The presence of three-dimensional rotating action potential waves, called scroll waves, in the heart causes ventricular fibrillation. Recently, there has been interest in developing low-energy methods, consisting of applying an electric field to terminate these waves, as a means of defibrillation. The success of these methods often depends on the orientation of the waves. We present computer simulations of a method that applies multiple electrical fields in a hemispherical shell system representative of the ventricles of the heart. Scroll waves in this system persist when the filament (the curve around which the wave rotates) connects the inside and outside surfaces. Our scheme for applying electric fields aims to disconnect these filaments from the surfaces. Once the filaments no longer connect the inside and outside surfaces, they contract and disappear, terminating the scroll wave. Importantly, as opposed to most existing schemes, the idea on which this scheme is based is applicable irrespective of how many scroll waves are present, where they are located, or where they are in their rotation. We discuss the success of this scheme both for different numbers of waves and for different wave orientations and present potential failure mechanisms. The effects of other conditions, such as the stability of the waves and heart geometry, remain to be studied. In the future, the presented low-energy method for termination of scroll waves may be a useful means of cardiac defibrillation.
Library of Congress Subject Headings
Electric countershock--Computer simulation
Applied and Computational Mathematics (MS)
Department, Program, or Center
School of Mathematical Sciences (COS)
Wheeler, Kayleigh, "New concepts for use in low-energy cardiac defibrillation" (2017). Thesis. Rochester Institute of Technology. Accessed from
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