Dynamic Hyperinflation Impairs Cardiac Performance During Exercise in COPD.

PURPOSE: To investigate the correlation between a plateau in minute ventilation VE during cardiopulmonary exercise tests (CPETs) and its impact on cardiac performance.

METHODS: This retrospective study analyzed 2575 CPETs of patients with chronic obstructive pulmonary disease. The study randomly selected 10 patients with a plateau in the VE curve, suggesting dynamic hyperinflation, 10 patients with normal pattern for the VE curve, and 10 healthy persons. Classic CPET variables, the new ventilation hyperinflation index, and the dynamic cardiac constraint index were analyzed.

RESULTS: The patients with dynamic hyperinflation presented with lower ventilation at 100% work rate (P < .0001), without significant differences in VE at 50% and 100% work rate. Patients with dynamic hyperinflation also presented with a lower oxygen pulse (O2 pulse) at 100% (P < .0001), without significant difference in O2 pulse at 50% and 100% work rate. The subjects with dynamic hyperinflation had a higher ventilation hyperinflation index (P < .0001) and dynamic cardiac constraints index (P < .0001). The ventilation hyperinflation index correlated with the dynamic cardiac constraints index (r = 0.81, P < .0001); oxygen pulse variation (r =-0.63, P < .001); VE/VCO2 slope (r =-0.57, P < .01); work rate (r =-0.86, P < .0001); VO2 (r =-0.80, P < .0001), and VE (r =-0.83, P < .0001).

CONCLUSION: There is a correlation between a plateau in the VE during CPET, suggesting hyperinflation, and it has an impact on cardiac performance.