We have located links that may give you full text access.
Respiratory muscles performance is related to oxygen kinetics during maximal exercise and early recovery in patients with congestive heart failure.
Circulation 1999 August 4
BACKGROUND: Dyspnea and fatigue are the main causes of exercise limitation in chronic heart failure (CHF) patients, whose peak inspiratory (Pi(max)) and expiratory pressures (Pe(max)) are often reduced. The aim of this study was to examine the relationship between respiratory muscle performance and oxygen kinetics.
METHODS AND RESULTS: A total of 55 patients (NYHA class I to III) and 11 healthy subjects underwent cardiopulmonary exercise tests (CPET) on a treadmill. In 45 of the 55 patients (group I) and in healthy subjects (group II), pulmonary function tests, Pi(max), and Pe(max) were measured before and 10 minutes after exercise, and oxygen kinetics were monitored throughout and during early recovery from CPET. The first degree slope of oxygen consumption (VO(2)) decline during early recovery (VO(2)/t-slope) and VO(2) half-time (T(1/2)) were calculated. In 10 of the 55 CHF patients (group III), the measurements of Pi(max) were repeated 2, 5, and 10 minutes after CPET. A >10% reduction in Pi(max) after CPET (subgroup IA) was measured in 11 of 45 patients. In contrast, 34 of 45 CHF patients (subgroup IB) and all control subjects (group II) had Pi(max)>90% of baseline value after CPET. Subgroup IA patients had significantly lower peak VO(2) (13.5+/-2.1 versus 17.8+/-5.6 mL. kg(-1). min(-1); P<0.001), lower anaerobic thresholds (10.1+/-2.4 versus 13.6+/-4.6 mL. kg(-1). min(-1); P=0.003) and lower VO(2)/t-slopes (0.365+/-0.126 versus 0.519+/-0.227 L. min(-1). min(-1); P=0.008) than subgroup IB patients.
CONCLUSIONS: The reduction of Pi(max) after exercise is associated with prolonged early recovery of oxygen kinetics, which may explain, in part, the role played by respiratory muscles in exercise intolerance in CHF patients.
METHODS AND RESULTS: A total of 55 patients (NYHA class I to III) and 11 healthy subjects underwent cardiopulmonary exercise tests (CPET) on a treadmill. In 45 of the 55 patients (group I) and in healthy subjects (group II), pulmonary function tests, Pi(max), and Pe(max) were measured before and 10 minutes after exercise, and oxygen kinetics were monitored throughout and during early recovery from CPET. The first degree slope of oxygen consumption (VO(2)) decline during early recovery (VO(2)/t-slope) and VO(2) half-time (T(1/2)) were calculated. In 10 of the 55 CHF patients (group III), the measurements of Pi(max) were repeated 2, 5, and 10 minutes after CPET. A >10% reduction in Pi(max) after CPET (subgroup IA) was measured in 11 of 45 patients. In contrast, 34 of 45 CHF patients (subgroup IB) and all control subjects (group II) had Pi(max)>90% of baseline value after CPET. Subgroup IA patients had significantly lower peak VO(2) (13.5+/-2.1 versus 17.8+/-5.6 mL. kg(-1). min(-1); P<0.001), lower anaerobic thresholds (10.1+/-2.4 versus 13.6+/-4.6 mL. kg(-1). min(-1); P=0.003) and lower VO(2)/t-slopes (0.365+/-0.126 versus 0.519+/-0.227 L. min(-1). min(-1); P=0.008) than subgroup IB patients.
CONCLUSIONS: The reduction of Pi(max) after exercise is associated with prolonged early recovery of oxygen kinetics, which may explain, in part, the role played by respiratory muscles in exercise intolerance in CHF patients.
Full text links
Related Resources
Trending Papers
Heart failure with preserved ejection fraction: diagnosis, risk assessment, and treatment.Clinical Research in Cardiology : Official Journal of the German Cardiac Society 2024 April 12
Proximal versus distal diuretics in congestive heart failure.Nephrology, Dialysis, Transplantation 2024 Februrary 30
Efficacy and safety of pharmacotherapy in chronic insomnia: A review of clinical guidelines and case reports.Mental Health Clinician 2023 October
World Health Organization and International Consensus Classification of eosinophilic disorders: 2024 update on diagnosis, risk stratification, and management.American Journal of Hematology 2024 March 30
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app