title: Efficacy and safety of implantable cardioverter-defibrillators in patients with Chagas disease.
abstract: OBJECTIVE
  Implantable cardioverter-defibrillators (ICDs) are now a first-line option for prevention of sudden death in Chagas disease (ChD). However, efficacy and safety of ICD treatment in ChD remains controversial. The aim of our study was to compare clinical outcome after ICD implantation in ChD and non-ChD patients.
  
  
  RESULTS
  The study population consists of patients who received ICD implantation in a tertiary Reference Center for ChD in Brazil. The primary endpoint of the study was appropriate therapy (appropriate shocks or anti-tachycardia pacing); the secondary endpoint was the event-free survival defined as absence of death or appropriate therapy. One hundred and thirty-five [corrected] patients were followed for the median time of 266 days. Sixty-five patients had ChD. Appropriate ICD therapy occurred in 32 (49.2%) ChD and in 19 (27.1%) non-ChD patients (P=0.005). Ventricular tachycardia occurred in 27 (42%) ChD and in 16 (23%) non-ChD (P = 0.01) patients. There was a statistically significant difference in event-free survival between the group of patients with and without ChD (P=0.004). The median event-free survival was 230 days (95% confidence interval, CI: 113-347) in patients with ChD and 549 days (95% CI: 412-687) in non-ChD patients. Chagas disease double the risk of the patient to have appropriate therapy (hazard ratio, HR = 2.2, 95% CI = 1.2-4.3, P = 0.02) and appropriate therapy or death (HR = 2.2, 95% CI = 1.2-4.2, P = 0.01) in multivariate analysis. There were 16 deaths (11.8%) with 8 deaths in each group and five inappropriate shocks (3.7%) with one in ChD patients (1.6%).
  
  
  CONCLUSIONS
  The higher frequency of appropriate ICD therapy and the shorter event-free survival in ChD patients are consistent with the presence of an arrhythmogenic substrate that characterizes this cardiomyopathy.
authors: Departamento de Clínica Médica, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil. marcopmed@yahoo.com
authors: Marco Paulo Tomaz
authors: MP
authors: Barbosa
authors: Manoel Otávio
authors: MO
authors: da Costa Rocha
authors: Alexandre Barbosa
authors: AB
authors: de Oliveira
authors: Federico
authors: F
authors: Lombardi
authors: Antonio Luiz Pinho
authors: AL
authors: Ribeiro
mesh_terms: D000368:Aged; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000209:etiology / Q000401:mortality / Q000517:prevention & control*; D001938:Brazil; D002598:Chagas Cardiomyopathy / Q000150:complications / Q000175:diagnosis / Q000401:mortality / Q000628:therapy*; D016757:Death, Sudden, Cardiac / Q000209:etiology / Q000517:prevention & control*; D017147:Defibrillators, Implantable; D018572:Disease-Free Survival; D004554:Electric Countershock / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D062606:Tertiary Care Centers; D013997:Time Factors; D016896:Treatment Outcome
keywords: Chagas disease; Implantable cardioverter defibrillator; Sudden death; Ventricular arrhythmia