Significance of late gadolinium enhancement in cardiovascular magnetic resonance imaging (CMR).

Cardiovascular magnetic resonance imaging (CMR) permits optimal differentiation between normal and diseased myocardium with the use of gadoliniumbased contrast agents and special magnetic resonance pulse sequences. Imaging is performed 10-20 min after contrast agent application to produce so-called late gadolinium enhancement (LGE) images which depict diseased myocardium with excellent reproducibility. Areas showing LGE correspond to zones of myocyte necrosis or myocardial fibrosis as shown by comparison with histopathology. Typical patterns of hyperenhancement exist in ischemic heart disease but also in dilated cardiomyopathy, hypertrophic cardiomyopathy and other inflammatory or infiltrative myocardial disease and are described in this article. LGE-CMR is helpful to distinguish advanced ischemic heart disease from nonischemic dilated cardiomyopathy. In ischemic heart disease LGE can also predict the functional recovery after revascularization procedures by directly showing the remaining viable myocardium. LGE may also become useful to predict malignant arrhythmias in patients with ischemic heart disease or nonischemic cardiomyopathy. This may lead in future to an increased role of LGE-CMR as a prognostic tool.