Acute Myopericarditis in an Adolescent Mimicking Acute Myocardial Infarction

Abstract

Acute myopericarditis is primarily a pericarditic syndrome with variable myocardial involvement, as evidenced by elevated cardiac enzymes. It is a rare entity, exclusively seen in male adolescents and accounts for less than 2% of the cases of inpatient admissions for chest pain/pericarditis in the pediatric age group. The electrocardiographic changes of pericarditis include J point/ST segment elevation, which needs to be differentiated from the benign early repolarization pattern that is common in young adolescents and the subtle anterior ST segment elevation myocardial infarction. Differentiating acute myopericarditis from acute coronary syndromes can be challenging because they share the presenting triad of acute chest pain, ST segment changes, and elevated cardiac enzymes. The accurate distinction of myopericarditis from acute myocarditis or acute coronary syndrome is important because of their differences in risk for specific complications, prognosis, and treatment implications. We present a case of acute myopericarditis in an adolescent who presented with atypical precordial chest pain, accompanied by inferolateral focal electrocardiographic changes and significant elevation of cardiac enzymes. The differential diagnosis and management of myopericarditis is reviewed with a focus on electrocardiographic changes and troponin assays.

Myocardial Infarction in Children

“…When ST elevation is determined, there should be a progression through differential diagnosis of benign early repolarisation, pericarditis, MI, bundle branch block and left ventricle aneurism [18]. While pathological ST elevation does not show variability, J point and ST elevation seen in early repolarisation in healthy adults is generally corrected with isoproteronol infusion or exercise [19].…”

“…The presence of PR segment depression is an ECG finding which is valuable in the differentiation of myopericarditis from MI in favour of myopericarditis [18]. The positive predictive value of PR depression seen in chest and extremity derivations has been determined to be 96.7% [19].…”

“…Values more than 2 ng/ml value are especially more valuable for cardiac origin [17]. Even in cases of mild damage in myocardial cells, an increase in enzyme levels may be seen [19]. In addition, the events causing an increase in troponin levels must be known (…”

“…As myocarditis is generally seen together with pericarditis, it is known as myopericarditis. Myopericarditis may show differences according to whether the effects of the clinical findings are focal or generalised [19]. Typically, diagnosis is made from the determination of chest pain, the sound of pericardial friction, ST elevation on ECG, high levels of troponin I, cardiomegaly on telecardiography and pericardial effusion on echo ( Table 6).…”

Acute tuberculous myopericarditis mimicking acute myocardial infarction: A case report and literature review

“…Therefore, the differentiation of acute myopericarditis from AMI is of great importance due to differences in the complications, treatment strategies and prognoses between the two conditions. A large number of studies have investigated the differentiation between acute myopericarditis and AMI since 2008 (6,(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18). However, to the best of our knowledge, acute myopericarditis resulting from M. tuberculosis infection and simulating AMI has not previously been reported.…”