Document Detail

Exercise-induced QRS changes in healthy men and women: a multivariate analysis on their relation to background data and exercise performance.
MedLine Citation:
PMID:  1396802     Owner:  NLM     Status:  MEDLINE    
Changes in the QRS segment during exercise have repeatedly been suggested to provide diagnostic information with respect to ischaemic heart disease, but the subject is controversial. In order to study the possibly confounding effects of gender, age, resting ECG and exercise performance, 50 healthy subjects were investigated with computerized vectorcardiography during a maximal ergometer exercise test. The overall change in the QRS complex decreased significantly with age and female gender (P < 0.001). However, these responses were better explained by baseline QRS size, change in heart rate and systolic blood pressure (adjusted r2 > 0.70, vs adjusted r2 > 0.41). Effects of age were seen in the Y-lead, and gender effects in the X- and Z-leads (P < 0.0001). In multivariate analyses, X- and Y-lead alterations correlated negatively to change in heart rate and resting QRS size (X-lead; adjusted r2 > 0.50, Y-lead; r2 > 0.44). Z-lead alterations correlated negatively with female gender and resting Z-lead QRS size (adjusted r2 > 0.31). ST changes correlated with QRS changes in the X- and Y-leads (P < 0.05). QRS changes immediately after exercise correlated with alterations during exercise (P < 0.004), maximal load (P < 0.01) and time to hypotension post-exercise (X- and Z-lead; P < 0.02). In conclusion, QRS changes appear to be related to baseline QRS size, change in heart rate and ST change, factors which may have important confounding effects. Consideration of these factors may help in resolving the controversy surrounding QRS changes.
M Pilhall; M Riha; S Jern
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  European heart journal     Volume:  13     ISSN:  0195-668X     ISO Abbreviation:  Eur. Heart J.     Publication Date:  1992 Oct 
Date Detail:
Created Date:  1992-11-17     Completed Date:  1992-11-17     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  8006263     Medline TA:  Eur Heart J     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  1316-24     Citation Subset:  IM    
Department of Clinical Physiology, Ostra Hospital, University of Gothenberg, Sweden.
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MeSH Terms
Age Factors
Exercise / physiology*
Exercise Test
Heart Rate
Multivariate Analysis
Reference Values
Regression Analysis
Sex Factors
Signal Processing, Computer-Assisted

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

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