The Peculiarities of the Endothelial Function, Blood Lipid Spectrum and Heart Rate Variability in Patients with Stable Angina, Depending on the Heart Rate Frequency

• Main Authors: Bilous Z., Аbrahamovych О.
• Format: Article
• Language: English
• Published: Publishing House "Kyrylytsya" 2016-12-01
• Series: Львівський клінічний вісник
• Subjects: blood lipid spectrum; endothelial dysfunction; heart rate; heart rate variability; stable angina
• Online Access: http://lkv.biz/the-peculiarities-of-the-endothelial-function-blood-lipid-spectrum-and-heart-rate-variability-in-patients-with-stable-angina-depending-on-the-heart-rate-frequency/

The survey studies the impact of heart rate on the development of endothelial dysfunction and disorders of heart rate variability in patients with stable angina. Introduction. Endothelium plays an important role in the adaptation of coronary blood flow to myocardial oxygen demand in case of angina pectoris. In case of damage there is an imbalance between the level of endothelium synthesized substances – imbalance between vasodilators and vasoconstrictors towards increased synthesis of vasoconstrictors, which plays a signifi cant role in causing stenosis of coronary arteries, affected by atherosclerosis. The loss of endothelial anti-inflammatory, antioxidant and antithrombotic capacity causes disorders of perfusion, tissue hypoxia. Episodes of transient coronary artery vasoconstriction deepen inadequate coronary blood flow, further limiting it. Increased heart rate mechanically damages the vascular wall, causing endothelial dysfunction. High heart rate can affect hemostasis, promote destabilization and rupture of an atherosclerotic plaque. Purpose of the study. To evaluate the peculiarities of the endothelial function, blood lipid spectrum and heart rate variability in patients with stable angina, depending on the heart rate frequency. Materials and research methods. The study involved 125 patients with stable angina, which were divided into groups, depending on the magnitude of heart rate. The control group consisted of 34 practically healthy persons surveyed comparable according to age and sex. The average heart rate in patients of groups 1, 2 and 3 was, on average, 89.9 ± 6.57 bpm, 70.26 ± 4.37 bpm and 58,0 ± 1,12 bpm respectively, in the control group – 70.7 ± 5.4 bpm (p1.4 < 0.05, p2,4 > 0.05, p3,4 < 0.05). Serum ELISA determined endothelin-1; method for determining the activity of vWF is based on its ability to induce platelet aggregation in the presence of aggregation inducer ristozitine; the study of blood lipid spectrum was carried out by using spectrophotometric method; studying heart rate variability, we analysed the temporal and spectral characteristics. Statistical analysis of the results of research was carried out by the variation statistics method using Statistica 6.0 and Microsoft Offi ce Excel 2007. Results of the investigation and their discussion. In patients with stable angina endothelial dysfunction was pronounced. In patients with stable angina with a heart rate >80 bpm endothelial dysfunction was more pronounced (increased content of endothelin-1 – 5.85 ± 0.31 fmol/ml (р1,2 < 0.01, р1,3 < 0.01) and von Willebrand factor – 186.3 ± 11.0 % (р1,2 < 0.01, р1,3 < 0.01), and more significant pro-atherogenic changes of blood lipid spectrum (increased LDL-C, TG). Between HR end E-1, vW direct relationship. LDL-Cin 1 group 4.27 ± 0.34 mmol/l and 4.12 ± 0.18 and 3.04 ± 0.25 mmol/lin 2 and 3 (р1,2 > 0.05, р1,3 < 0.01). TGin 1 group 2.19 ± 0.08 mmol/l, in 2 group – 1.98 ± 0.06, and in 1 group – 1.90 ± 0.04 (р1,2 < 0.05, р1,3 < 0.01). In patients with stable angina pro-atherogenic changes in lipid spectrum was pronounced. Between HR, LDL-C and TG established a direct relationship. Based on the study of spectral and temporal characteristics of heart rate variability there was found an autonomic imbalance in these patients with a predominance of sympathetic nervous system activity. Between HR and heart rate variability the temporal and spectral characteristics direct relationship. In patients with a heart rate of 60-80 and <60 beats per min. endothelial dysfunction was less pronounced, however, decrease of the level of parasympathetic ANS impact in the regulation of cardiac activity was found. Platelets and index of aggregation does not indicate the existence of substantial differences in surveyed groups. Conclusions. Patients with stable angina have features of endothelial function, lipid spectrum of the blood and heart rate variability depending on heart rate, which are in the most significant signs of endothelial dysfunction, violation of lipid spectrum of the blood and the imbalance of autonomic nervous system dominated symptomatic level in patients with the frequency of heart rate over 80 beats / minute, and it can be used as a criterion for assessing the severity of the pathogenic mechanisms of stable angina.