Objectives: The goal of the present prospective study is to evaluate the impact of vagal excitation on ongoing atrial fibrillation (AF) during pulmonary vein (PV) isolation.
Background: The role of vagal tone in maintenance of AF is controversial in humans.
Methods: Twenty-five patients (18 with paroxysmal AF, 7 with chronic AF) were selected by occurrence of vagal excitation during AF (atrioventricular [AV] block: R-R interval >3 s) produced by PV isolation. Fibrillatory cycle length (CL) in the targeted PV and coronary sinus (CS) were determined before, during, and after vagal excitation. The CL was available at PV ostium during vagal excitation in 11 patients.
Results: Forty-eight episodes of vagal excitation were observed. During vagal excitation, CL abruptly decreased both in CS and PV (CS, 164 +/- 20 ms to 155 +/- 23 ms, p < 0.0001; PV, 160 +/- 22 ms to 143 +/- 28 ms, p < 0.0001), and both returned to the baseline value with resumption of AV conduction. The decrease in PVCL occurred earlier (2.5 +/- 1.5 s vs. 4.0 +/- 2.6 s, p < 0.01) and was of greater magnitude than that in CSCL (16 +/- 16 ms vs. 8 +/- 9 ms, p < 0.01). A sequential gradient of CL was observed from PV to PV ostium and CS during vagal excitation (138 +/- 29 ms, 149 +/- 24 ms, and 159 +/- 26 ms, respectively). The decrease in CL was significantly greater in paroxysmal than in chronic AF (CS, 11 +/- 9 ms vs. 5 +/- 7 ms, p < 0.05; PV, 23 +/- 25 ms vs. 8 +/- 14 ms, p < 0.05).
Conclusions: Vagal excitation is associated with shortening of fibrillatory CL. This occurs earlier in PV with a sequential gradient to PV ostium and CS, suggesting that vagal excitation enhances a driving role of PV.
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http://dx.doi.org/10.1016/j.jacc.2005.10.043 | DOI Listing |
Nat Metab
January 2025
Neuroscience Institute, College of Arts and Sciences, Georgia State University, Atlanta, GA, USA.
Interoception broadly refers to awareness of one's internal milieu. Although the importance of the body-to-brain communication that underlies interoception is implicit, the vagal afferent signalling and corresponding brain circuits that shape perception of the viscera are not entirely clear. Here, we use mice to parse neural circuits subserving interoception of the heart and gut.
View Article and Find Full Text PDFJ Electrocardiol
January 2025
Carver College of Medicine, University of Iowa Hospitals and Clinics, Iowa City, IA, United States of America.
Neurocardiology is a broad interdisciplinary specialty investigating how the cardiovascular and nervous systems interact. In this brief introductory review, we describe several key aspects of this interaction with specific attention to cardiovascular effects. The review introduces basic anatomy and discusses physiological mechanisms and effects that play crucial roles in the interaction of the cardiovascular and nervous systems, namely: the cardiac neuraxis, the taxonomy of the nervous system, integration of sensory input in the brainstem, influences of the autonomic nervous system (ANS) on heart and vasculature, the neural pathways and functioning of the arterial baroreflex, receptors and ANS effects in the walls of blood vessels, receptors and ANS effects in excitable cells in the heart, ANS effects on heart rate and sympathovagal balance, endo-epicardial inhomogeneity, ANS effects with a balanced vagal and sympathetic stimulation, sympathovagal interaction, arterial baroreflex, baroreflex sensitivity and heart rate variability, arrhythmias and the arterial baroreflex, the cardiopulmonary baroreflex, the exercise pressor reflex, exercise-recovery hysteresis, mental stress, cardiac-cardiac reflexes, the cardiac sympathetic afferent reflex (CSAR), and neuromodulation.
View Article and Find Full Text PDFCell Rep
December 2024
Department of Physiology and Pharmacology, Karolinska Institutet, Solna, Sweden; Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada. Electronic address:
Nociceptor neurons play a crucial role in maintaining the body's homeostasis by detecting and responding to potential environmental dangers. However, this function can be detrimental during allergic reactions, as vagal nociceptors contribute to immune cell infiltration, bronchial hypersensitivity, and mucus imbalance in addition to causing pain and coughing. Despite this, the specific mechanisms by which nociceptors acquire pro-inflammatory characteristics during allergic reactions are not yet fully understood.
View Article and Find Full Text PDFJ Cardiovasc Electrophysiol
January 2025
Division of Epidemiology, University of Utah School of Medicine, Salt Lake City, Utah, USA.
Introduction: Current guidelines recommend electrophysiological study (EPS) and ablation for primary treatment of supraventricular tachycardia (SVT), but there is little information to guide patient selection for the procedure. The purpose of this study was to identify preoperative features that would predict whether patients with signs or symptoms of tachycardia were likely to have SVT induced and ablated at EPS.
Methods: We performed a retrospective chart review of 1089 patients referred for EPS and ablation of SVT at 2 high volume centers.
bioRxiv
September 2024
Department of Physiology and Pharmacology, Karolinska Institutet. Sweden.
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