Heart rate and blood pressure variability in subjects with vasovagal syncope

Autonomic nervous system control in subjects with vasovagal syncope is controversial. In the present study, we used short-term spectral analysis to evaluate autonomic control in subjects with recurrent vasovagal syncope. We assessed the ability of spectral indices of HR (heart rate) variability to predict tilt-test responses. A series of 47 outpatients with recurrent vasovagal syncope and with positive responses to head-up tilt testing underwent a further study of RR variability during controlled breathing at rest and during tilt testing. During controlled breathing, RR interval variability of total power (TPRR; P<0.001), low-frequency power (LFRR; P<0.05), high-frequency power (HFRR; P<0.001) and HF expressed in normalized units (HFnuRR; P<0.001) were all higher, and LF expressed in normalized units (LFnuRR) and LF/HF ratio were lower in subjects with vasovagal syncope than in controls (P<0.001). To assess the ability of spectral components of RR variability to predict tilt-test responses, we prospectively studied 109 subjects with recurrent vasovagal syncope. The two normalized measures, HFnuRR and LFnuRR, determined during controlled breathing alone predicted a positive tilt-test response (sensitivity, 76%; specificity, 99%; positive predictive value, 96%; and negative predictive value, 90%). During tilting, subjects with vasovagal syncope had lower SBP (systolic blood pressure; P<0.05), LF component of peak SBP variability (LFSBP) and LFnuRR than controls, and higher TPRR, HFRR, HFnuRR and α HF (P<0.001). These spectral data indicate that vagal sinus modulation is increased at rest in subjects with vasovagal syncope. Spectral analysis of RR variability during controlled breathing, a procedure that predicts tilt-test responses, could be a useful guide in choosing the method of tilt testing.

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Abnormal passive head-up tilt test in subjects with symptoms of anxiety power spectral analysis study of heart rate and blood pressure

International Journal of Cardiology ◽

10.1016/s0167-5273(97)00088-0 ◽

1997 ◽

Vol 60 (2) ◽

pp. 121-131 ◽

Cited By ~ 51

Author(s):

Gianfranco Piccirillo ◽

Santagada Elvira ◽

Carmela Bucca ◽

Emanuela Viola ◽

Mauro Cacciafesta ◽

...

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Spectral Analysis ◽

Power Spectral Analysis ◽

Tilt Test ◽

Analysis Study ◽

Power Spectral ◽

Head Up Tilt ◽

Head Up Tilt Test

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Combined moderate and high intensity exercise with dietary restriction improves cardiac autonomic function associated with a reduction in central and systemic arterial stiffness in obese adults: a clinical trial

PeerJ ◽

10.7717/peerj.3900 ◽

2017 ◽

Vol 5 ◽

pp. e3900 ◽

Cited By ~ 4

Author(s):

Min Hu ◽

Shen Wang ◽

Dan Wang ◽

Qinhao Lai ◽

Xiaoying Chen ◽

...

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Arterial Stiffness ◽

Low Frequency ◽

Obese Adults ◽

Diet And Exercise ◽

Low Frequency Power ◽

Normalized Units ◽

Frequency Power ◽

Cardiac Autonomic Activity

Objective The present study aimed to assess the effects of exercise with dietary restriction on cardiac autonomic activity, arterial stiffness, and cardiovascular biomarkers in obese individuals. Methods Seventeen obese adults completed an 8-week exercise and dietary program. Anthropometry, body composition, and multiple biochemical markers were measured. We used carotid-femoral pulse wave velocity (cfPWV), brachial-ankle pulse wave velocity (baPWV), central blood pressure, and augmentation index (AIx) to assess arterial stiffness. To determine cardiac autonomic activity, heart rate variability (HRV) was analyzed by standard deviation of normal-to-normal intervals (SDNN), square root of the mean squared differences of successive normal-to-normal intervals (RMSSD), total power (TF), low-frequency power in normalized units (LFnu), high-frequency power in normalized units (HFnu), and low-frequency power/high-frequency power (LF/HF). Results Following the exercise and diet intervention, obese subjects had significant reductions in body weight, body mass index, body fat percentage, brachial systolic blood pressure, and resting heart rate, and they had shown improvements in blood chemistry markers such as lipid profiles, insulin, and high-sensitivity C-reactive protein. There was a significant reduction in both cfPWV and baPWV following the intervention when compared to baseline levels. Moreover, the AIx and aortic systolic blood pressure were significantly reduced after the intervention. The diet and exercise intervention significantly increased cardiac autonomic modulation (determined by improved SDNN, RMSSD, TP LF, HF, and LF/HF), which was partly due to changes in heart rate, insulin resistance, and the inflammatory pattern. Furthermore, we observed a correlation between enhanced cardiac autonomic modulation (LF/HF) and decreased arterial stiffness, as measured by central cfPWV and systemic baPWV. Discussion An 8-week combined intervention of diet and exercise is effective in improving cardiac autonomic function in obese adults, with an associated decrease in central and systemic arterial stiffness.

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Transfer Information Assessment in Diagnosis of Vasovagal Syncope Using Transfer Entropy

Entropy ◽

10.3390/e21040347 ◽

2019 ◽

Vol 21 (4) ◽

pp. 347

Author(s):

Katarzyna Buszko ◽

Agnieszka Piątkowska ◽

Edward Koźluk ◽

Tomasz Fabiszak ◽

Grzegorz Opolski

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Information Transfer ◽

Vasovagal Syncope ◽

Upright Position ◽

Transfer Entropy ◽

Tilt Test ◽

Study Group ◽

Head Up Tilt ◽

Passive Phase

The paper presents an application of Transfer Entropy (TE) to the analysis of information transfer between biosignals (heart rate expressed as R-R intervals (RRI), blood pressure (sBP, dBP) and stroke volume (SV)) measured during head up tilt testing (HUTT) in patients with suspected vasovagal syndrome. The study group comprised of 80 patients who were divided into two groups: the HUTT(+) group consisting of 57 patients who developed syncope during the passive phase of the test and HUTT(−) group consisting of 23 patients who had a negative result of the passive phase and experienced syncope after provocation with nitroglycerin. In both groups the information transfer depends on the phase of the tilt test. In supine position the highest transfer occurred between driver RRI and other components. In upright position it is the driver sBP that plays the crucial role. The pre-syncope phase features the highest information transfer from driver SV to blood pressure components. In each group the comparisons of TE between different phases of HUT test showed significant differences for RRI and SV as drivers.

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Predictive Value of Blood Pressure, Heart Rate, and Blood Pressure/Heart Rate Ratio in a Chinese Subpopulation with Vasovagal Syncope

Cardiovascular Innovations and Applications ◽

10.15212/cvia.2019.1266 ◽

2020 ◽

Author(s):

Dengfeng Geng

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Vasovagal Syncope ◽

Cost Effective ◽

Tilt Test ◽

Clinical Settings ◽

Mixed Response ◽

Head Up Tilt ◽

Head Up Tilt Test ◽

Mixed Pattern

Objective: The head-up tilt test (HUTT) is widely used but is time-consuming and not cost-effective to evaluate patients with vasovagal syncope (VVS). The present study aims to verify the hypothesis that ambulatory blood pressure (BP) monitoring (ABPM) and the simplistic tilt test may be potential alternatives to the HUTT.Methods: The study consecutively enrolled 360 patients who underwent the HUTT to evaluate VVS. BP), heart rate(HR), and BP/HR ratios derived from ABPM and the simplistic tilt test were evaluated to predict the presence, pattern, and stage of syncope during the HUTT.Results: Mixed response was the commonest pattern, and syncope occurred frequently with infusion of isoproterenol at a rate of 3 μg/min. During the simplistic tilt test, the cardioinhibitory group had higher tilted BP/HR ratios than the vasodepressor group, while the vasodepressor group had a faster tilted HR and a larger HR difference than the cardioinhibitory group. The higher the BP/HR ratio in the titled position, the higher the isoproterenol dosage needed to induce a positive response. During ABPM, BP/HR ratios were significantly higher in the cardioinhibitory group than in the vasodepressor group. The higher the ABPM-derived BP, the higher the dosage of isoproterenol needed to induce syncope. There were significant correlations in BP/HR ratios between ABPM and the supine position in the vasodepressor group, while significant correlation was found only for the diastolic BP/HR ratio between ABPM and the tilted position in the cardioinhibitory group. The mixed pattern shared correlative features of the other two patterns.Conclusion: ABPM and the simplistic tilt test might be used as promising alternatives to the HUTT in VVS evaluation in clinical settings.

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223 The bradycardia-hypotension reaction during head-up tilt test in patients with syncope: prevalence and value of blood pressure and heart rate behavior during the early stage of the test

EP Europace ◽

10.1016/s1099-5129(05)80134-5 ◽

2005 ◽

Vol 7 ◽

pp. 45-45

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Early Stage ◽

Tilt Test ◽

Head Up Tilt ◽

Rate Behavior ◽

Head Up Tilt Test

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P1514 Nitrate stimulate head up tilt testing potentiates the predictive value of the tilt test on the risk of recurrence in patients with vasovagal syncope

European Heart Journal ◽

10.1016/s0195-668x(03)94652-5 ◽

2003 ◽

Vol 24 (5) ◽

pp. 271

Author(s):

A AERTS

Keyword(s):

Predictive Value ◽

Vasovagal Syncope ◽

Tilt Test ◽

Risk Of Recurrence ◽

Tilt Testing ◽

Head Up Tilt

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Nitrate-stimulated tilt testing enhances the predictive value of the tilt test on the risk of recurrence in patients with suspected vasovagal syncope

Acta Cardiologica ◽

10.2143/ac.60.1.2005043 ◽

2005 ◽

Vol 60 (1) ◽

pp. 15-20 ◽

Cited By ~ 2

Author(s):

Arnaud J.J. AERTS ◽

Peter VANDERGOTEN ◽

Willem R.M. DASSEN ◽

Paul DENDALE

Keyword(s):

Predictive Value ◽

Vasovagal Syncope ◽

Tilt Test ◽

Risk Of Recurrence ◽

Tilt Testing

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Power spectral analysis of heart rate and blood pressure variability in anaesthetized dogs

Acta Physiologica Scandinavica ◽

10.1111/j.1748-1716.1992.tb09404.x ◽

1992 ◽

Vol 146 (2) ◽

pp. 155-164 ◽

Cited By ~ 37

Author(s):

A. E. HEDMAN ◽

J. E. K. HARTIKAINEN ◽

K. U. O. TAHVANAINEN ◽

M. O. K. HAKUMÄKI

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Spectral Analysis ◽

Blood Pressure Variability ◽

Power Spectral Analysis ◽

Power Spectral

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Effects of spinal cord transection on sympathetic discharge in decerebrate-unanesthetized cats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1989.257.6.r1506 ◽

1989 ◽

Vol 257 (6) ◽

pp. R1506-R1511 ◽

Cited By ~ 3

Author(s):

L. C. Weaver ◽

R. D. Stein

Keyword(s):

Blood Pressure ◽

Spinal Cord ◽

Heart Rate ◽

Spectral Analysis ◽

Spinal Cord Transection ◽

Renal Nerves ◽

Frequency Range ◽

Renal Nerve ◽

Sympathetic Discharge ◽

Nerve Discharge

Previous experiments in our laboratory have shown that discharge of splenic, mesenteric, and splanchnic nerves is well maintained after spinal cord transection in chloralose-anesthetized cats (8, 9, 11). The primary purpose of this investigation was to determine if maintained sympathetic discharge could be observed after spinal transection in the absence of chloralose anesthesia. In cats anesthetized with alphaxalone-alphadolone, changes in splanchnic discharge, blood pressure, and heart rate caused by decerebration and removal of the forebrain were observed. This procedure decreased blood pressure, increased heart rate, and had no immediate effect on sympathetic discharge or its rhythm (assessed by power density spectral analysis). One hour after decerebration and termination of anesthesia, splanchnic discharge had increased by approximately 36%. Next, effects of spinal cord transection on discharge of splanchnic, mesenteric, and renal nerves were observed in the decerebrate-unanesthetized cats. Splanchnic discharge decreased by 50%, mesenteric nerve discharge was unchanged, and renal nerve discharge decreased by 97%. Therefore, splanchnic nerve discharge was not as well maintained in decerebrate-unanesthetized cats as it had been in chloralose-anesthetized animals, and the remaining splanchnic discharge appeared to affect mesenteric nerves preferentially. Finally, spectral analysis of the splanchnic discharge demonstrated that before cord transection, most of the signal was in the 0- to 6-Hz frequency range, whereas after transection the proportion of signal in this frequency range was significantly reduced and the proportion in higher frequencies (7-25 Hz) was significantly increased. This loss of low-frequency rhythmicity is consistent with findings in our previous studies in chloralose-anesthetized cats.

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