https://orcid.org/0000-0002-7845-0074
A 6-year-old child presented to our Emergency Department with dilated cardiomyopathy (DCM). Echocardiography showed global hypokinesia and severe contractile dysfunction. Blood testing showed troponin elevation and anaemia with low ferritin and folates. Acute viral infections were excluded. Further tests detected high titres of anti-tissue transglutaminase antibodies (anti-tTG-Ab), positive anti-endomysial antibodies, and genetic susceptibility to coeliac disease (CD). A diagnosis of CD was made, and patient started gluten-free diet.
To clarify the aetiology of myocardial damage, endomyocardial biopsies were performed. Histological examination showed chronic active myocarditis with necrosis, replacement fibrosis, and endocardial fibroelastosis. No cardiotropic virus was detected. Double-immunofluorescence staining revealed anti-tTG-Ab deposits in the myocardium, reinforcing the suspicion of DCM associated to CD. Further analyses also revealed the presence of anti-heart antibodies. Cardiac magnetic resonance (CMR) confirmed extensive myocardial oedema and subendocardial late gadolinium enhancement (LGE).
Due to reacutizations, immunosuppressive therapy was commenced. Patient presented clinical remission with normalization of troponin and biventricular size and function on echocardiography. At 1-year follow-up, cardiopulmonary exercise test confirmed good functional capacity and prolonged electrocardiogram monitoring showed no complex arrhythmias. The child resumed sport activity.
At 2-year follow-up, CMR revealed no oedema but residual subendocardial fibrosis on LGE. Remarkably, myocardial deformation analysis by speckle-tracking echocardiography confirmed regional abnormalities in longitudinal strain corresponding to LGE enhancement.
Regional oedema, necrosis, and fibrosis induced by myocarditis may not lead to overt abnormalities in global cardiac function and are usually not detected by conventional echocardiography, unless the amount of cardiac damage is considerable. In this setting, strain imaging might be of value in allowing detection of subclinical damage.
