title: Shock-induced termination of reentrant cardiac arrhythmias: comparing monophasic and biphasic shock protocols.
abstract: In this article, we compare quantitatively the efficiency of three different protocols commonly used in commercial defibrillators. These are based on monophasic and both symmetric and asymmetric biphasic shocks. A numerical one-dimensional model of cardiac tissue using the bidomain formulation is used in order to test the different protocols. In particular, we performed a total of 4.8 × 10(6) simulations by varying shock waveform, shock energy, initial conditions, and heterogeneity in internal electrical conductivity. Whenever the shock successfully removed the reentrant dynamics in the tissue, we classified the mechanism. The analysis of the numerical data shows that biphasic shocks are significantly more efficient (by about 25%) than the corresponding monophasic ones. We determine that the increase in efficiency of the biphasic shocks can be explained by the higher proportion of newly excited tissue through the mechanism of direct activation.
authors.affiliation: Department of Physics & Applied Math., University of Navarra, Pamplona, Spain.
authors.forename: Jean
authors.initials: J
authors.lastname: Bragard
authors.affiliation: Department of Physics & Applied Math., University of Navarra, Pamplona, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Simic
authors.affiliation: Department of Physics & Applied Math., University of Navarra, Pamplona, Spain.
authors.forename: Jorge
authors.initials: J
authors.lastname: Elorza
authors.affiliation: School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors.forename: Roman O
authors.initials: RO
authors.lastname: Grigoriev
authors.affiliation: School of Mathematical Sciences, Rochester Institute of Technology, Rochester, New York 14623, USA.
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Cherry
authors.affiliation: University of Prince Edward Island, Charlottetown C1A 4P3, Canada.
authors.forename: Robert F
authors.initials: RF
authors.lastname: Gilmour
authors.affiliation: School of Mathematical Sciences, Rochester Institute of Technology, Rochester, New York 14623, USA.
authors.forename: Niels F
authors.initials: NF
authors.lastname: Otani
authors.affiliation: School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors.forename: Flavio H
authors.initials: FH
authors.lastname: Fenton
mesh_terms: D001145:Arrhythmias, Cardiac / Q000503:physiopathology* / Q000628:therapy; D004554:Electric Countershock; D006801:Humans; D008955:Models, Cardiovascular; D009206:Myocardium