Cardiac Dynamics: The New Restitution Portrait

Several different maps have been proposed to model the dynamics of cardiac tissue. These models differ in the amount of memory they possess and thus lead to different predictions of the pacing rate at which the 1:1 response becomes unstable. Recently, we have developed a new pacing protocol for cardiac tissue that allows us to test the predictions of the models. This protocol produces a "restitution portrait" that contains a wealth of information about the dynamics and stability of cardiac tissue.