Suppressing Spiral And Turbulent Waves In Cardiac Tissues By Circularly Polarized Electric Fields

Spiral or turbulent waves in cardiac tissues may cause lethals, such as tachycardia or fibrillation. Clinically, arrhythmias can be terminated by globally resetting activity in cardiac tissues with a single high-voltage electric shock and eventually return to normal sinus rhythm. Although this approach is used routinely in emergency medicine, treatments are often associated with severe side effects. Besides, there is also a method to effectively control the arrhythmias which installs an artificial cardiac pacemaker in vivo. This approach is mainly implant electronic treatment equipment in vivo, and the pulse generator can issue a series of regular electrical impulses to adjust the speed of cardiac pacing. However, this instrument is currently applicable to more slowly arrhythmias, and also difficult to remove for some anchored spiral waves.Hence, more new arrhythmias treatments have been continuously raised and one of them called far field stimulation or wave emission from heterogeneities (WEH) has been sparked many discussions. This approach is based on the fact that, by the application of a uniform electric field (UEF) to a whole piece of tissue, de-polarizations and hyper-polarizations could be induced near obstacles (conductivity heterogeneities). If the electric strength exceeds some threshold, obstacles can act as virtual electrodes or second sources. After each pulse, the area that is activated increases, indicating progressive synchronization of the myocardium; fibrillation then terminates and normal sinus rhythm can resume. The method is applied external electric field, the required voltage is low which is less damage to the human body, and can effectively remove the anchored spiral waves and terminate fibrillation. However, this method is less success rate and small applications to unpin the anchored spiral waves. Besides, this method can only emit waves locally near obstacles in turbulent waves and thereby requires multiple obstacles to globally synchronize myocardium and thus to terminate fibrillation.Here we provide a new approach using WEH induced by circularly polarized electric field (CPEF), which also can induce de-polarizations and hyper-polarizations near obstacles to unpin rotating spiral waves and terminate turbulence in cardiac tissues. To unpin the rotating spiral waves, this method has higher success rate and larger application scope than UEF, even with a lower voltage. And to terminate turbulence, even with an obstacle, it can also emit waves in the turbulent waves, and form the circular wave train to suppress spiral turbulence. Therefore, we can include that far field simulation with CPEF can be better used to terminate arrhythmias.