response of first heart sound vibrational frequency to myocardial ischemia suggests that propagating mechanical transients and myocardial contractile acceleration, rather than resonant vibrations, produce the first heart sound.
Authors:
J C Wood; M P Festen; M J Lim; A J Buda; D T Barry
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Journal of applied physiology (Bethesda, Md. : 1985)     Volume:  76     ISSN:  8750-7587     ISO Abbreviation:  J. Appl. Physiol.     Publication Date:  1994 Jan 
Date Detail:
Created Date:  1994-06-06     Completed Date:  1994-06-06     Revised Date:  2007-11-15    
Medline Journal Info:
Nlm Unique ID:  8502536     Medline TA:  J Appl Physiol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  291-302     Citation Subset:  IM    
Affiliation:
Department of Internal Medicine, University of Michigan Medical School, Ann Arbor 48109.
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MeSH Terms
Descriptor/Qualifier:
Animals
Blood Pressure / physiology
Dogs
Electrocardiography
Fourier Analysis
Heart Rate / physiology
Heart Sounds / physiology*
Hemodynamics / physiology
Male
Myocardial Infarction / physiopathology
Myocardial Ischemia / physiopathology*
Phonocardiography
Signal Processing, Computer-Assisted
Grant Support
ID/Acronym/Agency:
HL-34691/HL/NHLBI NIH HHS; NS-01701/NS/NINDS NIH HHS

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


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