Measuring physiological parameters of stress in horses during groundwork, for example when involved in equine-assisted interventions, is important to gain insight into the stress levels of the... Show moreMeasuring physiological parameters of stress in horses during groundwork, for example when involved in equine-assisted interventions, is important to gain insight into the stress levels of the horses. Heart rate and heart rate variability can be used as physiological indicators of stress in horses. Heart rate monitors could be easily incorporated into practice, as they are not expensive and easy to use. However, it is questionable whether heart rate monitors present accurate heart rate variability results in exercising horses, similar to electrocardiograms. The aim of this study was to determine the accuracy of heart rate monitors for the assessment of heart rate variability in horses during groundwork exercise. Simultaneous telemetric electrocardiograms (Televet) and heart rate monitor (Polar H10 transmitter and M430 receiver, Hylofit electrodes) recordings were performed on 28 horses (15 mares and 13 geldings). Results indicate that the heart rate monitor accurately determined heart rate and time-domain heart rate variability parameters when compared to electrocardiograms during both baseline and groundwork conditions. As expected, heart rate significantly increased and the heart rate variability significantly decreased during groundwork compared to baseline conditions. This indicates that the heart rate monitor can be used to accurately determine heart rate variability during groundwork. Show less
Wiersema, J.M.; Kamphuis, A.E.P.; Rohling, J.H.T.; Kervezee, L.; Akintola, A.A.; Jansen, S.W.; ... ; Spoel, E. van der 2022
Aging is associated with changes in heart rate (HR), heart rate variability (HRV), and 24-h rhythms in HR. Longevity has been linked to lower resting HR, while a higher resting HR and a decreased... Show moreAging is associated with changes in heart rate (HR), heart rate variability (HRV), and 24-h rhythms in HR. Longevity has been linked to lower resting HR, while a higher resting HR and a decreased HRV were linked to cardiovascular events and increased mortality risk. HR and HRV are often investigated during a short electrocardiogram (ECG) measurement at a hospital. In this study, we aim to investigate the relationship between HR parameters with familial longevity and chronological age derived from continuous ambulatory ECG measurements collected over a period of 24 to 90 hours. We included 73 middle-aged participants (mean (SD) age: 67.0 (6.16) years), comprising 37 offspring of long-lived families, 36 of their partners, and 35 young participants (22.8 (3.96) years). We found no association with familial longevity, but middle-aged participants had lower 24-h HR (average and maximum HR, not minimum HR), lower amplitudes, and earlier trough and peak times than young participants. Associations in HR with chronological age could be caused by the aging process or by differences in environmental factors. Interestingly, middle-aged participants had a less optimal HRV during long-term recordings in both the sleep and awake periods, which might indicate that their heart is less adaptable than that of young participants. This could be a first indication of deteriorated cardiovascular health in middle-aged individuals. Show less
Aim Heart rate (HR) is the most important parameter to evaluate newborns' clinical condition and to guide intervention during resuscitation at birth. The present study aims to compare the accuracy... Show moreAim Heart rate (HR) is the most important parameter to evaluate newborns' clinical condition and to guide intervention during resuscitation at birth. The present study aims to compare the accuracy of NeoBeat dry-electrode ECG for HR measurement with conventional ECG and pulse oximetry (PO). Methods Newborns with a gestational age >= 32 weeks and/or birth weight >= 1.5 kg were included when HR evaluation was needed. HR was simultaneously measured for 10 min with NeoBeat, PO and conventional ECG. Results A total of 18 infants were included (median (IQR) gestational age 39 (36-39) weeks and birth weight 3 150 (2 288-3 859) grams). Mean (SD) duration until NeoBeat obtained a reliable signal was 2.5 (9.0) s versus 58.5 (171.0) s for PO. Mean difference between NeoBeat and ECG was 1.74 bpm (LoA -4.987-8.459 and correlation coefficient 0.98). Paired HR measurements over 30-s intervals revealed no significant difference between NeoBeat and ECG. The positive predictive value of a detected HR <100 bpm by NeoBeat compared with ECG was 54.84%, negative predictive value 99.99%, sensitivity 94.44%, specificity 99.99% and accuracy 99.85%. Conclusions HR measurement with NeoBeat dry-electrode ECG at birth is reliable and accurate. Show less
Rationale: Assessing the relative contributions of cardioinhibition and vasodepression to the blood pressure (BP) decrease in tilt-induced vasovagal syncope requires methods that reflect BP... Show moreRationale: Assessing the relative contributions of cardioinhibition and vasodepression to the blood pressure (BP) decrease in tilt-induced vasovagal syncope requires methods that reflect BP physiology accurately. Objective: To assess the relative contributions of cardioinhibition and vasodepression to tilt-induced vasovagal syncope using novel methods. Methods and Results: We studied the parameters determining BP, that is, stroke volume (SV), heart rate (HR), and total peripheral resistance (TPR), in 163 patients with tilt-induced vasovagal syncope documented by continuous ECG and video EEG monitoring. We defined the beginning of cardioinhibition as the start of an HR decrease (HR) before syncope and used logarithms of SV, HR, and TPR ratios to quantify the multiplicative relation BP=SV center dot HR center dot TPR. We defined 3 stages before syncope and 2 after it based on direction changes of these parameters. The earliest BP decrease occurred 9 minutes before syncope. Cardioinhibition was observed in 91% of patients at a median time of 58 seconds before syncope. At that time, SV had a strong negative effect on BP, TPR a lesser negative effect, while HR had increased (allP<0.001). At the onset of cardioinhibition, the median HR was at 98 bpm higher than baseline. Cardioinhibition thus initially only represented a reduction of the corrective HR increase but was nonetheless accompanied by an immediate acceleration of the ongoing BP decrease. At syncope, SV and HR contributed similarly to the BP decrease (P<0.001), while TPR did not affect BP. Conclusions: The novel methods allowed the relative effects of SV, HR, and TPR on BP to be assessed separately, although all act together. The 2 major factors lowering BP in tilt-induced vasovagal syncope were reduced SV and cardioinhibition. We suggest that the term vasodepression in reflex syncope should not be limited to reduced arterial vasoconstriction, reflected in TPR, but should also encompass venous pooling, reflected in SV. Show less
Weijer, S. van de; Jong, R. de; Bijleveld, C.; Blokland, A.; Raine, A. 2017
Several prospective multigenerational studies have shown that crime runs in the family, while empirical research on the biological causes of crime has also established that low heart rate is... Show moreSeveral prospective multigenerational studies have shown that crime runs in the family, while empirical research on the biological causes of crime has also established that low heart rate is related to antisocial behavior. This study examines whether the intergenerational transmission of crime is moderated or mediated by a low heart rate of the son. Prospectively collected conviction data on 794 men from three consecutive generations of the Dutch Transfive dataset is used. Heart rates were measured around age 18, during the medical examination prior to the mandatory military service in the Dutch army. All analyses were conducted separately for violent and non-violent crime. Both paternal violence and low heart rate levels are associated with increased violent offending. Intergenerational transmission of violence was only found among families in which the son had a low heart rate, although the degree of transmission did not differ significantly from families in which the son had a high heart rate. No support was found for a mediating influence of low heart rates of criminals’ offspring on the intergenerational transmission of crime and violence. The results from this study underline the importance to focus on the interaction between biological risk factors and psychosocial risk factors for criminal behavior Show less
Nikolić, M.; Aktar, E.; Bögels, S.; Colonnesi, C.; De Vente, W. 2017
Background: Physiological hyperarousal in social situations is a characteristic of individuals with social anxiety disorder (SAD), but so far it has been rarely studied as a biological risk for SAD... Show moreBackground: Physiological hyperarousal in social situations is a characteristic of individuals with social anxiety disorder (SAD), but so far it has been rarely studied as a biological risk for SAD. Here, we investigate whether children at high risk for SAD (because of their parents' SAD) display physiological hyperarousal while interacting with a stranger. Also, we examine whether early physiological hyperarousal is related to later child social anxiety. Method: One hundred and seventeen children took part in the stranger-approach task when they were 2.5 and 4.5 years old. Heart rate (HR), heart rate variability (HRV), and electrodermal activity (EDA) were measured before, during, and after the conversation with a stranger. Both parents' lifetime SAD status and SAD severity were assessed before the birth of the child. Both parents and children reported on children's social anxiety symptoms when children were 7.5. Results: Children of parents with the lifetime SAD diagnosis did not differ in their physiological activity from children of parents without lifetime SAD. However, children of parents with more severe SAD displayed heightened EDA throughout the task procedure. Increased HR and reduced HRV during the stranger-approach and elevated EDA throughout the task phases were linked to later child social anxiety. Conclusions: Parents' severity of SAD is related to child physiological hyperarousal early in their childhood. In addition, physiological hyperarousal in early childhood predicts later child social anxiety. Together, these findings suggest that early physiological hyperarousal in social situations may pose a risk for later child social anxiety and that physiological hyperarousal, and EDA in particular, may be a biological mechanism in the intergenerational transmission of SAD. Show less
Akintola, A.A.; Pol, V. van de; Bimmel, D.; Maan, A.C.; Heemst, D. van 2016
