Analysis of R-R interval spectrum power based on empirical mode decompositions

  AIM  To present a method to well evaluate autonomic nerve system (ANS) activity based on respiration.

  METHODS  R-R intervals were divided into respiration-related (HFr) components and respiration-unrelated (LFu) components with empirical mode decompositions (EMD). They were used to evaluate the ANS activity in slowly deep breath (SDB) and mental arithmetic test (MAT).

  RESULTS  Power spectrum components of RR interval were successfully divided into HFr parts and LFu parts based on the relationship between intrinsic mode function (IMF) and maximum respiratory slope. The HFr and LFu power spectrums well evaluated the ANS activity in SDB and MAT, compared with the heart rate variability (HRV) power spectrum.

  CONCLUSION  The respiration-related and respiration-unrelated power spectrums could be used to evaluate sympathetic and parasympathetic activities.