Effect of Model System.

<p><b>A. Electrograms shown from FitzHugh-Nagumo (FHN) Model Rotor.</b> The left panels show action potential movie snapshots of a FHN rotor. The white stars indicate the position of electrodes shown in right panels. Local action potentials, unipolar electrograms and bipolar electrograms are shown in the right panels. At the central bipoles, in panels (i) and (ii), broad deflections are seen, associated with high Shannon entropy (ShEn) seen in the ShEn map (lowest left panel). At the periphery, in panels (iii) and (iv), sharp local bipolar deflections are seen associated with low ShEn. The trajectory of the spiral wave tip is shown in the left panels in black, and on the ShEn map as a blue circle. The area of maximum ShEn overlies the pivot of the rotor. <b>B. Electrograms from the Luo-Rudy Ventricular Myocyte Model Spiral Wave.</b> A similar pattern of high ShEn associated with the pivot zone is seen. The left panels show action potential movie snapshots of a LRD rotor. At the central bipoles, position (i), (ii) multi-component EGMs are seen, associated with high ShEn (lowest left panel). At the periphery (panels (iii, iv), sharp local bipolar deflections are seen which are associated with low ShEn in the corresponding region on the map. The meandering trajectory of the spiral wave tip is shown in the left panels in black, and on the ShEn map in blue. The area of maximum ShEn overlies the pivot. Histograms are shown on the right panels. These show a broad distribution in the pivot zone bipole (panel (i)) associated with high ShEn, and a narrow distribution bipoles (iii), (iv) and lower ShEn at the periphery. <b>C. Electrograms from the Courtemanche Ramirez-Nattel-Atrial Myocyte Model Spiral Wave.</b> A similar pattern of high ShEn associated with the pivot zone is seen. The left panels show action potential movie snapshots of a CRN rotor. The white star indicates the position of electrodes. At the central bipoles, positions (i),(ii) multi-component EGMs are seen, associated with broad amplitude distribution and high ShEn. At the periphery (panels (iii, Iv), sharp local bipolar deflections are seen which are associated with narrow amplitude distribution and low ShEn. The meandering trajectory of the spiral wave tip is shown in the left panels in black, and on the ShEn map in blue. The area of maximum Shannon entropy overlies the pivot.