Effects of Different Interventions on Cardiac Regulation Using Fuzzy Entropy

Abstract

Although psychological distress is associated with heart rate variability (HRV) and can be improved by interventions, few studies compared the effects of different interventions on cardiac regulation and the changes of the complexity of HRV in pre-, during-, and post-intervention phases. In this paper, 18 healthy young participants were recruited to investigate the effects of deep breathing, meditation, and video-watching tasks. The respiration (RSP) and electrocardiogram (ECG) signals were simultaneously recorded. Fuzzy entropy (FuzzyEn) was applied to quantify the complexity of HRV in pre-, during-, and post-task phases. The results showed that the FuzzyEn value of HRV in the during-task phase was significantly lower than that in the pre-task phase in deep breathing, video-watching, and meditation tasks, which might result from the effect of cardiorespiratory coupling (CRC), brain-heart coupling (BHC), and the combined effect of CRC and BHC, respectively. There were also significant increases of the FuzzyEn value in the post-task phase than the during-task phase in the deep breathing and meditation tasks, while the lower FuzzyEn value in the post-task phase than during-task phase only occurred in the video-watching task, which might result from that watching video had a more lasting impact on HRV than the other two tasks due to the brain memory. The method and indicator provide the evidence of cardiac rhythm changes after different interventions, and further research was needed to promote the clinical application.