In experiments on the heart of the cod Gadus morhua and frog Rana temporaria in situ, studies have been made of changes in the heart rate induced by stimulation of the vagal nerve by single brief bursts delivered at various intervals after P wave of the ECG. Certain differences were found in changes of the heart rate between these animals. In the cod, maximum chronotropic effect was equal to 65% of the duration of initial cardiac cycle, the latency of this effect being equal to 290 ms; in the frog, corresponding figures were 12-13% and approximately 940 ms. The duration of negative chronotropic effect in the heart of the cod was equal to 700 ms, that of the frog--to 2.700 ms. Functional role of these differences is discussed in relation to the problem of the development of parasympathetic regulation of the heart rate in phylogenesis of vertebrates.
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Open Heart
November 2024
Cardiothoracic Department, Santa Maria della Misericordia University Hospital, Udine, Italy
Background: Ventricular arrhythmias (VAs) frequently occur in the acute phase of myocarditis. Possible arrhythmic recurrences and the risk of sudden cardiac death (SCD) in this setting are reasons for concern, and limited data have been published to guide clinical management of these patients. The aim of the present paper is to report the incidence of major arrhythmic events, defined as sustained VA, SCD and appropriate implantable cardiac-defibrillator (ICD) treatment, in patients with acute myocarditis and ventricular arrhythmic phenotype.
View Article and Find Full Text PDFFront Neurol
January 2025
Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD, United States.
Background: Postural Orthostatic Tachycardia Syndrome (POTS) is a complex form of dysautonomia that presents with abnormal autonomic reflexes upon standing, leading to symptoms such as lightheadedness, tachycardia, fatigue, and cognitive impairment. The COVID-19 pandemic has brought renewed attention to POTS due to its overlap with post-acute sequelae of COVID-19 (PASC). Studies have found that a substantial percentage of COVID-19 survivors exhibit symptoms resembling POTS, elevating POTS diagnoses to previously unseen levels.
View Article and Find Full Text PDFFront Neurol
January 2025
ARID Laboratory, Department of Pediatrics, College of Medicine, University of Arizona, Tucson, AZ, United States.
Introduction: People with hypermobile Ehlers-Danlos syndrome (hEDS) experience multisystemic dysfunction with varying severity and unpredictability of flare occurrence. Cohort studies suggest that individuals with hEDS have a higher risk for autonomic dysfunction. The gold standard for assessing autonomic function, clinically, is the heart rate variability (HRV) assessment from 24-h Holter monitor electrocardiogram data, but this is expensive and can only be performed in short durations.
View Article and Find Full Text PDFLancet Reg Health West Pac
February 2025
Department of Endocrinology and Metabolism, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Clinical Center for Diabetes, Shanghai Key Clinical Center for Metabolic Disease, Shanghai, China.
Background: To date, comprehensive data on the distribution of chronic kidney disease (CKD), the most prevalent comorbidity in diabetes, among Chinese adults with diabetes is lacking. Additionally, research gaps exist in understanding the association between CKD and cardiovascular health (CVH), an integrated indicator of lifestyle and metabolic control, within a nationwide sample of Chinese adults with diabetes.
Methods: A nationally community-based cross-sectional survey was conducted in 2018-2020.
Cureus
January 2025
Graduate School of Medicine, Mie University, Tsu, JPN.
Purpose In recent years, research on caregivers has highlighted the importance of integrating advanced technologies, such as wearable devices. Furthermore, when investigating the characteristics of persons with dementia (PWD), comparative analyses should be conducted based on the presence or absence of the condition. We aimed to elucidate the relationship between caregivers' subjective burdens, tasks, and heart rate (HR) using wearable sensors to objectively assess the health status of caregivers of PWD and older adults requiring long-term care.
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