Evaluation of Cardiac Autonomic Modulation Using Symbolic Dynamics After Cardiac Transplantation

[...]when there is an increase of the low frequency (LF), there must be a reduction of the high frequency (HF), and vice versa, and the sum of LF and HF in normalized units is equal to 100%, characterizing reciprocal changes 5,9. [...]the LF in absolute value (LFabs) index shows information on both sympathetic and parasympathetic modulations7,10. A previous study using pharmacological administration observed that 0V% reflects exclusively sympathetic modulation; 1V% reflects modulation of both pathways; 2LV% also reflects sympathetic and parasympathetic modulations, but this index presents vagal predominance; and the 2UV% index reflects exclusively parasympathetic modulation14. [...]the symbolic analysis shows the sympathetic and parasympathetic modulations on the heart exclusively by the indexes 0V% and 2UV%, respectively14. In this way, the hypothesis of the present study is that the indexes of the symbolic dynamics can be used to characterize the sympathetic and parasympathetic modulations after HTx. [...]the aim of this study is to characterize the profile of cardiac autonomic modulation in individuals with different times after HTx using symbolic dynamics analysis. [...]we put the Chagas disease patients with others and did the analysis that is described below.