Гендерные особенности связанности низкочастотных колебаний в вегетативной регуляции кровообращения у пациентов c перенесенным инфарктом миокарда

Background:This is the first randomised controlled trial to assess the impact of unsupervised high-intensity interval training on cardiovascular autonomic function in adults with type 2 diabetes.Methods:A total of 22 individuals with type 2 diabetes (age 60 ± 2 years, 17 males) lay in a supine position for 20 min for evaluation of cardiovascular autonomic function, which included (1) time domain measures of heart rate variability, (2) frequency domain measures of heart rate variability and blood pressure variability and (3) baroreflex receptor sensitivity. Participants were randomised into 12 weeks of high-intensity interval training (3 sessions/week) or standard care control group.Results:After 12 weeks, the between-group change in HbA1c (%) was significant (high-intensity interval training: 7.13 ± 0.31 to 6.87 ± 0.29 vs Control: 7.18 ± 0.17 to 7.36 ± 0.21, p = 0.03). There were no significant changes in measures of heart rate variability; R-R interval (ms) (high-intensity interval training: 954 ± 49 to 973 ± 53 vs Control: 920 ± 6 to 930 ± 32, p = 0.672), low frequency/high frequency (high-intensity interval training: 0.90 ± 0.21 to 0.73 ± 0.07 vs Control: 1.20 ± 0.29 to 1.00 ± 0.17, p = 0.203), or blood pressure variability; systolic blood pressure low frequency/high frequency (high-intensity interval training: 0.86 ± 0.21 to 0.73 ± 0.10 vs Control: 1.06 ± 0.26 to 0.91 ± 0.14, p = 0.169). At baseline, HbA1c was negatively correlated with baroreflex receptor sensitivity (r = –0.592, p < 0.01).Conclusion:High-intensity interval training improves glycaemic control but has limited effect on cardiovascular autonomic regulation in patients with type 2 diabetes.

An increased cardiovascular mortality up to three times higher than in general populations associated with an increased heart rate is reported in patients suffering from schizophrenia suggesting a cardiac autonomic dysregulation in schizophrenic patients. Mechanisms which could be responsible for this increased cardiovascular mortality are under debate (unhealthy lifestyle, smoking, diabetes, adverse pro-arrhythmic effects of antipsychotic medication, altered autonomic function). The aim of this study was to determine if medical treatment and/or schizophrenia itself causes cardiac autonomic dysregulation. We investigated 46 patients suffering from schizophrenia (acute non-mediated - G1, medicated - G2) and 23 matched (age, gender) healthy control subjects (CON). From every patient three times ECG and non-invasiv blood pressure were recorded. Cardiac autonomic regulation was evaluated by linear and non-linear (symbolic dynamics (JSD)) methods of heart rate variability (HRV), blood pressure variability (BPV) and baroreflex sensitivity (BRS). The results show that non-medicated schizophrenic patients differ significantly from CON (p<0.05) in linear and nonlinear measures. In the medicated state considerably high significant differences between schizophrenic patient and CON were found (p<0.0001). These results demonstrate that acute schizophrenia influences autonomic regulation significantly and that standard medical treatment with antipsychotics leads to an additional altered autonomic regulation in schizophrenia patients with suppressed HRV, BRS, JSD and increased BPV measures.Keywordsautonomic regulationschizophrenia

Simple SummaryObstructive sleep apnea (OSA) is associated with behavioral, cardiovascular, and metabolic dysfunction. Autonomic changes have also been described in patients with OSA. In this study, we measured the heart rate variability (HRV) on electrocardiogram (ECG) tracings of OSA patients as a measure of cardiac autonomic regulation and putative predictor of disturbed breathing during nighttime. Our findings confirm an altered cardiac autonomic regulation in OSA patients during nighttime and identify a possible role of nighttime HRV in predicting sleep breathing disorders.Obstructive sleep apnea (OSA) can have long-term cardiovascular and metabolic effects. The identification of OSA-related impairments would provide diagnostic and prognostic value. Heart rate variability (HRV) as a measure of cardiac autonomic regulation is a promising candidate marker of OSA and OSA-related conditions. We took advantage of the Physionet Apnea-ECG database for two purposes. First, we performed time- and frequency-domain analysis of nocturnal HRV on each recording of this database to evaluate the cardiac autonomic regulation in patients with nighttime sleep breathing disorders. Second, we conducted a logistic regression analysis (backward stepwise) to identify the HRV indices able to predict the apnea–hypopnea index (AHI) categories (i.e., “Severe OSA”, AHI ≥ 30; “Moderate-Mild OSA”, 5 ≥ AHI < 30; and “Normal”, AHI < 5). Compared to the “Normal”, the “Severe OSA” group showed lower high-frequency power in normalized units (HFnu) and higher low-frequency power in normalized units (LFnu). The standard deviation of normal R–R intervals (SDNN) and the root mean square of successive R–R interval differences (RMSSD) were independently associated with sleep-disordered breathing. Our findings suggest altered cardiac autonomic regulation with a reduced parasympathetic component in OSA patients and suggest a role of nighttime HRV in the characterization and identification of sleep breathing disorders.

Physical inactivity represents a major risk for cardiovascular disorders, such as hypertension, myocardial infarction or sudden death; however, underlying mechanisms are not clearly elucidated. Clinical and epidemiological investigations suggest, beyond molecular changes, the possibility of an induced impairment in autonomic cardiovascular regulation. However, this hypothesis has not been tested directly. Accordingly, we planned a study with noninvasive, minimally intrusive, techniques on healthy volunteers. Participants were maintained for 90 days strictly in bed, 24 h a day, in head-down (-6 degrees ) position (HDBR). Physical activity was thus virtually abolished for the entire period of HDBR. We examined efferent muscle sympathetic nerve activity, as a measure of vascular sympathetic control, baroreceptor reflex sensitivity, heart rate variability (assessing cardiovagal regulation), RR and systolic arterial pressure and low-frequency and high-frequency normalized components (as a window on central oscillatory regulation). Measures were obtained at rest and during simple maneuvers (moderate handgrip, lower body negative pressure and active standing) to assess potential changes in autonomic cardiovascular responsiveness to standard stimuli and the related oscillatory profiles. HDBR transiently reduced muscle sympathetic nerve activity, RR, heart rate variability and baroreceptor reflex sensitivity late during HDBR or early during the recovery phase. Conversely, oscillatory profiles of RR and systolic arterial pressure variability were maintained throughout. Responsiveness to test stimuli was also largely maintained. Prolonged inactivity as induced by HDBR in healthy volunteers reduces both cardiovagal and vascular sympathetic regulation, while largely maintaining peripheral responsiveness to standardized stimuli and sparing the functional structure of central oscillatory cardiovascular regulation.

Background and purposeWhite matter lesions (WMLs) are frequent in sickle cell disease (SCD), with a prevalence described to be as high as 53% by age 30. Cerebrovascular regulation and cardiovascular autonomic regulation, more specifically the sympatho‐vagal balance, can be altered in SCD. In this study the association between WMLs, cerebrovascular regulation and sympatho‐vagal balance was assessed in SCD patients.Methods and resultsSickle cell disease patients with no history of stroke were prospectively evaluated for cerebrovascular reactivity using the breath‐holding test (BHT), the sympatho‐vagal balance (ratio low frequency/high frequency [HF]) using heart rate variability parameters and cerebral autoregulation in the time domain using correlation index Mx, and arterial cerebral compliance based on continuous assessment of cerebral blood flow velocities using transcranial Doppler ultrasound and arterial blood pressure with photo‐plethysmography. WMLs were assessed with magnetic resonance imaging using Fazekas score grading and the presence of lacunes. Forty‐one patients (F/M 25/16) were included. Median age was 37.5 years (19–65). Twenty‐nine (70.7%) patients had SS genotype. Eleven patients had WMLs (26.8%). Patients with WMLs were significantly older (p < 0.001), had a lower HF (p < 0.005) and an impaired cerebral arterial compliance (p < 0.014). The receiver operating curve for the regression model including age and HF showed a higher area under the curve compared to age alone (0.946 vs. 0.876). BHT and Mx did not significantly differ between the two groups.ConclusionsLower parasympathetic activity and impaired cerebral arterial compliance were associated with WMLs in adults with SCD. This could potentially yield to a better understanding of pathophysiological parameters leading to premature cerebrovascular ageing in SCD.

Obese persons suffer from an increased mortality risk supposedly due to cardiovascular disorders related to either continuously lowered parasympathetic or altered sympathetic activation. Our cross-sectional correlation study establishes the relationship between obesity and autonomic regulation as well as salivary cortisol levels. Three patient cohorts were sampled, covering ranges of body mass index (BMI) of 27-32 (n=17), 33-39 (n=13) and above 40 kg/m(2)(n=12), and stratified for age, sex and menopausal status. Autonomic cardiovascular regulation was assessed by use of heart rate variability and continuous blood pressure recordings. Spectral analytical calculation (discrete Fourier transformation) yields indices of sympathetic and parasympathetic activation and baroreflex sensitivity. Morning salivary cortisol was concurrently collected. Contrary to expectation, BMI and waist/hip ratio (WHR) were inversely correlated with sympathetic activity. This was true for resting conditions (r=-0.48, P<0.001; r=-0.33, P<0.05 for BMI and WHR respectively) and for mental challenge (r=-0.42, P<0.01 for BMI). Resting baroreflex sensitivity was strongly related to the degree of obesity at rest (BMI: r=-0.35, P<0.05) and for mental challenge (r=-0.53, P<0.001). Salivary cortisol correlated significantly with waist circumference (r=-0.34, P=0.05). With increasing weight, no overstimulation was found but a depression in sympathetic and parasympathetic activity together with a significant reduction in baroreflex functioning and in salivary cortisol levels.

Introduction. Autonomic disorders in the form of autonomic neuropathy develop in vibration disease already at the early stages. As the disease progresses, the compensatory mechanisms of autonomic regulation are depleted, which leads to a worse prognosis for life and an increased risk of sudden cardiac death in patients with a severe degree of autonomic neuropathy. The aim of the study was to evaluate the severity of autonomic disorders and the preservation of compensatory reserves of autonomic regulation in patients with vibration disease. Materials and methods. One hundred thirty six miners with a proven diagnosis of vibration disease and 60 apparently healthy men of similar age without complaints and who had never worked under the conditions of exposure to industrial vibration were examined. Heart rate variability was analyzed at rest and during an active orthostatic test. Results. A decrease in the spectral parameters of heart rate variability in the patients with vibration disease was revealed. In a subgroup of the patients with an initially low level of very low frequency oscillations (less than 30 ms2/Hz), a decrease in the non-linear entropy index (less than 180) was determined; when performing an active orthostatic test, the power of very low frequency spectrum oscillations in the patients of this subgroup decreased by more than 50% of the initial values. In all patients with vibration disease under orthostatic load, a decrease in the oscillations of high and low frequencies of the spectrum of heart rate variability was revealed, whereas in the control group, the low frequency oscillation power remained at the initial level. Limitations. The study was limited to the evaluation of spectral and non-linear indices of heart rate variability in 136 miners with vibration disease. Conclusion. The criteria for a severe course of autonomic neuropathy in the patients with vibration disease were identified: an initial decrease in the power of very low frequency oscillations and a non-linear entropy index of heart rate variability, as well as a decrease in the power of very low frequency oscillations by more than 50% during an orthostatic test. According to these criteria, in 40.4% of the miners with vibration disease, pronounced violations of the autonomic support with a lack of compensatory mechanisms of autonomic regulation were found to be detected.

Racial and ethnic differences in cardiovascular morbidity and mortality persist despite advances in risk factor identification and implementation of evidence-based treatment strategies. African American men and women are disproportionately affected by cardiovascular risk factors, particularly hypertension. In this context, previous studies have identified sex and racial differences in autonomic cardiovascular regulation which may contribute to the development of hypertension and its high morbidity burden among African Americans. In this review, we provide a comprehensive evaluation of the potential pathophysiological mechanisms of blood pressure control and their differences based on sex and race. These mechanisms include obesity-induced sympathetic activation, sympatho-vascular transduction, baroreflex sensitivity and adrenoreceptor vascular sensitivity, which have been the subjects of prior investigation in this field. Understanding the racial differences in the pathophysiology of hypertension and its co-morbid conditions would allow us to implement better treatment strategies tailored to African Americans, with the ultimate goal of reducing cardiovascular mortality in this population.

The study investigated interactions between autonomic cardiovascular regulation and cortical activity. In 54 healthy subjects, baroreflex sensitivity (BRS) and respiratory sinus arrhythmia (RSA) were assessed at resting conditions. As an EEG indicator of cortical excitability, the contingent negative variation (CNV) was induced using a constant foreperiod reaction time task. At bivariate level, only RSA showed a moderate positive correlation with the CNV recorded at frontal electrodes. However, when common variance of BRS and RSA was controlled for in multiple regression analysis, an inverse association between BRS and the frontal CNV also arose. The inverse association between BRS and the CNV is discussed as reflecting bottom-up modulation of cortical excitability by baroreceptor afferents. The positive correlation between RSA and the CNV may relate to the interplay between prefrontal processing and cardiac vagal tone.

Introduction: Chronic stress in healthcare workers is associated with insomnia and risk for adverse health outcomes. High-resolution, relational, resonance-based, electroencephalic mirroring (HIRREM) is a noninvasive, closed-loop acoustic stimulation neurotechnology that identifies dominant brain frequencies and translates them into audible tones, to support auto-calibration and self-optimization of brain rhythms. Objective: We explore use of HIRREM in a cohort of healthcare workers enrolled in an IRB-approved open label feasibility study of HIRREM for diverse neuropsychological disorders. Methods: Twenty five employees (16 female), mean (SD) age 45.8 (13.9), received 14.8 (4.7) HIRREM sessions (90-120 minutes each) over 9.0 (3.6) days of in-office intervention. Data was collected before (V1), and 15.4 (11.7) days after completion (V2). Outcomes included BP and HR recordings for autonomic cardiovascular regulation (baroreflex sensitivity, BRS, and heart rate variability, HRV), with inventories for insomnia (ISI), depression (CES-D), traumatic stress (PCL-C), quality of life (EQ-5D global rating), and drop stick reaction testing (RXT). Paired t-tests were performed. Results: BRS and HRV (n=17) improved from V1 to V2, including Sequence ALL (+2.4 ms/mmHg (SE 2.8), p=0.15), SDNN (+8.9 ms (4.1), p=0.04), and rMSSD ms (+9.2 (4.9), p=0.07). There were significant improvements in symptoms and function at V2; ISI (n=25): -8 (5.3), p&lt;0.0001; CES-D (n=20): -7.3 (13.4), p=0.02; PCL-C (n=19): -12.1 (12.4); p&lt;0.001; EQ-5D (n=16): +10.8 (12.5), p&lt;0.01; RXT (n=18): -4.6 cm (5.5), p&lt;0.01. There were no serious adverse events. Conclusions: This exploratory study shows improved measures of cardiovascular regulation, and reduced insomnia, depression, and stress associated with use of HIRREM in a cohort of employees at an academic medical center. Data suggest that HIRREM is a promising intervention that merits further investigation to mitigate effects of chronic stress and improve wellness.

Effects of cardiac rehabilitation and exercise training on autonomic regulation in patients with coronary artery disease

Objective. To establish the types of autonomic regulation in patients with adolescent idiopathic scoliosis based on the analysis of heart rate variability at the preoperative stage. Material and Methods. The study included 69 adolescents with idiopathic scoliosis, who underwent cardiointervalogram recording with subsequent spectral analysis at rest and during an active orthostatic test in order to assess the reserves of autonomic regulation. Very low frequency oscillations of the spectrogram, stress index of regulatory systems, and the total power of the spectrum were analyzed. Four types of autonomic regulation were determined: type I with moderate predominance of sympathetic and central regulation, type II with pronounced predominance of sympathetic and central regulation, type III with moderate predominance of parasympathetic regulation, and type IV with pronounced predominance of parasympathetic regulation. Results. At rest, a moderate predominance of sympathetic activity and central regulation with moderate stress of regulatory systems, or type I regulation was observed in 15 (22%) patients; a sharp increase in the activity of central regulation with the development of a state of vegetative dysfunction, or type II regulation – in two (3%) patients; a moderate predominance of parasympathetic activity, or type III regulation – in 39 (56%) examined patients; and a pronounced predominance of parasympathetic regulation with overstrain of the regulatory systems, or type IV regulation – in 13 (19%) patients. After the orthostatic test, most of the examined patients, 44 (64%), had type I regulation, while type II was registered in seven (10%) patients, type III – in 14 (20%), and type IV – in four (6%) patients. Conclusion. The background state of autonomic regulation of the heart rate in most adolescents with idiopathic scoliosis reflects the stability of adaptation mechanisms. Orthostatic testing allows identifying cases of instability of regulatory system associated with the risk of hemodynamic instability due to the moderate predominance of sympathetic autonomic regulation observed in most patients.

Characteristics of Emotional Status and Autonomic Regulation in Patients with Ischemic Heart Disease and Sleep Disorders

Spectral analysis of heart rate and blood pressure variability in primary Sjögren's syndrome

Objective: To study the vegetative component of the pathogenesis of stress urinary incontinence in women and the dynamics of the autonomic nervous system parameters after a course of treatment, including myoelectric stimulation, extracorporeal magnetic stimulation and physiotherapy. Material and methods. The study included 90 women with stress urinary incontinence. All patients received standard drug therapy and were randomized into 4 groups: in the 1st group, patients additionally received myoelectric stimulation; in the 2nd — extracorporeal peripheral magnetic stimulation, in the 3rd — a complex effect of 9 myoelectric stimulation and electrical stimulation); the control group of patients additionally received a course of exercises according to A. Kegel. The state of the pelvic floor muscles was assessed according to perineometry data, the state of vegetative regulation in all patients according to the Kerdo index. Results. The study revealed that in the complex therapy group with a combination of EMS and extracorporeal magnetic therapy, the autonomic regulation indices tend to balance — eutonic reaction, which is much more effective in restoring the urinary retention function, and also significantly increases perineometry indices, compared with the indices in patients in the 1st and 2nd groups, as well as in the control group 4. Conclusion. The positive effect of electrical myostimulation can be explained by an increase in the activity of the striated muscles of the pelvic diaphragm and the sensitivity of nerve endings in the area of impact, which was confirmed by perineometry data. The effect of magnetic stimulation affected the change in the central regulation of autonomic tone in increasing the activity of the sympathetic division of the autonomic nervous system, which affected the activity of the smooth muscles of the bladder.