[Circulation and heart rate variability at three hemodynamic patterns of juvenile age]

The study involved 135 apparently healthy students 17 - 21 years old. Bioimpedance tetrapolar rheopolygraphy based on Kentavr computer system was employed in studied subjects in supine position at rest. Examined subjects, regarding their percental volume of cardiac index (CI) - 25 and 75, were included into three groups with hypokinetic (CI was lower than 2.0 L/min/m2), eukinetic (CI ranged from 2.0 to 3.0 L/min/m2) and hyperkinetic (CI was more than 3.0 L/min/ m2) hemodynamic pattern. The evaluation of blood flow indices showed that heart rate, stroke volume, minute blood volume, cardiac index, rheogram amplitude were lower in hypokinetic type, but photoplethysmogram was higher when compared with both eukinetic and hyperkinetic types. Power spectral analysis of heart rate variability demonstrated that components of heart rate power frequencies, absolute values of the heart rate power oscillations at four frequencies ranges (UVLF, VLF, LF, HF) as well as relative values of heart rate power spectrum in LF and VLF were lower, but relative values of high-frequency components were higher compared to other two hemodynamic patterns. These data demonstrate that hypokinetic type of circulation was sparer in healthy subjects of juvenile age.