PT  - JOURNAL ARTICLE
AU  - Arnoldus van Gestel
AU  - Florent Baty
AU  - Anne-Kathrin Rausch-Osthoff
AU  - Martin Brutsche
TI  - Cardiopulmonary and gas-exchange responses during the 6-minute walk test in patients with chronic obstructive pulmonary disease
DP  - 2014 Sep 01
TA  - European Respiratory Journal
PG  - P2103
VI  - 44
IP  - Suppl 58
4099  - http://erj.ersjournals.com/content/44/Suppl_58/P2103.short
4100  - http://erj.ersjournals.com/content/44/Suppl_58/P2103.full
SO  - Eur Respir J2014 Sep 01; 44
AB  - Background: There is limited information about the cardiopulmonary- and gas exchange responses to the 6-minute walk test (6MWT) in patients with Chronic Obstructive Pulmonary Disease (COPD)Objectives: To analyze the breath-by-breath cardiopulmonary- and gas exchange responses of patients with COPD during the 6MWT. In addition, we have investigated the extent to which parameters reflecting cardiopulmonary- and gas exchange function are associated with exercise capacity.Methods: Oxygen uptake (VO2) kinetics of patients were obtained using mobile telemetric cardiopulmonary monitoring (MOB) during a 6MWT. A new mean response time (MRT) index (wMRT) was developed to quantify VO2 on-kinetics by correcting MRT for work rate. Linear multivariate regression analysis was performed to assess the association between variables reflecting cardiopulmonary- and gas exchange function and exercise capacity (6-minute walking distance, 6MWD and oxygen uptake at steady state, VO2SS).Results: In 72 patients with COPD (29 females) with a mean (SD) age 65 (10) years, FEV1 44 (14) %predicted exercise capacity as assessed by VO2SS (p=0.003) was significantly reduced across the stages of COPD. 82% of the patients reached criteria for maximal effort during the 6MWT. After adjustment for covariates, wMRT was independently associated with 6MWD (p=9.7x10-5) and VO2SS (p=5.5x10-10)Conclusions: As wMRT mostly depends on the rate of increase of pulmonary blood flow, the results of the present study underline the fact that cardiocirculatory function may play a significant role in exercise tolerance in patients with COPD.