How Hyperpolarization and the Recovery of Excitability Affect Propagation through a Virtual Anode in the Heart

Figure 2

The behavior as a function of the S2 stimulus strength and the S1-S2 interval. Blue indicates that the S2 action potential propagated across the entire 20 mm strand, purple indicates that the S2 action potential propagated about halfway (to the edge of the hyperpolarized region) and then died, and red indicates that the S2 stimulus failed to excite an action potential. The points A, B, C, and D correspond to the four simulations shown in more detail in Figure 3.