Dynamic pulmonary hyperinflation occurs without expiratory flow limitation in chronic heart failure during exercise

Respir Physiol Neurobiol. 2013 Oct 1;189(1):34-41. doi: 10.1016/j.resp.2013.06.017. Epub 2013 Jul 9.

Abstract

To assess the occurrence of tidal expiratory flow limitation (EFL) and/or dynamic pulmonary hyperinflation (DH) in chronic heart failure (CHF) during exercise 15 patients with stable systolic CHF, aged 69 ± 6yr, underwent pulmonary function testing and incremental cardio-pulmonary exercise testing. They subsequently performed constant load exercise testing at 30, 60 and 90% of respective maximum workload. At each step the presence of EFL, by negative expiratory pressure technique, and changes in inspiratory capacity (IC) were assessed. Ejection fraction amounted to 36 ± 6% and VO₂, peak (77 ± 19% pred.) was reduced. EFL was absent at any step during constant load exercise. In 6 patients IC decreased more than 10% pred. at highest step. Only in these patients TLC, FRC, RV FEF(25-75%) and DL(CO) were decreased at rest. VO₂, peak correlated with DL(CO), TLC and IC at rest and with IC (r(2)=0.59; p<0.001) and decrease in IC (r(2)=0.44; p<0.001) at 90% of maximum workload. During exercise CHF patients do not exhibit EFL, but some of them develop DH that is associated with lower VO₂, peak.

Keywords: Chronic heart failure; Exercise; Expiratory flow limitation; Inspiratory capacity; Negative expiratory pressure; Pulmonary hyperinflation.

MeSH terms

  • Aged
  • Exercise / physiology*
  • Female
  • Forced Expiratory Volume / physiology*
  • Heart Failure / complications*
  • Humans
  • Inspiratory Capacity / physiology*
  • Lung / physiopathology*
  • Male