Acute and subacute hemodynamic responses and perception of effort in subjects with chronic Chagas cardiomyopathy submitted to different protocols of inspiratory muscle training: a cross-over trial.

PURPOSE: This study aimed to evaluate acute and subacute hemodynamic responses and perception of effort in individuals with CCC submitted to different IMT protocols. MATERIALS AND METHODS: This was a randomized cross-over trial conducted on CCC subjects with systolic left ventricular dysfunction (<45% left ventricular ejection fraction) without or with heart failure (stages B2 and C, respectively). Twenty-one participants performed two IMT protocols, one targeting 60% maximal inspiratory pressure with 3 × 10 repetitions (MIP60) and the other targeting 30% maximal inspiratory pressure (MIP30) with 3 × 20 repetitions with a 2 min recovery between sets for both. MIP60 and MIP30 were performed on the same day with a 2 h washout period. Measurements were taken at baseline, during and 60 min after IMT. RESULTS: No differences in hemodynamic variables were observed across protocols. The perception of effort increased in both protocols, with higher scores for the MIP30 protocol (ß = +1.6, p = 0.01; ß = +1.1, p = 0.02; ß = +0.9, p = 0.08 for the 1st, 2nd and 3rd sets, respectively). CONCLUSIONS: There were no differences in hemodynamic responses comparing MIP60 and MIP30 protocols in subjects with CCC. Despite the higher perception of effort during endurance protocol, both protocols can be considered a safe therapeutic strategy.IMPLICATIONS FOR REHABILITATIONDespite inspiratory muscle training may result in functional capacity improvements, no previous study evaluated the hemodynamic acute and subacute responses to inspiratory muscle training in chronic Chagas cardiomyopathy.The two inspiratory muscle training protocols (30% and 60% of maximal inspiratory pressure) did not cause significant hemodynamic repercussions in subjects with chronic Chagas cardiomyopathy.Inspiratory muscle training seems to be an effective strategy to improve functional capacity and can be implemented in the rehabilitation programs for patients with Chagas cardiomyopathy.Since no significant adverse responses were observed in any of the hemodynamic parameters during the inspiratory muscle training sessions, these two protocols of inspiratory muscle training (30% and 60% of maximal inspiratory pressure) seems to be safe in subjects with Chagas cardiomyopathy.

Selenium Treatment and Chagasic Cardiopathy (STCC): study protocol for a double-blind randomized controlled trial.

BACKGROUND: Heart disease progression occurs in 30% of patients with chronic Trypanosoma cruzi infection. Supplementation with selenium (Se) in animal model of T. cruzi infection produced promising results. There is evidence that patients with Chagas heart disease have lower Se levels than healthy individuals and patients with T. cruzi infection without of cardiac disease. The aim of this investigation is to estimate the effect of Se treatment on prevention of heart disease progression in patients with chagasic cardiopathy. METHODS: The Selenium Treatment and Chagasic Cardiopathy trial is a superiority, double-blind, placebo-controlled, randomized clinical trial. The eligibility criteria are as follows: (1) a Chagas disease diagnosis confirmed by serology; (2) segmental, mild or moderate global left ventricular systolic dysfunction; and (3) age between 18 and 65 years. The exclusion criteria are as follows: (1) pregnancy, (2) diabetes mellitus, (3) tobacco use, (4) alcohol abuse, (5) evidence of nonchagasic heart disease, (6) depression, (7) dysphagia with evidence of food residues in the esophagus, (8) dysphagia with weight loss higher than 15% of usual weight in the last four months and/or (9) conditions that may result in low protocol adherence. The intervention will be 100 µg of sodium selenite once daily for 365 consecutive days compared to placebo. The following are the primary outcomes to be measured: (1) the trajectories of the left ventricular ejection fraction in the follow-up period; (2) reduction of heart disease progression rates, with progression defined as a 10% decrease in left ventricular ejection fraction; and (3) rate of hospital admissions attributable to dysrhythmia, heart failure or stroke due to Chagas disease. One hundred thirty patients will be randomly allocated into either the intervention or placebo group at a ratio of 1:1. The sequence allocation concealment and blinding were planned to be conducted with the strategy of numbered boxes. Both patients and health-care providers will remain blinded to the intervention groups during the 5 years of follow-up. DISCUSSION: If Se treatment reduces the progression of Chagas cardiopathy, the inclusion of this micronutrient in the daily diet can improve the therapeutic regimen for this neglected tropical disease at low cost. TRIAL REGISTRATION: Clinical Trials.gov ID: NCT00875173 (registered 20 October 20 2008).