Gadolinium-enhanced magnetic resonance imaging in acute myocardial infarction

To investigate the clinical application of gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA)-enhanced magnetic resonance imaging (MRI) in the management of acute myocardial infarction (AMI), we examined 44 patients with AMI within 1 month after onset. Enhanced images were classified into 4 types: nontransmural (type 1), transmural and homogeneous (type 2), transmural and marginal (type 3), and no enhancement (type 4). Each enhancement pattern was correlated with angiographic and thallium-201 imaging results. The redistribution images of thallium were graded on a 4-point scale from 0 (normal) to 3 (markedly reduced or absent activity). The percentage of the perimeter affected by asynergy was obtained from the left ventriculogram. Peak creatine kinase and the percentage of asynergic perimeter were significantly higher in type 3 than in other type patients. End-diastolic volume index was significantly higher in type 3 than in type 2 patients. Left ventricular ejection fraction was lowest, and end-systolic volume index, thallium-201 score, and incidence of wall thinning on MRI were highest in type 3 patients. Therefore, the transmural and marginal enhancement pattern (type 3) was compatible with extensive myocardial infarction with infarct expansion and less viable myocardium. In the other types, the infarction was small to moderate in size and left ventricular function was well preserved. Thus, Gd-DTPA-enhanced MRI may be useful in the evaluation of left ventricular function and myocardial viability of the infarct region after AMI.