Kardialni autonomni regulace u nemocnych s ischemickou chorobou srdecni. Hodnoceni variability srdecni frekvence v kratkodobych zaznamech.

The work deals with the spectral analysis of heart rate variability (HRV), one of the methods assessing the autonomic neural regulations. The review of the recent knowledge is referred in the first - theoretic part. The assessment of short-term HRV in patients surviving the myocardial infarction (MI) is repoeted in the second part of the work. The spectral analysis of HRV was made during the SUPINE-STANDING-SUPINE test to standardize the examination conditions and to improve the effectivity of the method by measuring the HRV in two different situations (standing with the prevailing sympathetic effect; lying down - e.g. supine with the prevailing parasympathetic effect). There were measured five-minute electrocardiographic recordings in steady state in the standing and following supine position. By the method of modified fast Fourier transformation analysis there were analysed these spectral components in the spectral range 0,02-0,4Hz: the component of very low frequency, spectral range 0,02-0,05Hz, the component of low frequency, spectral range 0,05-0,15Hz and the component of high frequency, spectral range 0,15-0,4Hz. Each component was characterized by spectral power in the absolute and in the relative values, by the ratios of absolute values of the components and coefficient of variation of each component. The parameter MSSD (mean of the sum of the squares of differences between adjacent normal R-R intervals) was used as the representative of the analysis in the time domain.Available from STL Prague, CZ / NTK - National Technical LibrarySIGLECZCzech Republi