Figure 1: VARP methodology.

(a) Flow chart summarizing the VARP protocol. (b) Contrast-enhanced cardiac MRI stack (left), with landmark points and splines delineating the endocardial and epicardial surfaces (middle), respectively, and the resulting ventricular segmentation (right) into non-infarcted myocardium, grey zone and scar. (c) High-resolution ventricular structure model (left) with estimated fibre orientations (middle). Although fibre orientation is assigned to each finite element in the computational mesh, a tractography approach is used here to visualize the general fibre orientation. Action potential traces from the non-infarcted myocardium (red) and grey zone (green) are in right panel. (d) VARP pacing sites on the endocardial surface of the ventricles (left panels) and a corresponding colour schematic (right) of the myocardial wall segments (numbered), as per the American Heart Association nomenclature, in which these sites are located. The train of pacing pulses is shown on the bottom right. Additional detail is provided in Methods.