A 15-year-old boy admitted with chest pain, and raised levels of Troponin I but normal viral titres, was treated acutely for presumed myocarditis. Several months later, cardiovascular magnetic resonance (Fig. 1) demonstrated a dilated and impaired left ventricle, with an ejection fraction of 42%, and normal proximal coronary arteries. Late gadolinium enhancement, indicative of myocardial damage, suggested ventricular scarring, but T2-weighted Short Ti Inversion Recovery images, which give evidence of oedema in acute myocarditis, were normal. Full thickness scarring of the lateral wall, with corresponding abnormalities of wall motion shown on cine-magnetic resonance images, was seen on four chamber (Fig. 1a), coronal left ventricular outflow tract (Fig. 1b), and short-axis (Fig. 1c) views. Scarring of the anterolateral papillary muscle was also demonstrated (solid arrows, Figs 1b,c), and was presumed to cause the mild mitral regurgitation that was evident. Patchy focuses were additionally noted in the septum (dotted arrows – Figs 1a,c,d,e), while in certain regions there was sparing of the sub-endocardium (Figs 1b,e,f). Phase-swapped images were used to confirm that the enhanced areas were not due to artefact. The patchy focuses, epicardial regions, and distribution of late gadolinium enhancement in the lateral wall, contributed to an impression gained from study of the images obtained using cardiovascular magnetic resonance of previous established myocarditis. Though some features were compatible with myocardial infarction, the pattern of late gadolinium enhancement was highly suggestive of a non-ischaemic aetiology for the cardiomyopathy, and supported the original clinical impression of an inflammatory process. Coronary angiography (Fig. 2) confirmed that the left (Fig. 2a) and right (Fig. 2b) coronary arteries were unobstructed. These images illustrated the utility of cardiovascular magnetic resonance in assessing both ventricular function, and the potential reduction in the extent of scarring over time in the setting of viral myocarditis. The patient subsequently died, and the interpretations made from the magnetic resonance images were confirmed by the findings at autopsy.

Figure 1.

Figure 2.