RESUMO
BACKGROUND: Ventricular tachycardia (VT) is one of the main predictors of mortality in Chagas cardiomyopathy (CC). Although the substrate of sustained and nonsustained-VT (NS-VT) seems to be the same, little is known about the distribution of late enhancement (LE). Our aim was to compare the clinical findings and the amount and patterns of LE in Chagas disease according to the presence and type of VT. METHODS AND RESULTS: Magnetic resonance imaging was performed in 54 Chagas seropositive patients: 8 indeterminate and 46 with CC of whom 15 were without VT, 13 with NS-VT, and 18 with sustained-VT (S-VT). There were 31 males (57%), mean age was 55.9 ± 12.2 years. LE was found in 87% of all patients and in 50%, 80%, and 100% of the indeterminate, without VT and VT groups, respectively. The percentage of LE increased progressively in the indeterminate, CC without VT, and CC with VT groups; without a significant difference between NS-VT and S-VT (0.93%, 15.2%, 23.2%, and 21.4%, respectively). The amount of LE increased with the functional class. LE in the basal and mid lateral wall was more frequent in VT, without difference between S-VT and NS-VT. The only predictor of VT was the percentage of LE, odds ratio (OR), 6.2; (95% confidence interval [CI], 3.7-28.4; P = .01) with a cutoff of Odds Ratio 17.1%. CONCLUSIONS: The amount of LE increases in relation to the clinical stage of the disease and its functional class in Chagas seropositive patients. The amount of LE was the main predictor of VT, without difference between S-VT and NS-VT.
