Figure 5.

Structural remodelling (fibrosis, scar) simulated by placing an inexcitable region near the rotor core trapped the meandering rotor from Figure 3 and converted it to stable macro-reentry. In (A) the rotor initially meanders around the inexcitable region and eventually becomes trapped indefinitely. This small scar area increased the rotational frequency of the rotor to ∼8.5 Hz. Increasing scar area (B) decreased its rotational frequency to ∼5.5 Hz. Decreasing the frequency also increased the spatially excitable gap. Panel (C) demonstrates the action potential morphology for a location between the inexcitable region and the tricuspid valve annulus in (B). Orientation: lateral right atrial view; top, superior vena cava; right, lateral tricuspid.