Cardiopulmonary exercise testing characteristics in heart failure patients with and without concomitant chronic obstructive pulmonary disease

Background: The assessment of aerobic exercise capacity is an important component in the clinical management of patients with heart failure (HF). Although a significant percentage of patients diagnosed with HF also present with chronic obstructive pulmonary disease (COPD) comorbidity, the combined impact of these chronic conditions on the aerobic exercise response is unknown and is therefore the purpose of the present investigation. Methods: Sixty-nine subjects with HF and COPD were matched to 69 subjects solely diagnosed with HF according to age, sex, and HF etiology. All subjects underwent resting pulmonary function and diffusion capacity testing, echocardiography with tissue Doppler imaging, and cardiopulmonary exercise testing (CPX). Results: Subjects with COPD comorbidity had significantly lower pulmonary function testing and diffusion capacity values versus HF alone (P <.05). In addition, subjects with both HF and COPD had significantly higher pulmonary artery systolic pressures (51.9 ± 9.0 vs 37.0 ± 7.8 mm Hg, P <.001) as assessed by pulsed Doppler echocardiography. Cardiopulmonary exercise testing revealed a significantly poorer response in subjects with HF and COPD by all variables that were analyzed, including peak oxygen consumption (12.1 ± 4.3 vs 16.3 ± 4.3 mL kg^-1 min^-1, P <.001), minute ventilation/carbon dioxide production slope (42.7 ± 7.4 vs 33.3 ± 6.6, P <.001) and heart rate recovery at 1 minute (12.1 ± 2.5 vs 14.2 ± 2.9 beats, P <.001). Conclusions: Patients with HF and the comorbidity of COPD have significantly impaired CPX responses. This novel finding may impact the clinical interpretation of CPX data in patients with HF who also present with this chronic pulmonary condition.