Figure 10.

Examples of abnormal electrical excitation. (A) Example of conduction block in a 2D sheet, analogous to that observed in the 1D strand for computation of the vulnerability windows. Three snapshots in time are shown to illustrate the potential of unidirectional conduction block to develop into asymmetric, re-entrant-like activity. (B) Propagation patterns in the 3D ventricular wedge, showing normal, control pacing (upper panel) and a spontaneous ectopic beat (lower panel). The propagation of DADs, preceding the ectopic beat, is clear by the purple colored regions in the lower center panel. The voltage color bar corresponds to both panels (A,B). (C) Body-surface potential activation maps (time at which potential > 0.1 mV) associated with normal and ectopic propagation, highlighting the significant difference in spatial patterns between the two conditions.