Fig. 1

Cardiovascular magnetic resonance (CMR) eccentricity index (EI) and septal curvature for patients without septal flattening (a, b, c) and with septal flattening (d, e, f). CMR eccentricity index was derived as the ratio of the lateral to anterior-posterior diameter of the left ventricle (LV) at end systole (a, d). CMR septal curvature was derived as the ratio of curvature of the septum (dashed line) and lateral wall (solid line) throughout the cardiac cycle (b, e); CMR images (b, e) shown here demonstrate the time-point at which minimum septal curvature occurred in the two patients. Septal curvature across the cardiac cycle for the septum (dashed line), lateral wall (grey line) and ratio of septum to lateral wall (black line, c, f)