Document Detail

Cardiac output-O2 uptake relation during incremental exercise in patients with previous myocardial infarction.
MedLine Citation:
PMID:  1572029     Owner:  NLM     Status:  MEDLINE    
BACKGROUND: The cardiac output-O2 uptake (VO2) relation, which is thought to be linear and predictable in normal humans, has not been clarified in cardiac patients. We evaluated the relation between cardiac output and VO2 during the incremental exercise test in patients with previous myocardial infarction. METHODS AND RESULTS: Twenty-two patients (age, 58.1 +/- 8.0 years) with previous myocardial infarction performed a symptom-limited exercise test on a cycle ergometer. VO2 was calculated from the expired gas analysis, and cardiac output was measured by a computerized cadmium telluride detector every 10 seconds during exercise. The ratio of increase in VO2 to the increase in work rate (delta VO2/delta WR) below and above the anaerobic threshold (AT) was 11.1 +/- 3.6 and 11.1 +/- 2.9 ml/min/W, respectively, showing no significant difference. However, the ratio of increase in cardiac output to increase in work rate (delta CO/delta WR) below the AT was 50.1 +/- 26.6 ml/min/W and was significantly decreased to 11.8 +/- 25.3 ml/min/W above the AT (p = 0.0002). The decreased delta CO/delta WR above the AT primarily would be due to silent myocardial ischemia produced by exercise, as there was the presence of 201Tl redistribution in 15 of 16 patients in whom myocardial 201Tl scintigraphy with dipyridamole or exercise stress testing was evaluated. delta CO/delta VO2, which has been reported to be approximately 5.5 in normal subjects, was only 4.4 +/- 2.6 at work rates below the AT and was decreased to 1.1 +/- 2.3 at work rates above the AT. CONCLUSIONS: The relation between cardiac output and VO2 during exercise in patients with previous myocardial infarction differs profoundly from that reported in normal subjects. These findings must be considered when we noninvasively estimate the change in cardiac output during exercise by obtaining VO2 in patients with coronary artery disease.
A Koike; M Hiroe; H Adachi; T Yajima; H Itoh; T Takamoto; K Taniguchi; F Marumo
Related Documents :
1822539 - Asymmetries of oxygen uptake transients at the on- and offset of heavy exercise in humans.
21907619 - High-intensity warm-ups elicit superior performance to a current soccer warm-up routine.
6882099 - The effects of amrinone on cardiac function, oxygen consumption and lactate production ...
1909689 - Smoking effect on exercise response kinetics of oxygen uptake and related variables.
11429659 - Effects of prior exercise and recovery duration on oxygen uptake kinetics during heavy ...
11072779 - Creatine supplementation alters the response to a graded cycle ergometer test.
7777709 - Factors limiting maximal o2 consumption: effects of acute changes in ventilation.
23911589 - Women candidates for diving with oxygen-enriched gas mixtures have a lower end tidal co...
15038439 - The influence of repeated arthrocentesis and exercise on matrix metalloproteinase and t...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Circulation     Volume:  85     ISSN:  0009-7322     ISO Abbreviation:  Circulation     Publication Date:  1992 May 
Date Detail:
Created Date:  1992-06-01     Completed Date:  1992-06-01     Revised Date:  2010-03-24    
Medline Journal Info:
Nlm Unique ID:  0147763     Medline TA:  Circulation     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  1713-9     Citation Subset:  AIM; IM    
Second Department of Internal Medicine, Tokyo Medical and Dental University, Japan.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Cardiac Output*
Exercise Test
Middle Aged
Myocardial Infarction / metabolism,  physiopathology*
Oxygen Consumption*
Physical Exertion*

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

Previous Document:  Lack of myocardial perfusion immediately after successful thrombolysis. A predictor of poor recovery...
Next Document:  Light chain 2 profile and activity of human ventricular myosin during dilated cardiomyopathy. Identi...