Figure 8.

Phenomenological model of subcellular Ca in HF atrial myocytes. (A) Average nonjunctional Ca concentration in the SR $\left(c_{sr}^i\right)$ at steady state as a function of parameter q is shown. Points shown correspond to the last 20 beats after pacing to steady state. (B) The corresponding APD is given. (C) Average Ca concentration for nonjunctional sites $\left(c_i^i\right)$ for the case of high and low coupling fidelity is shown. The inset shows the corresponding voltage time course for the duration indicated by the horizontal black line. To see this figure in color, go online.