HEART RATE VARIABILITY: CLASSIFICATION AND DYNAMIC SYSTEM ANALYSIS

The proposed classification of dynamic HRV processes is based on M-indexes: |М|<0.03 ? linear, station-ary; 0.3>|М|>0.03 ? weakly nonlinear, quasi stationary; 3>|М|>0.3 ? nonlinear, transient; |М|>3 ? strongly nonlinear, transient. The character of M-index gives following interpretation for direction of dynamic HRV process (integrated for analyzing record): ?+? ? accelerating; ??? ? decelerating. Thus M-indexes introduce generalized basis for allocation of HRV stationary processes: М0 indexes ? determine as stationary the whole class on inertial movements in HRV, i.e. movement with constant speed or stochastic vibrations around un-changed frequency; М1 indexes ? determine as stationary the whole class of periodical and quasi periodical movements in HRV, the movements which keep constant phase flow what can be achieved by introducing of time arrow; М indexes ? consider the whole system of appointed above stationary processes in HRV.