A number of different types of rapid cardiac rhythm disorders, including atrial and ventricular fibrillation, are likely caused by several, randomly rotating, action potential waves. Thus, an electrical pacing therapy whose effectiveness is based on being delivered with a particular timing relative to one of these waves is unlikely to be useful in terminating the remaining waves. Here we develop pacing protocols that are designed to terminate rotating waves independently of when the sequences of stimuli are imposed or where each wave is in its rotation at the time the sequences are initiated. These protocols are delivered as far-field stimuli, and therefore are capable of simultaneously influencing all the waves present. The pacing intervals for these protocols are, in general, of unequal duration, and are determined through examination of the dynamics of action potential propagation in a one-dimensional ring model. Series of two or three stimuli with inter-stimulus intervals chosen in this way are shown to be effective in terminating these waves over a wide range of ring circumferences and action potential dynamical parameters. Stimulus sequences of this type may form the basis for developing new defibrillation protocols to test in experiments or more realistic models of the electrical heart.
展开▼
