A Theory of Unpinning of Spiral Waves using Rotating Electric Fields

<p>Spiral waves pinned to obstacles cause self-perpetuating abnormal activation in the heart leading to life-threatening cardiac arrhythmias. To bring the heart back to its normal rhythm, the pinned spirals have to be eliminated. Apart from globally resetting shocks, pulsed and rotating electric fields are known to unpin the spirals using the method of wave emission from heterogeneties, with much lower voltage. Here, we provide a robust mechanism for termination of the pinned spiral waves using a rotating electric field. We show that the termination always happens within the first rotation of the electric field. For a given obstacle size, there exists a threshold time period of rotating field below which the spiral can always be terminated. Our analytical formulation accurately predicts this threshold and explains the absence of traditional unpinning window with the rotating electric field. Since the rotating electric field requires much lower field strength, this study may influence future low-energy defibrillation techniques.</p>