RT Journal Article
SR Electronic
T1 The effect of coexisting chronic heart failure (CHF) in exercise ventilatory inefficiency in patients with COPD
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP P3958
VO 42
IS Suppl 57
A1 Arbex, Flávio Ferlin
A1 Alencar, Maria Clara N.
A1 Oliveira, Mayron F.
A1 Souza, Aline S.
A1 Medeiros, Wladimir M.
A1 Mazzuco, Adriana
A1 Siqueira, Gabriela O.
A1 Mancuso, Frederico J.A.
A1 Nery, Luiz Eduardo
A1 Almeida, Dirceu R.
A1 Neder, J. Alberto
YR 2013
UL http://erj.ersjournals.com/content/42/Suppl_57/P3958.abstract
AB Background: Increase in “wasted” ventilation (VE) during exercise – as a consequence of large dead space to tidal volume ratio – is a common feature of chronic obstructive pulmonary disease (COPD) and CHF. Coexistence of COPD and CHF, therefore, could be associated with greater increases in exercise VE relative to both oxygen uptake (VO2) and carbon dioxide output (VCO2) compared to COPD alone. Objective: To investigate the role of ventilatory inefficiency during incremental exericse in suggesting the presence of CHF in patients with established COPD. Methods: Twenty-four males (13 with COPD-CHF (FEV1= 59.6 ± 17.5 % pred; left ventricle ejection fraction (LVEF) = 34 ± 6 %) and 10 with COPD alone (FEV1= 48.6 ± 16.0 % pred; LVEF= 64 ± 4 %) were submitted to a ramp-incremental cardiopulmonary exercise test. Results: COPD-CHF patients had shallower Δ VO2 /Δ work rate (WR) and lower peak VO2 than their counterparts (p<0.05). In line with our hypotheses, measures of excessive exercise ventilation relative to both VO2 and VCO2 were more disturbed in COPD-CHF than COPD patients (ΔVE/ΔVCO2= 39± 10 vs. 30 ± 6 (p<0.05) and VO2 efficiency slope (OUES, L/min/log)= 1.35± 0.38 vs. 1.76 ± 0.42 (p<0.01), respectively. In addition, decreases in ΔVO2 /ΔWR and OUES were more closely related to peak VO2 in COPD-CHF than in COPD (r= 0.72 vs. 0.24 and 0.80 vs. 0.68, respectively).Conclusions: Pulmonary ventilation increases out of proportion of both VCO2 and VO2 during progressive exercise in COPD plus CHF patients compared to COPD alone. These results suggest that ventilatory inefficiency variables might be helpful in indicating the coexistence of CHF in COPD patients.