Hyperinflation Impairs Cardiac Performance During Exercise in COPD
This research from Neto et al focuses on the correlation between a plateau in minute ventilation VE during cardiopulmonary exercise tests (CPETs) and its influence on heart performance.
This retrospective study analyzed 2575 CPETs from patients with chronic obstructive pulmonary disease. The study randomly selected 10 patients with a plateau in the VE curve, indicating dynamic hyperinflation, 10 patients with a normal pattern for the VE curve and 10 healthy subjects. The new index for ventilation hyperinflation, classic CPET variables and dynamic cardiac limitation index were analyzed
Patients with dynamic hyperinflation showed lower ventilation with a working rate of 100% (P <.0001), with no significant differences in VE at a working speed of 50% and 100%. Patients with dynamic hyperinflation also presented a lower oxygen pulse (O2 pulse) at 100% (P <.0001), with no significant difference in O2 pulse at 50% and 100% working speed. The subjects with dynamic hyperinflation had a higher ventilation hyperinflation index (P <.0001) and index for dynamic heart disease (P <.0001). The ventilation hyperinflation index correlated with the dynamic cardiac constraint index (r = 0.81, P <0001); oxygen pulse variation (r = -0.63, P <0.001); VE / VCO2 slope (r = -0.57, P <0.01); working speed (r = -0.86, P <.0001); VO2 (r = -0.80, P <.0001) and VE (r = -0.83, P <.0001).
There is a correlation between a plateau in the VE during CPET, which indicates hyperinflation that affects the performance of the heart.