Effects of age and exercise training on ventilatory efficiancy in chronic heart failure

Abstract

Background: Parameters of ventilatory efficiency like the VE/VCO2slope and the Oxygen Uptake Efficiancy Slope (OUES) have recently been shown to be of high prognostic value in patients with advanced chronic heart failure. However, there is a paucity of data, whether those parameters can be positively altered by established interventions in CHF like exercise training and if potential beneficial training effects are diminished in older patients. Method(s): 60 CHF patients and 60 age-matched referent controls were randomized to 4 weeks of bicycle ergometer training at 70% of the heart rate reserve 4 x 20 min/day or to a control group (C). Before and after the intervention a cardiopulmonary exercise test was performed and parameters of ventilatory efficiency were calculated. Result(s): Training Effects: In younger CHF patients (n= 15, age 45+/-3 years, BMI 26.8+/-2.7, LV-EF 26.8+/-2.6%) training improved the VE/ VCO2slope from 41.3+/-3.6 to 35.1+/-3.2 (p=0.004 vs. control) and the OUES from 1472+/-287 to 1783+/-196 (p = 0.003 vs. control). In elderly CHF patients (n=15, age 68+/-4 years, BMI 25.3+/-2.9, LV-EF 27.4+/-3.0%) training improved VE/VCO2slope from 41.5+/-3.0 to 36.3+/-2.9 (p=0.01 versus control) and the OUES from 1439+/-301 to 1462+/-279 (p = 0.001 vs. control). There was a significant correlation between change in VE/VCO2slope and the change of nt-proBNP (r=0.6; p<0.05). Conclusion(s): Exercise training equally improves ventilatory efficiency in younger and older patients with CHF. These clinical data underline the importance of well dosed exercise-based rehabilitation programs to improve prognosis and quality of life in CHF-Patients. Furthermore, the missing of an age-dependent decline in training response among older patients highlights the importance of exercise interventions in a group with the highest prevalence of CHF.