Abstract

Duchenne disease is known as a hereditary musculopathy which affects also the heart muscle. Related to the cardiomiopathy, almost all reports in literature describe a slow onset pattern for cardiac impairment and deterioration. Only exceptionally this can take an acute form. We present the case of an 11-year-old boy who was hospitalised for typical anginal retrosternal pain, nausea, vomiting and sweating, with the onset 12 hours prior to admission. The patient is known with progressive Duchenne muscular dystrophy since 2012, genetic diagnosis being confirmed in France and he was under treatment with prednisone and metoprolol.

Besides the clinical evolution, typical ECG changes were noted (inferior ST elevation, necrotic Q wave, QS wave in inferior and then lateral leads). Biological investigations performed on admission objectified: leukocytosis with increased neutrophils, slightly inflammatory syndrome (CRP 24.8 mg/L – then 42 mg/L on the 4^thday from admission). LDH, AST, ALT, troponin T – up to 30 814 pg/ml (NV<14) – CK and CKMB were found elevated, suggestive of myocardial necrosis.

Echocardiography highlighted posterolateral myocardial wall hypokinesia, being consistent with the electrocardiographic changes of ST segment elevation in the inferior leads. Because of the severe onset mimicking an acute myocardial infarction, we had to perform a coronary angiogram. This showed normal epicardial coronary arteries. Myocarditis serology was negative. Cardiac MRI showed changes of myocardial fibrosis localised in the postero-inferior wall consistent with the ECG and echocardiography and absence of myocardial inflammatory modifications.

In the light of these changes, the dose of prednisone was increased to 60 mg/day, for 5 days, then returning to levels of 30 mg/day after reduction of the troponin about 10 times. Enalapril 1 mg/kg/day, furosemide (1 mg/kg/day) and spironolactone (1 mg/kg/day) were introduced into the treatment.