Heart rate variability: for real doctors. Translation from the Russian version of the book, published at Kharkiv, 2010, 131 p.
The basics and practice of the clinical use of the technology of heart rate variability are outlined for doctors of all specialties and students of medical faculties of universities.
9. Regulation in the disease
Approach at heart rhythm disorder
The value of frequency-adaptive reactions. Available in the majority of patients with AF in an active orthostatic test, positive frequency-adaptive responses in HR are explaining in the partial preservation of vegetative regulation in this syndrome.
The latter is confirmed by the results of an acute pharmacological test with propranolol, when the reactions of the heart rate, the total power of the HRV spectrum and the powers of its spectral domains not only in a lying position but also orthostasis, correspond to those with sinus rhythm.
In case of AF, beta-adrenergic blocker propranolol reduces HR, increases the overall power of the HRV spectrum, redistributing its power towards the relative increase in VLF, while orthostatic reactions, as in sinus rhythm, to receive the drug are not violating.
The decrease in the TP of the HRV spectrum in active orthostasis, determined in the case of a positive reaction, qualitatively corresponds to the characteristic patients with sinus rhythm with the vegetative regulation preserved in full.
There is a clear negative relationship between the frequency of positive orthostatic reactions and the severity of arterial hypertension, on the one hand, and their identical rates for different functional classes of stable angina, on the other.
The rigid negative relationship in the frequencies of positive frequency-adaptive reactions and the functional class of HF deserves special attention.
With an increase in FC of HF from I to III, the frequency of positive reactions decreases by 30%, and therefore one of the possible reasons for the decline in the quality and life expectancy of patients with HF is the loss of positive frequency-adaptive reactions as a necessary condition for an adequate hemodynamic response to stress.