Ventilation carbon dioxide production ratio in early exercise predicts poor functional capacity in congestive heart failure

Milani, R. V., Mehra, M. R., Reddy, T. K., Lavie, C. J. and Ventura, H. O. (1996) Ventilation carbon dioxide production ratio in early exercise predicts poor functional capacity in congestive heart failure. Heart, 76 5: 393-396. doi:10.1136/hrt.76.5.393


Author Milani, R. V.
Mehra, M. R.
Reddy, T. K.
Lavie, C. J.
Ventura, H. O.
Title Ventilation carbon dioxide production ratio in early exercise predicts poor functional capacity in congestive heart failure
Journal name Heart   Check publisher's open access policy
ISSN 1355-6037
1468-201X
Publication date 1996-11
Sub-type Article (original research)
DOI 10.1136/hrt.76.5.393
Volume 76
Issue 5
Start page 393
End page 396
Total pages 4
Place of publication London, United Kingdom
Publisher BMJ
Language eng
Formatted abstract
Abstract Objectives: To evaluate whether changes in the ventilation/carbon dioxide production ratio during early exercise could reliably serve as a surrogate marker for maximal oxygen consumption in heart failure patients. Maximal oxygen consumption is an important determinant of the severity of congestive heart failure with values >14 ml/kg/min conferring a good 2-year survival. However, many patients undergoing cardiopulmonary exercise testing cannot exercise maximally because of other functional limitations.

Methods: Ventilation/carbon dioxide production ratio was assessed at rest, anaerobic threshold, and peak exercise in 75 patients with chronic heart failure and in 12 healthy controls. Patients were divided into two groups on the basis of heart failure severity as judged by maximal oxygen consumption.

Results: Patients with mild-moderate heart failure had a 20% reduction in the ventilation/carbon dioxide production ratio at anaerobic threshold similar to that in healthy controls. Patients with severe heart failure failed to reduce this ratio at anaerobic threshold. Furthermore, a reduction in the ventilation/carbon dioxide production ratio in early exercise of less than 10% predicted a maximal oxygen consumption of <14 ml/kg/min with a positive predictive value of 96% and a negative predictive value of 88%.

Conclusions: A reduction of the ventilation/carbon dioxide production ratio of less then 10% with early exercise reliably predicts poor functional capacity in congestive heart failure. Changes in this ratio during early exercise may be used as a surrogate for maximal oxygen consumption in patients who cannot exercise maximally.
Keyword Heart failure
Oxygen uptake
Exercise tolerance
Carbon dioxide output
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Non-UQ

Document type: Journal Article
Sub-type: Article (original research)
Collection: School of Medicine Publications
 
Versions
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 19 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 0 times in Scopus Article
Google Scholar Search Google Scholar
Created: Mon, 14 Mar 2011, 09:36:51 EST