Effects of an exercise program on the functional capacity of patients with chronic Chagas' heart disease, evaluated by cardiopulmonary testing

Abstract

Introduction: Despite all efforts to restrict its transmission, Chagas' disease remains a severe public health problem in Latin America, affecting 8-12 million individuals. Chronic Chagas' heart disease, the chief factor in the high mortality rate associated with the illness, affects more than half a million Brazilians. Its evolution may result in severe heart failure associated with loss of functional capacity and quality of life, with important social and medical/labor consequences. Many studies have shown the beneficial effect of regular exercise on cardiac patients, but few of them have focused on chronic Chagas' heart disease. Methods: This study evaluated the effects of an exercise program on the functional capacity of patients with chronic Chagas' disease who were treated in outpatient clinics at the Evandro Chagas Institute of Clinical Research and the National Institute of Cardiology, Rio de Janeiro, Brazil. The exercises were performed 3 times a week for 1 h (30 min of aerobic activity and 30 min of resistance exercises and extension) over 6 months in 2010. Functional capacity was evaluated by comparing the direct measurement of the O 2 uptake volume (VO 2 ) obtained by a cardiopulmonary exercise test before and after the program (p < 0.05). Results: Eighteen patients (13 females) were followed, with minimum and maximum ages of 30 and 72 years, respectively. We observed an average increase of VO 2peak > 10% (p = 0.01949). Conclusions: The results suggest a statistically significant improvement in functional capacity with regular exercise of the right intensity.

Effect of physical exercise training in patients with Chagas heart disease: study protocol for a randomized controlled trial (PEACH study)

“…We hypothesize that exercise training will be safe and promote improvements in functional capacity and quality of life, as previously demonstrated by Lima et al [11] and Fialho et al [12] in a different sample of patients with CHD. Since an exacerbated inflammatory response is an important mechanism involved in the development of CHD [46] and because several studies have been demonstrating an important anti-inflammatory property of exercise training [47], a decrease in the serum levels of pro-inflammatory cytokines and an increase in the serum levels of anti-inflammatory cytokines in patients with CHD in the exercise group is expected.…”

“…The first study that addressed the effects of exercise training on CHD showed that functional capacity, clinical symptoms, and some domains of health-related quality of life (vitality, emotional aspects, and mental health) improved after 3 months of follow-up [11]. Another single-arm study demonstrated that oxygen consumption at peak of exercise (VO 2 peak), oxygen pulse (O 2 pulse), and oxygen consumption at anaerobic threshold (VO 2 AT) improved after 6 months of exercise training [12]. However, the interpretation of these results is limited by the short-term follow-up in the former study and the lack of a control group in the later study.…”

Reassessment of quality of life domains in patients with compensated Chagas heart failure after participating in a cardiac rehabilitation program

“…Cardiac rehabilitation has emerged as an important strategy to decrease mortality and improve QOL in patients with heart failure, mostly heart failure of ischemic etiology 6,7 . However, the few trials that have evaluated the effects of cardiac rehabilitation on patients with Chagas heart failure have presented several methodological shortcomings 8,9 .…”

Cardiac rehabilitation program in patients with Chagas heart failure: a single-arm pilot study

“…Patients included in the exercise training group exhibited improvements in estimated VO 2 max, 6-minute walk test distance, symptom severities, and the vitality, emotional functioning, and mental health domains of health-related quality of life. Similarly, in a single-arm study, Fialho et al (18) observed improvements in peak VO 2 , oxygen pulse (an indirect measure of cardiac function), and O 2 consumption at anaerobic threshold after 6-months of exercise training. However, a lack of direct measurements of cardiac function, the short-term follow-up period and the characteristics of patients included in these studies, most of them in the early stages of Chagas cardiomyopathy and without HF, limits the applicability of the results and reinforces the necessity for more research in this area.…”

“…However, the majority of studies that have evaluated CR in HF have failed to include patients with Chagas disease, and the few studies evaluating the effects of exercise training on patients with Chagas disease have been limited by short-term followup (≤ 6 months), the lack of echocardiographic evaluation, and the inclusion of patients in the early stages of Chagas cardiomyopathy or even those without evidence of cardiac disease (16) (17) (18) (19) (20) . Therefore, the safety and efficacy of CR among patients with CHF remains unknown.…”