Click on image to view larger version.

Figure 3 Representative action potential duration measured at 50% repolarization (APD₅₀) contour map on the right ventricular epicardium (Epi) and endocardium (Endo) in control condition (A and D, respectively), in the ST-segment elevation (Brugada-ECG) without phase 2 re-entrant (P2R) extrasystoles (B and E, respectively), and in the Brugada-ECG just before P2R extrasystoles (C and F, respectively) and representative optical action potentials at each site (a to c). White arrow = initial site of P2R. DR = dispersion of repolarization; GR_max = maximum gradient of repolarization.