Background and aimTo present a 17 yo boy with Duchenne disease, admitted in the emergency unit for precordial pain, considered myocardial infarction after clinical, ECG and laboratory evaluation. He was treated for myocardial infarction and sent for coronary angiography. Negative coronarography and dynamic angio MRI confirmed myocarditis and no MINCA tipe of myocardial infarction. MethodsClinical examination, ECG, Echocardiography, coronary angiography, Holter ECG, dynamic angio MRI and laboratory tests. Results: The patient was genetic diagnosed with Duchenne disease, mother having an autosomal recessive form. The precordial pain associated with relevant ECG changes for myocardial infarction, in the context of very high values of Troponin, CPK, CPK MB, GOT, GPT, made the ICU doctors to consider and to treat this patient for myocardial infarction. He was sent for coronary angiography, where no obstruction was found. First angio MRI described area of myocardial infarction. It was considered myocardial infarction, MINCA type and treated, being sent in Paediatric Cardiology Department to be followed. The symptoms disappeared but the ECG remained unchanged. Dynamic lab tests revealed same high value for Troponin, CRP, CPK, CPK MB, GOT, GPT, HsCRP, NT pro BNP, varying from month to months, but overlimits. A new MRI was performed at 6 mo distance with positive result for myocarditis. The cardiac involvement in Duchenne patients has specific MRI findings. Myocarditis in Duchenne patients may mimic myocardial infarction. Negative coronary angiography, corroborating with positive lab tests for myocardial infarction, very similar with myocarditis lab tests, had to determine us to exclude one of the disease. The second MRI confirmed the myocarditis lesion. ConclussionsIn Duchenne patients the laboratory tests are usually high for markers compatible with myocardial infarction, myocardial iskemia and myocarditis. When precordial pain is present, coronary angiography has to confirm the myocardial infarction. In MINCA type is difficult. Angio MRI in dynamic is recommended to be performed in a cardiology centre that manage Duchenne patients, where the MRI changes can be accurate described as positive only for Duchenne, for myocardial infarction or for myocarditis. The final diagnose for our patient was myocarditis.