O efeito da estimulação elétrica ventricular direita em pacientes com insuficiência cardíaca crônica sistólica secundária à cardiomiopatia chagásica

Abstract

Background: Chagas disease is a public health and social problem in Latin America due to its high incidence, morbidity and mortality. Chagas cardiomyopathy is manifested mainly by sudden cardiac death, chronic systolic heart failure, thromboembolism, ventricular arrhythmias and advanced atrioventricular block. The right ventricular pacing is a common treatment modality in patients with chronic systolic heart failure secondary to Chagas cardiomyopathy with advanced atrioventricular block. However, it is unknown if the clinical course or the prognosis of patients with right ventricular pacing is worse than that seen in non-paced patients. Aim: Establish the role of permanent pacemaker implantation on the prognosis of patients with Chagas disease heart failure. Methods: All patients with chronic systolic heart failure secondary to Chagas cardiomyopathy followed at our institution between January 2000 and December 2008 were considered for the study. A model of Cox proportional hazards regression was used to determine the role of right ventricular pacing as an independent predictor of all-cause mortality in this population. The Kaplan-Meier curves were constructed to estimate the probability of survival in patients with and without right ventricular pacing, which were compared by the log rank test. Results: A total of 216 patients were enrolled; 116 (55%) were not treated with right ventricular pacing, but 100 (45%) patients were paced. One hundred and ten (51%) patients died during the study. No difference was observed in the mortality rate in paced (54%) in comparison to non-paced (56%) (p = 0.24). Pacemaker therapy for ventricular pacing was not a predictor of all-cause mortality in either univariate or multivariate analysis. Median follow-up was 19 (8, 43) months.