Fig. 2

Measurement of the native T1, post-T1, and T2 values in the left ventricular (LV) myocardium. The endocardial (red line) and epicardial borders (green line) of the LV wall were delineated semi-automatically; four segments (i.e. anterior, inferior, septal, and lateral segments) were delineated automatically by applying 15% offset to avoid partial volume artifacts (white lines). A round < 5-mm² region of interest (orange circle) was drawn in the LV cavity on pre-contrast (a) and post-contrast T1 (b), and T2 (c) mapping images. The extracellular volume fraction (ECV) was calculated using the native T1, post-T1, and hematocrit values