Characteristics Of Cardiovascular System Research Articles

Характеристики функціонального та структурно-функціонального стану серцево-судинної системи хворих при ішемічній хворобі серця та ожирінні

The purpose of the study was to determine the changes in the functional and structural-functional state of the cardiovascular system of individuals with ischemic heart disease against the background of obesity. Materials and methods. 105 people of the diagnostic group were examined: 70 people with ischemic heart disease and obesity (1st diagnostic group) and 35 patients with ischemic heart disease without obesity (2nd diagnostic group), who were treated in the municipal non-commercial enterprise «City Clinical Hospital No. 27» of Kharkiv Regional Council. In the 1st diagnostic group, the majority of patients with I (26 (37.1%) degree of obesity, unlike II (24 (34.3%) and III (20 (28.6%). The control group was formed by 35 healthy persons without any diseases of the cardiovascular system. In the 1st diagnostic group there were 51 (72.9%) ill female and 19 (27.1%) male, in the 2nd – 24 (68.6%) male and 11 (31.4%) female. Age of the 1st and 2nd diagnostic groups amounted to 63.6±8.8 and 69.7±7.9 years respectively, and the control group – 35.2±4.9 years. Body weight and body weight index (p < 0.001) was higher in the 1st diagnostic group (respectively 101.3±15.8 kg and 36.2±4.4 kg/m2) compared to the 2nd (respectively 71.9±8.8 kg and 24.2±1.4 kg/m2) and control (respectively 64.3±7.4 kg and 22.1±1.2 kg/m2). Results and discussion. The presence of arrhythmic disorders of cardiovascular system in coronary heart disease was noted, especially against the background of obesity. The predominance of the cardiovascular system characteristics of the functional state in coronary heart disease with obesity in comparison with the monocurrent coronary heart disease has been determined: accordingly, diastolic arterial pressure is 91.7±7.8 and 89.3±9.1 mmHg; heart frequency – 81.9±11.2 and 78.8±9.5 b/min and pulse 81.2±9.8 and 78.2±9.6 b/min. The advantage of cardiovascular system characteristics in obesity of the III degree in comparison with the II and I degrees is fixed: accordingly, systolic arterial pressure is 160.0±15.9, 158.8±16.1 and 152.7±11.8 mmHg; diastolic arterial pressure – 93.5±8.1, 91.9±8.8 and 90.19±6.6 mmHg; heart rate – 82.0±7.4, 81.4±10.6 and 82.3±14.2 b/min and pulse – 82.0±7.4, 81.0±10.3 and 80.8±11.2 b/min. Conclusion. A reliable possibility of provoking significant reductions in the characteristics of the heart functional state in patients with coronary heart disease and obesity compared with the control group was determined. There is a significant advantage of changes in the structural characteristics of the heart in coronary heart disease and obesity and monocurrent coronary heart disease in contrast to the control group. Significant (p < 0.001) increase in aortic diameter was determined in patients with single coronary heart disease (3.30±0.33 cm) and on the background of obesity (3.22±0.29 cm) compared with the control group (2.86±0.14) and intentionally comparable values of E and A and their ratios in the 1st and 2nd groups (respectively E 0.71±0.18 and 0.69±0.17 cm/s (p = 0.463); A – 0.81±0.19 and 0.85±0.24 cm/s (p = 0.342) and E/A – 0.90±0.27 and 0.82±0.27 (p = 0.102). The predominance of the structural and functional state of the heart values in III and II degrees of obesity compared to I degree was intentionally determined

Cardiohemodynamics and gas analysis rearrangements in response to re-breathing in young males of Russia’s Fareast

The objective of this study was to examine the changes occurred in the heart rate variability, cardiovascular system and gas analysis in response to the test with return breathing in young Caucasian and Native men residing in Magadan region and Chukotka Autonomous District. Methods — Total 345 young men were examined; of them 65 were Native people from Chukotka Autonomous District (ChAD) and 35 Natives from Magadan Region (MR) as well as Caucasians (48 from ChAD and 197 from MR, respectively). Results — Studies have shown that in response to the hypoxic-hypercapnic effect, there were changes in the cardiovascular system, heart rate and gas analysis, with a number of differences depending on ethnicity and the region of residence. Region-related features of cardiohemodynamics were manifested by a more pronounced increase in the systolic blood pressure and heart rate in response to the re-breathing test in the two ethnic groups living in ChAD, which was observed against the background of higher values of the difference “baseline-test” in carbon dioxide levels in the exhaled air. Ethnic differences in our studies were seen due to the pronounced increase in response to the test for the activity of the parasympathetic link of the autonomic nervous system (increased TP and HF), at the background of a decrease in VLF observed only among Caucasians, which was associated with the lowest oxygen concentration in the exhaled air at the peak of the test. It was found that the significant differences in gas analysis identified at rest and at the peak of the test as well as rearrangements of the heart rate and cardiovascular system characteristics in response to the re-breathing in the young subjects residing in different regions of northeast Russia and belonging to different ethnic groups can serve as informative criteria reflecting the region caused ethnic characteristics of the organism. Conclusion — It was found, the most visible and informative parameters for the differences in dynamics of the studied systems demonstrated by the subjects of the two ethnic groups in the two observed regions of the Far East in response to a hypoxic-hypercapnic test with return breathing have been the spectral characteristics of the heart rate (TP, HF, VLF) and gas analysis with the calculation of the difference between the baseline and the peak values (difference in the CO2 and O2 concentration of the test-baseline).

ЭЛЕКТРОКАРДИОГРАФИЯ У КРЫС В ЭКСПЕРИМЕНТАЛЬНЫХ ИССЛЕДОВАНИЯХ (ОБЗОР ЛИТЕРАТУРЫ)

A scientific and analytical review of experimental research with the use of rats as biological test systems and electrocardiogram (ECG) parameters assessment was conducted. The data on various methods of ECG recording in anesthetized and unanesthetized animals (including the advantages and drawbacks of such methods) were presented. Both invasive and non-invasive approaches to recording the cardiac electrical activity in unanesthetized rats (including the method of telemetric ECG monitoring), which allow EEG monitoring in freely-behaving animals, were described. The review widely presents the studies with ECG registration in anesthetized animals. The data on influence of various types of anesthesia on electrical manifestation of cardiac activity in rats as well as hemodynamic parameters and activity of the vegetative centers regulating them was systematized. The review analyzes the parameters of rat’s ECG recorded in experimental studies in comparison with the parameters of human’s ECG and assesses the possibilities of extrapolating the data obtained to humans. The literature data analysis revealed a fairly wide range of scientific studies and preclinical trials of drugs based on the use of the electrocardiography method in rats. The most significant ECG parameters in rats were identified: PR interval, QRS complex (RS or Rs), T wave amplitude and corrected QT interval, which are of practical importance for adequate interpretation of the data of experimental research of integral characteristics of cardiovascular system and intersystem regulatory mechanisms activity.

Применение параллельных алгоритмов при численном моделировании кровотока в квазиодномерном приближении

The main goal of modern hemodynamic simulation is the prediction of blood pressure in the arteries, as well as the study of the various factors complex effect on the cardiovascular system characteristics. Quasi-one dimensional models of blood flow through blood vessels are the most popular. They allow to model the blood flow in the entire vascular system. Since full-scale simulation of the cardiovascular system requires large computational costs, the problem of parallelizing computation is actual. In this paper, the efficiency study was carried out for parallel algorithms in the numerical simulation of blood flow in the quasi-one-dimensional approximation. For simplicity, we consider the problem of the blood flow simulation in a separate blood vessel. When constructing a parallel algorithm, the domain decomposition method was applied. In each subdomain, the problem at each time step splits into a hyperbolic and parabolic subproblems. To solve the hyperbolic subtask, an integro-interpolation method based on the MUSCL scheme is used. To integrate over time, the second order Runge-Kutta and Adams-Bashfort methods are applied. The Crank-Nicholson method is used to solve the parabolic subproblem. At the subdomains conjunctions, the interface conditions are non-linear systems with three unknowns. These systems are solved using the Newton method. The time-cost structure was obtained for solving the test problem in a serial mode using the AMD CodeAnalyst profiler. Computations were carried out at the cluster of the BMSTU "Applied Mathematics" FN-2 department. The computational results showed that the time gain achieved by using the MPI library does not exceed a few percent in comparison with the OpenMP technology usage. Taking into account the simplicity of parallelizing algorithms through OpenMP, we can choose this technology, but MPI usage allows to make the software package universal (it can work both on shared memory systems and on distributed memory systems).