title: Pacemaker interactions induce reentrant wave dynamics in engineered cardiac culture.
abstract: Pacemaker interactions can lead to complex wave dynamics seen in certain types of cardiac arrhythmias. We use experimental and mathematical models of pacemakers in heterogeneous excitable media to investigate how pacemaker interactions can be a mechanism for wave break and reentrant wave dynamics. Embryonic chick ventricular cells are cultured in vitro so as to create a dominant central pacemaker site that entrains other pacemakers in the medium. Exposure of those cultures to a potassium channel blocker, E-4031, leads to emergence of peripheral pacemakers that compete with each other and with the central pacemaker. Waves emitted by faster pacemakers break up over the slower pacemaker to form reentrant waves. Similar dynamics are observed in a modified FitzHugh-Nagumo model of heterogeneous excitable media with two distinct sites of pacemaking. These findings elucidate a mechanism of pacemaker-induced reentry in excitable media.
authors.affiliation: Department of Physiology, McGill University, 3655 Promenade Sir William Osler, Montreal, Quebec H3G 1Y6, Canada.
authors.forename: Bartłomiej
authors.initials: B
authors.lastname: Borek
authors.forename: T K
authors.initials: TK
authors.lastname: Shajahan
authors.forename: James
authors.initials: J
authors.lastname: Gabriels
authors.forename: Alex
authors.initials: A
authors.lastname: Hodge
authors.forename: Leon
authors.initials: L
authors.lastname: Glass
authors.forename: Alvin
authors.initials: A
authors.lastname: Shrier
mesh_terms: D000818:Animals; D001145:Arrhythmias, Cardiac / Q000503:physiopathology*; D002642:Chick Embryo; D006321:Heart / Q000187:drug effects / Q000503:physiopathology*; D008955:Models, Cardiovascular; D010138:Pacemaker, Artificial; D010880:Piperidines / Q000494:pharmacology; D011725:Pyridines / Q000494:pharmacology; D046509:Tissue Culture Techniques / Q000379:methods*; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D010880:Piperidines; D011725:Pyridines; C063968:E 4031