Regulation Of Heart Rate Research Articles

Parameters of the P300 auditory evoked potential and autonomic heart rate regulation in adolescents residing in different climatic and geographical conditions of Russia

BACKGROUND: The physiological functions and body development take place as the body adapts to the environment. For schoolchildren aged 16-17, their primary focus is on studying, which involves processing and retaining a significant volume of diverse information. The P300 auditory evoked potential reflects the neurophysiological aspects of cognitive functions such as attention and memory. This assessment is particularly relevant when considering the autonomic heart rate regulation in young individuals residing in the northern and southern regions of Russia.
 AIM: The objective of this study was to assess the auditory evoked potential components, namely P300 and N2, along with heart rate variability parameters in a group of healthy young Russian adolescents living in different climatic and geographical conditions.
 MATERIAL AND METHODS: The study sample consisted of 156 individuals aged 1617 years permanently residing in Arkhangelsk, Nadym and Simferopol. The assessment of the autonomic nervous system was carried out according to the parameters of heart rate variability on the agro-industrial complex Varikard. Registration of P300 and N2 components was carried out on the Neuron-Spectrum-4/VPM electroencephalograph (Neurosoft, Russia), using the oddball paradigm.
 RESULTS: The predominance of sympathetic nervous system activity in the regulation of heart rate and the lengthening of the N2 latency was revealed in adolescents in Nadym. In residents of Arkhangelsk and Simferopol, there were no differences in the parameters of heart rate variability and components of the auditory evoked potential of P300. Interhemispheric asymmetry of N2 latency was observed in young people of Arkhangelsk, where the time was shorter in the central (C4, p=0.04) and right anterior temporal (F8, p=0.01) sections.
 CONCLUSIONS: The imbalance in the autonomic nervous system towards the predominance of sympathetic influences in the heart rate regulation is reflected in slower recognition and differentiation of the sound signal.

The Heart-Brain Relationship :Cardio-Cerebral Axis

Cardiovascular and cerebral systems are integral components of the human body, each performing vital functions to ensure optimal physiological functioning. Recent advancements in medical research have shed light on the intricate interplay between the heart and the brain, revealing a complex web of interactions that go beyond traditional perspectives. Cardio-cerebral interactions refer to the dynamic and complex relationship between the cardiovascular and central nervous systems. The intricate interplay between the heart and the brain plays a pivotal role in maintaining homeostasis and ensuring optimal functioning of the entire organism. The autonomic nervous system, comprising the sympathetic and parasympathetic branches, plays a pivotal role in coordinating cardiovascular and cerebral activities. Sympathetic activation stimulates the release of norepinephrine, increasing heart rate and cardiac output. This response is closely linked to changes in cerebral blood flow, influencing cognitive functions such as attention and memory.The sympathetic and parasympathetic branches of the ANS play a crucial role in regulating heart rate, blood pressure, and cardiac output. Additionally, Neurotransmitters and hormones released by the cardiovascular and nervous systems further contribute to the intricate interplay.The interruption of blood flow to the brain not only results in acute neuronal injury but also triggers secondary mechanisms that may impact the heart, creating a cycle of cardio-cerebral dysfunction. Conversely, neurological disorders can influence cardiac function. Conditions such as autonomic dysregulation, epilepsy, and certain neurodegenerative diseases can impact the autonomic control of the heart, leading to arrhythmias, sudden cardiac death, and other cardiovascular complications.This essay aims to explore the multifaceted relationship between the cardiovascular and cerebral systems, emphasizing the bidirectional communication, shared regulatory mechanisms, and implications for overall health. The discussion delves into neuro-cardiology and brain science, offering insights into the underlying physiological processes and potential clinical applications. As research progresses, further insights into these mechanisms will undoubtedly pave the way for innovative therapeutic strategies that address both cardiovascular and neurological aspects of human health.Adopting a heart-healthy lifestyle, encompassing regular exercise, a balanced diet, and stress management, emerges as a key preventive strategy. These interventions not only promote cardiovascular health but also positively influence neuroplasticity and cognitive function.

The Essential Interconnection of the Reticular Formation, Intermediolateral Nucleus, and Hypothalamus-Pituitary-Adrenal Axis: A Comprehensive View on Cellular Homeostasis

This paper explores the hypothesis that the Intermediolateral Nucleus, by possessing a direct and unique connection with the adrenal medulla, stands in contrast to the two-neuron pathway typical of the Sympathetic Nervous System. This distinctive characteristic of the Intermediolateral Nucleus may play a crucial role in counter-entropic and cellular energy regulation. The Reticular Formation, extending from the brainstem to the start of the cervical spinal cord, is vital for the regulation of heart rate, breathing, and cognitive functions, facilitating continuous chemical interaction throughout the body and being pivotal for energy regulation. The Hypothalamic-Pituitary-Adrenal Axis, as the primary response mechanism to cellular challenges, holds a central role in energy regulation, countering entropic processes, and supporting vital bioenergetic complexities for survival. The intimate collaboration between the Reticular Formation, the Intermediolateral Nucleus, and the Hypothalamic-PituitaryAdrenal Axis is essential for the continuous process of adjustments and readaptations, enabling the organism to respond and adapt to constant changes in both internal and external environments. This study deepens our understanding of homeostasis and the synergistic interaction between these structures in the vital process of maintaining homeostasis and energy regulation.

Influential Factors in Intestinal Absorption and Renal Reabsorption of Calcium

Calcium is one of the vital and essential elements in the body, serving as a primary constituent of bones and teeth. It plays a fundamental role in nerve signal transmission, muscle contractions, heart rate regulation, blood clotting, energy production, glandular secretion, and immune system maintenance. Calcium is abundantly found in dietary sources, with most of it residing in the teeth and bones within the body. Approximately 40% of daily dietary calcium is absorbed primarily at the beginning of the intestine and before gastric juice neutralization, while 60% of it is excreted through feces. Calcium absorption occurs in two forms, passive and active, through the intestines, and renal reabsorption takes place through the kidneys. Various factors such as intestinal environment, dietary components (including lactose, proteins, and amino acids),bile salts, parathyroid hormone, vitamin D, acidic pH, health status, age, and growth hormone influence intestinal calcium absorption positively. Conversely, fatty acids, phytic acid, aging, alkaline pH, iron, magnesium, calcitonin hormones, and glucocorticoids reduce calcium absorption. Parathyroid hormone, calcitonin hormone, vitamin D, and dietary regimen significantly contribute to the active reabsorption of calcium through renal tubules. Despite the considerable variations in the calcium content of dietary sources, a highly precise regulatory system controls vitamin D production, preventing fluctuations in plasma calcium ion concentrations. This regulation helps prevent hypocalcemia and hypercalcemia, which can lead to numerous irregularities in the body.

Tilt table testing, methodology and practical insights for the clinic.

Tilt table testing (TTT) has been used for decades to study short-term blood pressure (BP) and heart rate regulation during orthostatic challenges. TTT provokes vasovagal reflex in many syncope patients as a background of widespread use. Despite the availability of evidence-based practice syncope guidelines, proper application and interpretation of TTT in the day-to-day care of syncope patients remain challenging. In this review, we offer practical information on what is needed to perform TTT, how results should be interpreted including the Vasovagal Syncope International Study classification, why syncope induction on TTT is necessary in patients with unexplained syncope and on indications for TTT in syncope patient care. The minimum requirements to perform TTT are a tilt table with an appropriate tilt-down time, a continuous beat-to-beat BP monitor with at least three electrocardiogram leads and trained staff. We emphasize that TTT remains a valuable asset that adds to history building but cannot replace it, and highlight the importance of recognition when TTT is abnormal even without syncope. Acknowledgement by the patient/eyewitness of the reproducibility of the induced attack is mandatory in concluding a diagnosis. TTT may be indicated when the initial syncope evaluation does not yield a certain, highly likely, or possible diagnosis, but raises clinical suspicion of (1) reflex syncope, (2) orthostatic hypotension (OH), (3) postural orthostatic tachycardia syndrome or (4) psychogenic pseudosyncope. A therapeutic indication for TTT in the patient with a certain, highly likely or possible diagnosis of reflex syncope, may be to educate patients on prodromes. In patients with reflex syncope with OH TTT can be therapeutic to recognize hypotensive symptoms causing near-syncope to perform physical countermanoeuvres for syncope prevention (biofeedback). Detection of hypotensive susceptibility requiring therapy is of special value.

Intersystem interactions of physiological system indicators in students with different types of autonomic regulation

Studying not only individual students indicators of students, but complex intersystem interactions that reflect the specifics of adaptive capabilities is of scientific interest. The aim of the study. To reveal the features of intersystem interactions of indicators of the blood vessels functional state, morphological and neurodynamic characteristics of students with different types of autonomic regulation, living in the KhantyMansiysk Autonomous Okrug – Yugra. Methods. 429 first–fourth-year students (348 girls, 80 boys) of the Surgut State Pedagogical University were examined. The initial type of autonomic regulation was determined by the average duration of electrocardiogram RR intervals. Anthropometry parameters (body length and weight) and body composition were assessed using Tanita BC-601 device (Tanita, Japan), vascular wall elasticity – using AngioScan-01 (AngioScan-Electronics Ltd, Russia), neurodynamic indicators – using NS-PsychoTest device (Neurosoft, Russia). Statistical analysis was carried out using Statistica 7.0 software (StatSoft Inc., USA). We used the nonparametric Mann – Whitney U-test to evaluate differences and the nonparametric Pearson R-test to analyze correlations. Results. An increase in the stiffness of the vascular wall of large and small arteries in girls is accompanied by an increase in parasympathetic activity. In young men, an increase in the stiffness of large arteries raises with an increase in sympathoadrenal activity, while a compensatory increase in the stiffness of small muscular arteries is noted with an increase in parasympathetic activity. In persons with the sympathicotonic type of autonomic regulation, an excess content of fat mass, an increased frequency of visceral obesity, and a deficiency in water content were registered. With the predominance of the parasympathetic component contribution to the regulation of cardiac rhythm, an increase in the processes of inhibition in the central nervous system was noted. In young men, reduced sensorimotor reactions are consistent with sympathetic activation in the regulation of heart rate. Correlation analysis made it possible to establish some features in the interaction of the vascular, morphological and central nervous systems. Conclusion. Differences in indicators of functional systems (physical development, blood flow, neurodynamic characteristics) in the examined groups of students are shown, taking into account gender and autonomic regulation type. Features of intersystem interactions of indicators of physiological systems of students’ bodies with different types of autonomic regulation were revealed.

Orthostatic Stress and Baroreflex Sensitivity: A Window into Autonomic Dysfunction in Lone Paroxysmal Atrial Fibrillation.

The abnormal neural control of atria has been considered one of the mechanisms of paroxysmal atrial fibrillation (PAF) pathogenesis. The baroreceptor reflex has an important role in cardiovascular regulation and may serve as an index of autonomic function. This study aimed to analyze the baroreceptor reflex's role in heart rate regulation during upright tilt (HUT) in patients with lone PAF. The study included 68 patients with lone PAF and 34 healthy individuals who underwent baroreflex assessment. Parameters such as baroreflex sensitivity (BRS), number of systolic blood pressure (BP) ramps, and the baroreflex effectiveness index (BEI) were evaluated. The study found that PAF patients had comparable resting BPs and heart rates (HRs) to healthy individuals. However, unlike healthy individuals, PAF patients showed a sustained increase in BP with an upright posture followed by the delayed activation of the baroreceptor function with a blunted HR response and lower BEI values. This indicates a pronounced baroreflex impairment in PAF patients, even at rest. Our data suggest that together with BRS, BEI could be used as a marker of autonomic dysfunction in PAF patients, making it important to further investigate its relationship with AF recurrence after ablation and its involvement in cardiovascular autonomic remodeling.

INDICATORS OF CIRCUITAL HEART RHYTHM IN SCHOOLCHILDREN WITH CARDIAC NEUROCERCULATORY DYSTONIA RESIDING IN THE ANDIJAN REGION

Annotation. According to the international systematization of diseases (10th revision), neurocirculatory dystonia (NCD) refers to somatoform autonomic dysfunction that occurs with a violation of the nervous regulation of the circulatory system. Among non-infectious diseases of childhood and adolescence, vegetative-vascular dystonia is considered the most common pathology with a frequency of 4.8 to 29.1%. It is known that vegetative-vascular dystonia or its variant neurocircular dystonia is considered a predictor of arterial hypertension, atherosclerosis and coronary heart disease at a young age. Currently, determination of heart rate variability (HRV) is recognized as the most informative non-invasive method for quantitative assessment of the autonomic regulation of heart rate. The purpose of the study was a comparative assessment of the variability of circadian rhythm and heart rate in adolescents with similar neurocirculatory dystonia living in urban and rural areas. Materials and methods. We examined 77 adolescents aged 12 to 17 years (average age 14.5±0.35 years, boys -31, girls -46), hospitalized with a diagnosis of somatoform autonomic dysfunction, cardiac type NCD, from January 2022 to February 2023. Information is classified by age and place of residence (urban, rural). Taking into account the mechanisms of development of the autonomic nervous system, 2 age groups were identified. 1st age group - children 12-14 years old 49.5±4.99% (average age 13.4±0.24 years), of which 62.5±8.83% lived in Andijan (group IA), 37.5±11.74% of adolescents - in rural areas of Andijan region (group IB). 2nd age group - teenagers 15-17 years old 50.5±4.99% (average age 16.5±0.29), of which 61.2±8.89% of young people lived in Andijan (group IIA), 38.8±11.49% - in rural areas (group IIB). All teenagers live in the Andijan region every day. Results. Among the examined adolescents with NCD of the heart, complaints of pain in the heart area were similar (in age group I - 70.8±6.56%, in age group II - in 83.7±5.28% of those examined). The pain was mostly temporary (lasting a few seconds) and stabbing in nature. Interruptions in heart function were noted by 43.8±7.16% of young people in group I and 55.1±7.11% of young people in age group II. In addition, 31.3±6.69% of adolescents in age group I and 36.7±6.89% of young people in group II complained of headache, dizziness, impotence, and excessive fatigue. Conclusions. When examining adolescents with neurocirculatory dystonia, it is necessary to conduct not only a normal ECG at rest, but also Holter ECG monitoring with determination of heart rate variability; the examination will ensure adequate treatment and monitoring of this group of patients. The detected changes in the circadian rhythm and rhythm variability in urban adolescents compared to rural ones are probably associated with living in an industrial zone, environmental criteria, nutrition, and an even greater information load, which urgently requires further research.

PDE4D mediates impaired β-adrenergic receptor signalling in the sinoatrial node in mice with hypertensive heart disease.

The sympathetic nervous system increases HR by activating β-adrenergic receptors (β-ARs) and increasing cAMP in sinoatrial node (SAN) myocytes while phosphodiesterases (PDEs) degrade cAMP. Chronotropic incompetence, the inability to regulate heart rate (HR) in response to sympathetic nervous system activation, is common in hypertensive heart disease; however, the basis for this is poorly understood. The objective of this study was to determine the mechanisms leading to chronotropic incompetence in mice with angiotensin II (AngII)-induced hypertensive heart disease. C57BL/6 mice were infused with saline or AngII (2.5 mg/kg/day for 3 weeks) to induce hypertensive heart disease. HR and SAN function in response to the β-AR agonist isoproterenol (ISO) were studied in vivo using telemetry and electrocardiography, in isolated atrial preparations using optical mapping, in isolated SAN myocytes using patch-clamping, and using molecular biology. AngII-infused mice had smaller increases in HR in response to physical activity and during acute ISO injection. Optical mapping of the SAN in AngII-infused mice demonstrated impaired increases in conduction velocity and altered conduction patterns in response to ISO. Spontaneous AP firing responses to ISO in isolated SAN myocytes from AngII-infused mice were impaired due to smaller increases in diastolic depolarization (DD) slope, hyperpolarization-activated current (If), and L-type Ca2+ current (ICa,L). These changes were due to increased localization of PDE4D surrounding β1- and β2-ARs in the SAN, increased SAN PDE4 activity, and reduced cAMP generation in response to ISO. Knockdown of PDE4D using a virus-delivered shRNA or inhibition of PDE4 with rolipram normalized SAN sensitivity to β-AR stimulation in AngII-infused mice. AngII-induced hypertensive heart disease results in impaired HR responses to β-AR stimulation due to up-regulation of PDE4D and reduced effects of cAMP on spontaneous AP firing in SAN myocytes.

Typological Features of Autonomic Heart Rate Regulation during Imitation of a Rise to Altitude by Using Additional Respiratory Resistance

Typological Features of Autonomic Heart Rate Regulation during Imitation of a Rise to Altitude by Using Additional Respiratory Resistance

The influence of insulin resistance variables on heart rate variability indices in mature men under Russia’s North conditions

BACKGROUND: Heart rate autonomic regulation can go out of balance which is normally assessed by the heart rate variability (HRV) indices. Similarly, it is relevant to research if and how HRV fluctuations can be influenced by varying signs of insulin resistance since they are quite common in Northern men. At present, there is no evidence of this influence in the North residents of older ages.AIM: This study aimed to comparatively assess heart rate variability in mature men who do or do not feature metabolic signs of insulin resistance.MATERIALS AND METHODS: Seventy-three mature aged male residents of Magadan Region, Caucasian by origin, were examined. All the subjects were divided into two groups: Group without insulin resistance signs (HOMA-IR index < 2.5 units) and Group with insulin resistance signs (HOMA-IR index > 2.5 units). We used immunochemiluminescent and enzymatic methods, and heart rate variability was assessed using the Varikard (Russia).RESULTS: Our research showed that 48% of all the examinees exhibited signs of insulin resistance along with an increase in the sympathetic activity in heart rate regulation. We also identified the heart rate indicators that had proved to undergo the most significant changes depending on the HOMA-IR index and the presence or absence of signs of insulin resistance: MxDMn, pNN50, SDNN, AMo50, SI, TP, HF, LF, and Body Mass.CONCLUSION: In general, the results obtained allow for ascertaining the high proportion of male Northerners of mature age with signs of insulin resistance. We also claim that those examinees demonstrate an autonomic imbalance and a moderate dominance of the sympathetic activity with a simultaneous decrease in activation of the parasympathetic link of autonomic nervous system and high body mass variables. At the same time, the correlations and causal associations among signs of insulin resistance, activation of the sympathetic link of autonomic nervous system, and overweight remain unclear. Apparently, all the analyzed features are likely to complement each other rather than completely exclude each other. The triad of obesity, signs of insulin resistance, and activation of the sympathetic link of autonomic nervous system is a driving factor for significant health risks. This study is expected to spread the use of the method of assessing heart rate variability based on insulin resistance signs as well as in reliance on metabolic disorders in general in a sample of mature men.

Formulation and Evaluation of Buccoadhesive Tablet of Verapamil Hydrochloride for the Treatment of Hypertension

The creation and assessment of buccoadhesive tablets of verapamil hydrochloride were the study's primary goals. Blood pushing excessively hard against the arterial wall is referred to as hypertension. Typically, hypertension is characterized by blood pressure readings over 140/90; readings over 180/120 are regarded as severe hypertension. Verapamil is used to manage angina (chest pain) and treat excessive blood pressure. Verapamil belongs to the category of drugs known as calcium channel blockers. In order to save the heart from having to pump as hard, it relaxes the blood artery. Additionally, it enhances the heart's blood and oxygen flow while decreasing electrical activity to regulate heart rate. Five formulations that demonstrated satisfactory physicochemical characteristics and drug release were chosen for the investigation. Physical examination, weight fluctuation, uniformity of content, thickness, friability, hardness, and in vitro drug release were used to characterize the formulation. In terms of physical examination, weight variation, uniformity of content, thickness, friability, hardness, and in vitro drug release, all formulations produce satisfactory results. The buccoadhesive tablet formulation (F2 Batch) had the best in vitro drug release of 87% in 8 hours. Verapamil hydrochloride's UV spectrum was examined, and it was discovered that the drug's highest absorbance occurs at 227nm, increasing its bioavailability.
 Keywords: Verapamil Hydrochloride, Hypertension, Bioavailability, Buccoadhesive Tablet, Calcium channel blocker.

Effect of hydrotherapy, balneotherapy, and spa therapy on blood pressure: a mini-review.

Hypertension (high blood pressure) is one of the most common health conditions. When your blood pressure is high for a long term, it can cause health problems, such as heart disease. In addition to the main methods of treatment, there are various methods of adjuvant therapy, one of the most common of which is hydrotherapy. In this review study, we examined the effects of hydrotherapy, balneotherapy, and spa therapy on blood pressure. We searched the PubMed/MEDLINE, Web of Science, Scopus, and Science Direct databases until April 2022 using related keywords. In summary, the current study shows that different hydrotherapy methods may improve blood pressure. Hydrotherapy as one of the adjunctive therapy methods can be effective in lowering blood pressure. Blood circulation is smoothed by the warmth of the water. This improvement may be achieved by regulating heart rate, releasing hormones that control blood pressure, or regulating the activity of baroreceptors or chemoreceptors. In addition to using medications, hypertension patients also use non-pharmacological approaches in their care, including hydrotherapy, balneotherapy, and warm water foot soaks performed at home. Although several lines of evidence show the potential effects of hydrotherapy, balneotherapy, and spa therapy on blood pressure, many clinical trials are needed.

Pathological Heart Rate Regulation in Apparently Healthy Individuals.

Cardiovascular diseases are the leading cause of morbidity and mortality in adults worldwide. There is one common pathophysiological aspect present in all cardiovascular diseases-dysfunctional heart rhythm regulation. Taking this aspect into consideration for cardiovascular risk predictions opens important research perspectives, allowing for the development of preventive treatment techniques. The aim of this study was to find out whether certain pathologically appearing signs in the heart rate variability (HRV) of an apparently healthy person, even with high HRV, can be defined as biomarkers for a disturbed cardiac regulation and whether this can be treated preventively by a drug-free method. This multi-phase study included 218 healthy subjects of either sex, who consecutively visited the physician at Gesundheit clinic because of arterial hypertension, depression, headache, psycho-emotional stress, extreme weakness, disturbed night sleep, heart palpitations, or chest pain. In study phase A, baseline measurement to identify individuals with cardiovascular risks was done. Therefore, standard HRV, as well as the new cardiorhythmogram (CRG) method, were applied to all subjects. The new CRG analysis used here is based on the recently introduced LF drops and HF counter-regulation. Regarding the mechanisms of why these appear in a steady-state cardiorhythmmogram, they represent non-linear event-based dynamical HRV biomarkers. The next phase of the study, phase B, tested whether the pathologically appearing signs identified via CRG in phase A could be clinically influenced by drug-free treatment. In order to validate the new CRG method, it was supported by non-linear HRV analysis in both phase A and in phase B. Out of 218 subjects, the pathologically appearing signs could be detected in 130 cases (60%), p < 0.01, by the new CRG method, and by the standard HRV analysis in 40 cases (18%), p < 0.05. Thus, the CRG method was able to detect 42% more cases with pathologically appearing cardiac regulation. In addition, the comparative CRG analysis before and after treatment showed that the pathologically appearing signs could be clinically influenced without the use of medication. After treatment, the risk group decreased eight-fold-from 130 people to 16 (p < 0.01). Therefore, progression of the detected pathological signs to structural cardiac pathology or arrhythmia could be prevented in most of the cases. However, in the remaining risk group of 16 apparently healthy subjects, 8 people died due to all-cause mortality. In contrast, no other subject in this study has died so far. The non-linear parameter which is able to quantify the changes in CRGs before versus after treatment is FWRENYI4 (symbolic dynamic feature); it decreased from 2.85 to 2.53 (p < 0.001). In summary, signs of pathological cardiac regulation can be identified by the CRG analysis of apparently healthy subjects in the early stages of development of cardiac pathology. Thus, our method offers a sensitive biomarker for cardiovascular risks. The latter can be influenced by non-drug treatments (acupuncture) to stop the progression into structural cardiac pathologies or arrhythmias in most but not all of the patients. Therefore, this could be a real and easy-to-use supplemental method, contributing to primary prevention in cardiology.

Modeling the clinical profile of patients with hypertension and atrial fibrillation by serum NTpro-BNP levels

Background. Hypertension and atrial fibrillation are a fairly common combination of heart pathology that occurs in the daily practice of a cardiologist. Associations of clinical laboratory and instrumental indicators with the levels of various biomarkers, in particular serum N-terminal fragment of brain natriuretic propeptide (NT-proBNP), are interesting and promising for scientific research and practical application. The aim of the study was to simulate the clinical profiles of patients with hypertension and atrial fibrillation depending on the serum levels of NTpro-BNP. Materials &amp; Methods. 89 patients with stage II hypertension and various clinical forms of atrial fibrillation were included in the study. All patients underwent a general clinical examination, additional determination of NT-proBNP serum levels, and assessment of quality of life according to the Minnesota Living with Heart Failure Questionnaire (MLHFQ) for 2–3 days of hospital stay at against the background of selection of optimal therapy. Sequential statistical processing of the obtained data using Spearman’s rank correlation analysis and multiple linear regression made it possible to create two clinical profiles of patients. Results &amp; conclusions. Thus, with a relatively high serum level of NTpro-BNP (≥810 ng/l), the following will be characteristic: hypertensive history &gt;12 years; the presence of signs of left ventricular hypertrophy on the ECG according to the Sokolov-Lyon criteria; increase in the right atrium &gt;36 mm and systolic pressure in the pulmonary artery &gt;38 mm Hg according to Echocardiography; an increase in the average daily heart rate &gt;110 per 1 min with Holter ECG monitoring; a decrease in the glomerular filtration rate &lt;56 ml/min/1.73m2 and an increase in the total MLHFQ score &gt;27. The dominant markers of a relatively high level of NTpro-BNP were a decrease in quality of life, instrumental signs of hemodynamic overload of the right heart and clinically significant cardiorenal disorders. With a relatively low serum level of NTpro-BNP (≤220 ng/l), the following will be characteristic: hypertensive history anamnesis &lt;8 years; lack of signs of the left ventricle hypertrophy on the ECG according to the Sokolov-Lyon criteria; the size of the right atrium &lt;34 mm and/or the value of systolic pressure in the pulmonary artery &lt;33 mm Hg according to Echocardiography; average daily heart rate with Holter ECG monitoring &lt;92 per 1 minute; glomerular filtration rate &gt;68 ml/min/1.73m2 and the total MLHFQ score &lt;21. The dominant markers of a relatively low level of NTpro-BNP were the absence of signs of left ventricular hypertrophy on the ECG and a balanced state of sympatho-adrenal activity by the nature of circadian regulation of heart rate. Keywords: atrial fibrillation; N-terminal fragment of brain natriuretic propeptide; clinical profile of patients.

Multifunctional changes in the athletes’ body during the formation of autonomic regulations’ overstrain under the influence of training load

Purpose: the purpose of this study was to generalize polysystemic changes that occur in the body of highly qualified athletes with signs of autonomic regulation overstrain under the influence of training load and during the recovery period after it. Material &amp; Methods: test subjects were qualified male athletes (N=202) aged 22.6±2.8 years, who were examined by means of spiroarteriocardiorhythmography (SACR) and computerized motion meter (CMM). In accordance with the design the examinations with the aid of SACR and CMM were carried out three times: in the morning, on an empty stomach, in a sitting position on the day of training (G1), immediately after training (during the first 5-7 minutes) (G2) and the next day in the morning after sleep (G3). Results: according to the data of the examination of athletes in the dynamics of recovery after the training load, options of changes in HRV indicators were determined, which indicated the formation of sympathetic and parasympathetic overstrain in athletes. Two groups were created. The first included 10 athletes, the second included 9 athletes. The analysis of changes in indicators, the research methods used, allowed us to establish differences in their dynamics during the formation of sympathetic and parasympathetic overstrain. Differences were noted among 18 indicators. Among them are indicators of HRV – ABI (c.u.), SRAI (c.u.), ARI (c.u.), RMSSD (ms), VLF (ms2), LFHF (ms2/ms2); variability of arterial pressure – LFSBPn (n.u.), HFSBPn (n.u.), LFHFSBP (mmHg2), TPDBP (mmHg2), LFDBP, (mmHg2), ICDBP (mmHg2/mmHg2); hemodynamics – CO (dm3), GPVR, (dyn/s/cm−5), CI (dm3/m2); respiratory variability – TPR (L×min–1)2; of sensorimotor function – SCSleft (s), SMleft (%). Conclusions: the obtained results on the formation of sympathetic and parasympathetic overstrain under the influence of intense physical activity indicate that changes in the autonomic regulation of the heart rate, which determine the type of heart rate regulation, are accompanied by a number of changes in hemodynamics, autonomic regulation of the pumping function of the heart, vascular tone, respiratory regulation, and sensorimotor function. The determined differential dynamics of changes in cardiorespiratory and sensorimotor indicators will allow further algorithmization of the assessment of the functional state of the athletes’ body in order to detect early states of non-functional overstrain and overtraining.

The Heart-Brain Relationship:Cardio-Cognitive axis

The bidirectional communication between the heart and the brain, often referred to as the cardio-cognitive axis, plays a pivotal role in maintaining homeostasis and influencing overall health. The physiological basis of cardio-cognitive interactions lies in the intricate network of neural and hormonal pathways that facilitate communication between the heart and the brain. The autonomic nervous system, comprising the sympathetic and parasympathetic branches, regulates heart rate, blood pressure, and vascular tone, exerting profound effects on cognitive processes. For instance, the sympathetic activation during a stressful situation triggers the release of catecholamines, influencing attention, memory, and decision-making. Furthermore, the heart's intrinsic nervous system, known as the cardiac plexus, contributes to this bidirectional communication. Studies have shown that the heart can send signals to the brain, modulating emotional processing and cognitive functions. The phenomenon of heart rate variability (HRV), an index of the beat-to-beat variation in heart rate, has emerged as a valuable marker of this interaction. High HRV is associated with better cognitive performance and emotional regulation, emphasizing the importance of a dynamically responsive cardiovascular system. Disruptions in the cardio-cognitive axis can have detrimental consequences. Cardiovascular diseases (CVDs), such as hypertension and atherosclerosis, are known to impact cognitive function. Moreover, conditions like heart failure and arrhythmias contribute to cerebral hypoperfusion, exacerbating the risk of cognitive decline and dementia. Neurotransmitters and hormones released by the cardiovascular system also impact cognitive processes. For instance, catecholamines released during stress, such as epinephrine and norepinephrine, can influence attention and memory. The intricate interdependence between cardiovascular health and cognitive function underscores the importance of a holistic approach to well-being. This essay has explored the neuroanatomical, physiological, and psychological aspects of cardio-cognitive interactions, emphasizing the bidirectional relationships that shape human health. Further research in this interdisciplinary field is essential for developing integrated interventions that target both cardiovascular and cognitive domains, promoting a comprehensive approach to health and longevity.

Core body temperature changes before sleep are associated with nocturnal heart rate variability.

Core body temperature (CBT) reductions occur before and during the sleep period, with the extent of presleep reductions corresponding to sleep onset and quality. Presleep reductions in CBT coincide with increased cardiac parasympathetic activity measured via heart rate variability (HRV), and while this appears to persist into the sleep period, individual differences in presleep CBT decline and nocturnal HRV remain unexplored. The purpose of the current study was to assess the relationship between individual differences in presleep CBT reductions and nocturnal heart rate (HR) and HRV in a population of 15 objectively poor sleeping adults [10 males, 5 females; age, 33 ± 4 yr; body mass index (BMI) 27 ± 1 kg/m2] with the hypothesis that blunted CBT rate of decline would be associated with elevated HR and reduced nocturnal HRV. Following an adaptation night, all participants underwent an overnight, in-laboratory sleep study with simultaneous recording of polysomnographic sleep including electrocardiography (ECG) and CBT recording. Correlations between CBT rate of change before sleep and nocturnal HRV were assessed. Blunted rate of CBT decline was significantly associated with increased heart rate (HR) in stage 2 (N2; R = 0.754, P = 0.001), stage 3 (N3; R = 0.748, P = 0.001), and rapid-eye movement (REM; R = 0.735, P = 0.002). Similarly, blunted rate of CBT decline before sleep was associated with reduced HRV across sleep stages. These findings indicate a relationship between individual differences in presleep thermoregulatory processes and nocturnal cardiac autonomic function in poor sleeping adults.NEW & NOTEWORTHY Core body temperature (CBT) reductions before sleep onset coincide with increases in heart rate variability (HRV) that persist throughout the sleep period. However, the relationship between individual differences in the efficiency of presleep core temperature regulation and nocturnal heart rate variability remains equivocal. The present study reports an association between the magnitude of presleep core body temperature changes and nocturnal parasympathetic activity, highlighting overlap between thermoregulatory processes before sleep and nocturnal cardiac autonomic function.

Genome-Wide Assessment of Runs of Homozygosity by Whole-Genome Sequencing in Diverse Horse Breeds Worldwide.

In the genomes of diploid organisms, runs of homozygosity (ROH), consecutive segments of homozygosity, are extended. ROH can be applied to evaluate the inbreeding situation of individuals without pedigree data and to detect selective signatures via ROH islands. We sequenced and analyzed data derived from the whole-genome sequencing of 97 horses, investigated the distribution of genome-wide ROH patterns, and calculated ROH-based inbreeding coefficients for 16 representative horse varieties from around the world. Our findings indicated that both ancient and recent inbreeding occurrences had varying degrees of impact on various horse breeds. However, recent inbreeding events were uncommon, particularly among indigenous horse breeds. Consequently, the ROH-based genomic inbreeding coefficient could aid in monitoring the level of inbreeding. Using the Thoroughbred population as a case study, we discovered 24 ROH islands containing 72 candidate genes associated with artificial selection traits. We found that the candidate genes in Thoroughbreds were involved in neurotransmission (CHRNA6, PRKN, and GRM1), muscle development (ADAMTS15 and QKI), positive regulation of heart rate and heart contraction (HEY2 and TRDN), regulation of insulin secretion (CACNA1S, KCNMB2, and KCNMB3), and spermatogenesis (JAM3, PACRG, and SPATA6L). Our findings provide insight into horse breed characteristics and future breeding strategies.

A Physiological Control for Artificial Heart Pump based on Adaptive Regulation of Heart Rate and the improved BAS Algorithm Optimization

In order to solve the problem that the traditional artificial heart pump has poor dynamic bionic performance and cannot respond to blood perfusion in real time according to the patient’s state, this paper proposes a new physiological control method based on adaptive adjustment of heart rate. Firstly, a coupled model of the cardiovascular circulatory system and artificial heart pump was established, and the correctness of the model is verified by hemodynamic simulation. Secondly, according to the model-free adaptive control theory, the artificial heart pump physiological control strategy for adaptive regulation of heart rate is designed, including pseudo partial derivative estimation algorithm and adaptive control law. Then, the parameters of the adaptive controller are optimized by the improved beetle antennae search algorithm. Finally, the auxiliary effect and dynamic performance of the adaptive control strategy are studied by numerical methods. The results show that the physiological control method based on adaptive regulation of heart rate realizes the adaptive modulation of heart rate and blood flow, which can meet the needs of blood perfusion in different states and help to promote the recovery of damaged heart.