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Oetrended fluctuation analysis (DFA), a fractal analysis method which is widely used in heart rate variability (HRV) studies, is used to analyze the scaling behaviour of RR interval series of preterm neonates. The average scaling behaviour, calculated using 30000 RR intervals (3-4 hours), is characterized by a scaling exponent of 1.4 plusmn 0.1 at small scales (n<20) and a smaller exponent of 1...
This study describes the autonomic nervous system (ANS) response before, during and after a percutaneous transluminal coronary angioplasty (PTCA). The study population consisted of 37 patients undergoing PTCA from Staff-3 Database. Classical heart rate variability (HRV) parameters: RR mean, SD, rMSSD, LF, HF, LF/HF and LF/(HF+LF) were extracted and a multiple factorial analysis (MFA) was carried out...
This paper proposes to use the pulse transit time variability (PTTV) as an indicator of the variability in hemodynamics and studies its correlation with other cardiovascular variabilities, especially the blood pressure variability (BPV), which receives increasing attentions as an independent indicator of autonomic regulation and abnormalities in cardiovascular system. Continuous blood pressure (BP),...
On the body surface the electric field generated by the cardiac muscles consists of electric potential maxima and minima that increase and decrease during each cardiac cycle. The recording of these electric potentials as a function of time is called electrocardiography, and the resulting signal is called the electrocardiogram (ECG). The ECG signal is used extensively as a low cost diagnostic tool...
Spectral analysis was carried out on the R-wave attenuation (RWA) trend and heart rate variability (HRV) series, derived from the polysomnographic electrocardiogram (ECG) of the subjects with and without Cheyne Stokes breathing. Nocturnal polysomnography was performed on 16 normal subjects and 7 subjects with Cheyne Stokes breathing (CSB) patients. The polysomnographic ECG data was divided into fifteen...
With the evolution of m-Health, an increasing number of biomedical sensors will be worn on or implanted in an individual in the future for the monitoring, diagnosis, and treatment of diseases. For the optimization of resources, it is therefore necessary to investigate how to interconnect these sensors in a wireless body area network, wherein security of private data transmission is always a major...
Very slow yogic breathing techniques provide valuable insights into mechanisms of autonomous nervous system regulation that are usually not available for human subjects. This paper presents results of eight sessions of Nadi Shodhana Pranayama practiced at rate of one breath per minute. We characterized statistic and spectral measures of heart rate variability before, during, and after exercises. Significant...
Modern wireless communication technologies offer new possibilities for patient monitoring in hospitals, as well as at home or in outdoor environments. In this paper, we present a wireless system for ECG recordings and real-time analysis of heart rate variability (HRV). The system also makes it possible for distance consultation, for example with a specialist in cardiology, with the help of a WEB-solution
The goal of this work was to apply a time-varying spectral approach to study the dynamic changes in heart rate variability (HRV) produced by the arousal from sleep in obese patients with and without obstructive sleep apnea (OSA). We studied 10 subjects, group I without OSA and group II with OSA diagnostic. RR intervals series was obtained from ECG records. HRV spectral indexes (HF & LF component)...
Using a Volterra-Wiener model and the Laguerre expansion technique, we estimated in a previous study the parameters that characterize linear and the second order effects of respiration ("RSA") and arterial blood pressure ("ABR") on heart rate. RSA and ABR gains were significantly lower in obstructive sleep apnea (OSA) patients than in normal subjects. During sleep, ABR gain increased...
Past neuroimaging studies of acupuncture have demonstrated variable results for important brainstem nuclei. We have employed cardiac-gated fMRI with T1-variability correction to study the processing of acupuncture by the human brain. Furthermore, our imaging experiments collected simultaneous ECG data in order to correlate heart rate variability (HRV) with fMRI signal intensity. Subjects experienced...
A study of nonlinear dynamics of the heart rate variability (HRV) was performed using hidden Markov models (HMM) and mutual information (Ml). A methodology based on HMM has been developed in the present work. Cardiac RR series were analyzed in the three frequency bands: HF (0.15-0.45 Hz), high frequency band; LF (0.04-0.15 Hz), low frequency band; VLF (0.003-0.04 Hz), very low frequency band. These...
The purpose of this paper is to estimate emotions using neural network and the changes in activities of autonomic nervous system (ANS). Since ANS cannot be controlled artificially, we presumed that the changes in emotions would be reflected to the changes in ANS. In order to observe those changes, we provided the subjects with some video clips which can induce a variety of emotions and measured the...
Independent component analysis (ICA) and neural networks were used to extract sub-signals of heart rate variability (HRV). Electrocardiogram (ECG) recording was consisted of six minutes when the volunteer was lying and another six minutes when the volunteer was standing. HRV was extracted from ECG. According to time-delay, HRV was divided into five groups as mixed signals. ICA and neural networks...
In the Eastern Alps in Europe, the Dachstein massif with a height of almost 3000 m is an ideal location for investigating the effects of changes in altitude on the human body. Within a few minutes, a cable car facilitates an ascent from 1702 m to 2700 m above sea level, where the partial pressure of oxygen is about 550 mmHg (as compared to 760 mmHg at sea level). In this study ten healthy subjects...
The analysis of heart rate variability (HRV) has become a tool for noninvasively detecting the cardiovascular modulation of autonomic nervous system (ANS). Traditional analysis in frequency-domain mainly includes calculating the power and the peak frequency of each physiological frequency component. Whether employing the non-parametric or parametric method to estimate the power spectrum density (PSD),...
LifeWave energy patches are novel nanoscale semiconducting biomolecular antennas, that when placed in the oscillating bioelectromagnetic field of the body, resonate at frequencies in unison with certain biomolecules in the cells and signal specific metabolic pathways to accelerate fat metabolism. As a consequence of accelerated fat burning more cellular energy becomes readily available to support...
Heart rate variability (HRV) studies have shown that beat-to-beat interval variability is a strong indicator of a number of medical conditions, including heart failure, diabetes, and hypertension. Current HRV systems typically analyze pre-recorded high resolution ECG recordings. We have demonstrated an analog signal processing circuit which extracts real-time HRV data from EGC signals producing a...
The aim of the present study was to investigate the possible hypnotizability-related modulation of heart activity during nociceptive stimulation (pressor pain) and during nociceptive stimulation associated with the suggestion of analgesia in not hypnotized healthy individuals with a high (Highs) and a low (Lows) hypnotic susceptibility. ECG and respirogram were recorded. Standard time and frequency...
Our previous study showed that chronic vagal stimulation (VS) prevented the cardiac remodeling and improved the prognosis of chronic heart failure (CHF) rats after large myocardial infarction (MI). Antiarrhythmic effects of VS were assumed to produce such a beneficial outcome. Therefore, we examined the effects of VS on cardiac arrhythmias. The ECG transmitter and a radio-controlled stimulator were...
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