Document Detail


Correlation between refractory periods and activation-recovery intervals from electrograms: effects of rate and adrenergic interventions.
MedLine Citation:
PMID:  4064279     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Unipolar electrograms from ventricular epicardium in dogs were analyzed for the timing of local excitation and repolarization with computer assistance. The most rapid decrease in voltage in the QRS (dV/dt min) was used to determine local excitation time, and the maximum rate of voltage increase (dV/dt max) near the peak of the T wave was used to time local repolarization. The difference between dV/dt min and dV/dt max, the activation-recovery interval, is theoretically related to the net effect of the durations of the action potentials at that site. Paired data for refractory periods and activation-recovery intervals obtained from the same electrodes during fixed activation orders were obtained before and during repolarization changes induced by changes in cycle length, infusion of norepinephrine, and cardiac sympathetic nerve stimulation. Correlation coefficients were close to 1.00 and standard errors were 2.0 to 4.3 msec for changes at individual sites. Pooling of data from multiple sites increased standard errors and reduced correlation coefficients. Results provide quantification of errors in the use of unipolar electrograms to time local repolarization changes induced by variations in rate and adrenergic tone. They should increase the practical usefulness of the unipolar electrogram as a tool for assessing the time course and spatial distribution of repolarization changes.
Authors:
C K Millar; F A Kralios; R L Lux
Related Documents :
24272659 - Interaction of light and temperature on seed germination of rumex obtusifolius l.
17968099 - Texture-based feature tracking for effective time-varying data visualization.
16193269 - Perceived timing of first- and second-order changes in vision and hearing.
19862089 - Observation of light diffraction by time-resolved femtosecond correlation interferometry.
16180549 - Time's arrow in nephrology: the discovery of the kidney.
8679919 - Passive electrical properties of human stratum corneum in vitro depending on time after...
20141319 - Effect of reward probability on spatial and temporal variation.
18484829 - Time-course and surround modulation of contrast masking in human vision.
25321739 - Directive emission of red conjugated polymer embedded within zero index metamaterials.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Circulation     Volume:  72     ISSN:  0009-7322     ISO Abbreviation:  Circulation     Publication Date:  1985 Dec 
Date Detail:
Created Date:  1986-01-16     Completed Date:  1986-01-16     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  0147763     Medline TA:  Circulation     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  1372-9     Citation Subset:  AIM; IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Dogs
Electrocardiography*
Membrane Potentials
Neural Conduction* / drug effects
Norepinephrine / pharmacology*
Refractory Period, Electrophysiological* / drug effects
Regression Analysis
Time Factors
Grant Support
ID/Acronym/Agency:
HL13480/HL/NHLBI NIH HHS; HL17367/HL/NHLBI NIH HHS
Chemical
Reg. No./Substance:
51-41-2/Norepinephrine

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


Previous Document:  Treatment of canine permeability pulmonary edema: short-term effects of dobutamine, furosemide, and ...
Next Document:  Kinetics of electrophysiologic changes during oral loading of amiodarone and after withdrawal of ami...