Exercise training improves lung diffusing capacity and exercise ventilation in patients with heart failure

Abstract

Background: In heart failure (HF) patients, benefits deriving from exercise training (ET) programs are multifactorial. It is unexplored whether lung gas exchange and exercise ventilation may benefit from ET and have a role in the patients clinical improvement. Objective: To test whether in stable HF, ET facilitates lung diffusing capacity and ameliorates exercise ventilatory efficiency (VE/VCO2 slope). Methods: Diffusing lung capacity for carbon monoxide (DLco) at rest and its subdivisions (DM, alveolar-capillary membrane conductance, and VC, pulmonary capillary blood volume) as well as VE/VCO2 slope and peak VO2 on exercise (cycle ergometry ramp protocol), were assessed in 15 stable HF patients (NYHA class II to III), preceding and following a low-intensity training program. Results: Baseline DLco (20 ml/min/ mmHg), DM (17 ml/min/mmHg), peak VO2 (16 ml/min/kg) and VE/VCO2 slope (38) were abnormal in these patients. ET was associated with a significant improvement (p 0.01) of DLco ( 20%), peak VO2 ( 21%) time to anaerobic threshold ( 29.4%) and maximal O2 pulse ( 12.3%) and with a significant reduction in VE/VCO2 slope ( 27%). Improvement in DLco was mediated by an increased DM ( 21.6%) despite a reduction in VC ( 16.5%). There were no variations in cardiac index and ejection fraction at rest. Changes in DM correlated with those in VE/VCO2 slope (r 0.88, p 0.002). Conclusions: Although the mechanisms are not completely defined, the evidence is in favor of a beneficial influence of ET programs on the lung pathophysiology in patients with stable HF. An improvement in gas exchange, related to a specific influence on alveolar-capillary membrane conductance, significantly contributes to the amelioration in exercise ventilatory efficiency and functional capacity. Hemoglobin Level is Associated with Adverse Outcomes in Patients with Severe Chronic Heart Failure: Results from the COPERNICUS Study Stefan Anker, Andrew J.S. Coats, Ellen B. Roecker, Paul Mohacsi, Milton Packer5—Clinical Cardiology, NHLI, London, United Kingdom; Faculty of Medicine, University of Sydney, Sydney, Australia; Biostatistics and Medical Informatics, University of Wisconsin, Madison, WI; Department of Cardiology, Inselspital, Bern, Switzerland; Center for Heart Failure Research, College of Physicians and Surgeons, New York, NY