[Cardiopulmonary exercise test in patients with chronic cardiac failure: comparison with normal subjects and reproducibility of measurements].

The aim of this work was to measure oxygen consumption and carbon dioxide production during exercise in 21 subjects with cardiac failure and 13 normal subjects. During the resting period, subjects with cardiac failure had higher ventilatory frequency and respiratory quotient than normals. During maximal exercise, the former achieved higher ventilatory frequency and oxygen ventilatory equivalent than normals. In subjects with cardiac failure and normals, anaerobic thresholds were 14.4 +/- 0.9 and 28.8 +/- 2.2 ml/kg/min respectively and peak oxygen consumptions 17.1 +/- 1 and 34.4 +/- 1.7 ml/kg/min respectively. There were less than 10% differences in parameters when tests were repeated in 10 subjects with cardiac failure. It is concluded that gas exchange testing may be a reliable and objective assessment method in patients with cardiac failure.