Psychophysical power functions of exercise limiting symptoms in coronary heart disease

Thirty consecutive male patients with angiographically determined multivessel disease and ten healthy volunteers were subjected to a symptom limited exercise test with stepwise increments of 10 W every minute. Leg exertion, breathlessness, and chest pain were rated according to a category-ratio scale with 10 degrees and psychophysical power functions computed. Depending on whether chest pain was the limiting symptom, patients were subdivided into groups A (N = 20) and B (N = 10). Exercise capacity did not differ between groups A and B. Both groups terminated the exercise test at lower work loads and lower symptom intensities than the healthy volunteers. Psychophysical power functions were similar for leg exertion in the three groups while the growth of breathlessness was lower in group B. In group A the intensity of chest pain increased more rapidly than leg exertion or breathlessness. In conclusion, those patients with coronary heart disease interrupt the exercise test at lower ratings of leg exertion and breathlessness than healthy volunteers. The psychophysical power functions do not grow more rapidly for these sensory modalities in patients than in healthy volunteers.