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Updated: Jul 16, 2026
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Estimating Bilateral Atrial Function by Cardiovascular Magnetic Resonance Feature Tracking in Patients with Paroxysmal Atrial Fibrillation
Published on: July 20, 2022
Autonomic nerve activity and atrial fibrillation
1Division of Cardiology, Department of Medicine, Cedars-Sinai Medical Center and David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA. chenpp@iupui.edu
Heart Rhythm
|March 6, 2007
Summary
Autonomic nervous system (ANS) activity, involving sympathetic and parasympathetic nerves, is crucial for paroxysmal atrial fibrillation (PAF) onset. Modulating cardiac ANS activity may offer new therapeutic strategies for atrial fibrillation control.
Area of Science:
- Cardiology
- Neuroscience
- Physiology
Background:
- Autonomic nervous system (ANS) activity plays a significant role in the induction of paroxysmal atrial fibrillation (PAF).
- Both sympathetic and parasympathetic nervous systems are implicated in mediating PAF.
- Heart rate variability analyses indicate sympathovagal imbalance precedes PAF episodes.
Purpose of the Study:
- To review the importance of ANS activity in PAF induction.
- To explore the mechanisms by which ANS activation contributes to PAF.
- To discuss potential therapeutic strategies targeting the cardiac ANS for AF control.
Main Methods:
- Analysis of clinical studies and heart rate variability.
- Review of animal experiments and in vitro studies.
- Examination of canine models of PAF and nerve activity recording.
Main Results:
- ANS activation prolongs intracellular calcium transients (sympathetic) and shortens action potential duration (parasympathetic), facilitating triggered activity.
- Spontaneous sarcoplasmic reticulum calcium release underlies focal discharges in canine pulmonary veins during sympathetic stimulation.
- Simultaneous sympathovagal discharges precede PAF onset in canine models.
Conclusions:
- ANS activity and intracellular calcium dynamics are critical in PAF development.
- Vagal denervation can enhance pulmonary vein ablation efficacy.
- Targeting cardiac ANS activity presents novel therapeutic avenues for atrial fibrillation management.
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