Non-linear dynamics in heart rate variability of normal subjects and chagasic patients

Tachograms of two groups, one consisting of 15 chagasic patients (Group II) and the second group consisting of 18 healthy persons as a control group, were investigated. The tachograms (R-R intervals) were obtained from high resolution ECG. Statistical analysis of the first Lyapunov exponent and complexity changes through symbolic dynamics showed that parameters obtained from non-linear analysis could be used to discriminate between chagasic patients and healthy persons.