Stress testing and working capacity in Chagas' cardiomyopathy.

The EKG response to exercise and the working capacity in a group of 70 patients with positive serology for Chagas' disease has been determined by stress testing on a bicycle-ergometer, in order to establish the usefulness of such a test in the early diagnosis of Chagas' cardiomyopathy. The exercise EKG provides information which cannot be obtained by other diagnostic procedures, since the stress test can induce or increase ventricular arrhythmia, and is particularly indicated in patients with Chagas' infection and the incipient forms of Chagas' cardiomyopathy. Measuring the working capacity is useful in order to establish the degree of functional impairment of each individual patient. After the application of oral digoxin, no significant increase of ventricular extrasystoles following exercise has been observed and the working capacity has improved in the majority of the studied cases with Chagas' cardiomyopathy.