Figure 6.

Relation between PST1 sites and conduction speed during the fastest pacing rate with 1:1 capture. A black outline identifies the ARVI region. Black asterisks indicate the pacing site (S₁). The magenta line indicates the position of the paced wavefront as it traverses the ARVI near PST1 sites. White triangles indicate missing speed data; black triangles are PST1 sites. (A) Propagation is smooth and parallel to the ARVI. There is a speed trough co-localized with the PST1 sites. (B) Propagation across the ARVI is complex involving the collision between an epicardial wave and a wave breaking through to the epicardium from the septum. PST1s at the ARVI do not correspond to local speed depression in this case.