Analysis of Respiratory Sinus Arrhythmia with Respect to Respiratory Phase

Abstract:We evaluated the respiratory modulation of heart rate, i.e., respiratory sinus arrhythmia (RSA), with respect to respiratory phase derived from an analytic signal from the lung volume curve, during spontaneous breathing and paced breathing with different patterns. The magnitudes and waveforms of RSA in the phase domain were similar regardless of breathing pattern, even including spontaneous breathing. An examination of the occurrence of heart beats with respect to the respiratory phase revealed that synchronized patterns recently reported in the literature (Nature 392: 239, 1998) were observed during paced breathing with breath holding periods whereby the respiratory phase advanced more slowly. It was concluded that the phase domain approach might be useful in extracting RSA during spontaneous breathing and for elucidating detailed mechanisms for RSA. However, the use of this technique for studies investigating cardio-respiratory coupling should be approached cautiously, as the results may be influenced by breathing patterns.

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Postural-induced phase shift of respiratory sinus arrhythmia and blood pressure variations: insight from respiratory-phase domain analysis

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00680.2007 ◽

2008 ◽

Vol 294 (3) ◽

pp. H1481-H1489 ◽

Cited By ~ 18

Author(s):

Kiyoshi Kotani ◽

Kiyoshi Takamasu ◽

Yasuhiko Jimbo ◽

Yoshiharu Yamamoto

Keyword(s):

Blood Pressure ◽

Phase Shift ◽

Respiratory Sinus Arrhythmia ◽

Domain Analysis ◽

Standing Position ◽

Sitting Position ◽

Sinus Arrhythmia ◽

Phase Domain ◽

Healthy Humans ◽

Respiratory Phase

The purpose of this study is to evaluate the multiple effects of respiration on cardiovascular variability in different postures, by analyzing respiratory sinus arrhythmia (RSA) and respiratory-related blood pressure (BP) variations for systolic BP (SBP), diastolic BP (DBP), and pulse pressure (PP) in the respiratory-phase domain. The measurements were conducted for 420 s on healthy humans in the sitting and standing positions, while the subjects were continuously monitored for heart rate and BP variability and instantaneous lung volume. The waveforms of RSA and respiratory-related BP variations were extracted as a function of the respiratory phase. In the standing position, the waveforms of the BP variations for SBP, DBP, and PP show their maxima at around the end of expiration (π rad) and the minima at around the end of inspiration (2 π rad), while the waveform of RSA is delayed by ∼0.35 π rad compared with the BP waveforms. On the other hand, in the sitting position, the phase of the DBP waveform (1.69 π rad) greatly and significantly ( P < 0.01) differs from that in the standing position (1.20 π rad). Also, the phase of PP is delayed and that of RSA is advanced in the sitting position ( P < 0.01). In particular, the phase shift of the DBP waveform is sufficiently large to alter whole hemodynamic fluctuations, affecting the amplitudes of SBP and PP variations. We conclude that the postural change associated with an altered autonomic balance affects not only the amplitude of RSA, but also the phases of RSA and BP variations in a complicated manner, and the respiratory-phase domain analysis used in this study is useful for elucidating the dynamic mechanisms of RSA.

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Human sinus arrhythmia: inconsistencies of a teleological hypothesis

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00716.2008 ◽

2009 ◽

Vol 296 (1) ◽

pp. H65-H70 ◽

Cited By ~ 28

Author(s):

Y. C. Tzeng ◽

P. Y. W. Sin ◽

D. C. Galletly

Keyword(s):

Gas Exchange ◽

Respiratory Sinus Arrhythmia ◽

Spline Interpolation ◽

Human Subjects ◽

Pulmonary Gas Exchange ◽

Respiratory Cycle ◽

Sinus Arrhythmia ◽

Paced Breathing ◽

Phase Domain ◽

Slow Breathing

Respiratory sinus arrhythmia (RSA) may serve an inherent function in optimizing pulmonary gas exchange efficiency via clustering and scattering of heart beats during the inspiratory and expiratory phases of the respiratory cycle. This study sought to determine whether physiological levels of RSA, enhanced by slow paced breathing, caused more heart beats to cluster in inspiration. In 12 human subjects, we analyzed the histogram distribution of heart beats throughout the respiratory cycle during paced breathing at 12, 9, and 6 breaths/min (br/min). The inspiratory period-to-respiratory period ratio was fixed at ∼0.5. RSA and its relationship with respiration was characterized in the phase domain by average cubic-spline interpolation of electrocardiographic R wave-to-R wave interval fluctuations throughout all respiratory cycles. Although 6 br/min breathing was associated with a significant increase in RSA amplitude ( P < 0.01), we observed no significant increase in the proportion of heart beats in inspiration ( P = 0.34). Contrary to assumptions in the literature, we observed no significant clustering of heart beats even with high levels of RSA enhanced by slow breathing. The results of this study do not support the hypothesis that RSA optimizes pulmonary gas exchange efficiency via clustering of heart beats in inspiration.

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Do Respiratory Sinus Arrhythmia and Respiratory Phase Durations Impact Heart Rate Variability Asymmetry in Healthy Subjects?

2020 11th Conference of the European Study Group on Cardiovascular Oscillations (ESGCO) ◽

10.1109/esgco49734.2020.9158025 ◽

2020 ◽

Author(s):

Beatrice De Maria ◽

Laura Adelaide Dalla Vecchia ◽

Monica Parati ◽

Francesca Perego ◽

Beatrice Cairo ◽

...

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Respiratory Sinus Arrhythmia ◽

Healthy Subjects ◽

Sinus Arrhythmia ◽

Respiratory Phase

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Influence of different breathing patterns on heart rate variability indices and reproducibility during experimental endotoxaemia in human subjects

Clinical Science ◽

10.1042/cs20110027 ◽

2011 ◽

Vol 121 (5) ◽

pp. 215-222 ◽

Cited By ~ 10

Author(s):

Matthijs Kox ◽

Jan C. Pompe ◽

Johannes G. van der Hoeven ◽

Cornelia W. Hoedemaekers ◽

Peter Pickkers

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Respiratory Rate ◽

Spontaneous Breathing ◽

Breathing Patterns ◽

Paced Breathing ◽

Cardiac Autonomic Nervous System ◽

Wide Range ◽

Static Conditions ◽

The Impact

HRV (heart rate variability) analysis is a widely employed method to assess cardiac autonomic nervous system activity. Accurate HRV measurement is critical to its value as a diagnostic and prognostic tool. Different breathing patterns may affect HRV, but results obtained under static conditions are conflicting. HRV indices decrease considerably during systemic inflammation evoked by experimental endotoxaemia, enabling the determination of the effects of different breathing patterns on HRV in a dynamic setting. We investigated the impact of different breathing patterns on short-term HRV measurements during experimental endotoxaemia. Furthermore, we assessed whether paced breathing improved HRV reproducibility. Twelve healthy male volunteers received an intravenous bolus (2 ng/kg of body weight) of endotoxin [LPS (lipopolysaccharide), derived from Escherichia coli O:113] on two occasions with an interval of 2 weeks. Five-minute HRV recordings were performed just prior to LPS administration and hourly thereafter until 8 h post-LPS. Three breathing protocols were employed every hour: (i) spontaneous breathing, (ii) metronome-guided breathing at the subject's normal respiratory rate (‘paced’) and (iii) metronome-guided breathing at 150% of the subject's normal respiratory rate (‘mild hyperventilation’). LPS administration resulted in a sharp decrease in all of the HRV indices measured, which was similar during both LPS administrations. Neither paced breathing nor mild hyperventilation influenced HRV indices compared with spontaneous breathing. Paced breathing did not improve reproducibility as it did not exert a significant effect on intra-subject coefficients of variation and intra-class correlation coefficients (calculated between both visits). In conclusion, over a wide range of HRV magnitudes during experimental endotoxaemia, neither paced breathing nor mild hyperventilation affected HRV indices. Moreover, paced breathing did not result in a significant improvement in reproducibility. Therefore employing a paced breathing protocol is not required to obtain valid HRV data during endotoxaemia.

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Estimation of cardiorespiratory transfer under spontaneous breathing conditions: a theoretical study

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1997.273.2.h1012 ◽

1997 ◽

Vol 273 (2) ◽

pp. H1012-H1023 ◽

Cited By ~ 4

Author(s):

T. S. Kim ◽

M. C. Khoo

Keyword(s):

Spontaneous Breathing ◽

Breathing Pattern ◽

Theoretical Study ◽

Simulated Data ◽

Periodic Breathing ◽

Breathing Patterns ◽

Tidal Breathing ◽

Sinus Arrhythmia ◽

Ventilatory Pattern ◽

Data Length

Using simulated noisy sequences of respiration and heart rate, we assessed the accuracy of the respiratory sinus arrhythmia transfer function (RSATF) estimation under three kinds of spontaneous breathing patterns: regular or tidal breathing, periodic breathing with apnea, and broadband breathing. Estimation employing the cross-power and autopower spectra of the simulated data produced RSATF estimates that were generally more variable than those computed with an autoregressive modeling approach. Variability and bias errors in the RSATF estimates became larger as respiratory bandwidth decreased when the breathing pattern changed from broadband to periodic to regular breathing. However, between frequencies of 0.1 and 0.3 Hz, these errors fell within 12% in all breathing patterns. Error in the RSATF estimates was only slightly increased, with reductions in data length to as low as 90 s. The results suggest the feasibility of obtaining accurate estimates of RSATF between 0.1 and 0.8 Hz from a wide variety of conditions, such as in different sleep-wake states where voluntary control of breathing is not possible and the ventilatory pattern may vary substantially.

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Does respiratory sinus arrhythmia occur in fishes?

Biology Letters ◽

10.1098/rsbl.2005.0365 ◽

2005 ◽

Vol 1 (4) ◽

pp. 484-487 ◽

Cited By ~ 15

Author(s):

Hamish A Campbell ◽

Edwin W Taylor ◽

Stuart Egginton

Keyword(s):

Heart Rate ◽

Respiratory Sinus Arrhythmia ◽

Selection Pressure ◽

Vagal Activity ◽

Sinus Arrhythmia ◽

Antarctic Species ◽

Power Spectral ◽

Spectral Statistics ◽

Respiratory Modulation ◽

Environmental Temperatures

The hypothesis that respiratory modulation of heart rate variability (HRV) or respiratory sinus arrhythmia (RSA) is restricted to mammals was tested on four Antarctic and four sub-Antarctic species of fish, that shared close genotypic or ecotypic similarities but, due to their different environmental temperatures, faced vastly different selection pressures related to oxygen supply. The intrinsic heart rate ( f H ) for all the fish species studied was ∼25% greater than respiration rate ( f V ), but vagal activity successively delayed heart beats, producing a resting f H that was synchronized with f V in a progressive manner. Power spectral statistics showed that these episodes of relative bradycardia occurred in a cyclical manner every 2–4 heart beats in temperate species but at >4 heart beats in Antarctic species, indicating a more relaxed selection pressure for cardio-respiratory coupling. This evidence that vagally mediated control of f H operates around the ventilatory cycle in fish demonstrates that influences similar to those controlling RSA in mammals operate in non-mammalian vertebrates.

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Respiratory sinus arrhythmia in humans: how breathing pattern modulates heart rate

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1981.241.4.h620 ◽

1981 ◽

Vol 241 (4) ◽

pp. H620-H629 ◽

Cited By ~ 206

Author(s):

J. A. Hirsch ◽

B. Bishop

Keyword(s):

Heart Rate ◽

Tidal Volume ◽

Respiratory Sinus Arrhythmia ◽

Spontaneous Breathing ◽

Low Frequency ◽

Corner Frequency ◽

Breath Hold ◽

Breathing Frequency ◽

Quiet Breathing ◽

Sinus Arrhythmia

The relationship of respiratory sinus arrhythmia amplitude (RSA) to tidal volume and breathing frequency was quantified during voluntarily controlled tidal volume and breathing frequency and spontaneous quiet breathing. Seventeen seated subjects breathed via mouthpiece and nose-clip, maintaining constant tidal volumes at each of several breathing frequencies. Inspiratory breath hold was zero frequency. Log RSA was plotted vs. log frequency for each tidal volume. The large stable RSA for frequencies less than 6 cycles/min was called low-frequency intercept (LFI, 20 +/- 5 beats/min). Low-frequency intercept was inversely proportional to a subject's age only to 35 yr. At higher breathing frequencies above a characteristic corner frequency (fC, 7.2 +/- 1.5 cycles/min) RSA decreased with constant slope (roll-off; 21 +/- 3.4 dB/decade). The RSA-volume relationship was linear permitting normalization of RSA-frequency curves for tidal volume to yield one curve. Spontaneous breathing data points fell on this curve. Voluntarily coupling of heart rate to breathing frequency in integer ratios reduced breath-by-breath variability of RSA without changing mean RSA. In conclusion, low-frequency intercept, corner frequency, and roll-off characterize an individual's RSA-frequency relationship during both voluntarily controlled and spontaneous breathing.

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The Interrelationship Between Pulmonary Mechanics and the Spontaneous Breathing Pattern in the Tokay Lizard, Gekko Gecko

Journal of Experimental Biology ◽

10.1242/jeb.113.1.203 ◽

1984 ◽

Vol 113 (1) ◽

pp. 203-214 ◽

Cited By ~ 3

Author(s):

WILLIAM K. MILSOM

Keyword(s):

Tidal Volume ◽

Spontaneous Breathing ◽

Breathing Pattern ◽

Pulmonary Ventilation ◽

Periodic Breathing ◽

Breath Holding ◽

Pulmonary Mechanics ◽

Respiratory Drive ◽

Breathing Patterns ◽

Gekko Gecko

The normal breathing pattern of the Tokay gecko (Gekko gecko) consists of single breaths or bursts of a few breaths separated by periods of breath holding. Increases in pulmonary ventilation that accompany rises in body temperature are caused by increases in respiratory frequency due to shortening of the periods of breath holding. Tidal volume and breath duration remain relatively constant. Measurements of the mechanical work associated with spontaneous breathing yielded values that were similar to those calculated for breaths of the same size and duration based on work curves generated during pump ventilation of anaesthetized animals. In this species, the pattern of periodic breathing and the ventilatory responses to changes in respiratory drive correspond with predictions of optimal breathing patterns based on calculations of the mechanical cost of ventilation. Bilateral vagotomy drastically alters the breathing pattern producing an elevation in tidal volume, a slowing of breathing frequency, and a prolongation of the breath duration. These alterations greatly increase the mechanical cost of ventilation. These data suggest that periodic breathing in this species may represent an adaptive strategy which is under vagal afferent control and which serves to minimize the cost of breathing.

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