Document Detail

Caffeine prolongs exercise duration in heart failure.
MedLine Citation:
PMID:  16624688     Owner:  NLM     Status:  MEDLINE    
BACKGROUND: Caffeine increases submaximal exercise performance in healthy young subjects; its effects on exercise tolerance in heart failure (HF) have not been characterized. METHODS AND RESULTS: To determine whether caffeine increases exercise tolerance in HF, caffeine (4 mg/kg intravenously, equivalent to 2 cups of coffee) or vehicle were infused into 10 treated HF patients (left ventricular ejection fraction 25 +/- 2 %), and 10 age-matched normal subjects (N) on 2 separate days in a double-blind, randomized, crossover design. We measured heart rate, blood pressure, and ventilation at rest and during graded cycling (15 W/minute) to peak effort. Peak oxygen consumption was unaffected in either group. Mean exercise time was unchanged in N (1,013 +/- 87 versus 988 +/- 107 seconds; P = .86) but was significantly increased by caffeine in HF (from 511 +/- 28 to 560 +/- 37 seconds; P = .004) despite an increase in peak minute ventilation (P < .05). Resting and peak blood pressures were higher after caffeine (P < .05) in HF, not N. CONCLUSION: Caffeine allows HF patients to exercise longer at peak effort.
Catherine F Notarius; Beverley Morris; John S Floras
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Publication Detail:
Type:  Journal Article; Randomized Controlled Trial; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of cardiac failure     Volume:  12     ISSN:  1532-8414     ISO Abbreviation:  J. Card. Fail.     Publication Date:  2006 Apr 
Date Detail:
Created Date:  2006-04-20     Completed Date:  2006-10-18     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:  220-6     Citation Subset:  IM    
Division of Cardiology and Faculty of Medicine, University Health Network and Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada.
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MeSH Terms
Caffeine / pharmacology*
Exercise Tolerance / drug effects*
Heart Failure / physiopathology*
Middle Aged
Oxygen Consumption
Time Factors
Reg. No./Substance:

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

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