Related resources
Full-text held externally
- PMID: 25085203
- UKPMCID: 25085203
- DOI: 10.1093/europace/euu084
Search for item elsewhere
University researcher(s)
Academic department(s)
Effects of human atrial ionic remodelling by β-blocker therapy on mechanisms of atrial fibrillation: a computer simulation.
Kharche, Sanjay R; Stary, Tomas; Colman, Michael A; Biktasheva, Irina V; Workman, Antony J; Rankin, Andrew C; Holden, Arun V; Zhang, Henggui
Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology. 2014;16(10):1524-33.
Access to files
Full-text and supplementary files are not available from Manchester eScholar. Full-text is available externally using the following links:
Full-text held externally
- PMID: 25085203
- UKPMCID: 25085203
- DOI: 10.1093/europace/euu084
Abstract
AIMS: Atrial anti-arrhythmic effects of β-adrenoceptor antagonists (β-blockers) may involve both a suppression of pro-arrhythmic effects of catecholamines, and an adaptational electrophysiological response to chronic β-blocker use; so-called 'pharmacological remodelling'. In human atrium, such remodelling decreases the transient outward (Ito) and inward rectifier (IK1) K(+) currents, and increases the cellular action potential duration (APD) and effective refractory period (ERP). However, the consequences of these changes on mechanisms of genesis and maintenance of atrial fibrillation (AF) are unknown. Using mathematical modelling, we tested the hypothesis that the long-term adaptational decrease in human atrial Ito and IK1 caused by chronic β-blocker therapy, i.e. independent of acute electrophysiological effects of β-blockers, in an otherwise un-remodelled atrium, could suppress AF. METHODS AND RESULTS: Contemporarily, biophysically detailed human atrial cell and tissue models were used to investigate effects of the β-blocker-based pharmacological remodelling. Chronic β-blockade remodelling prolonged atrial cell APD and ERP. The incidence of small amplitude APD alternans in the CRN model was reduced. At the 1D tissue level, β-blocker remodelling decreased the maximum pacing rate at which APs could be conducted. At the three-dimensional organ level, β-blocker remodelling reduced the life span of re-entry scroll waves. CONCLUSION: This study improves our understanding of the electrophysiological mechanisms of AF suppression by chronic β-blocker therapy. Atrial fibrillation suppression may involve a reduced propensity for maintenance of re-entrant excitation waves, as a consequence of increased APD and ERP.
Keyword(s)
Arrhythmia; Atrial fibrillation; Computer simulation; Ion channel; β-Blockers