Values Of Heart Rate Variability Parameters Research Articles

Вариабельность сердечного ритма крыс-самок Вистар в условиях различной физической активности

Objective: to study the characteristics of heart rate variability in female Wistar rats under conditions of normal wakefulness, moderate physical activity and during recovery. Materials and methods. The study was carried out on 48 female Wistar rats aged 5-6 months. Heart rate variability (HRV) was recorded using Physiobelt 2.5.1 (Neurobotics, Russia). HRV analysis was performed using statistical, geometric, and spectral indicators. Physical activity was created using a two-minute treadmill run at a speed of 15 m/min at an angle of 15°. During the experiment we made 3 records of cardiosignal in each anumal: 1 - before the load, 2 - immediately after the load, 3 - after 15-minute rest. Results. Physical activity led to significant changes in a number of statistical and geometric indexes, but no differences in the spectral indexes of all the records were not found. In this regard, we performed cluster analysis on TP, HF, LF indexes of the record 1 that allowed us to form 2 groups: with low and high spectrum values (LSV and HSV). In each group, we observed significant changes in the values of HRV indexes between the records: in the group with LSV, physical activity led to a change in HR, RRNN, Mo, HF (ms2), LF (ms2, %), VLF (ms2, %), LF/HF, IC, in the group with HSV - HR, RRNN, Mo, Amo, IVR, PAPR, VLF (ms2), LF (%), IC. 15-minute recovery contributed to a further change in the value of HRV parameters. Conclusion. The results of the current study demonstrated that physical activity led to activation of the sympathetic nervous system, mobilization of neurohumoral regulation, as well as a change in the level of regulation of the cardiorhythm from peripheral to the central one. The analysis of HRV parameters in females with LSV and HSV allowed us to establish the features of neurohumoral regulation of the functional state of the organism in groups of animals initially different in spectral characteristics.

Alterations of Heart Rate Variability and Heart Rate Turbulence in Patients with Dilated Alcoholic and Non-alcoholic Cardiomyopathy

The aim of this study is to document the imbalance of the autonomic nervous system (ANS), expressed by heart rate variability (HRV) and heart rate turbulence (HRT), in patients with alcoholic cardiomyopathy (ACM) in comparison to those with idiopathic cardiomyopathy (ICM) and to evidence the existing differences regarding the long term evolution of these two subgroups. We studied HRV, in time and frequency domain, and HRT in 58 patients newly diagnosed with dilated cardiomyopathy (DCM), admitted between Mar 2015 and Dec 2017 for arrhythmias and/or acute congestive heart failure (CHF) in the Cardiology Clinic of our hospital. Depending on the aetiology of DCM, patients with no other obvious aetiology were assigned to two groups: A - ACM, with history of heavy alcohol consumption and B - with ICM. We performed 24 hours Holter monitoring in patients and controls. Regarding HRV parameters in time domain, they were significantly depressed in patients with ACM, comparing to those with ICM. Referring to HRT, all patients had abnormal, positive values of turbulence onset (TO) and we documented statistically significant differences (p<0.001) between the two groups. All patients had normal positive values of turbulence slope (TS). We documented, both in patients with ACM and ICM, depressed values of HRV parameters in time domain, as well as pathological values of TO. During follow-up, we noticed a significant difference between patients with ACM and ICM regarding the duration of hospitalization. Keywords: alcoholic cardiomyopathy, idiopathic cardiomyopathy, heart rhythm variability, heart rhythm turbulence

Influences of Thyroid Hormones on the Alteration of Autonomic Nervous System in Female Patients with Overt Hyperthyroidism

The aim of this study is to document the impact of thyroid hormones on the autonomic nervous system (ANS), expressed by heart rate variability (HRV) and heart rate turbulence (HRT), in patients with hyperthyroidism, compared to controls. Another purpose is to determine if HRV and HRT parameters are significantly correlated with the levels of thyroid hormones and the duration of hyperthyroidism. We studied HRV, in time and frequency domain, and HRT in a group of 113 premenopausal women, with still untreated overt hyperthyroidism, without cardiovascular diseases or risk factors for atherosclerosis, admitted between 2015 and 2018 in the Endocrinology Clinic of our hospital and compared the results with data obtained in 29 healthy controls. Depending on the severity and duration of hyperthyroidism and levels of thyroid hormones, patients were assigned to three groups: mild and moderate hyperthyroidism, severe and recurrent forms. We performed 24 hours Holter monitoring in patients and controls. Regarding HRV parameters in time domain, they were significantly depressed in patients comparing to controls. Referring to HRT, all patients had abnormal, positive values of turbulence onset (TO) and we documented statistically significant differences (p[0.001) when compared to controls. All patients had normal positive values of turbulence slope (TS), which decreased parallel with the severity of hyperthyroidism. In patients with hyperthyroidism, we documented depressed values of HRV parameters in time domain, correlated with the duration and severity of the thyroid disease. Our patients had pathologic values of TO. Although positive, TS values were lower when compared to controls.

HRV Analysis to Identify Stages of Home-based Telerehabilitation Exercise.

Spectral analysis of heart rate variability (HRV) has been widely used to investigate activity of autonomous nervous system. Previous studies demonstrated potential of analysis of short-term sequences of heart rate data in a time domain for continuous monitoring of levels of physiological stress however the value of HRV parameters in frequency domain for monitoring cycling exercise has not been established. The goal of this study was to assess whether HRV parameters in frequency domain differ depending on a stage of cycling exercise. We compared major HRV parameters in high, low and very low frequency ranges during rest, height of exercise, and recovery during cycling exercise. Our results indicated responsiveness of frequency-domain indices to different phases of cycling exercise program and their potential in monitoring autonomic balance and stress levels as a part of a tailored home-based telerehabilitation program.

Adrenergic urticaria and glossalgia induced by stress during dental therapy and monitored by heart rate variability analysis: A case report

This is the first case report that adrenergic urticaria and glossalgia were concurrently induced by stress during dental therapy, and non-invasively monitored by heart rate variability (HRV) analysis. The patient was a 53-year-old Japanese female. She was given the diagnosis of periodontitis, and had no previous history of systemic disease such as cardiovascular, respiratory, psychiatric, and allergic disease. In the course of the dental therapy, her blood pressure and heart rate were abnormally elevated; urticarias and glossalgia also developed. Furthermore, almost all parameters derived from HRV analysis changed with the intensity of loaded stress by the therapy. The appearance of these manifestations including the urticarias and the glossalgia closely correlated with the values of HRV parameters (notably LF noun, HF noun, and LF/HF) changing with the intensity of loaded stress by the therapy.

Re-innervation after heart transplantation: a multidisciplinary study

Several authors have demonstrated the existence and implications of re-innervation in the transplanted heart. Our aim was to study this phenomenon using 3 different techniques and to analyze the correlation among them. The study population consisted of 55 patients who had undergone heart transplantation 0.5 to 160 months earlier. We used a control group of 10 healthy individuals for comparison. To detect re-innervation, we used 1) planar and single photon emission computed tomography (SPECT) scintigraphic imaging of cardiac sympathetic activity with 123I-metaiodobenzylguanidine (MIBG), 2) analysis of heart-rate variability based on 24-hour Holter recordings; and 3) immunohistochemical study of endomyocardial biopsy specimens with anti-S100 antibody. The SPECT images showed evidence of sympathetic re-innervation in 17 patients (31%), predominantly in the anterior and in the septal regions of the left ventricle. Sympathetic activity increased during the post-transplant time course (r = 0.32; p = 0.017), although it did not reach normal values. We found a correlation between the low-frequency component of heart-rate variability (a marker of sympathetic activity) and the degree of MIBG uptake according to scintigraphy (r = 0.32; p = 0.015). Immunostaining study demonstrated the existence of nerve fibers in 36 patients (65%) who had greater values of heart-rate variability parameters reflecting parasympathetic activity. The 3 techniques evidenced re-innervation after heart transplantation. A correlation exists between sympathetic activity detected using MIBG scintigraphy and analysis of heart-rate variability. Patients in whom endomyocardial biopsy specimen reveals the presence of nerve fibers show more parasympathetic activity in the heart-rate variability analysis.