Focal myocarditis, an unusual imitator: Case report and short literature review

Introduction. Acute myocarditis is a serious inflammatory condition of the myocardium. Clinically, symptoms may differ from case to case, and as such can pose a significant diagnostic dilemma. Here we present a case of acute focal myocarditis with markedly elevated troponins, in which diagnosis was finally made using cardiac magnetic resonance (CMR). Case outline. A male patient, 26-year-old, without cardiovascular risk factors presented with severe chest pain, diaphoresis, pallor, and dyspnea. Blood pressure was 160/110 mmHg, and electrocardiogram (ECG) showed ST-segment elevation in inferior leads. In laboratory there was an extreme elevation of Troponin. Inferior-posterior-lateral STEMI was suspected, and initial treatment was given according to that suspicion. The patient was then sent to catheterization laboratory for further evaluation, which showed absence of coronary artery disease. A working diagnosis of myocardial infarction with non-obstructive coronary arteries (MINOCA) was established. To distinguish MINOCA from other causes of myocardial injury with elevated troponins, a CMR was done, and its finding was consistent with focal myocarditis of inferolateral localization. Further treatment consisted of beta blockers, angiotensin-converting-enzyme inhibitors and avoidance of strenuous activity for the next six months. The patient fully recovered and had no further complications with ECG only showing flat T-wave in D3 lead. Conclusion. Focal myocarditis is an unusual manifestation of myocardial disease and can confuse physicians, especially if it occurs along with elevated cardiac markers and ST-elevation, but in a young patient, without any known comorbidity, this diagnosis must be considered. Here, a CMR may be a useful tool.