Long-term symbolic dynamics for heart rate variability analysis in patients with dilated cardiomyopathy

This study was designed to improve the prognostic value of heart rate variability (HRV) in patients with dilated cardiomyopathy (DCM) using a new method of long-term symbolic dynamics. DCM patients show a decreased HRV in comparison to healthy subjects (p<0.03). A lower ejection fraction leads to a further reduction in HRV (p<0.01). Moreover, the DCM patients exhibit a decreased low frequency component (p<0.001). The Renyi-entropy of the word distribution as a method of long-term symbolic dynamics show the most significant differences between the LVEF<27% and >27% group (p<0.001). The new non-linear method of symbolic dynamics leads to an increased diagnostic precision in characterizing DCM patients.