Background Many cardiocirculatory mechanisms are involved in the adaptation to orthostatic stress. While these mechanisms may be impaired in Fontan patients. However, it is yet unclear how Fontan patients, who exhibit a critical fluid balance, respond to orthostatic stress. Angiotensin converting enzyme inhibitors are often prescribed to Fontan patients, but they may negatively influence orthostatic tolerance. Therefore, we evaluated the response to orthostatic stress in pediatric Fontan patients before and after treatment with enalapril. Methods Thirty-five Fontan patients (aged 14 years) with moderate-good systolic ventricular function without pre-existent enalapril treatment were included. Before and after a three-month enalapril treatment period, the hemodynamic response to head-up tilt test was evaluated by various parameters including cardiac index, blood pressure, cerebral blood flow, aortic stiffness and cardiac autonomous nervous activity. Thirty-four healthy subjects (aged 13 years) served as controls. Results Fontan patients had a decreased cerebral blood flow and increased aortic stiffness in the supine position compared to controls, while all other factors did not differ. Patients and controls showed a comparable response to head-up tilt test for most parameters. Twenty-seven patients completed the enalapril study with a mean dosage of 0.3±0.1mg/kg/day. Most parameters were unaffected by enalapril, only the percent decrease in cardiac index to tilt was higher after treatment, but the cardiac index during tilt was not lower (3.0L/min/m2 pre-enalapril versus 2.8L/min/m2 after treatment; P = 0.15). Conclusion Pediatric Fontan patients adequately respond to orthostasis with maintenance of blood pressure and cerebral blood flow and sufficient autonomic response. Enalapril treatment did not alter the response. Clinical trial information Scientific title: ACE inhibition in Fontan patients: its effect on body fluid regulation (sAFE-study). The Netherlands National Trial Register: Trail NL6415. Registered 2017-07-20. Trial information: https://www.trialregister.nl/trial/6415

Objective
Dysregulated children experience significant impairment in regulating their affect, behavior, and cognitions and are at risk for numerous adverse sequelae. The unclear phenomenology of their symptoms presents a barrier to evidence-based diagnosis and treatment.
Method
The cognitive, behavioral, and psychophysiological mechanisms of dysregulation were examined in a mixed clinical and community sample of 294 children ages 7-17 using the Research Domain Criteria constructs of cognitive control and frustrative nonreward.
Results
Results showed that caregivers of dysregulated children viewed them as having many more problems with everyday executive function than children with moderate or low levels of psychiatric symptoms; however, during standardized assessments of more complex cognitive control tasks, performance of dysregulated children differed only from children with low symptoms on tests of cognitive flexibility. In addition, when frustrated, dysregulated children performed more poorly on the Go/No-Go Task and demonstrated less autonomic flexibility as indexed by low respiratory sinus arrhythmia and pre-ejection period scores.
Conclusion
The findings of this study suggest that autonomic inflexibility and impaired cognitive function in the context of frustration may be mechanisms underlying childhood dysregulation.

This study examined the acute immunological effects of two laboratory stressors, expected to evoke distinct patterns of cardiac autonomic activity; namely an “active coping” time-paced memory test, and a “passive coping” stressful video showing surgical operations. We measured salivary S-IgA, IgA-subclasses (IgA1, IgA2), and secretory component (SC). SC is responsible for the transport of S-IgA across the epithelium, and thus a rate-determining step in S-IgA secretion. Thirty-two male undergraduates were subjected to both stressors and a control video (a didactic television program). The memory test induced a typical “fight-flight” response, characterized by increases in heart rate and blood pressure in association with a decrease in cardiac preejection period (PEP) and vagal tone. The surgical video produced a “conservation-withdrawal”-like response, characterized by an enhanced vagal tone, a decrease in heart rate, and a moderate sympathetic coactivation (as indicated by a shortened PEP and an increased systolic pressure). The memory test induced an increase in the concentration and, to a lesser extent, in the output of S-IgA, IgA], and SC. The output of IgA2 was not significantly affected. For the surgical video, a different pattern emerged: During stressor exposure S-IgA remained unaffected, against the background of a small increase in SC output. However, 10 min after the surgical video S-IgA levels had decreased. This decrease in S-IgA was paralleled by a decrease in IgA1, but not IgA2. We conclude that acute stress can have both enhancing and suppressive effects on secretory immunity, the IgA1 subclass in particular. The mechanisms that underlie these divergent responses may include stressor-specific patterns of autonomic activation.

Objective 
To test the validity of ambulatory heart rate (HR) assessment with a cuff ambulatory blood pressure (ABP) monitor.
Design 
Cross-instrument comparison of HR measured intermittently by a cuff ABP monitor (SpaceLabs, Redmond, Washington, USA), with HR derived from continuous electrocardiogram (ECG) recordings (1) in a controlled laboratory experiment and (2) during long-term recording in a true naturalistic setting.
Participants 
Six normotensive subjects participated in the laboratory study. A total of 109 male white-collar workers underwent ambulatory monitoring, of which 30 were mildly hypertensive.
Methods 
Four different laboratory conditions (postures: lying, sitting, standing, walking), repeated twice, were used to assess the short-term effects of cuff inflation on the HR. To test the actual ambulatory validity, participants simultaneously wore a continuous HR recorder and the ABP monitor from early morning to late evening on 2 workdays and one non-workday. Diary and vertical accelerometery information was used to obtain periods of fixed posture and (physical) activity across which HR from both devices was compared.
Results. 
Laboratory results showed that the ABP device reliably detected HR during blood pressure measurement, but that this HR was systematically lower than the HR directly before and after the blood pressure measurement. The ambulatory study confirmed this systematic underestimation of the ongoing HR, but additionally showed that its amount increased when subjects went from sitting to standing to light physical activity (2.9; 4.3 and 9.1 bpm (beats/min), respectively). In spite of this activity-dependent underestimation of HR, the correlation of continuous ECG and intermittent ABP-derived HR was high (median r = 0.81). Also, underestimation was not different for normotensives and mild hypertensives.
Conclusions 
A direct effect of cuff inflation leads to the underestimation of ongoing HR during cuff-based ABP measurement. Additional underestimation of HR occurs during periods with physical activity, probably due to behavioural freezing during blood pressure measurements. HR underestimation was not affected by hypertensive state. When its limitations are taken into account, ABP-derived ambulatory HR can be considered a reliable and valid measure.

STUDY OBJECTIVES: Recent work indicates that cardiac sympathetic activity is not influenced by the circadian system and instead decreases after sleep onset. However, little is known about the pattern of change in cardiac sympathetic activity during NREM/REM sleep cycles and whether this is associated with alterations in slow-wave activity (SWA). To address these questions, we examined SWA, cardiac sympathetic activity, heart rate and rectal and foot temperatures during the first three NREM/REM sleep cycles and during transitions between NREM and REM sleep.
DESIGN: Subjects were required to maintain a constant sleep-wake cycle for at least a week and have at least one adaptation night, before their night of recording.
SETTING: Individual temperature controlled bedrooms.
PARTICIPANTS: 10 young healthy males and females.
INTERVENTIONS: NA.
MEASUREMENTS AND RESULTS: All variables showed the greatest change in the first NREM cycle. Specifically, SWA, sympathetic activity, heart rate and foot temperature increased while rectal temperature decreased. After the initial increase, cardiac sympathetic activity decreased across the sleep phase, in association with a decrease in heart rate. Cardiac sympathetic activity did not significantly alter across NREM-REM cycles.
CONCLUSIONS: The results suggest that increases in heart rate and cardiac sympathetic activity early in the sleep period are, in part, a compensatory reaction to the concomitant thermoregulatory changes observed. These results also indicate that the effect of time asleep on cardiac sympathetic activity may be greater than the influence of sleep cycles. These results are discussed with reference to the recuperative value of naps.

The effects of variables derived from a work stress theory (the effort–reward imbalance theory) on the power in the high frequency (HF_HRV) band of heart rate (0.14–0.40 Hz) throughout a work day, were determined using multilevel analysis. Explanatory variables were analysed at two levels: at the lowest level (within-day level), the effects of positive mood, negative mood, demand, satisfaction, demand-satisfaction ratio, and time of day were assessed. At the highest level (the subject level), the effects of sleep quality, effort, reward, effort–reward imbalance, need for control, type of work (profession), negative affectivity, gender and smoking on HF_HRV were assessed. Need for control has a negative effect on HF_HRV after controlling for time of day effects, i.e. subjects with a high need for control have a lower vagal control of the heart. In the long run, these subjects may be considered to be at increased health risk, because they have less of the health protective effects of vagal tone. The interaction between effort–reward imbalance and time of day has a positive effect on HF_HRV, i.e. the cardiac vagal control of subjects with a high effort–reward imbalance increases as the day progresses. It is discussed that this probably reflects reduced effort allocation, ensuing from disengagement from the work demands.

In a longitudinal study of Dutch adolescent and young adult twins, their parents and their siblings, questionnaire data were collected on depression, anxiety and correlated personality traits, such as neuroticism. Data were collected by mailed surveys in 1991, 1993, 1995 and 1997. A total of 13,717 individuals from 3344 families were included in the study. To localise quantitative trait loci (QTLs) involved in anxiety and depression, the survey data were used to select the most informative families for a genome-wide search. For each individual a genetic factor score was computed, based on a genetic multivariate analysis of anxiety, depression, neuroticism and somatic anxiety. A family was selected if at least two siblings (or DZ twins) had extreme factor scores. Both discordant (high-low) and concordant (high-high and low-low) pairs were included in the selected sample. Once an extreme sibling pair was selected, all family members (parents and additional siblings of the selected pair) who had at least once returned a questionnaire booklet were asked to provide a DNA sample. In total, 2724 individuals from 563 families (1007 parents and 1717 offspring) were approached and 1975 individuals from 479 families (643 patients and 1332 offspring) complied by returning a buccal swab for DNA isolation. All offspring from selected families were asked to participate in a psychiatric interview and in a 24-hour ambulatory assessment of cardiovascular parameters and cortisol. The interview consisted of the WHO-Composite International Diagnostic Interview and was administered to 1253 offspring. In this paper we describe the genetic-epidemiological analyses of the survey data on anxiety, somatic anxiety, neuroticism and depression. We detail how these data were used to select families for the QTL study and discuss strategies that may help elucidate the molecular pathways leading from genes to anxious depression.

The role of the autonomic nervous system in secretory
immunoglobulin A (sIgA) responses to laboratory challenge
was explored in a study in which sIgA and cardiovascular
activity were recorded at rest and during mental arithmetic
and paced breathing. These tasks were selected to preferentially
engage the sympathetic and parasympathetic nervous systems,
respectively. Mental arithmetic elicited a mixed pattern
of increased alpha- and beta-adrenergic activity and a
reduction in parasympathetic activity; diastolic blood
pressure, total peripheral resistance, and systolic blood
pressure increased, preejection period shortened, and heart
rate variability decreased. In contrast, paced breathing
primarily elicited an increase in parasympathetic activity;
heart rate variability increased. Mental arithmetic also
provoked an increase in sIgA concentration but no change
in saliva volume, whereas paced breathing affected neither
sIgA concentration nor saliva volume. These data suggest
that sIgA responses to laboratory challenges are mediated
by sympathetic rather than parasympathetic processes.

reviews our current experience with a recently developed device (VU-AMD [ambulatory monitoring device]) for the ambulatory measurement of the electrocardiogram (EKG) and changes in thoracic impedance (ICG) / with this device simultaneous assessment can be made of HR [heart rate], HR variability (HRV), the pre-ejection period (PEP), left ventricular ejection time (LVET), respiration rate (RR) and respiratory sinus arrhythmia (RSA) / PEP and RSA are currently our best noninvasive tools to assess sympathetic and parasympathetic influences on the heart reliability of the VU-AMD was tested in cross-instrument comparison against the “golden standard” of our laboratory devices / to determine feasibility [and validity] of field measurements, a set of 40 Ss has been measured on a 24-hr basis / as a final step we explored the possibilities of this new technique for research into behaviorally induced cardiovascular pathology / in 2 studies, 24-hr profiles of PEP and RSA were obtained with the VU-AMD in S groups with different risk profiles for cardiovascular disease [presence vs absence of insulin resistance syndrome and exercisers vs non-exercisers] (PsycInfo Database Record (c) 2020 APA, all rights reserved)