利用关联维数分析心脏的动力学特征

Applying Correlation Dimension to Analyse the Dynamic Characteristics of the Heart

按照非线性理论设计并实施了用于心脏系统非线性研究的深低温停循环（ＰｒｏｆｏｕｎｄＨｙｐｏｔｈｅｒｍｉａ ａｎｄ Ｃｉｒｃｕｌａｔｏｒｙ Ａｒｒｅｓｔ，简称ＰＨＣＡ） 实验·通过对ＰＨＣＡ 实验中几个温度台阶上所采集的心电信号的关联维数的计算，得出以下结论：（１） 心脏系统的运动落在具有分维的奇怪吸引子上；（２） 心电信号的关联维数反映了心脏的总体动态特征，它可用以估计心脏的健康状态；（３） 在正常的生理状态下心脏的运动是混沌的，而在病理状态下则趋于有序·

According to the nonlinear theory,the profound hypothermia and circulatory arrest (PHCA) experiments were designed to research on the nonlinearity of the heart. The correlation dimension to a large number of cardioelectrical signals sampled on the several temperature platforms of the PHCA experiments was computed,this computation shows:(1) The activities of cardiac system fall on a fractal dimension strange attractor;(2) The correlation dimension of cardioelectrical signals reflects the whole dynamic characteristics of the hearts,and may be used to estimate healthy condition of the heart;(3) On normal physiological conditions the cardiac activities are chaotic,but on pathologic conditions the cardiac activities approach regularity.