Estimation of Approximate Entropy of Heart Rate Variability of Healthy Subjects and Investigation of the Effect of Meditation on It

The human heart is a nonlinear system because the heart rhythm is modulated by the Autonomic nervous system (ANS). The modulation of the heart rate about its mean value is called Heart rate variability (HRV). Nonlinear analysis of HRV is helpful to assess the cardiac health noninvasivly. The autonomic dysfunction also causes cardiac malfunction. The effect of ANS on cardiac functioning is investigated by estimating Approximate entropy (ApEn) of HRV data of a few healthy subjects before and after meditation. It has been found that the entropy parameters indicate improved cardiac health after meditation. Which means the heart rhythm was more dynamic after meditation ApEn is estimated by assuming that the data is stationary.