Document Detail


Pulmonary hypertension and systemic hypotension as limitations to exercise in chronic heart failure.
MedLine Citation:
PMID:  9420630     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The authors have previously shown that the resistance ratio (RR) is increased in patients with congestive heart failure (CHF), and that the patients with the highest RRs have an increased mortality. The authors hypothesized that CHF patients with the lowest maximum oxygen consumption and the most impaired Weber functional classification would have the highest RR. Eighty-four patients with chronic CHF underwent seated ergometric exercise to exhaustion. Hemodynamic and respiratory gas exchange parameters were measured at rest and peak exercise. Weber functional classifications (A through E) were determined from maximum oxygen consumptions, and patients were stratified to evaluate the RR. The RR increased progressively across Weber classifications at rest (A vs E; P < .001) and with maximum exercise (A vs E; P < .002). At rest, elevation in the RR was related to an increase in the pulmonary pressure gradient (A vs E; P < .002) secondary to increased mean pulmonary arterial pressures. With peak exercise, this elevation was secondary to a decrease in the systemic pressure gradient (A vs E; P < .001). Further analysis revealed that the progressive decrease in the systemic pressure gradient was due to progressively lower mean arterial pressures (A vs E; P < .001). Elevation of the RR, both at rest and peak exercise, predicts a more impaired exercise functional status in patients with chronic CHF. Increases in the RR at peak exercise were related to decreases in mean arterial pressure, most likely limiting perfusion to exercising skeletal muscle. The mechanism of poor exercise blood pressure response in these patients is unclear. Possible explanations include abnormal systemic baroreceptor function with inappropriate vascular adaptation, and a poor cardiac output response to a relative increase in right ventricular afterload in systemic vasodilation seen with exercise.
Authors:
S W Mabee; M Metra; D E Reed; L Dei Cas; R J Cody
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Journal of cardiac failure     Volume:  1     ISSN:  1071-9164     ISO Abbreviation:  J. Card. Fail.     Publication Date:  1994 Oct 
Date Detail:
Created Date:  1998-02-02     Completed Date:  1998-02-02     Revised Date:  2007-11-15    
Medline Journal Info:
Nlm Unique ID:  9442138     Medline TA:  J Card Fail     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  27-33     Citation Subset:  IM    
Affiliation:
Division of Cardiology, Ohio State University Medical Center, Columbus 43210, USA.
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MeSH Terms
Descriptor/Qualifier:
Adult
Aged
Baroreflex / physiology
Cardiac Output
Chronic Disease
Exercise Tolerance / physiology*
Heart Failure / physiopathology*
Hemodynamics
Humans
Hypertension, Pulmonary / physiopathology*
Hypotension / physiopathology*
Middle Aged
Pulmonary Gas Exchange

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


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