Background : In ischemic myocardial necrosis, the fact that myocardial necrosis spreads from the subendocardium toward the subepicardium in time-dependent manner is well known. Cardiovascular contrast MRI with Gd-DTPA enables us to define the area of myocardial necrosis exactly. We hypothesized that the patterns of myocardial necrosis might be different according to injury mechanism. Method: 47 patients with evidences of elevated cardiac enzyme (troponin I & CK-MB) and chest pain were evaluated in this study. Both coronary angiogram and cardiovascular MRI were performed to all patients within 7 days since their admission date. Contrast MRI images were obtained with gadolinium DTPA with use of turboflash sequence (Sonata, Siemens). Delayed hyperenhancement was defined the zone of hyperenhance at 15 minutes after contrast dye injection. Cine image were also evaluated in all patients. Endomyocardial biopsies were performed in 3 patients who showed the zones of myocardial necrosis were not subencardium but subepicardim in contrast MRI(endocardial sparing pattern). Results : All patients showed delayed hyperenhancement patterns in contrast MRI. There were 2 groups according to whether involvement of endocardium or not in myocardial necrosis as evidenced by delayed hyperenhancement. 40 patients (group A, 85%) showed endocardial involvement. 7 patients (group B, 15%) showed delayed hyperenhancement pattern but the portion of endocardium were not involved. 39 Infarct related arteries were identified only in group A. (p=0.001) 1 patient of group A had normal coronary artery on coronary angiogram but embolic infarction was strongly suspected with some clues such as clinical history and regional wall motion abnormality and ECG change. In group B, the findings of coronary angiogram were all normal. Endomyocardial biopsy were performed in 3 patients of group B. The findings of 3 biopsy cases were 2 cases of definite myocarditis and 1 case of equivocal finding of myocardits. Conclusion: Endocardial sparing patterns of myocardial necrosis were easily detected by contrast enhanced MRI. And this finding might be a useful clue to detect the exact injury mechanism such as ischemic or nonischemic.