The unnormalized spectral indices of heart rate variability should be presented in conjunction with normalized versions of the same variables

摘要

We thank Kurtoglu et al. [1 ] for their interest in our recent paper on heart rate variability (HRV) in pediatric patients with sleep-disordered breathing (SDB) [2]. SDB is often accompanied by a shift in HRV power from high-frequency (HF) to low-frequency (LF) power; that is, a relatively greater amplitude of slower heart-rate fluctuations and a relatively smaller ampli tude of faster respiratory-related fluctuations. Therefore, we share the view of Kurtoglu et al. [ 1 ] that the relative power in the LF and HF bands are important. For this reason we reported the LF/HF ratio, a measure of the balance between LF and HF components, which we and others interpreted as a balance between sympathetic and parasympathetic arms of the autonomic nervous system [3].