Comprehensive linear and nonlinear heart rate variability normative data in children.

BACKGROUND: The autonomic nervous system (ANS) is critical in regulating involuntary bodily functions, including heart rate. Heart rate variability (HRV) reflects the complex interplay between the ANS and humoral factors, making it a valuable noninvasive tool for assessing autonomic function. While HRV has been extensively studied in adults, normative data for HRV in children, primarily based on long-term rhythm recordings, are limited. OBJECTIVE: This study aimed to establish comprehensive normative data for HRV in children. METHODS: In this retrospective study, we examined 24-h Holter monitors of children aged 1 day to 18 years, divided into six age groups, at Nemours Children's Health in Orlando, Florida, spanning the years 2013-2023. HRV analysis encompassed time-domain, frequency-domain, and nonlinear indices. RESULTS: Holter data for a total of 247 patients in six age groups were included. An age-related uptrend was observed in all time- and frequency-domain variables except the normalized unit of low-frequency power. Entropy analysis revealed contradictory results among different entropy techniques. Sample and approximate entropy analyses were consistent and showed less complexity and more predictability of HRV with decreasing heart rate, while Shannon entropy analysis showed the opposite. Fractal detrended fluctuation analysis exhibited significant decreases across the age groups, suggestive of diminishing self-similarity of HRV patterns. CONCLUSION: Control of heart rate and HRV is a highly complex process and requires further study for a better understanding. It seems that no single parameter can fully elucidate the entire process. A combination of time-domain, frequency-domain, and nonlinear indices may be necessary to explain HRV behavior in the growing body.

The Prevalence of Anxiety and Depression in Children With Postural Orthostatic Tachycardia Syndrome (POTS): A Retrospective Study.

INTRODUCTION: Postural orthostatic tachycardia syndrome (POTS) is a chronic form of orthostatic intolerance characterized by various symptoms such as dizziness, lightheadedness, and increased heart rate. Conflicting reports exist regarding the prevalence of anxiety and depression in adults with POTS, while data on pediatric POTS remains scarce. METHOD: A retrospective analysis of pediatric patients aged 11-17 years with POTS, who underwent autonomic testing at Nemours Children's Hospital in Orlando, Florida, was conducted. The patients were screened for anxiety, using the Severity Measure for Generalized Anxiety Disorder-Child Age 11-17 years (GAD-7) questionnaire, and depression, using PHQ-9 Modified for Adolescence (PHQ-A) for depression. The prevalence rates of anxiety and depression in the study cohort were compared to historical data from similar age groups in the existing literature. The study was approved by the Nemours Children's Hospital Institutional Review Board. RESULTS: The cohort comprised 27 children with POTS (26 females, age 15.8±1.6 years). Overall, 74% exhibited moderate-to-severe anxiety, depression, or both, with 44% having comorbid anxiety and depression. In total, 4/27 (14%) had pure depression and 4/27 (14%) had pure anxiety. Six patients had no depression or anxiety. On average, POTS symptoms began 1.9±1.3 years before diagnosis. Eleven patients took stable doses of psychotropic medications. After a follow-up period of 5.1±1.7 months of POTS therapy, seven patients had follow-up questionnaires. In 4/7 patients, the depression severity improved, and in 3/7 patients, the anxiety severity improved. Patients were not actively treated for depression and anxiety during this time. CONCLUSION: Anxiety and depression are prevalent among pediatric patients with POTS. While preliminary data suggests POTS therapy may alleviate these psychological symptoms, further longitudinal studies are warranted to explore the therapeutic impact in greater detail.

Co-occurrence of Attention-Deficit/Hyperactivity Disorder and Septo-Optic Dysplasia: A Neurodevelopmental Case Report.

Septo-optic dysplasia (SOD) is a rare congenital disorder characterized by optic nerve hypoplasia, brain midline structure anomalies, and hypothalamic-pituitary axis hypoplasia. This case report aims to highlight the association between SOD and neurodevelopmental disorders, focusing on attention-deficit/hyperactivity disorder (ADHD) in addition to the well-established link with autism spectrum disorder (ASD). A six-year-old male diagnosed with SOD presented with behavioral concerns, including attention and impulse control issues. A comprehensive psychological evaluation confirmed the diagnosis of ADHD and ruled out ASD. Ophthalmological assessments were integral to understanding the patient's condition. This case underscores the importance of recognizing neurodevelopmental disorders in individuals with SOD, with a particular focus on the less common association with ADHD. The co-occurrence of these conditions underscores the complexity of neurodevelopmental disorders and the need for comprehensive evaluation and management. Collaboration between ophthalmologists and mental health specialists is crucial for addressing the diverse needs of these patients. Early identification and intervention for ADHD are essential for optimal developmental outcomes. This case underscores the necessity for further research to elucidate the relationship between SOD and ADHD, emphasizing the importance of holistic patient care and interdisciplinary collaboration in managing individuals with SOD spectrum conditions.

Median Arcuate Ligament Syndrome in Children: A Single-Center Experience.

BACKGROUND: Data on median arcuate ligament syndrome (MALS) in children are scant. It is postulated that MALS can cause chronic abdominal pain. It is unclear what percentage of children with this condition are symptomatic and what comorbidities are associated with this syndrome. METHODS: In this retrospective study, data on consecutive patients in a single center diagnosed coincidentally with MALS during routine echocardiogram were reviewed. Symptom burden, comorbidities, and the effect of anthropometric indices on MALS were investigated. Descriptive statistics and nonparametric tests were used to describe the findings and to compare variables with normal distribution. RESULTS: Between 2013 and 2020, there were 82 children, 55 females (67%), mean age 13.9 ± 3.2 years, with MALS and complete record. Mean velocity across the stenotic area was 2.6 ± 0.4 m/s. Forty-six patients (57%) had abdominal pain. Age, gender, weight, body mass index (BMI), and Doppler velocity had no statistically significant influence on symptom occurrence. Conversely, patients with joint hypermobility and symptoms of orthostatic intolerance were more likely to have abdominal pain from MALS. Of 24 patients with joint hypermobility, 18 patients had abdominal pain (p=0.027). Thirty-eight patients with orthostatic intolerance (OI) with MALS complained of abdominal pain vs 13 patients with OI and no abdominal pain (p=<0.0001). CONCLUSION: Nearly half of patients with MALS had abdominal pain. Age, gender, weight, and the degree of stenosis had no statistically significant influence on symptom occurrence. OI, specifically postural orthostatic tachycardia syndrome (POTS), and joint hypermobility on exam predicted a higher propensity for abdominal pain in patients with MALS.

A Case of Hydroxychloroquine Toxicity as Evidenced by Visual Field Changes.

Hydroxychloroquine sulfate (Plaquenil®) is a disease-modifying anti-rheumatic drug (DMARD) utilized in the management of autoimmune diseases. While its immunomodulatory actions offer therapeutic benefits, a rare complication, hydroxychloroquine-induced retinal toxicity, poses a significant concern. We present the case of an 83-year-old patient with cutaneous lupus undergoing periodic hydroxychloroquine screening for eight years. Visual field changes consistent with retinal toxicity were observed. Chart review revealed subtle visual field depression two years prior. This highlights the importance of vigilance toward unexplained visual changes and subtle changes on ophthalmologic examination in hydroxychloroquine-treated patients. Our findings underscore the necessity of baseline and periodic ophthalmologic examinations with particular attention paid to visual field depression or deficit that might occur without macular changes. Additionally, we address the choice between red and white visual field testing. This case contributes to the understanding of hydroxychloroquine-induced retinal toxicity, emphasizing the importance of comprehensive ophthalmologic surveillance in long-term users.