Application Of The Wavelet Transform To The HRV Signal Analysis Of Druggers

The analysis of heart rate variability (HRV) has become an important tool for non-invasively detecting the cardiovascular modulation of autonomic nervous system. HRV refers to the tiny fluctuations of instantaneous heart rate between consecutive beats or the minor differences of the successive cardiac cycles. It contains a lot of information concerning the cardiovascular regulation, while extracting and analyzing of the information of HRV can offer a quantitative evaluation of the tenseness and the balance of the sympathetic and the vagus nerve activities and their effect on cardiovascular motion. Clinical medicine has given the evidence that investigating HRV has an important meaning not only for the early diagnosing cardiovascular disease, monitoring during convalescence and evaluating after recuperation, but also for the quantitatively valuing the cardiac functions during physical exercises or in other special environment.The reasons of fluctuations of heart rate are complicated. The influence of sympathetic and parasympathetic nerve caused by various factors can all lead to its oscillations. Hence, the frequency components contained in HRV are never invariable, but time-variant. In other words, the signal of HRV is a nonstationary signal.We main study the heroin addict's HRV signal. At present, it is nearly reporting in this domain. HRV signal is get from RR interval of electrocardiogram in a traditional method, in this article, HRV signals are obtained from human pulses BB interval. It has been proved that the two method is uniform in essence, the length of heart beats determine the length of the pulse. Using two threshold-value to extract BB interval of human pulses and interpolated by cubic spline before being evenly re-sampledIn this article, we develop some kinds of methods to analyze heroin addicts HRV signals basing on Multi-resolution analysis and wavelet packet analysis and aim to extract some abnormal information. First, using Multi-resolution analysis, the HRV signals of 22 heroin druggers and 22 normal persons are decomposed into 6 scale and calculated the power of each wavelet coefficient and scaling coefficient for heroin duggers, except for the cd3 and cd4, are all greater than the corresponding values for normal persons. Secondly, using the wavelet packet transform with db2 wavelet, decomposed into 5 levels. At level 5, it is found that the mean values of the standard deviation of the decomposition coefficients in subspaces U 00 , U01, ,U07 for heroin druggers, except for subspaces U₀⁵, U₀⁶ and U₀⁷, are all greater than the corresponding values for normal persons.