Is Chagas cardiomyopathy an independent risk factor for patients with heart failure?

Some studies showed increased mortality in chagasic patients but most of these studies did not perform statistical adjustments to socioeconomic variables. The main objective of this study was to investigate if there is an independent association between Chagas etiology and mortality in patients with heart failure and moderate to severe left ventricle systolic dysfunction. Stratified analysis by the variables associated to chagasic etiology and multivariate analysis through logistic regression were performed to evaluate the relationship between Chagas cardiomyopathy and one-year mortality. Among 417 patients initially evaluated, 191 had the inclusion criteria. The mortality was higher in patients with Chagas cardiomyopathy than in the patients with other etiologies (log rank test; p=0.036). At one-year follow-up, the mortality in chagasic patients was 21.6% versus 10.6% in the remaining (relative risk=2.03; 95% CI=0.98-4.2; p=0.05). At logistic regression, educational level was identified as a confounder variable of the association between Chagas cardiomyopathy and one-year mortality. This association was no more statistically significant after adjustment for educational level (odds ratio=1.67; 95% CI=0.63-4.41). In this study, Chagas cardiomyopathy was a marker of worse prognosis, but was not independently associated to increased one-year mortality in outpatients with heart failure and moderate to severe systolic dysfunction.