The haemodynamic response to exercise in chronic obstructive pulmonary disease: assessment by impedance cardiography

This study aimed to determine the differences in haemodynamic responses to a standard incremental exercise test between outpatients with chronic obstructive pulmonary disease (COPD) and age-matched controls and to discover the relationship between severity of airflow obstruction and exercise haemodynamics in COPD, Twenty-two male patients with COPD (forced expiratory volume in one second (FEV1)/vital capacity (VC)) < 80% predicted) and 20 age-matched male controls performed an incremental exercise test (10 W.min(-1) with ventilatory function and changes in stroke volume (Delta SV) and cardiac output (Delta CO) measured by means of electrical impedance cardiography (EIC). Submaximal Delta SV and Delta CO were lon er in COPD patients. Peak exercise Delta SV were equal in patients and controls (128+/-33 versus 129+/-29%,p=0.98), whereas peak Delta CO was lower in patients (COPD versus controls: 232+/-71 versus 289+/-54%, p<0.005). In COPD patients, FEV1 (% pred) was significantly correlated to Delta SV at all submaximal exercise intensities, to peak exercise Delta SV and to peak exercise Delta CO. FEV1/VC (% pred) was significantly correlated to Delta SV at 30 and 60 W. In conclusion, in chronic obstructive pulmonary disease an aberrant haemodynamic response to exercise was found, especially in patients with severe airflow obstruction. This aberrant response is related to the degree of airflow obstruction and may limit exercise performance in patients dth severe chronic obstructive pulmonary disease.