title: Automatic implantable cardioverter-defibrillators in Chagas' heart disease patients with malignant ventricular arrhythmias.
abstract: A total of 46 consecutive Chagas' disease patients had an automatic cardioverter defibrillator implanted at our institution from October 1998 to January 2004. A retrospective longitudinal study was carried out to identity type of life-threatening ventricular arrhythmias as well as type of therapy delivered. Of these, 41 (91%) had been recovered from cardiac arrest. Five (15%) of 33 patients in whom echocardiography was done had no left ventricular function. Antiarrhythmic therapy was delivered to 37 (80%) patients during postimplant follow-up. Thirty-one of 37 (84%) patients received both shock and antitachycardia pacing, five (13%) only antitachycardia pacing, and one (3%) patient only shock. Median time to first shock was 16 days, varying from 1 to 576 days. Ventricular fibrillation was the cause of first shock in 12 patients (32%), ventricular tachycardia in 11 (29%), and ventricular tachycardia not responding to antitachycardia pacing degenerating into ventricular fibrillation in nine (24%). Five patients with ventricular tachycardia were treated with antitachycardia pacing. Probability of freedom from device discharged was 47% at 90 days, 34% at 180 days, and 9% at 360 days in the postimplant follow-up. Thus, patients with chronic Chagas' heart disease recovered from cardiac arrest have a peculiar arrhythmogenic profile characterized by a high frequency of ventricular fibrillation and no left ventricular systolic dysfunction and a short period of time for first shock.
authors.affiliation: Department of Cardiology and Cardiovascular Surgery, Hospital de Base, Sâo José do Rio Preto Medical School, São José do Rio Preto city, Brazil.
authors.forename: Augusto
authors.initials: A
authors.lastname: Cardinalli-Neto
authors.forename: Osvaldo T
authors.initials: OT
authors.lastname: Greco
authors.forename: Reinaldo B
authors.initials: RB
authors.lastname: Bestetti
mesh_terms: D001938:Brazil / Q000453:epidemiology; D002598:Chagas Cardiomyopathy / Q000453:epidemiology* / Q000628:therapy*; D015897:Comorbidity; D017147:Defibrillators, Implantable / Q000706:statistics & numerical data*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000453:epidemiology* / Q000517:prevention & control*