Relationship between age and the energy density distribution of fundamental and harmonic frequency component in electrocardiogram energy spectrum / 生物医学工程学杂志

ABSTRACT

In a least square method, an exponential function fits the energy density distribution of fundamental and harmonic frequency component in a long-term ECG energy spectrum. A distributing index of the function was used to quantify divergence and convergence degree of energy density. The function fits locally the ECG energy spectrum data that were collected from the young (21-34 yr) group and elderly (68-81 yr) group rigorously energy density ratio of the harmonic to fundamental frequency component and recognizability number of harmonic frequency component were significantly less in the young group than in the elderly group (P < 0.01), the center frequency f0 and energy density at center frequency f0 did not differ between the two age groups. These data indicate that the characteristic parameter values presented in this study can serve as a new measurement of heart rate fluctuations.