Elhacene Matene1, Alain Vinet1, Vincent Jacquemet2. 1. Centre de Recherche, Hôpital du Sacré-Coeur de Montréal, 5400, boul. Gouin Ouest, Montreal, QC, Canada H4J 1C5 Département de Physiologie Moléculaire et Intégrative, Institut de Génie Biomédical, Université de Montréal, Montreal, QC, Canada H3T 1J4. 2. Centre de Recherche, Hôpital du Sacré-Coeur de Montréal, 5400, boul. Gouin Ouest, Montreal, QC, Canada H4J 1C5 Département de Physiologie Moléculaire et Intégrative, Institut de Génie Biomédical, Université de Montréal, Montreal, QC, Canada H3T 1J4 vincent.jacquemet@umontreal.ca.
Abstract
AIM: The autonomic nervous system modulates atrial activity, notably through acetylcholine (ACh) release. This time-dependent action may alter the dynamics of atrial arrhythmia. Our aim is to investigate in a computer model the changes induced by ACh release and degradation on the dynamical regime of a reentry. METHODS AND RESULTS: A functional reentry was simulated in a 10 × 5 cm(2) two-dimensional tissue with canine atrial membrane kinetics including an ACh-dependent K(+) current. The local ACh concentration was altered over time in a circular region following a predefined spatiotemporal profile (ACh release and degradation) characterized by its maximum ACh level, time constant of release/degradation, and diameter of the region. Phase singularities were tracked to monitor the complexity of the dynamics. Four scenarios were identified: (i) the original reentry remained stable; (ii) repolarization gradients induced by ACh release caused wavebreaks, resulting in a transient complex dynamics that spontaneously converted to a single stable reentry; (iii) the reentry self-terminated through wavebreaks and wavefront interactions; (4) wavebreaks led to a complex dynamics that converted to two or three reentries that remained stable after ACh degradation. Higher ACh level, short ACh release time constant, larger heterogeneous region, and short distance between the heterogeneous region and the spiral tip were associated with higher occurrence of ACh-induced wavebreaks. CONCLUSION: Variation of ACh concentration over time may modulate the complexity of atrial arrhythmias. Published on behalf of the European Society of Cardiology. All rights reserved.
AIM: The autonomic nervous system modulates atrial activity, notably through acetylcholine (ACh) release. This time-dependent action may alter the dynamics of atrial arrhythmia. Our aim is to investigate in a computer model the changes induced by ACh release and degradation on the dynamical regime of a reentry. METHODS AND RESULTS: A functional reentry was simulated in a 10 × 5 cm(2) two-dimensional tissue with canine atrial membrane kinetics including an ACh-dependent K(+) current. The local ACh concentration was altered over time in a circular region following a predefined spatiotemporal profile (ACh release and degradation) characterized by its maximum ACh level, time constant of release/degradation, and diameter of the region. Phase singularities were tracked to monitor the complexity of the dynamics. Four scenarios were identified: (i) the original reentry remained stable; (ii) repolarization gradients induced by ACh release caused wavebreaks, resulting in a transient complex dynamics that spontaneously converted to a single stable reentry; (iii) the reentry self-terminated through wavebreaks and wavefront interactions; (4) wavebreaks led to a complex dynamics that converted to two or three reentries that remained stable after ACh degradation. Higher ACh level, short ACh release time constant, larger heterogeneous region, and short distance between the heterogeneous region and the spiral tip were associated with higher occurrence of ACh-induced wavebreaks. CONCLUSION: Variation of ACh concentration over time may modulate the complexity of atrial arrhythmias. Published on behalf of the European Society of Cardiology. All rights reserved.
Authors: Jason D Bayer; Bastiaan J Boukens; Sébastien P J Krul; Caroline H Roney; Antoine H G Driessen; Wouter R Berger; Nicoline W E van den Berg; Arie O Verkerk; Edward J Vigmond; Ruben Coronel; Joris R de Groot Journal: Front Physiol Date: 2019-09-04 Impact factor: 4.566
Authors: Caroline H Roney; Marianne L Beach; Arihant M Mehta; Iain Sim; Cesare Corrado; Rokas Bendikas; Jose A Solis-Lemus; Orod Razeghi; John Whitaker; Louisa O'Neill; Gernot Plank; Edward Vigmond; Steven E Williams; Mark D O'Neill; Steven A Niederer Journal: Front Physiol Date: 2020-09-16 Impact factor: 4.566