[Anaerobic threshold in patients with chronic circulatory insufficiency]

To evaluate the severity of chronic circulatory insufficiency (CCI), 12 healthy subjects and 69 patients with cardiovascular diseases underwent exercise testing. Parameters such as anaerobic threshold (AT) and peak oxygen consumption (peak VO2) were measured by respiratory gas analysis to assess the circulatory insufficiency. AT decreased with an increase in New York Heart Association functional class and amounted to 18.9 +/- 4.3, 14.5 +/- 3.5, 11.6 +/- 2.9, and 7.5 +/- 2.0 ml/min/kg in Classes 1, 2, 3, 4, respectively. The peak VO2 decreased as hCCI progressed. The findings suggest that the parameters of external respiration and gas exchange are closely associated with CCI pathophysiology. The parameters may be used as objective and valid criteria for the severity of CCI and its dynamics in the course of treatment.