A Algorithm for Spectral Analysis of Instantaneous Heart Rate

This work studied the lomb method for investigating the spectral behavior of instantaneous heart rate(IHR), and the ECG recordings were taken from the patients suffered from obstructive sleep apnea syndrome(osas). In order to derive the characteristic spectrum of osas patient and get over the inherent defect of the lomb method, the work present a new algorithm, which first removed the rhythmic oscillations (mainly respiratory oscillations) by the empirical mode decomposition (EMD) method, and then investigated the spectrum of the residual component of IHR. The results showed that the method can effectively get over the disturbance of rhythmic oscillations of IHR, and distinctly reflect the characteristic spectrum of osas patient. On the other hand, the work post that there was an excess power in a frequency band between 0.02 Hz and 0.04 Hz when osas patient is asleep during apnea episodes, and this powers was maximum in most case.