Wave emission from heterogeneities with changing boundary curvature and orientation by a circularly polarized electric field in cardiac tissues

In hearts, complex spatial-temporal patterns of action potential waves may cause life-threatening arrhythmia. Unlike the conventional defibrillation which uses high-voltage electric shocks associated with severe side effects, the new method of wave emission from heterogeneities (WEHs) merits close investigation. In our previous studies of the WEH to terminate arrhythmia in idealized conditions, we found that a circularly polarized electric field (CPEF) not only needs a lower voltage, but also has higher efficiency than a uniform electric field (UEF). But the effect of a CPEF on a real cardiac heterogeneity with irregular boundary shape remains unknown. Here, we consider elliptical heterogeneities whose boundary curvatures and orientations change in a similar way as irregular heterogeneities and study the effect of the changing boundary curvature and orientation on the WEH. We find that, unlike the UEF, the CPEF is not affected by the change of boundary curvature and orientation. Besides, the CPEF needs a lower voltage to induce wave emission from an elliptical heterogeneity than the UEF. Hence, it has advantages for the application of the WEH in clinical treatments.