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A simple risk score was developed to predict death in Chagas' heart disease and was validated in an independent cohort.

and Venezuela have the domestic, peridomicile and sylvatic cycles, with high prevalence of human infection and prevalence of chronic Chagas' cardiomyopathy (CCC).Group II -Colombia, Costa Rica and Mexico, characterized by domestic and peridomicile cycles with presence of CCC.Group III -El Salvador, Guatemala, Nicaragua and Panama have domestic, peridomicile and sylvatic cycles with poor clinical information. AbstractMuch has been achieved in one century after Carlos Chagas' discovery. However, there is surely much to be done in the next decades. At present, we are witnessing many remarkable efforts to monitor the epidemiology of the disease, to better understand the biology of the T. cruzi and its interaction with human beings as well as the pathogenesis and pathophysiology of the complications in the chronic phase, and deal more appropriately and effectively with late cardiac and digestive manifestations.

Background-QT interval parameters are potential prognostic markers of arrhythmogenicity risk and cardiovascular mortality and have never been evaluated in Chagas' disease. Methods and Results-Outpatients (738) in the chronic phase of Chagas' disease were enrolled in a long-term follow-up study. Maximal heart rate-corrected QT (QTc) and T-wave peak-to-end (TpTe) intervals and QRS, QT, JT, QTapex, and TpTe dispersions and variation coefficients were measured manually and calculated from 12-lead ECGs obtained on admission. Clinical, radiological, and 2-dimensional echocardiographic data were also recorded. Primary end points were all-cause, Chagas' disease-related, and sudden cardiac mortalities. During a follow-up of 58Ϯ39 months, 62 patients died, 54 of Chagas' disease-related causes and 40 suddenly. Multivariate Cox survival analysis revealed that the QT-interval dispersion (QTd) (hazard ratio, 1.45; 95% confidence interval, 1.29 to 1.63; PϽ0.001, for 10-ms increments) and left ventricular (LV) end-systolic dimension (hazard ratio, 1.36; 95% confidence interval, 1.21 to 1.53; PϽ0.001, for 5-mm increments) were the strongest independent predictors for all end points. The maximum QTc interval (QTcmax) could substitute for QTd with a worse predictive performance. Other predictors were heart rate, presence of pathological Q waves, frequent premature ventricular contractions (PVCs), and isolated left anterior fascicular block (LAFB) on the ECGs. Kaplan-Meier survival curves demonstrated that a QTd Ն65 ms or a QTcmax Ն465 ms 1/2 discriminated the 2 groups with significantly different prognoses. Conclusions-Electrocardiographic QTd and echocardiographic LV end-systolic dimension were the most important mortality predictors in patients with Chagas' disease. Heart rate, the presence on ECG of pathological Q waves, frequent PVCs, and isolated LAFB refined the mortality risk stratification. (Circulation. 2003;108:305-312.)