Due to the lack of information in the literature about the role of cardiac rehabilitation on Chagas heart failure, the aim of the present study was to evaluate the effects of a cardiac exercise program on functional capacity, cardiac function, respiratory muscle strength, body composition, biomarkers and quality of life among Chagas heart failure patients.

The present study consisted in a pre/post single-arm intervention study conducted at the Evandro Chagas National Institute of Infectious Disease (INI), located on Rio de Janeiro, Brazil. INI is a national reference center for treatment and research in infectious diseases and tropical medicine in Brazil, which follows a large cohort of patients with Chagas disease, all of them diagnosed by two simultaneously positive serological tests (enzyme-linked immunosorbent assay and indirect immunofluorescence). Patients included in the study were submitted to a physical exercise intervention protocol performed three times per week, 60 minutes per session, during an 8-month period. Nutritional and pharmaceutical counseling were also monthly provided during the follow-up and consisted on general guidance about adequate eating habits for patients with heart failure, mainly sodium and water intake, and medication usage, particularly drug dosage and compliance.Patients included in the study were followed during an 8-month period in which evaluations of functional capacity (maximal progressive cardiopulmonary exercise test), muscle respiratory strength (manovacuometry) and body composition (anthropometry and skinfolds) were performed at baseline, after four months and at the end of follow-up. Assessments of cardiac function (bidimensional echocardiography), biomarkers (lipid profile, glucose and glycated hemoglobin) and quality of life (Minnesota Living with Heart Failure questionnaire) were taken at baseline and after eight months of follow-up.

Inclusion Criteria:

• Patients at the stages C or D of Chagas cardiomyopathy
• Patients receiving standard optimized medical therapy
• Patients with good adherence to outpatient treatment within the last three months.

Exclusion Criteria:

• Those who were not able to attend three weekly training sessions,
• Those who had neuromuscular limitations, cardiopathies from non-Chagasic etiology (e.g ischemic), systemic conditions that limits exercise practice (e.g chronic obstructive pulmonary disease)
• Practitioners of regular exercise.