title: On- and off-exercise kinetics of cardiac output in response to cycling and walking in COPD patients with GOLD Stages I-IV.
abstract: Exercise-induced dynamic hyperinflation and large intrathoracic pressure swings may compromise the normal increase in cardiac output (Q) in Chronic Obstructive Pulmonary Disease (COPD). Therefore, it is anticipated that the greater the disease severity, the greater would be the impairment in cardiac output during exercise. Eighty COPD patients (20 at each GOLD Stage) and 10 healthy age-matched individuals undertook a constant-load test on a cycle-ergometer (75% WR(peak)) and a 6min walking test (6MWT). Cardiac output was measured by bioimpedance (PhysioFlow, Enduro) to determine the mean response time at the onset of exercise (MRTon) and during recovery (MRToff). Whilst cardiac output mean response time was not different between the two exercise protocols, MRT responses during cycling were slower in GOLD Stages III and IV compared to Stages I and II (MRTon: Stage I: 45±2, Stage II: 65±3, Stage III: 90±3, Stage IV: 106±3s; MRToff: Stage I: 42±2, Stage II: 68±3, Stage III: 87±3, Stage IV: 104±3s, respectively). In conclusion, the more advanced the disease severity the more impaired is the hemodynamic response to constant-load exercise and the 6MWT, possibly reflecting greater cardiovascular impairment and/or greater physical deconditioning.
authors.affiliation: Department of Physical Education and Sports Sciences, National and Kapodistrian University of Athens, Greece.
authors.forename: M K
authors.initials: MK
authors.lastname: Vasilopoulou
authors.forename: I
authors.initials: I
authors.lastname: Vogiatzis
authors.forename: I
authors.initials: I
authors.lastname: Nasis
authors.forename: S
authors.initials: S
authors.lastname: Spetsioti
authors.forename: E
authors.initials: E
authors.lastname: Cherouveim
authors.forename: M
authors.initials: M
authors.lastname: Koskolou
authors.forename: E A
authors.initials: EA
authors.lastname: Kortianou
authors.forename: Z
authors.initials: Z
authors.lastname: Louvaris
authors.forename: G
authors.initials: G
authors.lastname: Kaltsakas
authors.forename: A
authors.initials: A
authors.lastname: Koutsoukou
authors.forename: N G
authors.initials: NG
authors.lastname: Koulouris
authors.forename: M
authors.initials: M
authors.lastname: Alchanatis
mesh_terms: D000222:Adaptation, Physiological; D000368:Aged; D001642:Bicycling; D002302:Cardiac Output / Q000502:physiology*; D016022:Case-Control Studies; D015444:Exercise / Q000502:physiology*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006439:Hemodynamics; D006801:Humans; D008297:Male; D016555:Matched-Pair Analysis; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000145:classification / Q000503:physiopathology*; D012016:Reference Values; D015656:Respiratory Mechanics; D012720:Severity of Illness Index; D013318:Stroke Volume / Q000502:physiology*; D016138:Walking