scholarly journals CHARACTERISTICS OF INDICATORS OF CENTRAL HEMODYNAMICS OF CADETS OF MARINE UNIVERSITY IN THE PERIOD OF LONG SWIMMING

2021 ◽  
Vol 7 (1) ◽  
pp. 54-59
Author(s):  
A. B. Gudkov ◽  
A. F. Shcherbina ◽  
O. N. Popova ◽  
A. N. Nikanov
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiovascular System ◽  
Contractile Function ◽  
Statistical Processing ◽  
Central Hemodynamics ◽  
The Third ◽  
Adaptive Mechanisms ◽  
Myocardial Contractile ◽  
Spss Software

Goal. To reveal the peculiarities of central hemodynamics of cadets of a marine university in the conditions of a five-month sailing.Materials and methods. A survey of 70 cadets on board of a sailing training vessel was carried out in the dynamics of a five-month voyage (165 days). Hemodynamic indicators were monitored before entry on duty. For the statistical processing of the results, the SPSS software, v 17.0 (IBM) was used.Results and its discussion. The first two months are characterized by stable indicators of myocardial contractile function, which begins to change from the third month. In the third month, signs of mobilization of the circulatory function appear, which is expressed in an increase in blood pressure (p<0.05) and blood pressure (p<0,05) (by 6.6% and 14%, respectively).The fourth and fifth months are characterized by a further activation of the compensatory-adaptive mechanisms of hemodynamics: an increase in blood pressure (p<0,05), blood pressure (p<0,001), as well as MVC (p<0,05) due to an increase in heart rate (p<0,001), which indirectly indicates a decrease in efficiency in the work of the cardiovascular system.

Bifurcation in a Simple Model of the Cardiovascular System

2000 ◽  
Vol 39 (02) ◽  
pp. 118-121 ◽  
Author(s):  
S. Akselrod ◽  
S. Eyal
Keyword(s):  
Nonlinear Dynamics ◽  
Blood Pressure ◽  
Heart Rate ◽  
Fixed Point ◽  
Cardiovascular System ◽  
Modified Model ◽  
Mayer Waves ◽  
Sustained Oscillations ◽  
Human Cardiovascular System ◽  
Physiological Values

Abstract:A simple nonlinear beat-to-beat model of the human cardiovascular system has been studied. The model, introduced by DeBoer et al. was a simplified linearized version. We present a modified model which allows to investigate the nonlinear dynamics of the cardiovascular system. We found that an increase in the -sympathetic gain, via a Hopf bifurcation, leads to sustained oscillations both in heart rate and blood pressure variables at about 0.1 Hz (Mayer waves). Similar oscillations were observed when increasing the -sympathetic gain or decreasing the vagal gain. Further changes of the gains, even beyond reasonable physiological values, did not reveal another bifurcation. The dynamics observed were thus either fixed point or limit cycle. Introducing respiration into the model showed entrainment between the respiration frequency and the Mayer waves.

Cardiovascular Responses to Muscle Stretching: A Systematic Review and Meta-analysis

2021 ◽  
Author(s):  
Ewan Thomas ◽  
Marianna Bellafiore ◽  
Ambra Gentile ◽  
Antonio Paoli ◽  
Antonio Palma ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiovascular System ◽  
Vascular Function ◽  
Meta Analysis ◽  
Random Effect ◽  
Cardiovascular Responses ◽  
Qualitative Description ◽  
Cross Sectional ◽  
Quantitative Synthesis

AbstractThe aim of this study will be to review the current body of literature to understand the effects of stretching on the responses of the cardiovascular system. A literature search was performed using the following databases: Scopus, NLM Pubmed and ScienceDirect. Studies regarding the effects of stretching on responses of the cardiovascular system were investigated. Outcomes regarded heart rate(HR), blood pressure, pulse wave velocity (PWV of which baPWV for brachial-ankle and cfPWV for carotid-femoral waveforms), heart rate variability and endothelial vascular function. Subsequently, the effects of each outcome were quantitatively synthetized using meta-analytic synthesis with random-effect models. A total of 16 studies were considered eligible and included in the quantitative synthesis. Groups were also stratified according to cross-sectional or longitudinal stretching interventions. Quality assessment through the NHLBI tools observed a “fair-to-good” quality of the studies. The meta-analytic synthesis showed a significant effect of d=0.38 concerning HR, d=2.04 regarding baPWV and d=0.46 for cfPWV. Stretching significantly reduces arterial stiffness and HR. The qualitative description of the studies was also supported by the meta-analytic synthesis. No adverse effects were reported, after stretching, in patients affected by cardiovascular disease on blood pressure. There is a lack of studies regarding vascular adaptations to stretching.

scholarly journals Rhythmic Breath Holding and Its Effect on Arterial Blood Pressure and Its Correlation With Blood Gases

2020 ◽  
Author(s):  
Bharti Bhandari ◽  
Manisha Mavai ◽  
Yogendra Raj Singh ◽  
Bharati Mehta ◽  
Omlata Bhagat
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiovascular System ◽  
Arterial Blood Pressure ◽  
Blood Gases ◽  
Total Power ◽  
Breath Holding ◽  
Single Episode ◽  
Arterial Blood ◽  
Maximum Inspiration

A single episode of breath-holding (BH) is known to elevate the blood pressure, and regular breathing exercise lowers the blood pressure. This prompted us to investigate how a series of BH epochs would affect the cardiovascular system. To observe arterial blood pressure (ABP) and heart rate (HR) changes associated with a series of “BH epochs” following maximum inspiration and maximum expiration and find the underlying mechanisms for the change by autonomic activity. Thirty-five healthy young adults were instructed to hold their breath repetitively, for 5 minutes, in two patterns, one following maximum inspiration and other following maximum expiration. ABP and ECG (for Heart Rate Variability) were continuously recorded at rest and during both the maneuvers. Capillary blood gases (BG) were zanalyzed at baseline and at the breakpoint of the last epoch of BH. ABP rose significantly at the breakpoint during both the maneuvers. No change in HR was observed. There was significant fall in PO2 from 94.7 (4.1) mmHg at baseline to 79.1 (9.0) mmHg during inspiratory and 76.90 (12.1) mmHg during expiratory BH. Similarly, SPO2 decreased from 96.3 (1.9) % at baseline to 95.4 (1.5) % and 94.5 (2.7) % during inspiratory and expiratory BH, respectively. Rise in PCO2 from 39.5(3.1) mmHg at baseline to 42.9 (2.7) mmHg and 42.1 (2.8) mmHg during inspiratory and expiratory BH respectively was observed. There was no significant correlation between blood gases and arterial blood pressure. Among HRV parameters, a significant decrease in SDNN, RMSSD, HFnu, total power and SD1/SD2 and the significant increase in LFnu, LF/HF and SD2 were observed during both BH patterns. Rhythmic BH patterns affect the cardiovascular system in similar way as a single episode of BH. Sympathetic overactivity could be the postulated mechanism for the same. © 2019 Tehran University of Medical Sciences. All rights reserved. Acta Med Iran 2019;57(8):492-498.

scholarly journals Predictors of the development of cardiac arrhythmias in women after induction of superovulation in vitro fertilization

2020 ◽  
Vol 10 (5) ◽  
pp. 57-65
Author(s):  
Victoria V. Vakareva ◽  
Marina V. Avdeeva ◽  
Larisa V. Scheglova ◽  
Sergey A. Bondarev ◽  
Pavel B. Voronkov
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiovascular System ◽  
Functional State ◽  
Blood Pressure Monitoring ◽  
Myocardial Oxygen Demand ◽  
Heart Rate Variability Analysis ◽  
Supraventricular Arrhythmias ◽  
Rate Profile

The article presents the results of a clinical and instrumental examination of 80 healthy women (average age 32,313,57 years) in order to assess the heart rhythm disturbances after induction of superovulation duringin vitrofertilization. All women were examined twice before and after induction of superovulation during extracorporeal fertilization. Clinical and instrumental examination included: electrocardiography at rest; echocardiography; 24-hour ECG monitoring with heart rate variability analysis; 24-hour blood pressure monitoring. Induction of superovulation is associated with a significant increase in mean daily HR max (р0,01), and consequently with an increase in myocardial oxygen demand. It has been established that induction of superovulation contributes to the development of supraventricular arrhythmias (р0,01) and an increase in episodes of apnea/hypnea (р0,01). Regression analysis revealed predictors of supraventricular arrhythmias after induction of superovulation, including adverse circadian heart rate profile, adverse circadian blood pressure profile, impaired autonomic regulation of heart activity (р0,01). It was shown that the appearance of rhythm disturbances is associated with both the initial functional state of the cardiovascular system and its response to the induction of superovulation. It was established a correlation between the estradiol concentration and the increase of daily average heart rate after induction of superovulation (r=0,30,р0,05), apnea/hypnea index after induction of superovulation (r=0,34,р0,05). Conclusion. Superovulation induction may exacerbate existing chronic cardiovascular diseases. Due to the adverse effect of superovulation induction on the daily heart rate profile, women need to evaluate the functional state of the cardiovascular system duringinvitrofertilization planning. This will prepare the woman for the upcoming procedure and avoid adverse reactions from the cardiovascular system in response to stimulation of superovulationin vitrofertilization.

In the Loop—Left Ventricular Pressures

2011 ◽  
pp. 42-47
Author(s):  
James R. Munis
Keyword(s):  
Heart Rate ◽  
Cardiac Output ◽  
Aortic Valve ◽  
Left Ventricle ◽  
Stroke Volume ◽  
Cardiovascular System ◽  
Aortic Root ◽  
Left Ventricular ◽  
Root Pressure ◽  
The Third

We've already looked at 2 types of pressure that affect physiology (atmospheric and hydrostatic pressure). Now let's consider the third: vascular pressures that result from mechanical events in the cardiovascular system. As you already know, cardiac output can be defined as the product of heart rate times stroke volume. Heart rate is self-explanatory. Stroke volume is determined by 3 factors—preload, afterload, and inotropy—and these determinants are in turn dependent on how the left ventricle handles pressure. In a pressure-volume loop, ‘afterload’ is represented by the pressure at the end of isovolumic contraction—just when the aortic valve opens (because the ventricular pressure is now higher than aortic root pressure). These loops not only are straightforward but are easier to construct just by thinking them through, rather than by memorization.

scholarly journals Assessment of the Functional State of the Cardiovascular System in Adolescents Living in the Southern Aral Sea Region

2021 ◽  
Vol 7 (9) ◽  
pp. 331-340
Author(s):  
K. Rozumbetov ◽  
S. Esemuratova ◽  
S. Nisanova ◽  
I. Nazhimov ◽  
A. Esimbetov ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Body Weight ◽  
Body Size ◽  
Cardiovascular System ◽  
Environmental Conditions ◽  
Harmful Effect ◽  
Aral Sea ◽  
Excess Body Weight ◽  
Total Body

According to studies conducted in recent years, there is a harmful effect of harmful chemicals in the environment on the cardiovascular system. The level of blood pressure is a very important hemodynamic indicator, the level of which provides primary information about diseases of the cardiovascular system. In this study, the indicators of total body size, blood pressure and heart rate were measured in adolescents living in unfavorable environmental conditions of the Aral Sea region. In adolescents of both sexes, body weight deficiency occupied a significant share. In girls and boys, the excess body weight was about 5%. Obesity was not observed in adolescents of both sexes. Hypotension was detected in 17.64% of the females studied by categories of systolic blood pressure, and there were no cases of hypertension among the females. And in males, hypotension of 8.70% and hypertension of 4.35% were observed. According to the categories of diastolic blood pressure, hypotension of 2.95% and hypertension of 8.82% were detected in females, hypotension of 8.69% and hypertension of 8.70% in males.

scholarly journals High salts intake, cardiovascular system and kidney in spontaneous hypertensive rats

2017 ◽  
Vol 16 (3) ◽  
pp. 62-69
Author(s):  
A. G. Kucher ◽  
O. N. Beresneva ◽  
M. M. Parastaeva ◽  
G. T. Ivanova ◽  
M. I. Zarajsky ◽  
...  
Keyword(s):  
Gene Expression ◽  
Blood Pressure ◽  
Heart Rate ◽  
Cardiovascular System ◽  
High Salt ◽  
Myocardial Remodeling ◽  
Hypertensive Rats ◽  
Relative Level ◽  
High Salt Diet ◽  
Salt Diet

Objective. To study the influence of diet containing high or normal NaCl on the arterial blood pressure level (BP), heart rate (HR), processes of myocardial remodeling and of nuclear transcription factor kB (NFkB) expression in myocardium and kidney in spontaneously hypertensive rats (SHR). Design and methods. The two groups of male SHRs received a diet with normal (0.34 %; n = 24, control) and high content of NaCl (8.0 %; n = 25; experimental group) for 2 months. Blood pressure (BP), heart rate (HR), cardiac left ventricular mass index (LVMI), left (LKMI) and right (RKMI) kidney mass indexes were determined. Morphological study of myocardium (light microscopy), including quantitative morphometry was carried out. In part of animals the relative level of NFkB gene expression in heart and kidney tissues was studied. Results and discussion. In rats fed a diet containing 8 % NaCl BP and HR did not change significantly compared with the control. However, LVMI, RKMI, LKMI were significantly higher in high-salt diet-treated animals than in controls. The heart of high-salt diet-treated animals developed the changes leading to hypertrophy and possibly hyperplasia of cardiomyocytes. In these animals, perivascular fibrosis, significant increase of arterial wall thickness and vacuolization of smooth muscle cells were revealed. The relative level of NFKB gene expression in rats receiving high-salt diet was 33-fold higher in myocardium and 12-fold higher in kidneys than in animals fed a normal salt diet. Conclusion. The high-salt diet is not necessarily accompanied by an increase in blood pressure, but causes myocardial remodeling, apparently due to direct «toxic» effects. The negative impact on the cardiovascular system of high-salt diet is in part mediated through NFkB-associated signaling pathways. Furthermore, high NaCl diet causes activation of NFkB in the kidneys.

scholarly journals The ocular cardiac reflex effect study on cardiac hemodynamic parameters in healthy young mans.

2019 ◽  
Vol 40 (1) ◽  
pp. 17-24
Author(s):  
A. I. Palamarchuk
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Flow ◽  
Cardiovascular System ◽  
Peripheral Resistance ◽  
Blood Flow Rate ◽  
Effect Study ◽  
Nonlinear Dependence ◽  
System Response ◽  
Hemodynamic Parameters

Purpose of the study. Investigate changes of cardiac hemodynamic parameters caused by ocular cardiac reflex triggering in healthy men’s in youthful age.Material and methods. 120 healthy male volunteers in youthful age were examined. The mean age was (19,2 ± 0,93 years). For ocular-cardiac reflex (OCR) triggering we used a patented model «Device for dosed compression effects on the eyeballs» and «The method of ocular cardiac reflex triggering». On the basis of the obtained parameters of systolic (SBP) and diastolic (DBP) blood pressure, by arithmetic operations, pulse pressure (PP) and average flow pressure (AFP) and integrative parameters of cardiohemodynamics (CHD) – systolic blood volume (SBV), minute blood flow volume (MBFV), volumetric blood flow rate (V), total peripheral resistance (TPR) were determined. Results. Three main types of cardiovascular system response on OCR triggering were identified. The first type – hypertensive (n = 30 (25%) of the total number of examined subjects) was characterized by a significant (p < 0,05) increase in heart rate, SBP, DBP, PP, AFP and other integrative parameters of CHD. The second, hypotonic type of the response (62 subjects; 51,7%) was characterized by a significant (p < 0,05) decrease in SBP, DBP, PP, AFP. Patients with third, dystonic type, of response (n = 28 (23,3%) of the total number examined subjects) showed significant bilateral changes of blood pressure parameters in a nonlinear dependence of compression power on the eyeballs. Determination CHD parameters directly after and 3 and 5 minutes after decompression of the air in the compression device we enabled to determine the subtype of the mobility of the nervous centers as a feature that complements the basic type. The subtype of normal mobility was revealed in 63,3% (n = 19) of subjects with the main hypertensive type of response, 69,3% (n = 43) of subjects with the main hypotonic and 60,7 % (n = 17) with the main dystonic type of response of the cardiovascular system. The inert subtype in the mobility of the cardiovascular system were identified in 36,7% (n = 11) individuals with hypertension is the main type of response, at 30,7% (n = 19) of individuals with primary hypotonic type of response and 39,3 % (n = 11) – distancing. The obtained typological changes in blood pressure parameters caused by OCR triggering allowed to reveal predisposition to hypertension, hypotension, dystonia and to predict the development of hypertension in patients with hypertensive type of response usin appropriate primary prevention changes in life style. The highest risk of hypertension development may be in persons with hypertensive inert type of reaction of the system of regulation of blood pressure on OCR triggering. Further studies are being conducted to confirm this assumption. Keywords: oculo-cardiac reflex, blood pressure, heart rate, young age.

scholarly journals Comparative characteristics of changes in central hemodynamics during early recovery after different exercise regimes

2021 ◽  
Vol 27 (2) ◽  
pp. 47-52
Author(s):  
H.V. Lukyantseva ◽  
O.M. Bakunovsky ◽  
S.S. Malyuga ◽  
T.M. Oliinyk ◽  
N.R. Manchenko ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Cardiovascular System ◽  
Dynamic Loading ◽  
Vascular Resistance ◽  
Dynamic Load ◽  
Static Loading ◽  
Circulatory System ◽  
The Body ◽  
Central Hemodynamics ◽  
Early Recovery

The cardiovascular system is one of the most important functional systems of the body, which determine the level of physical performance of the body. Insufficient study of the response of the circulatory system to the combination of strength training with endurance exercises requires more detailed comparative studies of the impact of dynamic and static loads on the indicators of central hemodynamics. Accordingly, the aim of our study was to study the characteristics of the reaction of the cardiovascular system in the period of early recovery after dosed exercise of a dynamic and static nature. The study examined the response of the central hemodynamics of young men in the period of early recovery after dynamic loading (Martine functional test) and static loading (holding on the stand dynamometer DS-200 force with a power of 50% of maximum standing force). The change in circulatory system parameters was recorded using a tetrapolar thoracic impedance rheoplethysmogram on a computerized diagnostic complex “Cardio +”. It is established that the dynamic load in the period of early recovery does not cause a significant positive chronotropic effect, leads to a decrease in vascular resistance of blood flow, to an increase in pulse blood pressure. The increase in cardiac output is mainly due to the increase in stroke volume, which indicates a fairly high functional reserves of the heart. It is revealed that under conditions of static loading the reaction of central hemodynamics and the course of early recovery are radically different from the changes of indicators under dynamic loading. In persons with a normodynamic type of reaction to dynamic load, there are no significant changes in the minute volume of blood at a similar volume of active muscle mass static load. Meeting the metabolic needs of working skeletal muscles and compensating for the oxygen debt is realized by increasing the total peripheral vascular resistance and increasing systolic blood pressure in the postpartum period. The physiological meaning of this phenomenon is to maintain a sufficient level of venous return of blood to ensure the pumping function of the heart.

Hemodynamics in awake rabbits during hyperbaric helium-oxygen exposure

1980 ◽  
Vol 48 (2) ◽  
pp. 281-283 ◽  
Author(s):  
L. E. Boerboom ◽  
J. N. Boelkins
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Flow ◽  
Cardiac Output ◽  
Cardiovascular System ◽  
Systemic Vascular Resistance ◽  
Elevated Pressure ◽  
Inert Gases ◽  
Gas Mixture ◽  
Organ Blood Flow

Although man is being exposed to hyperbaric environments more frequently, the effects of these environments and the inert gases used are not clearly defined. We therefore designed an experiment to examine both the effects of helium and elevated pressure on the cardiovascular system in conscious rabbits exposed to normoxic levels of a helium-oxygen (He-O2) gas mixture at 1 and 11 atmospheres absolute (ATA) for 2 h. Variables studied included heart rate, blood pressure, cardiac output, systemic vascular resistance, organ blood flow, and resistance to flow. The only change observed was a decrease in heart rate from a control of 284 +/- 7 (mean +/- SE) to 246 +/- 12 beats/min after 2 h of breathing He-O2 at 1 ATA. We therefore conclude that the cardiovascular system is not adversely affected by helium or elevated pressure as used in this experiment.

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