Pathogenesis of chronic Chagas heart disease.
BACKGROUND
Chagas disease remains a significant public health issue and a major cause of morbidity and mortality in Latin America. Despite nearly 1 century of research, the pathogenesis of chronic Chagas cardiomyopathy is incompletely understood, the most intriguing challenge of which is the complex host-parasite interaction.


RESULTS
A systematic review of the literature found in MEDLINE, EMBASE, BIREME, LILACS, and SCIELO was performed to search for relevant references on pathogenesis and pathophysiology of Chagas disease. Evidence from studies in animal models and in anima nobile points to 4 main pathogenetic mechanisms to explain the development of chronic Chagas heart disease: autonomic nervous system derangements, microvascular disturbances, parasite-dependent myocardial aggression, and immune-mediated myocardial injury. Despite its prominent peculiarities, the role of autonomic derangements and microcirculatory disturbances is probably ancillary among causes of chronic myocardial damage. The pathogenesis of chronic Chagas heart disease is dependent on a low-grade but incessant systemic infection with documented immune-adverse reaction. Parasite persistence and immunological mechanisms are inextricably related in the myocardial aggression in the chronic phase of Chagas heart disease.


CONCLUSIONS
Most clinical studies have been performed in very small number of patients. Future research should explore the clinical potential implications and therapeutic opportunities of these 2 fundamental underlying pathogenetic mechanisms.
Marin-Neto
Jose Antonio
JA
Cardiology Division, Department of Internal Medicine, Medical School of Ribeirão Preto, University of São Paulo, São Paulo, Brazil. marin_neto@yahoo.com
Cunha-Neto
Edécio
E
Maciel
Benedito C
BC
Simões
Marcus V
MV
D000818:Animals; D000913:Antibodies, Protozoan / Q000276:immunology; D015551:Autoimmunity; D001341:Autonomic Nervous System / Q000503:physiopathology; D002598:Chagas Cardiomyopathy / Q000188:drug therapy / Q000209:etiology* / Q000276:immunology / Q000503:physiopathology; D006224:Cricetinae; D016757:Death, Sudden, Cardiac / Q000209:etiology; D003714:Denervation; D006321:Heart / Q000469:parasitology; D006329:Heart Conduction System / Q000503:physiopathology; D006790:Host-Parasite Interactions; D006801:Humans; D051379:Mice; D008833:Microcirculation; D023421:Models, Animal; D008955:Models, Cardiovascular; D008959:Models, Neurological; D018716:Molecular Mimicry; D017202:Myocardial Ischemia / Q000209:etiology / Q000503:physiopathology; D009205:Myocarditis / Q000209:etiology / Q000469:parasitology; D009206:Myocardium / Q000276:immunology / Q000473:pathology; D009593:Nitroimidazoles / Q000627:therapeutic use; D010275:Parasympathetic Nervous System / Q000503:physiopathology; D016176:T-Lymphocyte Subsets / Q000276:immunology; D014344:Trypanocidal Agents / Q000627:therapeutic use; D014349:Trypanosoma cruzi / Q000276:immunology / Q000502:physiology; D014611:Vaccination; D018487:Ventricular Dysfunction, Left / Q000209:etiology
D000913:Antibodies, Protozoan; D009593:Nitroimidazoles; D014344:Trypanocidal Agents; C009999:benzonidazole