Assuntos
Cardiomiopatia Chagásica/fisiopatologia , Doença de Chagas/fisiopatologia , Animais , Sistema Nervoso Autônomo/fisiopatologia , Pressão Sanguínea , Doença de Chagas/mortalidade , Circulação Coronária , Frequência Cardíaca , Ventrículos do Coração/fisiopatologia , Humanos , Contração Miocárdica , Esforço Físico , Renina/sangueAssuntos
Humanos , Masculino , Feminino , Cardiomiopatia Chagásica , Doença de Chagas , Análise AtuarialAssuntos
Adulto , Pessoa de Meia-Idade , Idoso , Humanos , Masculino , Feminino , Colelitíase , Doença de ChagasRESUMO
The prevalence of slow heart rate was investigated among 222 patients with Chagas' disease, 50 normal subjects, and 55 patients with non-chagasic heart failure. In any decade of life the basal heart rate of patients with chagasic heart failure was always significantly lower (P less than 0.001) than the basal heart rate of non-chagasic heart failure patients, and also lower than the basal heart rate of normal subjects. There were no significant differences between chagasic patients without heart failure and normal subjects. It is concluded that patients with heart failure of chagasic etiology show slow heart rates.
Assuntos
Bradicardia/etiologia , Doença de Chagas/fisiopatologia , Adulto , Fatores Etários , Idoso , Doença de Chagas/complicações , Doença Crônica , Insuficiência Cardíaca/etiologia , Frequência Cardíaca , Humanos , Pessoa de Meia-IdadeRESUMO
The purpose of this study was to investigate the sympathetic nervous system function in 34 patients with chronic Chagas' disease. The tilting test was selected as an appropriate means to assess the adrenergic system function. Our results demonstrate that (a) all chagasics respond with a significantly smaller rise in diastolic blood pressure (0-3.8 mmHg) than normal subjects (9-12 mmHg), when submitted to the tilting test and (b) chagasic patients with heart failure have a significantly lower heart rate than normal subjects and nonchagasic heart failure patients (P < 0.05 and 0.001, respectively). With these results we may speculate that the damage in chronic Chagas' disease should be located in the sympathetic pathway. Therefore, the faulty orthostatic mechanism would be the consequence of a diminished adrenergic activity, with a defective arteriolar vasoconstriction and a decreased basal heart rate. At the same time we note that our results differ from the results of similar tests performed on the same kind of chagasic patients in Brazil, where a predominantly decreased parasymphathetic activity has been demonstrated.
