Statistical index <i>η</i> as a function of <i>I</i>_<i>CaL</i> for different values of <i>I</i>_<i>Kr</i>.

<p>The calculation of <i>η</i> for a threshold of -60 mV and the last second of the burst pacing simulation. Different colors represent results for different values of <i>I</i>_<i>Kr</i>. The decrease of <i>η</i> corresponded to the gradual shift of activity from Sodium to Calcium driven waves. A value <i>η</i> = 0 corresponds to the O-type excitation patterns, as is illustrated by the dotted box. The solid line separates the B patterns from the A patterns.