Severe Myocardial Involvement and Persistent Supraventricular Arrhythmia in a Premature Infant Due to Enterovirus Infection: Case Report and Literature Review.

Enterovirus (EV) infections in neonates can be transmitted vertically or horizontally, with symptoms ranging from mild to severe, including myocarditis, meningoencephalitis, and hepatitis. Neonates with EV-induced myocarditis may present severe cardiovascular disease with sudden onset of arrhythmia. Neonatal arrhythmias, particularly in low birth weight or critically ill infants, can impair cardiac function and worsen outcomes. EV targets cardiomyocyte receptors, inducing apoptosis pathways and triggering cardiac conduction disturbances. We present an extremely low-birth-weight preterm infant (GW 27 + 6) who developed EV-induced myocarditis, complicated with a sudden onset of supraventricular tachycardia (SVT), pericardial effusion and bi-atrial enlargement. Despite multi-agent regimen, including propranolol, flecainide, and amiodarone, the infant showed persistent junctional rhythm until seven months of age, later transitioning to atrial rhythm with stable cardiac function. A review of previously published rhythm disturbances due to EV-induced myocarditis is presented. Newborns with EV-induced arrhythmia may require a multi-modal treatment such as a multi-agent medical regimen or, in severe non-responsive cases, an electrophysiological approach. EV infections may cause long-term cardiovascular comorbidities (such as left ventricular dysfunction or mitral valve regurgitation), necessitating continuous monitoring through echocardiography and ECG. Collaboration between neonatologists and pediatric cardiologists is crucial for effective treatment and follow-up.