The pattern of myocardial fibrosis in chronic Chagas' heart disease

Avaliação do metabolismo dos fosfatos de alta energia em pacientes com doença de Chagas

“…Such alterations were less severe than those presented by patients with myocardial dysfunction, but still statistically significant. A possible explanation for this finding is the presence of myocardial degenerative impairment in the early stages of Chagas' disease 6,32 demonstrated by the alterations found within the myocyte nucleus, in the T-tubule system and in mitochondrias, as well as by the alterations in the functions of ATPase myosin, monoamine oxidase and succinate dehydrogenase enzymes, involved in the maintenance of cellular energy homeostasis 32 . The inflammatory process in Chagas' cardiomyopathy is also more intense and persistent than in idiopathic dilated cardiomyopathy, accounting for the highest degree of fibrosis and microcirculatory impairment detected by comparative studies performed by biopsy in these two pathologies 33 .…”

“…The pathogenesis of Chagas' heart disease is not established, and the proposed mechanisms are [3][4][5][6] : direct aggression to the myocardium by T. cruzi; neurogenic hypothesis based on phosphocreatine (PCr) 13 . Thus, phosphorus-31 magnetic resonance spectroscopy (MRS) enables the evaluation of high-energy phosphates found in the myocardium, allowing the identification of metabolic changes in patients with different degrees of myocardial impairment 14,15 .…”

“…intense neuronal depopulation found in the different stages of the disease; autoimmune mechanism related to the finding of antibodies directed against antigens of T. cruzi present in foci of myocardial inflammation; damaged coronary microcirculation with consequent development of myocardial ischemia [5][6][7][8][9][10] .…”

Chagas heart disease: pathophysiologic mechanisms, prognostic factors and risk stratification

“…Another important feature of CHD is a marked reparative and reactive fibrosis, characterised by a diffuse and dense interstitial accumulation of collagen that encloses individual fibres or groups of fibres (Rossi 1991). All areas of the heart, including the conduction system, may be involved.…”

“…CHD is an acquired inflammatory cardiomyopathy characterised by a chronic fibrosing myocarditis (varying from focal or multifocal to diffuse) and a progressive impairment of myocardial contractile function (Rossi 1991). Numerous contributing mechanisms have been suggested to explain the pathogenesis of CHD (MarinNeto et al 2007).…”