Results 191 to 200 of about 892,215 (229)

Respiratory Sinus Arrhythmia and Chaos

2008 2nd International Conference on Bioinformatics and Biomedical Engineering, 2008
To investigate the chaotic characteristic of respiratory sinus arrhythmia and nonlinearity in heart rate variability (HRV), two kinds of voluntary breathing, namely, paced breathing and breath-holding, were compared with spontaneous breathing. High frequency component (HF) and its band width of HRV were changed according to respiratory patterns ...
J.-T. Sun, Y. Fang, Cheng Li, Guo-Qiang Wu, Chi-Sang Poon   +4 more
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Modulation of Respiratory Sinus Arrhythmia by Breathing Pattern

Clinical Science, 1996
Respiratory sinus arrhythmia (RSA) of healthy humans is dependent on multiple factors like heart rate itself, blood pressure, stroke volume and sympatho-vagal tone. Respiration is a dominant factor causing an extended variability of heart rate, and is frequently used for testing the status of autonomic nervous system [I].
C, Haggenmiller, J H, Baumert, M, Adt, A W, Frey   +3 more
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Determinants of respiratory sinus arrhythmia in the vagotomized rabbit

American Journal of Physiology-Heart and Circulatory Physiology, 1995
After cardiac denervation, a small-amplitude respiratory sinus arrhythmia (RSA) has been described in animals and humans. Its mechanical and chemical determinants were investigated in 19 urethan-anesthetized, vagotomized, and mechanically ventilated rabbits. We measured the influence on RSA of arterial blood gases, beta-adrenergic blockade, and phasic
PERLINI, STEFANO, Soldá PL, Piepoli M, Sala Gallini G, Calciati A, Finardi G, BERNARDI, LUCIANO   +6 more
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Aging as a Modulator of Respiratory Sinus Arrhythmia

Journal of Gerontology, 1993
Aging is associated with an accentuated shift toward sympathetic outflow. Evidence suggests that sympathetic and vagal-cardiac activity change reciprocally. If this hypothesis is correct, then aging would result in an attenuation of vagal-cardiac activity.
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Respiratory sinus arrhythmia in the denervated human heart

Journal of Applied Physiology, 1989
We performed this study to test whether the denervated human heart has the ability to manifest respiratory sinus arrhythmia (RSA). With the use of a highly sensitive spectral analysis technique (cross correlation) to define beat-to-beat coupling between respiratory frequency and heart rate period (R-R) and hence RSA, we compared the effects of ...
BERNARDI, LUCIANO, KELLER F., SANDERS M., REDDY P.S., GRIFFITH B., MENO F., PINSKY M.R.   +6 more
openaire   +2 more sources

Nonlinear Interpretation of Respiratory Sinus Arrhythmia in Anesthesia

Methods of Information in Medicine, 1994
Abstract:A non-parametric method is presented for modelling nonlinear dynamic mechanisms of respiratory sinus arrhythmia (RSA) in anesthesia caused by positive pressure ventilation. RR interval sequences are shown with Tsay’s linearity test to contain both short-term and long-term nonlinear components, which cannot completely be modelled with optimal ...
P, Loula, T, Lipping, V, Jäntti, A, Yli-Hankala   +3 more
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Respiratory sinus arrhythmia and cognitive functioning in children

Developmental Psychobiology, 2008
AbstractWe examined associations between children's cognitive performance and both basal respiratory sinus arrhythmia (RSA) and RSA regulation to a reaction time task. Cognitive performance was examined in the lab via standardized tests of cognitive functioning (Woodcock–Johnson III) and a reaction time task.
Lori, Staton, Mona, El-Sheikh, Joseph A, Buckhalt   +2 more
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Respiratory Sinus Arrhythmia and Cardiovascular Responses to Stress

Psychophysiology, 1992
ABSTRACTThe parasympathetic nervous system provides mechanisms that could attenuate sympathetically mediated heart rate stress responses and might have even more general antagonistic actions on stress reactivity. Individuals characterized by higher levels of parasympathetic tone might, through such mechanisms, be less reactive when stimuli elicit ...
J D, Lane, R A, Adcock, R E, Burnett
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The Respiratory Sinus Arrhythmia: A Measure of Cardiac Age

Science, 1984
A method developed for quantifying respiratory sinus arrhythmia (RSA) during voluntary cardiorespiratory synchronization relies on computer-assisted rhythmometric cosinor analysis of instantaneous heart rate data. The RSA was present in all subjects tested, even those at advanced ages. The amplitude of the RSA falls approximately 10 percent per decade.
W J, Hrushesky, D, Fader, O, Schmitt, V, Gilbertsen   +3 more
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Acute effects of bisoprolol on respiratory sinus arrhythmia

Fundamental & Clinical Pharmacology, 1998
Summary— Respiratory sinus arrhythmia (RSA) is often quantified by computing the spectra of heart period (HP) or of its reciprocal heart rate (HR) at the respiratory frequency. This study was undertaken to describe the effect of an acute beta‐blockade achieved with bisoprolol on RSA, obtained during a calibrated breathing (breathing frequency 0.25 Hz ...
M, Wargon, D, Laude, A, Girard, J L, Elghozi   +3 more
openaire   +2 more sources