Piezopulsometric Analysis of Autonomous Regulation of the Cardiovascular System in an Elderly Person under Stress

The results of the application of a new method of arterial piezopulsometry for noninvasive assessment of the functional state and physiological mechanisms of autonomous regulation of the cardiovascular system (CVS) in an elderly person with acute pain associated with unexpected physical trauma are described. Such exposure caused a negative stress response in the muscle effectors (MEs) of CVS on the first day, provoking an abnormal increase and acceleration of LV myocardial contractility. Analysis of the arterial blood pressure pulse (PP) wave graphs shows that the maximum rate of PP growth, VmaxPP, reflecting the myocardial contractility, increased from 625 ± 74 before the trauma to 2117 ± 173 mm Hg/s after the trauma, distorting the waveform of the normal graph. The cause of this increase could be the rapid total effect of transmitters of the neuroendocrine sympathoadrenal system on the adrenergic receptors (ARs) of cardiomyocytes (CMs). The results of the spectral analysis of the variability of the PP wave parameters confirm this possibility. It is shown that under stress, norepinephrine from activated sympathetic efferents is added to the already increased content of humoral catecholamines in the extracellular environment of the myocardium near ARs of CMs, which is typical for older people. At the same time, the activity of parasympathetic efferents that release acetylcholine, which inhibits the contractile reaction of the myocardium and, thereby, performs a restraining cardioprotective function, significantly increases. A personalized approach was used to study the mechanisms of autonomous regulation of CVS MEs under stress.