[Chronodiagnostic potentialities of the symbolic dynamics method]

To assess diagnostic potential of cardiac rhythm symbolic dynamics.

PhysyoNet base data on ECG heart rhythm for 24 hours were analysed by characteristics of the symbolic lines: size of vocabularies and entropic properties of symbol distribution in the lines. The following ECGs were analysed: 54 ECGs of healthy individuals with normal sinus rhythm aged 28.5-76 years; 44 ECGs of patients with congestive cardiac failure aged 34-79 years; 84 ECGs of patients with cardiac fibrillation aged 34-79 years; 19 ECGs of patients with sudden cardiac death syndrome aged 34-79 years.

The index of variety of cardiac rhythm regulation is proposed which is effective not only for analysis of 24-h but also of 40-60 min rhythmograms.

The quantitative analysis of symbolic dynamics can be used for differential chronodiagnosis of different cardiac diseases. Application of words which vary by length allows examination of rhythms with different time scale, detection and comparison of hierarchical desynchronization.