Dynamic Hyperinflation Impairs Cardiac Performance During Exercise in COPD

PURPOSE: To investigate the correlation between a plateau in minute ventilation (Equation is included in full-text article.)E 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 (Equation is included in full-text article.)E curve, suggesting dynamic hyperinflation, 10 patients with normal pattern for the (Equation is included in full-text article.)E 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 (Equation is included in full-text article.)E 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); (Equation is included in full-text article.)E/(Equation is included in full-text article.)CO2 slope (r =-0.57, P < .01); work rate (r =-0.86, P < .0001); (Equation is included in full-text article.)O2 (r =-0.80, P < .0001), and (Equation is included in full-text article.)E (r =-0.83, P < .0001). CONCLUSION: There is a correlation between a plateau in the (Equation is included in full-text article.)E during CPET, suggesting hyperinflation, and it has an impact on cardiac performance.