Vol 60, No 4 (2004)
Other
Published online: 2005-12-12
Chronic heart failure. The relationship between increased activity of skeletal muscle ergoreceptors and reduced exercise tolerance
DOI: 10.33963/v.kp.81912
Kardiol Pol 2004;60(4):328-332.
Abstract
Background: In chronic heart failure (CHF), skeletal muscle abnormalities may lead to the overactivation of ergoreceptors which in turn may cause sympathetic overactivation and increased ventilatory response to exercise.
Aim: To assess ergoreceptor reflex response to exercise and to evaluate whether ergoreceptor overactivity is related to the progression of CHF.
Methods: In 69 patients with CHF (66 males, mean age 62.7±11.6 years, NYHA class I/II/III/IV - 11/32/24/2 patients, respectively) and 24 controls without CHF (22 males, mean age 59±4.6 years) the ergoreflex contribution to the ventilatory and haemodynamic responses to exercise was evaluated. Moreover, in 13 patients with CHF, reproducibility of the measurements was assessed by repeating the test 1 to 7 days later.
Results: Enhanced ergoreflex effects on ventilation (1.9±1.6 vs 0.14±0.7 l/min, p<0.05) and systolic blood pressure (19.2±14.9 vs 6.1±5.9 mmHg, p<0.05) were found in patients with CHF compared with control subjects. Ergoreceptor overactivity was associated with a worse symptomatic state (NYHA class I vs II vs III, IV: 0.9 vs 1.5 vs 2.9 l/min, p<0.05) and lower exercise tolerance (peak V02: r=-0.51, p<0.0001; VE/VC02: r=0.50, p<0.0001). The mean values of the ergoreceptor reflex did not differ significantly between the two tests (t=1.5, p=0.14; variability coefficient = 21.5%).
Conclusions: In CHF, overactivation of the ergoreflex is associated with the progression of the syndrome and may be responsible for reduced exercise tolerance. Reproducibility of ergoreflex measurements is satisfactory.
Aim: To assess ergoreceptor reflex response to exercise and to evaluate whether ergoreceptor overactivity is related to the progression of CHF.
Methods: In 69 patients with CHF (66 males, mean age 62.7±11.6 years, NYHA class I/II/III/IV - 11/32/24/2 patients, respectively) and 24 controls without CHF (22 males, mean age 59±4.6 years) the ergoreflex contribution to the ventilatory and haemodynamic responses to exercise was evaluated. Moreover, in 13 patients with CHF, reproducibility of the measurements was assessed by repeating the test 1 to 7 days later.
Results: Enhanced ergoreflex effects on ventilation (1.9±1.6 vs 0.14±0.7 l/min, p<0.05) and systolic blood pressure (19.2±14.9 vs 6.1±5.9 mmHg, p<0.05) were found in patients with CHF compared with control subjects. Ergoreceptor overactivity was associated with a worse symptomatic state (NYHA class I vs II vs III, IV: 0.9 vs 1.5 vs 2.9 l/min, p<0.05) and lower exercise tolerance (peak V02: r=-0.51, p<0.0001; VE/VC02: r=0.50, p<0.0001). The mean values of the ergoreceptor reflex did not differ significantly between the two tests (t=1.5, p=0.14; variability coefficient = 21.5%).
Conclusions: In CHF, overactivation of the ergoreflex is associated with the progression of the syndrome and may be responsible for reduced exercise tolerance. Reproducibility of ergoreflex measurements is satisfactory.
Keywords: chronic heart failure - skeletal muscle ergoreceptors
