Abstract
Changes in the regulation and functions of vascular endothelium were studied in 169 acute coronary syndrome (ACS) patients. Based on coronary angiography results, the patients were divided into two groups: with or without verified hemodynamically significant constriction of coronary arteries (HSCCA). Judgments about vegetative nervous functions were derived from cardiac rhythm variation analyzed according to P. M. Bayevskiy under basal conditions and upon cold stress. The parameters of vascular endothelial functions assessed in the study included circulating endothelial cell counts, blood nitric oxide metabolites, blood Willebrand factor, and endothelium-dependent vasodilation. It was found that, in patients having no HSCCA, vegetative dysfunctions manifested as signs of increased sympathetic and parasympathetic tone were more pronounced. We suggest that one of the mechanisms of ACS development in such patients may involve interactions between the vegetative nervous system and the endothelium, which result in sustained vasospasm.