[Evaluation of patient-oriented exercise tolerance based on symptoms of patients with heart failure]

Exercise tolerance is one of the most important factors when evaluating patients with heart failure, because it is closely related to their symptoms, Treadmill or ergometer test is usually used to evaluate exercise tolerance. But these tests are painful and sometimes dangerous to the seriously-ill patients. Further exercise tolerance tests reflect the exercise capacity under unusual conditions, which differs greatly from daily activities. So it is very questionable whether we can evaluate actual exercise capacity by exercise tolerance tests. Therefore I devised my own exercise tolerance classification, with 10 Grades according to the symptoms felt during walking. I used this classification for patients with heart failure, and investigated its utility. I studied the correlation between the new classification and the symptom-limited exercise duration in 18 patients, and between the classification and anaerobic threshold in 12 patients. I got good correlation in each of them; (r = 0.842,p less than 0.001) and (r = 0.806, p less than 0.01). The classification also correlated with pulmonary wedge pressure (r = -0.778, p less than 0.05), but it had no correlation with other hemodynamic and morphological parameters. The classification also reflected therapeutic efficacy of heart failure. These results indicate that the new classification is useful in evaluating exercise tolerance without imposing any discomfort on patients with heart failure.