Background: Changes in autonomic regulation of the heart may be responsible for the occurrence of arrhythmias. Although a decrease in 24-hour heart rate variability is a strong predictor of subsequent arrhythmias in patients with heart disease, many questions remain unanswered concerning changes in heart rate and heart rate variability in the minutes or hours preceding an arrhythmia. The aim of our study was to analyze changes in heart rate and heart rate variability occurring during the 90 minutes preceding an arrhythmia, in patients with coronary heart disease and an implantable defibrillator.
Materials And Methods: Thirty-eight patients, with a total of 93 episodes of ventricular arrhythmia, were included in the study. Heart rate and heart rate variability were measured in three 30-minute and five 2-minute periods preceding the arrhythmia. Heart rate variability was assessed using measurements of Poincaré plots.
Results: The results show a gradual increase in heart rate before the arrhythmia, from 73+/-13/min, to 75+/-14/min, and finally 78+/-15/min in the 90 minutes preceding the arrhythmia (P<0.05).
Conclusion: Measurements of Poincaré plots showed a significant increase in their length and no significant change in their width. These results suggest that sympathetic activation is the predominant change in autonomic nervous system before a ventricular arrhythmia in patients with coronary heart disease. This change may occur as early as one hour and a half before the arrhythmia.
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http://dx.doi.org/10.1046/j.1542-474x.2003.08302.x | DOI Listing |
Sports Med Open
January 2025
Department of Health Promotion, Faculty of Medical and Health Sciences, School of Public Health, Tel-Aviv University, Tel-Aviv, Israel.
Background: Studies on rest durations during high-intensity interval training (HIIT) often compare fixed and self-selected (SS) rest allocation approaches. Frequently, the rest duration under SS conditions is unlimited, leading to inconsistent total rest durations compared to fixed rest conditions. To address this limitation, we recently compared fixed and SS rest conditions during cycling HIIT sessions, while keeping the total rest duration equivalent.
View Article and Find Full Text PDFPediatr Surg Int
January 2025
Department of Neonatology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China.
Objective: To analyze the clinical characteristics and available treatment strategies for reoperation of neonatal high jejunal atresia, and recommend preventive measures to reduce the reoperation rate of high jejunal atresia.
Methods: The clinical data of 16 children with high jejunal atresia who underwent reoperation in the Neonatal Surgery Department at Children's Hospital of Zhejiang University School of Medicine from January 2018 to January 2023 were retrospectively analyzed.
Results: Among the 16 unplanned reoperations, 7 (43.
Ciprofol, a novel γ-aminobutyric acid receptor agonist, outperforms propofol with minimal cardiovascular effects, higher potency, reduced injection pain, and a broader safety margin. Despite these advantages, ciprofol's clinical research is still emerging. This study compares the median effective dose (ED) and adverse reactions of ciprofol and propofol, in conjunction with sufentanil, for suppressing cardiovascular responses during tracheal intubation.
View Article and Find Full Text PDFActa Paediatr
January 2025
Department of Neonatology, University Children's Hospital Basel UKBB, University of Basel, Basel, Switzerland.
Aim: We evaluated whether sample entropy of heart rate time series could serve as a biomarker for guiding caffeine cessation in preterm infants treated for apnoea of prematurity (AOP). We also assessed associations of sample entropy with weeks of gestation, clinical morbidity, AOP frequency and caffeine reinitiation.
Methods: We conducted a prospective single-centre study at the University Children's Hospital Basel, Switzerland, from July 2019 to June 2020.
Korean Circ J
January 2025
Imaging Department, Harefield Hospital, Royal Brompton and Harefield Hospitals, Harefield, United Kingdom.
Stress echocardiography has evolved from the sole assessment of regional wall motion abnormalities (RWMAs) to the ABCDE protocol, as recommended by the recent clinical consensus statement from the European Association of Cardiovascular Imaging, reflecting the need for a more systematic patient assessment. Steps A, B, C, D, and E assess RWMAs, lung B-lines, left ventricular contractile reserve, coronary flow velocity reserve (CFVR) in mid-distal left anterior descending artery, and heart rate reserve, respectively. Impairment of CFVR is considered as the earliest abnormality in the ischaemic cascade.
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