title: The effect of beta-blockade on myocardial remodelling in Chagas' cardiomyopathy.
abstract: OBJECTIVE
  Chagas' disease has spread throughout Latin America because of the high rate of migration among these countries. Approximately 30% of Chagas' patients will develop cardiomyopathy, and 10% of these will develop severe cardiac damage leading to heart failure. Beta-blockade improves symptoms and survival in heart failure patients; however, its efficacy has not been well established in Chagas' disease. We evaluated the role of carvedilol in cardiac remodeling and mortality in a Chagas' cardiomyopathy animal model.
  
  
  METHODS
  We studied Trypanosoma cruzi infection in 55 Syrian hamsters that were divided into three groups: control (15), infected (20), and infected + carvedilol (20). Animals underwent echocardiography, electrocardiography, and morphometry for collagen evaluation in ventricles stained with picrosirius red.
  
  
  RESULTS
  The left ventricular diastolic diameter did not change between groups, although it was slightly larger in infected groups, as was left ventricular systolic diameter. Fractional shortening also did not change between groups, although it was slightly lower in infected groups. Collagen accumulation in the interstitial myocardial space was significantly higher in infected groups and was not attenuated by carvedilol. The same response was observed in the perivascular space. The survival curve showed significantly better survival in the control group compared with the infected groups; but no benefit of carvedilol was observed during the study. However, in the acute phase (up to 100 days of infection), carvedilol did reduce mortality.
  
  
  CONCLUSIONS
  Carvedilol did not attenuate cardiac remodeling or mortality in this model of Chagas' cardiomyopathy. The treatment did improve survival in the acute phase of the disease.
authors.affiliation: Unidade Clínica de Miocardiopatias, Hospital das Clínicas Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil.
authors.forename: Walace de Souza
authors.initials: Wde S
authors.lastname: Pimentel
authors.forename: Felix José Alvarez
authors.initials: FJ
authors.lastname: Ramires
authors.forename: Barbara Maria
authors.initials: BM
authors.lastname: Lanni
authors.forename: Vera Maria Cury
authors.initials: VM
authors.lastname: Salemi
authors.forename: Angelina Morand Bianchi
authors.initials: AM
authors.lastname: Bilate
authors.forename: Edecio
authors.initials: E
authors.lastname: Cunha-Neto
authors.forename: Adriana Morgan de
authors.initials: AM
authors.lastname: Oliveira
authors.forename: Fábio
authors.initials: F
authors.lastname: Fernandes
authors.forename: Charles
authors.initials: C
authors.lastname: Mady
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000818:Animals; D002227:Carbazoles / Q000627:therapeutic use*; D000077261:Carvedilol; D002598:Chagas Cardiomyopathy / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D003094:Collagen / Q000032:analysis; D006224:Cricetinae; D004195:Disease Models, Animal; D004452:Echocardiography; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006352:Heart Ventricles / Q000503:physiopathology; D053208:Kaplan-Meier Estimate; D008647:Mesocricetus; D011412:Propanolamines / Q000627:therapeutic use*; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome; D020257:Ventricular Remodeling / Q000187:drug effects*
chemical_list: D000319:Adrenergic beta-Antagonists; D002227:Carbazoles; D011412:Propanolamines; D000077261:Carvedilol; D003094:Collagen