title: Beta-blocker therapy and mortality of patients with Chagas cardiomyopathy: a subanalysis of the REMADHE prospective trial.
abstract: BACKGROUND
  Peculiar aspects of Chagas cardiomyopathy raise concerns about efficacy and safety of sympathetic blockade. We studied the influence of beta-blockers in patients with Chagas cardiomyopathy.
  
  
  RESULTS
  We examined REMADHE trial and grouped patients according to etiology (Chagas versus non-Chagas) and beta-blocker therapy. Primary end point was all-cause mortality or heart transplantation. Altogether 456 patients were studied; 27 (5.9%) were submitted to heart transplantation and 202 (44.3%) died. Chagas etiology was present in 68 (14.9%) patients; they had lower body mass index (24.1+/-4.1 versus 26.3+/-5.1, P=0.001), smaller end-diastolic left ventricle diameter (6.7+/-1.0 mm versus 7.0+/-0.9 mm, P=0.001), smaller proportion of beta-blocker therapy (35.8% versus 68%, P<0.001), and higher proportion of spironolactone therapy (74.6% versus 57.8%, P=0.003). Twenty-four (35.8%) patients with Chagas disease were under beta-blocker therapy and had lower serum sodium (136.6+/-3.1 versus 138.4+/-3.1 mEqs, P=0.05) and lower body mass index (22.5+/-3.3 versus 24.9+/-4.3, P=0.03) compared with those who received beta-blockers. Survival was lower in patients with Chagas heart disease as compared with other etiologies. When only patients under beta-blockers were considered, the survival of patients with Chagas disease was similar to that of other etiologies. The survival of patients with beta-blockers was higher than that of patients without beta-blockers. In Cox regression model, left ventricle end-diastolic diameter (hazard ratio, 1.78; CI, 1.15 to 2.76; P=0.009) and beta-blockers (hazard ratio, 0.37; CI, 0.14 to 0.97; P=0.044) were associated with better survival.
  
  
  CONCLUSIONS
  Our study suggests that beta-blockers may have beneficial effects on survival of patients with heart failure and Chagas heart disease and warrants further investigation in a prospective, randomized trial. Clinical Trial Registration- clinicaltrials.gov. Identifier: NCT00505050.
authors.affiliation: Heart Failure Institute do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil. victor.issa@incor.usp.br
authors.forename: Victor S
authors.initials: VS
authors.lastname: Issa
authors.forename: Alexandre F
authors.initials: AF
authors.lastname: Amaral
authors.forename: Fátima D
authors.initials: FD
authors.lastname: Cruz
authors.forename: Silvia M A
authors.initials: SM
authors.lastname: Ferreira
authors.forename: Guilherme V
authors.initials: GV
authors.lastname: Guimarães
authors.forename: Paulo R
authors.initials: PR
authors.lastname: Chizzola
authors.forename: Germano E C
authors.initials: GE
authors.lastname: Souza
authors.forename: Fernando
authors.initials: F
authors.lastname: Bacal
authors.forename: Edimar A
authors.initials: EA
authors.lastname: Bocchi
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D015992:Body Mass Index; D002598:Chagas Cardiomyopathy / Q000188:drug therapy* / Q000401:mortality; D005260:Female; D006333:Heart Failure / Q000188:drug therapy* / Q000401:mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D000319:Adrenergic beta-Antagonists