The aim of this study was to assess the peripheral and cardiac autonomic system by catecholamine measurements in patients with severe chagasic and nonchagasic heart failure. Fifteen chagasic and 16 nonchagasic patients were enrolled in the study. Plasma venous norepinephrine levels (pg/ml) were 397.26 ± 250.11 for chagasic and 660.05 ± 455.57 for nonchagasic patients (p > 0.05), plasma venous epinephrine levels 215.84 ± 254.04 for chagasic and 106.17 ± 65.90 for nonchagasic patients (p > 0.05), aortic root norepinephrine levels 435.46 ± 306.60 for chagasic and 668.16 ± 512.82 for nonchagasic patients (p > 0.05), aortic root epinephrine levels 300.33 ± 302.69 for chagasic and 199.98 ± 162.88 for nonchagasic patients (p > 0.05), coronary sinus norepinephrine levels 636.10 ± 495.22 for chagasic and 552.17 ± 535.54 for nonchagasic patients (p > 0.05) and coronary sinus epinephrine levels 226.66 ± 277.47 for chagasic and 69.21 ± 35.62 for nonchagasic patients (p = 0.02). Myocardial and peripheral norepinephrine and epinephrine extractions were similar for both groups. Taken together, these findings may suggest that chagasic patients with congestive heart failure have biochemical evidence of cardiac autonomic dysfunction with preservation of the peripheral sympathetic activity.