Objectives: This study was conducted to simulate sleep apnea-induced atrial fibrillation (AF) in an experimental model and to determine whether neural ablation will prevent AF.
Background: An increasing number of clinical reports have associated sleep apnea and AF, and many possible mechanisms responsible for this relationship have been proposed.
Methods: Thirty dogs anesthetized with Na-pentobarbital were ventilated by a positive pressure respirator. Protocol 1 (n = 14): After a right thoracotomy, atrial and pulmonary vein programmed pacing at 2x and 4x threshold determined the shortest atrial refractory period. Obstructive apnea was induced by turning off the respirator during end expiration for 2 min. During apnea, programmed pacing was performed with S1-S2 = 5 to 10 ms earlier than the atrial refractory period. Neural activity was monitored from the ganglionated plexi (GP) adjacent to the right pulmonary veins. Protocol 2 (n = 16): Electrical stimulation identified the GP at the right pulmonary artery (RPA). Programmed pacing was again instituted, below atrial refractory period, during 2 min of apnea. After radiofrequency ablation of the RPA GP, continuous programmed pacing was again repeated during 2 min of apnea. In 5 dogs, blood gases were determined at baseline and at 2 min of apnea.
Results: Protocol 1: During apnea, S1-S2 induced AF within 85 +/- 38 s (9 of 10). In 1 case, AF occurred spontaneously at 1 min 36 s of apnea. Recorded GP neural activity progressively increased before AF onset. Systolic but not diastolic blood pressure rose significantly before AF (149 +/- 26 mm Hg to 193 +/- 38 mm Hg, p < 0.05). In 4 dogs, autonomic blockade prevented apnea-induced AF. Protocol 2: AF induced by pacing occurred in 8 of 11 dogs within the 2-min period of apnea, before neural ablation. After ablation, 0 of 6 showed AF during 2 min of apnea (p = 0.009).
Conclusions: This experimental model of apnea shows a reproducible incidence of AF. After neural ablation of the RPA GP or autonomic blockade, AF inducibility was significantly inhibited.
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http://dx.doi.org/10.1016/j.jacc.2009.09.014 | DOI Listing |
Sleep Breath
January 2025
Department of Otolaryngology, The First Affiliated Hospital of Heilongjiang University of Traditional Chinese Medicine, Harbin, 150040, China.
Background: This study aimed to investigate the association between Obstructive Sleep Apnea (OSA) and Tinnitus using NHANES data from 2005 to 2020.
Methods: This study analyzed data from NHANES (National Health and Nutrition Examination Surveys) conducted between 2005 and 2020, and included 4871 participants aged 16 or older. OSA was assessed using the Multivariate Apnea Prediction Index and the variables from the National Health and Nutrition Examination Survey.
Front Physiol
January 2025
Environmental Physiology Group, Department of Health Sciences, Mid Sweden University, Östersund, Sweden.
Background And Aim: Hyperventilation before breath-hold diving (freediving) is widely accepted as a risk factor for hypoxic syncope or blackout (BO), but there is no practical way to address it before dives. This study explores the feasibility of using a force sensor to predict end-tidal carbon dioxide ( CO) to assess hyperventilation in freedivers.
Methods And Results: Twenty-one freedivers volunteered to participate during two national competitions.
Sleep Breath
January 2025
Akureyri Junior College, Akureyri, Iceland.
Objectives: Sleep is often compromised in adolescents, affecting their health and quality of life. This pilot-study was conducted to evaluate if implementing brief-behavioral and sleep-hygiene education with mindfulness intervention may positively affect sleep-health in adolescents.
Method: Participants in this community-based non-randomized cohort-study volunteered for intervention (IG)- or control-group (CG).
J Pineal Res
January 2025
Institute of Aerospace Medicine, German Aerospace Center (DLR), Cologne, Germany.
Circadian clocks in the body drive daily cycles in physiology and behavior. A master clock in the brain maintains synchrony with the environmental day-night cycle and uses internal signals to keep clocks in other tissues aligned. Work in cell cultures uncovered cyclic changes in tissue oxygenation that may serve to reset and synchronize circadian clocks.
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.
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