Simulation of ectopic pacemakers in the heart: multiple ectopic beats generated by reentry inside fibrotic regions

The inclusion of nonconducting media, mimicking cardiac fibrosis, in two models of cardiac tissue produces the formation of ectopic beats. The fraction of nonconducting media in comparison with the fraction of healthy myocytes and the topological distribution of cells determines the probability of e...

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Detalles Bibliográficos
Autores: Gouvêa de Barros, Bruno, Weber dos Santos, Rodrigo, Lobosco, Marcelo, Alonso Muñoz, Sergio|||0000-0002-3989-8757
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/78847
Acceso en línea:https://hdl.handle.net/2117/78847
https://dx.doi.org/10.1155/2015/713058
Access Level:acceso abierto
Palabra clave:Medical electronics
Electronics in cardiology
Cardiac arrhythmia
Ectopic beats
cardiac modeling
complex fractionated atrial electrograms
Electrònica mèdica
Electrònica en cardiologia
Àrees temàtiques de la UPC::Enginyeria biomèdica::Electrònica biomèdica::Electrònica en cardiologia
Descripción
Sumario:The inclusion of nonconducting media, mimicking cardiac fibrosis, in two models of cardiac tissue produces the formation of ectopic beats. The fraction of nonconducting media in comparison with the fraction of healthy myocytes and the topological distribution of cells determines the probability of ectopic beat generation. First, a detailed subcellular microscopic model that accounts for the microstructure of the cardiac tissue is constructed and employed for the numerical simulation of action potential propagation. Next, an equivalent discrete model is implemented, which permits a faster integration of the equations. This discrete model is a simplified version of the microscopic model that maintains the distribution of connections between cells. Both models produce similar results when describing action potential propagation in homogeneous tissue; however, they slightly differ in the generation of ectopic beats in heterogeneous tissue. Nevertheless, both models present the generation of reentry inside fibrotic tissues. This kind of reentry restricted to microfibrosis regions can result in the formation of ectopic pacemakers, that is, regions that will generate a series of ectopic stimulus at a fast pacing rate. In turn, such activity has been related to trigger fibrillation in the atria and in the ventricles in clinical and animal studies.