Myocarditis: Diagnostic value of MR imaging and CT

There is a growing consensus to recognize the role of cardiac magnetic resonance (MR) imaging in the diagnosis of myocarditis. The most characteristic finding is the presence of subepicardial enhancing areas in the inferior and lateral walls in delayed-enhanced MR sequences. Segmental wall motion abnormality may be present in the myocardial segments that can be different from those exhibiting the myocardial damage in delayed enhancement sequence. These MR features provide accurate information on the type of myocardial involvement, and probably are able to assess the severity of the disease. Moreover, these MR patterns as well as others may distinguish acute myocarditis from acute myocardial infarct, both on first-pass perfusion images and on delayed-enhancement images. Recent improvements of computerized tomography (CT) make it a challenging method for cardiac MR to assess myocarditis. By providing similar results in terms of myocardial involvement, and by adding information on coronary arteries, ECG-gated MDCT could be a useful alternative non-invasive diagnostic test in the early phase of acute myocarditis.