Utilizing heart rate variability: Midazolam prevents the sympathovagal imbalance caused by fentanyl/propofol induction

Background: The integrity of the autonomic nervous system (ANS) is essential for keeping physiological processes stable, even under stress. Since there is growing interest in heart rate variability (HRV) analysis for the noninvasive assessment of the ANS in sickle cell anemia (SCA) patients, we studied the behavior of the ANS in the presence of a stressor that simulates daily-life multitasking, the Glittre ADL test (GA-T). Objectives: To evaluate the involvement of the ANS using HRV in adults with SCA during the GA-T and to quantify the strength of the correlation of HRV with lung and muscle functions. Methods: In this cross-sectional study, 16 adults with SCA and 12 healthy controls without sickle cell disease underwent HRV assessment during the GA-T, pulmonary function tests (spirometry, diffusing capacity for carbon monoxide (DLCO), and respiratory muscle testing). Peripheral muscle function [handgrip strength (HGS) and quadriceps strength (QS)] were also measured. Results: Compared to the healthy controls, adults with SCA showed lower HRV, with worse parasympathetic modulation due to reductions in the following indices: the root-mean-square difference of successive normal iRRs (iRR) (RMSSD); the percentage of pairs of consecutive iRRs whose difference is > 50 m (pNN50); the high-frequency component of heart rate variability (HF); and the standard deviation of instantaneous beat-to-beat variability (SD1) (P < 0.001 for all). Compared to healthy controls, individuals with SCA showed greater sympathovagal imbalance (higher ratio between low-frequency and HF components) and lower complexity of the ANS (lower approximate entropy). The GA-T time was correlated with parasympathetic activity indices: RMSSD (rs = -0.650, P < 0.01); pNN50 (rs = -0.932, P < 0.0001), HF (rs = -0.579, P < 0.01), and SD1 (rs = -0.814, P < 0.0001). Correlations between parasympathetic activity indices and DLCO, HGS, and QS measures were also significant. Conclusions: Adults with SCA have low HRV, with low parasympathetic activity, sympathovagal imbalance, and abnormal ANS complexity. In addition, lower HRV is associated with longer GA-T time, greater impairment of pulmonary diffusion, and greater muscle strength dysfunction.

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Comparative study of heart rate variability in normotensive young adults with family history of hypertension

International Journal of Research in Medical Sciences ◽

10.18203/2320-6012.ijrms20210051 ◽

2021 ◽

Vol 9 (2) ◽

pp. 371

Author(s):

Ovais K. Wadoo ◽

Sheikh I. Sayeed ◽

Mariya R. Tramboo

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

High Frequency ◽

Low Frequency ◽

Vascular Diseases ◽

Test Group ◽

Time Domain Analysis ◽

Domain Analysis ◽

Control Group ◽

Sympathovagal Imbalance

Background: Hypertension is a risk factor for the development of cardiovascular and cerebro-vascular diseases. Autonomic nervous system plays a crucial role in the development of hypertension. The integrity of autonomic modulation of heart rate is evaluated by analysing heart rate variability (HRV), which refers to oscillations in the intervals between consecutive heartbeats or R-R intervals. The present study was designed to analyse the indices of heart rate variability in the offsprings of hypertensive parents and off springs of normotensive parents to understand if there is any autonomic imbalance between the two groups. Methods: The study was conducted in the Department of Physiology, Government Medical College, Srinagar. The test group consisted of 30 healthy normotensive subjects studying in 1st year of MBBS with hypertensive parents and the control group consisted of healthy normotensive of 1st year of MBBS with both parents normotensive. In time domain analysis the standard deviation of all normal-to-normal intervals {SDNN(ms)} was taken as index of overall HRV. Frequency domain analysis was done with respect to low frequency (LF) analysis and high frequency (HF) analysis. Low and high frequency power were expressed in normalized units.Results: The SDNN was reduced in cases but was not statistically significant. RMSSD was also reduced in cases though not statistically significant. LFnu was found to be significantly higher in cases. The HFnu was significantly reduced in cases. LF/HF ratio was found to be higher in cases and the difference was statistically significant. Conclusions: Our study reveals that incidence of prehypertension and the risk of cardiovascular dysfunction in relation to sympathovagal imbalance is more in the off springs of hypertensive parents than in the off springs of normotensive parents. Sympathovagal imbalance in the form of increased sympathetic drive and decreased parasympathetic drive can lead to prehypertension in these genetically predisposed individuals.

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Sympathovagal imbalance in hyperthyroidism

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.2001.281.1.e190 ◽

2001 ◽

Vol 281 (1) ◽

pp. E190-E195 ◽

Cited By ~ 36

Author(s):

J. Burggraaf ◽

J. H. M. Tulen ◽

S. Lalezari ◽

R. C. Schoemaker ◽

P. H. E. M. De Meyer ◽

...

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

High Frequency ◽

Spectral Power ◽

Systemic Exposure ◽

Urinary Catecholamine ◽

Catecholamine Excretion ◽

Euthyroid State ◽

Sympathovagal Imbalance ◽

Hyperthyroid Patients

We assessed sympathovagal balance in thyrotoxicosis. Fourteen patients with Graves' hyperthyroidism were studied before and after 7 days of treatment with propranolol (40 mg 3 times a day) and in the euthyroid state. Data were compared with those obtained in a group of age-, sex-, and weight-matched controls. Autonomic inputs to the heart were assessed by power spectral analysis of heart rate variability. Systemic exposure to sympathetic neurohormones was estimated on the basis of 24-h urinary catecholamine excretion. The spectral power in the high-frequency domain was considerably reduced in hyperthyroid patients, indicating diminished vagal inputs to the heart. Increased heart rate and mid-frequency/high-frequency power ratio in the presence of reduced total spectral power and increased urinary catecholamine excretion strongly suggest enhanced sympathetic inputs in thyrotoxicosis. All abnormal features of autonomic balance were completely restored to normal in the euthyroid state. β-Adrenoceptor antagonism reduced heart rate in hyperthyroid patients but did not significantly affect heart rate variability or catecholamine excretion. This is in keeping with the concept of a joint disruption of sympathetic and vagal inputs to the heart underlying changes in heart rate variability. Thus thyrotoxicosis is characterized by profound sympathovagal imbalance, brought about by increased sympathetic activity in the presence of diminished vagal tone.

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Relation of Body mass index to Heart rate variability in female medical students

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v11i3.2761 ◽

2020 ◽

Vol 11 (3) ◽

pp. 4722-4725

Author(s):

Adlin. K. Kazia ◽

Sangeetha A ◽

Mahammad Rafi V ◽

Prem Kumar S ◽

Vishnuprasaath S ◽

...

Keyword(s):

Body Mass Index ◽

Heart Rate ◽

Heart Rate Variability ◽

Body Mass ◽

Low Frequency ◽

Normal Weight ◽

Obesity Prevalence ◽

Young Females ◽

Cardiac Autonomic Dysfunction ◽

Sympathovagal Imbalance

Heart rate variability (HRV) is a simple non-invasive, sensitive measure to evaluate autonomic system activity. Sympathovagal imbalance can explain increased incidence of sudden cardiac deaths associated with increased Body Mass Index (BMI). Understanding the mechanism that connects obesity and autonomic nervous system (ANS) functions is important because increasing obesity prevalence documented among men and women of all ages. The aim of the study is to assess the relationship of body mass index to heart rate variability in young females. In this study, 90 healthy female students, aged between 17-22 years were included. After calculating the BMI, subjects were divided into three groups. HRV was recorded for 5 min using INCO-NIVIQURE DIGITAL ACQUISITION SYSTEM VER.52.0. Low frequency (LF) component, high frequency (HF) component and LF:HF ratio were recorded and the relation between BMI, HF, LF and LF:HF ratio were analysed using ANOVA test. In this study, LF:HF ratio in overweight females was found to be high and parasympathetic was decrease when compared to normal weight and underweight females. Raised BMI is associated with reduced HRV, which correlates with decreased parasympathetic activity and sympathovagal imbalance, thus increases the chances of cardiac autonomic dysfunction and eventually leading to cardiovascular disease in overweight female.

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Sleep-related sympathovagal imbalance in SHR

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00418.2003 ◽

2004 ◽

Vol 286 (3) ◽

pp. H1170-H1176 ◽

Cited By ~ 38

Author(s):

Terry B. J. Kuo ◽

Ching J. Lai ◽

Fu-Zen Shaw ◽

Chi-Wan Lai ◽

Cheryl C. H. Yang

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Paradoxical Sleep ◽

Power Spectral Analysis ◽

Sprague Dawley ◽

Quiet Sleep ◽

Sympathovagal Imbalance ◽

Wistar Kyoto ◽

Continuous Power ◽

Frequency Power

The role of the autonomic nervous system in spontaneous hypertension during each stage of the sleep-wake cycle remains unclear. The present study attempted to evaluate the differences in cardiac autonomic modulations among spontaneously hypertensive rats (SHR), normotensive Wistar-Kyoto rats (WKY), and Sprague-Dawley rats (SD) across sleep-wake cycles. Continuous power spectral analysis of electroencephalogram, electromyogram, and heart rate variability was performed in unanesthetized free moving rats during daytime sleep. Frequency-domain analysis of the stationary R-R intervals (RR) was performed to quantify the high-frequency power (HF), low-frequency power (LF)-to-HF ratio (LF/HF), and normalized LF (LF%) of heart rate variability. WKY and SD had similar mean arterial pressure, which is significantly lower than that of SHR during active waking, quiet sleep, and paradoxical sleep. Compared with WKY and SD, SHR had lower HF but similar RR, LF/HF, and LF% during active waking. During quiet sleep, SHR developed higher LF/HF and LF% in addition to lower HF. SHR ultimately exhibited significantly lower RR accompanied with higher LF/HF and LF% and lower HF during paradoxical sleep compared with WKY. We concluded that significant cardiac sympathovagal imbalance with an increased sympathetic modulation occurred in SHR during sleep, although it was less evident during waking.

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