Sympathetic and parasympathetic activity was evaluated in ten healthy controls, nine asymptomatic, untreated asthmatic subjects and ten asthmatic patients during treatment for acute asthma, by measurement of the variation in resting heart rate using frequency spectrum analysis. Heart rate was recorded by ECG and respiratory rate by impedance plethysmography. Spectral density of the beat-to-beat heart rate was measured within the low frequency band 0.04 to 0.10 Hz (low frequency power) modulated by sympathetic and parasympathetic activity, and within a 0.12 Hz band width at the respiratory frequency mode (respiratory frequency power) modulated by parasympathetic activity. Acute asthmatics had higher heart rates than either of the other two groups; this was probably related to the effects of beta-adrenoceptor agonist medication. Sympathetically mediated heart rate variability (normalized low frequency power) was significantly lower in both asymptomatic (p less than 0.002) and acute (p less than 0.02) asthma subjects compared to controls. This is consistent with altered sympathetic/parasympathetic regulation of heart rate in subjects with bronchial asthma.
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http://dx.doi.org/10.1007/BF01819665 | DOI Listing |
Am J Physiol Heart Circ Physiol
January 2025
Comenius University Bratislava, Faculty of Pharmacy, Department of Pharmacology and Toxicology, Bratislava, Slovakia.
Cholinesterase (ChE) inhibitors are under consideration to be used in the treatment of cardiovascular pathologies. A prerequisite to advancing ChE inhibitors into the clinic is their thorough characterization in the heart. The aim here was to provide a detailed analysis of cardiac ChE to understand their molecular composition, localization, and physiological functions.
View Article and Find Full Text PDFUltrasound J
January 2025
Health Sciences North Research Institute, Sudbury, ON, Canada.
The duration of mechanical systole-also termed the flow time (FT) or left ventricular ejection time (LVET)-is measured by Doppler ultrasound and increasingly used as a stroke volume (SV) surrogate to guide patient care. Nevertheless, confusion exists as to the determinants of FT and a critical evaluation of this measure is needed. Using Doppler ultrasound of the left ventricular outflow tract velocity time integral (LVOT VTI) as well as strain and strain rate echocardiography as grounding principles, this brief commentary offers a model for the independent influences of FT.
View Article and Find Full Text PDFClin Otolaryngol
January 2025
Department of Otorhinolaryngology-Head and Neck Surgery, Linkou Chang Gung Memorial Hospital, Taoyuan, Taiwan.
Introduction: Obstructive sleep apnoea (OSA) in children is associated with numerous adverse outcomes, including elevated blood pressure. While the associations between OSA, obesity, and autonomic dysfunction are recognised, the precise mechanisms linking these factors and their relationship with elevated blood pressure in children remain unclear.
Methods: This retrospective case series included 76 children with OSA.
Artif Organs
January 2025
Division of Cardiology, Department of Medicine, Columbia University College of Physicians and Surgeons and NewYork-Presbyterian Hospital, New York, New York, USA.
Background: GLP-1 RAs improve cardiometabolic outcomes in obese, diabetic, and heart failure patients. Data on the safety and efficacy of GLP-1 RA in advanced heart failure with durable LVAD is limited.
Objectives: To assess the safety and efficacy of GLP-1 RA in durable LVAD patients.
J Vet Intern Med
January 2025
Boehringer Ingelheim Pharma GmbH & Co., Ingelheim, Germany.
Background: Myxomatous mitral valve disease (MMVD) is frequently diagnosed in small breed dogs. Pimobendan oral solution has been developed to improve dosing accuracy in small and toy breed dogs.
Hypothesis/objectives: Demonstrate bioequivalence of pimobendan oral solution with pimobendan chewable tablets using a pharmacokinetic and a pharmacodynamic study in healthy purpose bred dogs.
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