Wyszukiwarka
Filtry
wszystkich: 2508
-
Katalog
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: heart rate variability
-
Partitioning total heart rate variability
Publikacja -
Ordinal pattern statistics for the assessment of heart rate variability
PublikacjaThe recognition of all main features of a healthy heart rhythm (the so-called sinus rhythm) is still one of the biggest challenges in contemporary cardiology. Recently the interesting physiological phenomenon of heart rate asymmetry has been observed. This phenomenon is related to unbalanced contributions of heart rate decelerations and accelerations to heart rate variability. In this paper we apply methods based on the concept...
-
Heart rate variability and functional outcome in ischemic stroke
Publikacja -
Persistent homology as a new method of the assessment of heart rate variability
PublikacjaHeart rate variability (hrv) is a physiological phenomenon of the variation in the length of the time interval between consecutive heartbeats. In many cases it could be an indicator of the development of pathological states. The classical approach to the analysis of hrv includes time domain methods and frequency domain methods. However, attempts are still being made to define new and more effective hrv assessment tools. Persistent...
-
Disentangling respiratory sinus arrhythmia in heart rate variability records
Publikacja -
Entropy measures of heart rate variability for short ECG datasets in patients with congestive heart failure
PublikacjaWe investigated the usefulness of entropy measures calculated for short ECG series in distinguishing healthy subjects from patients with congestive heart failure (CHF). Four entropy measures were tested: Approximate Entropy (ApEn), Sample Entropy (SampEn), Fuzzy Entropy (FuzzyEn) and Permutation Entropy (PE), each computed for ECG series of 1000, 500, 250 and 100 RR intervals. We found that with a reduction of the data set length...
-
Entropy Measures of heart rate variability for short ECG datasets in patients with congestive heart failure
PublikacjaWe investigated the usefulness of entropy measures calculated for short ECG series in distinguishing healthy subjects from patients with congestive heart failure (CHF). Four entropy measures were tested: Approximate Entropy (ApEn), Sample Entropy (SampEn), Fuzzy Entropy (Fuzzy En) and Permutation Entropy (PE), each computed for ECG series of 1000, 500, 250 and 100 RR intervals. We found that with a reduction of the data set length...
-
Entropy Measures in the Assessment of Heart Rate Variability in Patients with Cardiodepressive Vasovagal Syncope
PublikacjaSample entropy (SampEn) was reported to be useful in the assessment of the complexity of heart rate dynamics. Permutation entropy (PermEn) is a new measure based on the concept of order and was previously shown to be accurate for short, non-stationary datasets. The aim of the present study is to assess if SampEn and PermEn obtained from baseline recordings might differentiate patients with various outcomes of the head-up tilt test...
-
Heart Rate Asymmetry, Its Compensation, and Heart Rate Variability in Healthy Adults during 48-h Holter ECG Recordings
Publikacja -
Yoga for Heart Rate Variability: A Systematic Review and Meta-analysis of Randomized Clinical Trials
Publikacja -
Classic electrocardiogram-based and mobile technology derived approaches to heart rate variability are not equivalent
Publikacja -
Measures of Heart Rate Variability in 24-h ECGs Depend on Age but Not Gender of Healthy Children
Publikacja -
Using Wearable Electronics to Estimate Usefulness of Heart Rate Variability for Bathing Person Identif Cation
PublikacjaIn this paper the possibility of person identification based on biosignal is investigated. The work focus on the analysis of the changes in intervals between successive R-waves of electrocardiogram (ECG) recorded by wearable electronics in form of a necklaces. The main idea behind this project is to find efficient tool which may prevent sudden consciousness loss episodes or even sudden death episodes related to rapid temperature...
-
Correlations between the Poincaré Plot and Conventional Heart Rate Variability Parameters Assessed during Paced Breathing
Publikacja -
Promising effects of xanthine oxidase inhibition by allopurinol on autonomic heart regulation estimated by heart rate variability (HRV) analysis in rats exposed to hypoxia and hyperoxia
Publikacja -
Relationship between heart rate variability, blood pressure and arterial wall properties during air and oxygen breathing in healthy subjects
PublikacjaPrevious studies reported that normobaric hyperoxia influences heart rate, arterial pressure, cardiac output and systemic vascular resistance, but the mechanisms underlying these changes are still not fully understood. Several factors are considered including degeneration of endothelium-derived nitric oxide by reactive oxygen species, the impact of oxygen-free radicals on tissues and alterations of autonomic nervous system function....
-
Independent Association Between Plasma Leptin Levels and Heart Rate in Heart Transplant Recipients
Publikacja -
Long-range dependencies in heart rate signals—revisited
Publikacja -
Heart rate asymmetry by Poincaré plots of RR intervals
Publikacja -
Analysis of correlation between heart rate and blood pressure
PublikacjaW artykule przedstawiono analizę korelacji pomiędzy częstością akcji serca (HR) i ciśnieniem krwi (BP). Wykorzystano rzeczywiste pomiary ciśnienia skurczowego i rozkurczowego krwi zmierzonego metodą inwazyjną w tętnicy promieniowej. Ze względu na możliwe zaszumienie sygnału przeanalizowano także dane po filtracji filttrem uśredniającycm oraz wykonano analizę trendów sygnałów. Wyniki analizy zarówno danych pomiarowych jak i filtrowanych...
-
Optical fiber head for monitoring of heart rate and blood oxygenation
Publikacja -
Chronographic Imprint of Age-Induced Alterations in Heart Rate Dynamical Organization
PublikacjaBeat-to-beat changes in the heart period are transformed into a network of increments between subsequent RR-intervals, which enables graphical descriptions of short-term heart period variability. Three types of such descriptions are considered: (1) network graphs arising from a set of vertices and directed edges, (2) contour plots of adjacency matrices A, representing the networks and transition matrices T, resulting from A, and (3)...
-
Generalised heart rate statistics reveal neurally mediated homeostasis transients
PublikacjaDistributions of accelerations and decelerations, obtained from increments of heart rate recorded during a head-up tilt table (HUTT) test provide short-term characterization of the complex cardiovascular response to a rapid controlled dysregulation of homeostasis. A generalised statistic is proposed for evaluating the neural reflexes responsible for restoring the homeostatic dynamics. An evaluation of the effects on heart rate...
-
Obstructive sleep apnea and heart rate asymmetry microstructure during sleep
Publikacja -
Visualization of short-term heart period variability with network tools as a method for quantifying autonomic drive
PublikacjaWe argue that network methods are successful in detecting nonlinear properties in the dynamics of autonomic nocturnal regulation in short-term variability. Two modes of visualization of networks constructed from RR-increments are proposed. The first is based on the handling of a state space. The state space of RR-increments can be modified by a bin size used to code a signal and by the role of a given vertex as the representation...
-
Renal denervation reduces office and ambulatory heart rate in patients with uncontrolled hypertension
Publikacja -
Baroreflex Control of Sympathetic Nerve Activity and Heart Rate in Obstructive Sleep Apnea
Publikacja -
Interactive Effect of Heart Rate and Muscle Sympathetic Nerve Activity on Blood Pressure
Publikacja -
Leptin interacts with heart rate but not sympathetic nerve traffic in healthy male subjects
Publikacja -
Wavelet Transform Analysis of Heart Rate to Assess Recovery Time for Long Distance Runners
PublikacjaThe diagnostics of the condition of athletes has become a field of special scientific interest and activity. The aim of this study was to verify the effect of a long (100 km) run on a group of runners, as well as to assess the recovery time that is required for them to return to the pre-run state. The heart rate (HR) data presented were collected the day before the extreme physical effort, on the same day as, but after, the physical...
-
Hyperventilation alters arterial baroreflex control of heart rate and muscle sympathetic nerve activity
Publikacja -
An independent relationship between plasma leptin and heart rate in untreated patients with essential hypertension
Publikacja -
Associations between heart rate asymmetry expression and asymmetric detrended fluctuation analysis results
Publikacja -
Frugal Heart Rate Correction Method for Scalable Health and Safety Monitoring in Construction Sites
Publikacja -
DETECTION OF BREATHING AND HEART RATE USING AN ECG SIGNAL MEASURED WHILE BATHING IN THE BATHTUB
PublikacjaNowadays a new area of interest is gaining importance - it is home biomedical examination. Intelligent home can be supported by set of devices for habitants observation. It can be particularly useful for elders or person with some health risks but living alone. One of critical locations within the house is bathroom. One of utilities in the bathroom is a bathtub which is sometimes preferred over shower. There are reports of problems...
-
Testing heart rate asymmetry in long, nonstationary 24 hour RR-interval time series
Publikacja -
Asymmetric Properties of the Heart Rate Microstructure in Healthy Adults during 48 h ECG Recordings
Publikacja -
The Impact of Intraspecies Variability on Growth Rate and Cellular Metabolic Activity of Bacteria Exposed to Rotating Magnetic Field
Publikacja -
Influence of the variability of the odour emission rate on its impact range: a case study of the selected industrial source
Publikacja -
Photoplethysmographic Time-Domain Heart Rate Measurement Algorithm for Resource-Constrained Wearable Devices and its Implementation
PublikacjaThis paper presents an algorithm for the measurement of the human heart rate, using photoplethysmography (PPG), i.e., the detection of the light at the skin surface. The signal from the PPG sensor is processed in time-domain; the peaks in the preprocessed and conditioned PPG waveform are detected by using a peak detection algorithm to find the heart rate in real time. Apart from the PPG sensor, the accelerometer is also used to...
-
Identification and management of the hypertensive patient with elevated heart rate: statement of a European Society of Hypertension Consensus Meeting
Publikacja -
Increased time varying heart rate and cardiovascular risk in hypertension – Benefit of selective I(f)channel inhibitor?
Publikacja -
Effect of Simultaneous Lower- and Upper-Body Ischemic Preconditioning on Lactate, Heart Rate, and Rowing Performance in Healthy Males and Females
Publikacja -
Comparison of Wavelet Transform Modulus Maxima and Multifractal Detrended Fluctuation Analysis of Heart Rate in Patients with Systolic Dysfunction of Left Ventricle
Publikacja -
Effect of beta-blocker therapy on heart rate response in patients with hypertension and newly diagnosed untreated obstructive sleep apnea syndrome
Publikacja -
Influence of duration of Type 1 (insulin-dependent) diabetes mellitus on 24-h ambulatory blood pressure and heart rate profile
Publikacja -
Differentiating patients with obstructive sleep apnea from healthy controls based on heart rate-blood pressure coupling quantified by entropy-based indices
PublikacjaWe introduce an entropy-based classification method for pairs of sequences (ECPS) for quantifying mutual dependencies in heart rate and beat-to-beat blood pressure recordings. The purpose of the method is to build a classifier for data in which each item consists of two intertwined data series taken for each subject. The method is based on ordinal patterns and uses entropy-like indices. Machine learning is used to select a subset...
-
Influence of Intensity RAMP Incremental Test on Peak Power, Post-Exercise Blood Lactate, and Heart Rate Recovery in Males: Cross-Over Study
Publikacja -
Heart rate PPG signals with acceleration captured at wrist during small and moderate body movements
Dane BadawczeHeart rate PPG signals with acceleration captured at wrist during small and moderate body movements
-
Cross-talk Between the Heart and Arteries in Older 65+ Adults
PublikacjaRegulatory synchronization between the heart and the arterial walls is essential for optimal blood delivery to tissues. We investigated functional coherence between heart rhythm and aortic wall compliance in 30 volunteers aged 65 – 74. ECG and carotid and iliac pulse-wave were recorded and digitized at 2 kHz. Carotid-femoral pulse-wave transit time (cfTT) which reflex aortic compliance was assessed using the intersecting tangent...