RESUMO
BACKGROUND: Chagas cardiomyopathy (CCM) is increasingly prevalent in developed countries due to migration from endemic areas. Accurate risk stratification is crucial due to the variable clinical course of CCM. OBJECTIVE: To analyze the association between Rassi score progression and electrophysiology study (EPS) changes in CCM patients. METHODS: This prospective, observational cohort study involved CCM patients from two tertiary hospitals. Patients were classified as low, intermediate, or high risk based on the Rassi score. Data collected included demographics, clinical history, and diagnostic tests. EPS assessed AH, HH, and HV intervals, and inducibility of ventricular arrhythmias. Follow-ups were at 30 days and six-month intervals, with individualized discussions for cardiac implantable electric devices (CIED) based on EPS results. RESULTS: Of 67 screened CCM patients, 59 underwent EPS. The mean Rassi score was 8.7 ± 4.5 points, with 33.8 % low, 38.9 % intermediate, and 27.1 % high risk. EPS abnormalities were found in 57.6 % of patients, mainly VT/VF (52.5 %). Most induced ventricular arrhythmias were monomorphic VT (80.7 %). A significant association was found between Rassi score risk classification and EPS changes (OR = 1.88 95 %CI: 1.15-3.06 p = 0.02). Higher Rassi scores correlated with VT presence on EPS (p = 0.0036). Syncope/pre-syncope had an OR 2.45 95 %CI:1.21-4.94; p = 0.012, independent of Rassi risk. Decreased ejection fraction was linked to EPS changes (p = 0.04). CONCLUSION: EPS changes among CCM was associated with progression of the Rassi score, indicating its utility as a stratification tool. Factors such as the presence of syncope/pre-syncope, decreased LVEF and wall motion abnormalities emerged as independent predictors within Rassi scores for changes in EPS.