#Da bei zhou scroll series
Pinning is believed to play a crucial role in maintaining abnormal high frequency heart rhythms, including ventricular tachycardia and fibrillation, the main causes of sudden cardiac death 4, 5.īetter than the traditional but side-effect therapy of applying a high-voltage electric shock globally, the effect of unpinning by a series of electric pulses, i.e. Spiral and scroll waves can also be pinned (anchored) to localized heterogeneities, giving rise to sustained periodic or quasiperiodic activity 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24. Scroll waves are three-dimensional (3D) extensions of spiral waves, which rotate around one-dimensional singularities known as their filaments 6, 7, 8, 9, 10, 11, 12. Spiral waves are typical self-organized structures that exist in various systems including chemical media 1, 2, aggregations of Dictyostelium discoideum amoebae 3, and cardiac tissues 4, 5. We hope this remarkable ability of CPEF can provide a better alternative to terminate arrhythmias caused by pinned scroll waves.
Such higher-frequency spherical waves induced by CPEF can be used to drive the pinned scroll wave out of the cardiac systems. However, only CPEF can induce spherical waves with frequencies higher than that of the pinned scroll wave. We find that spherical waves can be induced from the heterogeneities by these electric fields in initially quiescent excitable media. In this article, we investigate in detail the removal of pinned scroll waves in a generic model of 3D excitable media using PDCEF, AC electric field (ACEF) and CPEF, respectively. Nevertheless, the unpinning of scroll waves in three-dimensional (3D) cardiac systems is much more difficult than that of spiral waves in 2D cardiac systems, and there are few reports on the removal of pinned scroll waves in 3D cardiac tissues by electric fields. To unpin these life-threatening spiral waves, methods of wave emission from heterogeneities (WEH) induced by low-voltage pulsed DC electric fields (PDCEFs) and circularly polarized electric fields (CPEFs) have been used in two-dimensional (2D) cardiac tissues. Spirals or scroll waves pinned to heterogeneities in cardiac tissues may cause lethal arrhythmias.
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