title: Advantage of four-electrode over two-electrode defibrillators.
abstract: Defibrillation is the standard clinical treatment used to stop ventricular fibrillation. An electrical device delivers a controlled amount of electrical energy via a pair of electrodes in order to reestablish a normal heart rate. We propose a technique that is a combination of biphasic shocks applied with a four-electrode system rather than the standard two-electrode system. We use a numerical model of a one-dimensional ring of cardiac tissue in order to test and evaluate the benefit of this technique. We compare three different shock protocols, namely a monophasic and two types of biphasic shocks. The results obtained by using a four-electrode system are compared quantitatively with those obtained with the standard two-electrode system. We find that a huge reduction in defibrillation threshold is achieved with the four-electrode system. For the most efficient protocol (asymmetric biphasic), we obtain a reduction in excess of 80% in the energy required for a defibrillation success rate of 90%. The mechanisms of successful defibrillation are also analyzed. This reveals that the advantage of asymmetric biphasic shocks with four electrodes lies in the duration of the cathodal and anodal phase of the shock.
authors.affiliation: Physics & Applied Mathematics Department, Navarra University, E-31080 Pamplona, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Bragard
authors.affiliation: Physics & Applied Mathematics Department, Navarra University, E-31080 Pamplona, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Šimić
authors.affiliation: Instituto de Alta Investigación, Universidad de Tarapacá, Casilla 7D, Arica, Chile.|SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom.
authors.forename: D
authors.initials: D
authors.lastname: Laroze
authors.affiliation: Physics & Applied Mathematics Department, Navarra University, E-31080 Pamplona, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Elorza