Geometric remodeling of the left ventricle (LV) following myocardial infarction is associated with changes in myocardial wall stress. The objective of this study was to determine the regional curvatures and wall stress based on 3D reconstructions of the LV using magnetic resonance imaging (MRI). Ten ischemic dilated cardiomyopathy (IDCM) and ten normal subjects underwent MRI scan. The former also underwent delayed gadolinium-enhancement imaging to delineate the extent of myocardial infarct. Regional curvedness (C), local radii of curvature and wall thickness were calculated. The % curvedness change (C) between end-diastole and end-systole was also calculated. In normal heart, a short-axis and long-axis 2D analysis showed a 41% ± 11% and 45% ± 12% increase of the mean of peak systolic wall stress between basal and apical sections, respectively. There was no significant difference, however, in peak systolic wall stress from basal and apical sections (ANOVA, P=0.298) using the 3D analysis. The LV shape in patients with IDCM differed from normal subjects in several ways. First, the LV had more spherical shape (sphericity index, 0.62 ± 0.08 vs. 0.52 ± 0.06, p<0.05). Second, the curvedness at ED (mean for 16 segments, 0.034 ± 0.0056 mm^-1 vs. 0.040 ± 0.0071 mm^-1 p<0.001) and ES (mean for 16 segments, 0.037 ± 0.0068 mm^-1 vs. 0.067 ± 0.020 mm^-1 p<0.001) was affected by infarction. The peak systolic wall stress was significantly increased at each segment in patients with IDCM. The 3D quantification of regional wall stress by cardiac MRI provides more precise evaluation of cardiac mechanics. Identifying regional curvedness and wall stresses helps delineate the mechanisms of LV remodeling in IDCM and may help guide therapeutic LV restoration.