Document Detail


Mechanisms of periodic breathing during exercise in patients with chronic heart failure.
MedLine Citation:
PMID:  18187746     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
BACKGROUND: Periodic breathing (PB) in heart failure (HF) is attributed to many factors, including low cardiac output delaying the time it takes pulmonary venous blood to reach the central and peripheral chemoreceptors, low lung volume, lung congestion, augmented chemoreceptor sensitivity, and the narrow difference between eupneic carbon dioxide tension and apneic/hypoventilatory threshold. METHODS AND RESULTS: We measured expired gases, ventilation, amplitude, and duration of PB in 23 patients with PB during progressive exercise tests done with 0 mL, 250 mL, or 500 mL of added dead space. Periodicity of PB remained constant despite heart rate, oxygen consumption, and minute ventilation increasing. Within each PB cycle, starting from the beginning of exercise, the largest (peak) tidal volume approached maximum observed tidal volume, while the smallest (nadir) tidal volume increased as exercise power output increased. PB ceased when nadir tidal volume reached peak tidal volume. End-tidal carbon dioxide increased with added dead space, and PB ceased progressively earlier during the exercise done with increased dead space. CONCLUSION: Circulatory delay does not contribute to the PB observed in exercising HF patients. The pattern of gradually increasing nadir tidal volume during exercise and the effect of dead space on both PB ceasing and end-tidal carbon dioxide suggest that low tidal volume and carbon dioxide apnea threshold are important contributors to PB that occurs during exercise in HF.
Authors:
Piergiuseppe Agostoni; Anna Apostolo; Richard K Albert
Related Documents :
7809566 - Ventilatory instability in patients with congestive heart failure and nocturnal cheyne-...
3840426 - An interactive software for 81mkr pulmonary ventilation gating.
9038446 - A ventilation-exchange bougie for fibreoptic intubations with the laryngeal mask airway.
8271366 - Comparison of gas exchange measurements with a mouthpiece, face mask, and ventilated ca...
24213856 - Physiological mechanisms of sex differences in exertional dyspnea: role of neural respi...
9208496 - Exercise echocardiography: feasibility and value for detection of coronary artery disease.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Chest     Volume:  133     ISSN:  0012-3692     ISO Abbreviation:  Chest     Publication Date:  2008 Jan 
Date Detail:
Created Date:  2008-01-11     Completed Date:  2008-03-06     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0231335     Medline TA:  Chest     Country:  United States    
Other Details:
Languages:  eng     Pagination:  197-203     Citation Subset:  AIM; IM    
Affiliation:
Centro Cardiologico Monzino, IRCCS, Istituto di Cardiologia, Università di Milano, Via Parea 4, 20138 Milan, Italy. piergiuseppe.agostoni@ccfm.it
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Aged
Exercise / physiology*
Female
Heart Failure / physiopathology*
Humans
Male
Respiration*
Respiratory Dead Space

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


Previous Document:  Aging dilates atrium and pulmonary veins: implications for the genesis of atrial fibrillation.
Next Document:  Is airway smooth muscle the "missing link" modulating airway inflammation in asthma?