A 33 year old white man presented with severe, tight, central chest pain following a flu-like illness. He had no significant risk factors for premature ischaemic heart disease and there was no history of cocaine usage. A 12 lead ECG demonstrated 1 mm ST segment elevation in leads II, III, and aVF, and leads V5 and V6 (upper panel). Initial creatine kinase was 3030 IU/l and troponin T was positive. Transthoracic echocardiography was normal and the patient was referred for cardiovascular magnetic resonance (CMR) with a provisional diagnosis of myocarditis. On cine imaging, CMR showed normal biventricular function with no focal wall thinning or wall motion abnormalities. However, late gadolinium enhancement demonstrated epicardial enhancement in the basal inferior, basal inferolateral, and basal anterolateral segments (panels A and B). This pattern of enhancement did not correspond to myocardial infarction (MI) in a coronary artery territory and supported the clinical diagnosis of myocarditis. Subsequent coronary angiography was normal. Although the one year follow up ECG showed complete resolution of the ST segments, repeat contrast enhanced CMR demonstrated persistent, but reduced, epicardial enhancement in the same basal segments.

Myocarditis can be caused by a wide variety of infectious agents and can be detected with the technique of late gadolinium enhancement. This case highlights the use of this technique for establishing a definitive diagnosis between the more common clinical entity of MI and the relatively uncommon condition of myocarditis. In addition, such unusual CMR appearances in conjunction with the appropriate clinical setting could obviate the necessity for endomyocardial biopsy in these patients.