Decreased ventilatory efficiency during incremental exercise in bronchiectasis

Bronchiectasis is characterized by aberrant bronchial dilatation (1). The structural changes have been associated with ventilatory dysfunction, exercise intolerance and ventilatory inhomogeneity (2,3) that may aggravate during exercise. A decreased ventilatory efficiency, reflected by the high carbon dioxide ventilatory equivalent (VE/VCO2), has been identified during incremental exercise in patients with COPD, especially when complicated with heart failure (4). At earlier stages of bronchiectasis, exercise intolerance might have become evident before cardiovascular complications developed (5). The mechanisms underlying exercise intolerance in patients with bronchiectasis without heart failure are, however, not entirely clear. By using incremental cycle ergometer, we determined the ventilation-gas exchange abnormalities in patients with bronchiectasis not complicated with physician-diagnosed heart failure