Clinical, paraclinical and prognostic aspects of acute myocarditis

Introduction Acute myocarditis is one of the most challenging diagnoses in cardiology. It is based on both clinical and paraclinical parameters. Myocarditis often presents as an acute coronary syndrome. Methods This is a retrospective study conducted between 2001 and 2017 in the cardiology department at the FSI hospital in La Marsa. Epidemiological, clinical, paraclinical and prognostic parameters were analyzed. Results Twenty six patients were registered including 3 women and 23 men. The average age was 37 (23–68 years). Symptoms were preceded by Influenza-like symptoms in 15 patients. Only 3 patients had fever. The most common symptoms were: angina in 11 patients, atypical chest pain in 9 patients, isolated palpitations in one patient, acute heart failure in 2 patients, and cardiogenic shock in 3 patients. The electrocardiogram (ECG) showed repolarization abnormalities in 17 cases, ventricular arrhythmias in 2 cases, sequelae of necrosis in 3 cases, atrial fibrillation in 2 cases and a normal ECG in 2 cases. The troponin assay was positive in 18 cases. Fourteen patients had a biological inflammatory syndrome. The etiological investigation concluded to a viral cause in 24 patients including a case of Rickettsiosis and a case of CMV infection. Myocarditis was a complication of chemotherapy in 2 cases. Transthoracic echocardiography demonstrated a decreased ejection fraction in 5 patients and segmental kinetic disorders in 12 patients. Associated pericarditis was noted in 2 patients. Twenty patients underwent myocardial MRI confirming the diagnosis of myocarditis. 24 patients have progressed to a restitution ad integrum. Only two patients kept a decreased left-ventricular function with segmental kinetic disorders. Conclusion Acute myocarditis may have different clinical features. It represents a major diagnostic issue, insofar as it simulates a myocardial infarction. In this context, cardiac MRI is of major interest for the differential diagnosis.