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Figure 1 Delayed enhancement images and semi-automatic techniques using different criteria to quantify myocardial infarct (MI) extension: 1) the full-width at half-maximum (FWHM) criterion—an initial region is determined to grow to include all pixels with signal intensity (SI) >50% of a user selected point. The maximum signal intensity (MX) inside this initial region is then determined, and the final MI extent is defined as the area presenting with a signal intensity 50% above the maximum of the initial region (MI = MX * 0.5). 2) n-standard deviation (SD) criteria—the mean ± SD of remote signal intensity (RI) under the yellow circle was determined. The extent of MI was defined as areas presenting with signal intensities above the mean value from the remote (MI = RI + SD). Measurements were done using 1, 2, 3, 4, 5, and 6 SD above the mean value.