[Dynamics of the indices of spirometry and bicycle ergometry in stenocardia patients undergoing repeated studies]

A study of reproducibility and patterns of change in 7 control bicycle and respiration ergometric tests in 14 coronary anginal patients demonstrated consistent change in stress tolerance and gaseous exchange: a rapid adaptation period (first 2 or 4 tests) when stress tolerance, ventilation and maximum oxygen uptake increased significantly, and a slow adaptation period (most later tests) when tolerance grew gradually, while oxygen consumption first dropped and then stabilized above the baseline. Accidental stress tolerance variation exceeded 1 step in 20% of patients, obviously due to their inability to adapt to the testing procedure. It is suggested that pharmacodynamic studies of antianginal drugs, making use of bicycle and respiration ergometry can only be conducted in the slow adaptation period, provided the individuals showing wide spontaneous variability are excluded from the study.